Planet Nottinghack

22 May 2019

Martin Raynsford hackergotchi for Martin Raynsford

Hospital Runes 383

The Empire game year is 383 this year so I had a bit of a chance to play around with the hospital runes I normally cut for them. The base rune has two diamond shapes which look a bit like the gaps between 383. 

by (MSRaynsford) at 22 May 2019 09:52 PM

15 May 2019

Martin Raynsford hackergotchi for Martin Raynsford

Large Countdown Clock

The From Shadows team requested a large countdown timer to count 2 hours, I offered a full 99 minutes instead to save myself an extra digit but I think this giant RGB seven segment display fulfils the brief well. I opted not to use a real time clock chip because it only drifted a few seconds over the two hour period which is close enough. The illumination is provided with WS2812 LED strips and the controller is the ESP8266 so if I desperately wanted accurate timing I could always implement an NTP server and connect to the local wifi. Again, I wish I'd taken more photos of this project in action but I may well get another chance if I build another one for our local ninja warrior training gym

by (MSRaynsford) at 15 May 2019 11:30 PM

13 May 2019

Martin Raynsford hackergotchi for Martin Raynsford

Cyber Control Panel

Coming in very highly on my overdue project list is this Futuristic control panel for the From Shadows event that happened over a month ago. I was rushed and wish I had photos and a video of more of the details. I don't even appear to have photos of the separate parts.

The brief was for a control panel that could be split up into parts that were acquired throughout the course of the weekend. I wanted to take it a step further and split it up into parts that make the panel functional when connected back together. Two large hex bolts on the back could be removed, without tools, to provide access to two compartments. The first compartment was designed to house a 'battery', the second compartment had some exposed connectors. When the battery was inserted into the first compartment and the the connectors bridge with the appropriate loop power was supplied to the front of the device.

The switches in the bottom left hand corner have illuminated LED's, flip both of these switches on to power up the rest of the font panel. The top left hand corner splits off in an attempt to look like battle damage. The isolinear chips in the bottom right hand corner all become illuminated when they are inserted into their slots. They use florescent perspex and UV LED's to provide a sensible glow. The final touch is the wooden controller in the middle of the panel. One magnet at the top of the slider allows the slider to lock into positions on the board where other magnets are located. (Apparently it jumped out of the users hand the first time providing many oohs and aahs). A second magnet in the bottom of the slider activated a magnetic switch and turned on another UV LED in that location, so as you move the slider around the panel illuminates underneath it.

I think it went down well at the event and I'm already lined up to make props at the next event so that must be a good thing :)

by (MSRaynsford) at 13 May 2019 09:21 PM

23 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

From Shadows Teleport Return Device

The next prop for 'From Shadows' was this teleport return device. Units teleport into hostile territory and this is the gadget to teleport them all back again. This one has some added electronics to make it more interesting. A big red button activates the device once the small switch has turned it on. The whole thing counts down from 10 before flashing some lights to signify it's active. A nice big handle on the top makes it easy to carry. Although it's large it's pretty lightweight because it's poplar ply. The whole thing was painted with metallics and sprayed with varnish to make it water resistant. 

by (MSRaynsford) at 23 April 2019 05:25 PM

20 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

From Shadows Rad Field Generators

From Shadows Larp recently ran it's third event and I had the fun of making quite a few different props for them this time around. First up was this set of rad-field generators. Most of the shaped pieces are laser cut, the vertical poles are broom handles cut in half and the fluorescent orange core are stacked gears that were cut out of the cake rings. Texture was added to the base plate but refocusing the laser to make 5mm wide beam, this was quick and easy and showed through the paint finish.

The whole unit was primed with grey paint and then sprayed loosely with army green cans, the lack of complete coverage actually gave it texture and interest. The poles were sprayed with metallic silver paint and the gears with the most fluorescent paint I could find. The upper part of the unit was only inserted loosely into the base so they could be dismantled for storage and removals. One lucky feature is that the two sides slotted together to take up half the space in storage.

by (MSRaynsford) at 20 April 2019 06:57 PM

17 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

Kickstarter fulfilment

With another successful kickstarter firmly in the bag I'm not stuck in the fulfilment doldrums. I've just about nailed a quarter of the puzzles in the last week and now that KS has paid out I'm good to do the shipping. It always surprised me last time just how long it actually takes to bundle orders into envelopes and label them all correctly. Whole days were spent making sure the right things went into the right bags. Hopefully I'll be a little more efficient this time round and then it's just onto more and more puzzles. The most common tier was for all eight puzzles so in theory I have half as many customers this time round anyway which should make things a bit quicker.

I've been having some interesting ideas and experiments with the machine too while doing all this cutting so I should be able to squeeze in some more sensible posts as soon as I get this stack moving on to their owners.

by (MSRaynsford) at 17 April 2019 02:44 PM

15 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

Mystery Gaming Tokens

A lot of the time I just make what I'm asked to make without delving into the details. These gaming tokens follow along those lines (Although I have been promised the rules at some point). They're cut from 9mm poplar ply to make them nice and chunky and I even managed to find 18 different colours to try for these sample sets. Each game requires 4 sets of 12 so I ended up making 4.5 sets for sample.

by (MSRaynsford) at 15 April 2019 10:01 PM

13 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

Bingo Balls

I recently had cause to engrave a bunch of wooden bingo balls for a project. I bought some cheap 40mm balls from the internets and stained them with some indian rosewood strain. The numbers themselves were engraved and outlined on both sides of the balls to make them easy to read from multiple angles. The balls were held loosely in place under the laser head, lightburn really helped with this project because it allowed me to set the reference point as the centre of the image. I could align the red dot to the very middle of the ball and know that the number would be centrally aligned.

by (MSRaynsford) at 13 April 2019 09:45 PM

11 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

Foam Scales

A bit of a sad one for these scales. They were for a cosplay costume based on Avengers Endgame. It turns out that 2mm foam was too thick for the scales and the 1mm foam didn't arrive in time for the convention. These scales were cut on my newer laser though and the RF tube seems to have made a lot of difference to the vertical cuts. The 100W glass tube blasts away a big 'V' shape in the foam where as the 30W seems to have cut away just enough with minimal reflections. I shall cut more foam on the faster machine in the future.

by (MSRaynsford) at 11 April 2019 09:33 PM

09 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

Custom Coffee Stencils

I was asked to make some custom coffee stencils but I wasn't really sure which material would be best so I tried a range of different types and thicknesses. I think the Petg worked the best of the three materials I tried, it cut quite nicely once it had been masked front and back with vinyl transfer tape.

by (MSRaynsford) at 09 April 2019 09:16 PM

08 April 2019

Martin Raynsford hackergotchi for Martin Raynsford

Cake Rings

So while my kickstarter was ticking over I had a fair amount of time to complete some other large projects. This one involved me making 35 sets of rotating cake rings, where a set includes one big ring and one small ring. These rings are going into Harry Potter cakes as per the video in the link.

The trouble with ordering parts from China like this is that half of them were different. Many of the larger rings came with 3 mounting holes instead of 4 and none of the holes were drilled all the way through so I was unable to bolt them in place. I ended up drilling through the rings myself which was dull and time consuming.

by (MSRaynsford) at 08 April 2019 10:33 PM

26 March 2019

Martin Raynsford hackergotchi for Martin Raynsford

Final 48 hours for Kickstarter

My Kickstarter campaign just entered the final 48 hours, it's currently just under £12,000 raised or 1200% funded which actually makes it more successful than the first time around (especially if you count all the increased sales of the existing 4 designs). There is still time to hop on the bandwagon though and get yourself some of the new puzzles hot off the press. Or please share the link one more time if you know someone that would like them. It's going to be a busy month next month but at least I should have some time in between puzzle runs to blog all the things I've been making this month.

by (MSRaynsford) at 26 March 2019 09:08 PM

21 March 2019

Martin Raynsford hackergotchi for Martin Raynsford

Wargaming Tokens

While I'm stuck in production hell, filling most of the week with a quantity of cake based parts, I just managed to cut a stack of tokens for a wargaming friend. I bundled them up in a bag ready for the post, vac sealing the bag makes them easier to pack.

by (MSRaynsford) at 21 March 2019 11:06 PM

17 March 2019

Martin Raynsford hackergotchi for Martin Raynsford

1000% funded on my Kickstarter

My kickstarter campaign continues to tick over in the background, amazingly I just reached 1000% funded. I shall have to make another 6-700 puzzles next month in a similar scale to the previous campaign. All of this work and secret escape room projects and large cake projects are keeping me all rather busy at the moment. There are lots of things I mean to write about but am just not finding the time, hopefully I can squeeze some of those things in too.

by (MSRaynsford) at 17 March 2019 11:32 PM

12 March 2019

Martin Raynsford hackergotchi for Martin Raynsford

Ninja Warrior Button

Ninja Warrior Button tied to wifi controller
Over the last few weeks I've been playing around at Ape Index Leicester, it's like a ninja warrior training gym with a climbing wall. I'm mostly playing but I've certainly been getting fitter because of it, I was talking to the owner who discussed a big red button project like they have at the end of the ninja warrior course. Wiring one up is tricky because the place is so big so it sounded like a perfect match for some of my ESP8266 work.

It's a simple browser based stopwatch app written with javascript, this is served up from the ESP8266 as an access point. A websocket is opened to transfer data too and from the browser without refreshing the page. When you press start on the screen the light on the button becomes illuminated, when you push the big red button the timer stops counting, so you can start the system from one end of the course and see what time they get at the other end.

This is very much a fun project I threw together in an hour this evening while cutting useless machines. The internals definitely reflect this, thrown together with sticky tape and bits. I used a rechargeable battery for a power supply but some strain relief on the cables would be preferred. Ultimately this system should tie into a larger screen to show the current time but that's future work.

Big Red Button Simple Box
On/Off switch on the back of the box

Very messy impromptu internals including rechargeable battery

by (MSRaynsford) at 12 March 2019 10:19 PM

04 March 2019

Martin Raynsford hackergotchi for Martin Raynsford

Oversized Chess Set

I did say that this Oversized Chess Piece was the start of something bigger and here it is. There are a few tweaks and changes such as the arrow points on the base to show the forward direction and these are about 20% bigger again.

What good is an incomplete chess set I hear you ask? This one has been made specifically for one of the puzzles at Escape Asylum. We recently went to visit and completed Riiitual, escaping with time to spare. We've done a few different escape rooms and I think I liked this one the best, it was definitely challenging, the puzzles fit the theme of the room well. 

The only thing that let it down slightly was a plastic chess set with some manhandled broken pieces. Being a local nerd with a laser cutter I thought it only fitting to offer some decent wooden replacements that can take the punishment. Once I got started there were quite a few things that could be upgraded so I've now made a few new props for them which I will never be allowed to show you.

If you want to see exactly what I've been making you'll have to book yourselves in to Riiitual, just don't forget to take a few of your smartest friends with you. I'm keen to try their other rooms before I'm called upon to make props for them :P

by (MSRaynsford) at 04 March 2019 10:09 PM

28 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Fractal Puzzle Kickstarter Success

The first time I ran a kickstarter I just kind of launched it and told a few people once I'd done it, the whole thing funded in 24 hours which was great news. This time around I was a bit more prepared, I contacted people in advance, sent out some samples for review and generally made people aware that it was going to happen. This time I was 100% funded in 1 hour 58 minutes.
I realise I was only asking for a paltry £1000 each time and it doesn't really bear any relevance to the amount required to complete the task but it's still nice to see that people were keen to be involved this time. We hit nearly £4K in 24 hours which is a promising start, now I need to push it a bit to keep up some of that momentum. In general though it looks like it's going to be another successful campaign and I'm going to have another busy month.

by (MSRaynsford) at 28 February 2019 08:52 AM

26 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Fractal Puzzle Kickstarter has been launched

I just launched my new kickstarter campaign for the second set of fractal puzzles, now is a good time to jump on board and grab yourself an early bird bargain.

by (MSRaynsford) at 26 February 2019 08:10 PM

25 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Kickstarter at the ready

With my Kickstarter campaign ready and waiting for approval from Kickstarter I can positively say that my new puzzles are going to launch any day now. With the puzzles so close I can also announce that there will be another set of four puzzles based on the Peano curve and variations of it known as the Wunderlich Curves. 

Curves 2 and 3 are very standard puzzles compared to the original set of four, I simply found the repeating sections and subdivided the puzzle accordingly, it makes them just as tough as the originals to solve. The Peano curve and Wunderlich Curve 1 were quite a bit harder to create and I had to wait for inspiration to strike. The repeating section on those puzzles is obvious but it was hard to find 13 different ways to split the puzzle without making it too simple. I'm sure you'll appreciate the solutions I found and enjoy their fiendish new complexities.

My extended family were subjected to timed testing a few weeks back and nearly all of them gave up within the hours allocated, just one uncle and aunt persisted until they had solved their first puzzle in 2 hours. I have high hopes that this new range will meet the expectations laid out by the first set.
Now would be a very good time to follow me on Kickstarter if you would like to snap up some of the early bird puzzles sets 

by (MSRaynsford) at 25 February 2019 08:22 PM

20 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Light bit of repair

Note how most of the LED's have stopped working
There was a single row of leds mounted under the gantry on my laser cutter, over the years the LED's have slowly stopped working and they were in a bit of a sorry state. I'm going to be installing a new camera into my laser cutter at some point and lighting is always important so it was a good time for an upgrade. Instead of one strip of light that moves and creates ever changing lighting I thought it would be better to put two static strips one the Y rails.
Removing the 24V wire from the loom up to the gantry
The old strip lights are pretty disgusting from years of cutting
I pulled the LED strip off the bottom of the gantry, it was pretty badly stained from years of laser cutting. The new lights are weatherproof, silicone coated so they should stay cleaner and functional for a lot longer. They are wired into the existing switch so they can be turned on and off from the outside of the machine.

The new lights are wired into the existing switch
A quick test of the new lights to confirm they take less than 1A
The existing power supply is only rated for 1A at 24V so it was worth taking a few seconds testing the lights to make sure they didn't draw too much current. In hindsight I would have made the strips slightly shorter (less bright and less current).

Drilling a new hole to run the wiring through
The left wiring is fed into the loom alongside the flow sensor
I had to drill a new hole to route the wires on the left hand side of the machine. I used a step drill bit to ensure there were no sharp edges to the hole when I was pulling the wire through. The wires were then routed down the back of the laser and alongside the water sensor wires

Silicone covered lights held down at the ends with gaffa tape
The right hand light feeds through the limit switch hole
The strips have a self adhesive backing but where the ends were terminated with heat shrink they weren't sticking to the rails. Liberal use of super sticky gaffa tape holds the ends down. The new lights are super shiny and provide a nice even light across the entire surface (or at least to the human eye they do, no doubt they'll give massive bright patches on the new camera but that's a future problem).
The new lights in all their shiny glory

by (MSRaynsford) at 20 February 2019 09:25 PM

12 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Oversized Chess Piece

I made this bishop as a sample piece, hopefully this is the start of something bigger and I don't just mean an oversized chess set. It's made from 6mm birch so it's nice and sturdy and it was finished with a lasercut disk of felt on the bottom. I can't decide if I should do the other pieces with black paint or brown wood stain but I'll probably try both.

by (MSRaynsford) at 12 February 2019 10:51 AM

10 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

2nd Fractal Puzzles Kickstarter

Last summer I ran a moderately successful kickstarter campaign, where I did a production run of the fractal puzzles I designed several years ago. Since then I've had numerous requests to design more fractal puzzles and after a fair bit of research I have discovered four more space filling curves that lend themselves to fractal puzzles. I'm going to be kickstarting these in the next few weeks so now is your chance to follow me on KS and snap up one of the early bird deals as soon as they get launched. I will obviously post to the blog here when the campaign goes live too. In the meantime, stay tuned.

by (MSRaynsford) at 10 February 2019 02:14 PM

07 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Tweaks and Changes

The laser upgrade went remarkably smoothly and the laser cutter was functional but there were a few minor changes and improvements that needed to be done.

Fixing the screen image
Image flipped on the controller
The first and most noticeable tweak for my new Ruida system was to fix the screen display. Most of my cuts are symmetrical so it was a day or two before I noticed that the image on the screen was mirrored. The laser cutter was cutting the correct way so I knew this had to be a simple setting on the controller. In the menu system is an option called 'Screen Origin' we have to set this to 'Top Right' so that the controller knows it's cutting from the same corner as the laser.

Screen origin setting
Screen Origin should be set to top right
Image corrected on the controller
Wiring in the water protection
The additional wire patched into the WP line on the PSU
The lid switch and the water flow detection were already wired directly to the high voltage power supply, this ensured that the laser wasn't going to fire accidentally during any of the previous testing. The Ruida controller is actually capable of understanding these inputs and generating a warning when something is wrong. Patching this input into the controller is as simple as running a wire from the WP connection on the laser PSU into the WP1 input on CN4 of the ruida controller. When this is wired correctly LED #9 will flash on/off when the inputs are activated.

The Ruida controller is actually capable of understanding the difference between the lid switch input and the water flow input. It would be possible to split the two inputs before they go into the laser psu but this is a suitable compromise for the moment.

The WP line connected to pin4 CN5, led #9 is lit
Setting up the water protection from RDWorks
The controller needs to be configured to use the water protection inputs, this has to be done from within the RDworks software. File->Vendor settings (password RD8888) allows you to see the settings on the machine and you can read/write the water protection settings.

The error that occurs when you start a cut
Once configured this is the error message you get when you start a cut without the safety switches engaged.

Autofocusing hack
Z limit switch hiding in the darkness
Lightburn has some interesting features where it's able to automatically adjust the height of the bed if you tell it the material thickness. The controller needs to know where the zero point for the Z axis is before it can do that, some lasers have an autofocus probe mounted to the head to sense the thickness of the material. My laser cutter only has a limit switch mounted on the Z axis, when that white collar moves to the top of the rod then it triggers the switch. The trouble is that it doesn't take into account for the honeycomb or the knifebed sat onto of the bed. The switch doesn't trigger until after the metalwork crunches itself into the nozzle.

A well positioned saw blade triggers the Z switch
The solution was to make the bed trigger the sensor a lot lower down. I was thinking about mounting a bracket onto the side of the bed but it's all at a very tricky angle and I would probably have to dismantle the Z axis to get to it. As I looked at it I realised I could slide a thin strip of metal between the bed and it's own brackets that would stick out under the switch. I ended up using a saw blade wedged into the gap to trigger the Z switch at a suitable height. (Don't forget that the telescopic tube of the Z axis gives you a wide range of suitable heights)

Setting the Z focus manually for the last time
The Z axis is now capable of zeroing and limiting before it crashes into the nozzle, that doesn't mean it's actually in focus though. The focus is a few mm below the zero point but there is an easy way to calculate what the offset is. If you adjust the focus manually you can read the offset from RDWorks and you can use that value in the controller. Now when you use the autofocus button the laser bed will move all the way up to the zero position and then back down until the surface of the bed is on the focal point. I may adjust this to be 2.7mm lower because I most commonly use poplar plywood.

Current position and new focus depth

While you're under the beds give it a good cleaning
While you're playing around under the laser cutter you might as well give it all a good clean, this was the state of my metal bed after about 6 months of cutting. I used a bbq cleaning tool with a nice metal flat edge which was great for scraping all the build up residue that had clung to the bed.

by (MSRaynsford) at 07 February 2019 02:54 PM

Leetro Spare Parts

Leetro MPC6515 Control System
Since I recently upgrade to a ruida controller I figured I should sell the spare parts that I no longer need, a second security dongle is always handy or a brand new control panel should your buttons be wearing out. 
Finally I'm listing a complete Leetro system, sure the ruida controller is better than the leetro system but if you've got a limited budget then you can snag a bargain and any kind of DSP controller would be an improvement for a K40.

Lasercut 5.x Security Dongle

PAD-03E control panel

by (MSRaynsford) at 07 February 2019 01:13 PM

06 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

LARP Vant Shields

6mm ABS inner core of shields
This project turned out to be quite the collaboration between makers. I was asked by Eldritch to cut some thick ABS plastic that was going to go inside a pair of ballistic shields. There is a growing crossover between LARP and Airsoft and new rules being developed to cope with both. These shields don't have to follow the normal, foam rules, and actually need to be stiffer and stronger to withstand all the incoming ball bearings. The possibilities of windows in shields now becomes an option so I cut some 6mm perspex for windows and wooden surrounds to hold them all into place on the shield.

The shields then went on to Eldritch who covered them in a layer of foam, bolted all the parts together and generally turned them into functional shields.
Shields at the Eldritch workshop
These shields look great however nice shiny shields don't really fit into the post apocalyptic style game they were destined for, that's when the owners took over and did a pretty epic job of weathering the shields ready for the event. Junkyard Grizzly took one shield and Dust Monkey took the other adding their own personal style. These things look amazing and fit right in to the Metro style game they were destined for.
Junkyard Grizzly Weathered Shield
Dust Monkey Weathered Shield

by (MSRaynsford) at 06 February 2019 09:55 PM

05 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Saxon Shield

To go with the saxon helmet we made a super simple shield. It's literally just a circle of 3mm birch with a handle cut through the middle. I had a vacuum formed shield boss left over from the roman shield we made previously. The details were just drawn on with low power lines which made it easy for Eli to paint. He even got to wear my chain mail shirt to finish the look off.

by (MSRaynsford) at 05 February 2019 04:12 PM

03 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Saxon Helmet

Simple helmet design covered in scales
Homework last week was to build a helmet for the school battle reenactment. We joined a few strips front to back, left to right and around the circumference, filled in the quarters and then covered it all in cardboard scales. We cut a whole sheet of scales on the laser and painted them metallic silver, leaving them all connected at the top made them easy to apply to the helmet.

Sheet of laser cut scales

Handy head model

by (MSRaynsford) at 03 February 2019 09:30 PM

02 February 2019

Martin Raynsford hackergotchi for Martin Raynsford

Light Fittings

The new light fittings

The light in our lounge is pretty dim, really we should replace all the lights with better ones but we're waiting to redecorate everything at the same time. The idea suddenly hit upon me that I should replace the shades with something better (and laser cut). The old fittings basically block out a large chunk of the light being produced so I copied the size and shape but reproduced them in semi transparent materials. The new light fittings, three of them, allow much more light to actually enter the room making it appear much brighter.
The old light fittings blocking most of the light

The fittings were made from 6mm clear acrylic which was double stacked for strength. Double sided carpet tape was placed around the edge to affix the polypropylene to the front. Simple but effective.

Curved former for the polypropylene

Light fitting ready to be placed on the light

by (MSRaynsford) at 02 February 2019 05:06 PM

31 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

This one simple hack could save you money

Coolflow DTX from Hydratech, good for lasers
We're having a bit of a cold spell in the UK (I'm aware the US has it worse too) but we're not used to cold weather, temperatures dip below zero and we all panic a bit. One of the things that people always forget is that the glass tube in the back of their laser cutter is water cooled. If the water freezes it will expand inside the tube and cause the glass to smash, that's going to leave a hefty bill to replace the tube. Putting some antifreeze in with the coolant is easy to do and it's going to save you the worry. If your laser is in the garage and isn't warm and snuggly inside your house it's well worth doing.

If you have the CW3000 you're going to need 2.25L of antifreeze and if you have the CW5200 you're only going to need 1.5L. The internal reservoir of the CW5000 series is smaller because it actively chills the coolant. Small quantities can be purchased via ebay and the usual sources at sensible prices (or from laser importers at inflated prices), 5L bottles can be bought directly from Hydratech.

On the back of the chiller is a drain outlet (the bottom left corner), simply unscrew this cap and drain the approximate amount of liquid into a measuring jug. Dispose of the water in the usual way. Then simply pour the antifreeze back into the top of the chiller. Once the chiller is turned back on you should see the coolant start to circulate through the laser tube.

Thanks to Graham from DeathZap Studio for prompting this post after our conversation on the subject

by (MSRaynsford) at 31 January 2019 01:35 PM

26 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

New Laser bench

New laser bench with sheets stored underneath it
I've had my new laser cutter resting on it's packing create for several months, I recently ordered 100 sheets of Birch plywood, 800x600mm and I still had about 50 sheets of poplar left from the last order so all of that needed a new home inside the garage (rather than the utility room). I rummaged through the scraps and planks in the shed and I already had enough parts to make a new small bench so I took my trusty little helper and we made a bench one day (you can tell the girls were out because we made it in the kitchen to avoid the rain).
The bench works well, it's a little bit wobbly but it does bring the laser up to a nicer height for working at. As you can see I still have to plumb the extraction in to the existing outlet rather than opening the garage, especially in the cold weather, everything takes time.

My helper for the day
Child shown for scale
Laser in place on new bench

by (MSRaynsford) at 26 January 2019 10:13 PM

25 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Door Strip revamp

Door strip between the raised wooden floor and the kitchen tiles.
I made this door strip 18 months ago very much as a test piece. Even then it was showing signs of wear so the fact it lasted all this time was great. The wood had warped a little and it had lifted on one side. The front edge was a little cracked from being stood on (it was too long) and the whole thing was pretty grubby from general use. I reinforced the underside of the strips with some 1.5mm birch (it was only made from 0.8mm originally), I also reinforced the stack of pieces too. The whole thing was sanded, reglued and varnished and it's like new again but this time done as a proper job. Lets see how long it lasts this time around.

Grubby door strip, halfway through sanding
It's so long clamping it flat to the dining room table was the best option.

by (MSRaynsford) at 25 January 2019 10:35 PM

23 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Christening Cake Toppers

Here is a picture of the cake toppers actually in the cake too. It's another cake made by Dinkydoodle designs and the toppers are cut from 3mm mirrored acrylic.

by (MSRaynsford) at 23 January 2019 08:32 PM

22 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Simple Boxes

I was asked to put together a handful of simple box shapes which are going to be decorated and turned into war gaming terrain. I worked from a simple diagram and made as many boxes as possible from 4 sheets of 2mm mdf (600x900). The trick is making the finger joints mesh together to cut as efficiently as possible.

by (MSRaynsford) at 22 January 2019 10:35 PM

21 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Testing the Ruida Controller

So far in this series of blog posts I've talked about setting up the ruida controller and wiring it into the laser cutter, now is the point where it needs to be tested to ensure that it actually works as intended. In the previous post I failed to mention that the power connector needs to be rewired but it's a straight forward swap of GND and +24V. Once the controller can actually be turned on we're ready to start testing.

Testing Automatic Features

Safety is all important while testing the machine, there are moving parts and laser beams during this whole process so care should be taken. The big red emergency stop on the machine is always close to hand, the key switch similar. The safety interlock lid switch for the laser is still wired directly to the high voltage power supply so the laser will not fire with the lid open or the water pump off.

The first test is to ensure that both axis move in the correct direction. The controller was set up to initialise the X and Y axis to the back right hand corner when the machine is turned on. When the machine is first turned on make sure the X axis is moving to the right and the Y axis is moving to the back, if not then instantly turn the machine off. These settings can be adjusted using the 'Direction Polarity' for each axis if need be.

The second test is to ensure that the axis stop when they reach the limit switches. Manually pull the laser head to the bottom right hand corner before turning on the machine, this ensures that the X axis will hit the limit switch before the right axis. When you turn the laser cutter on the head should move to the origin and stop, if the limit switches don't register then the stepper motor will make a horrible grinding noise, simply turn the machine off and investigate.

Testing Keypad Control

Once the limit switches are working, the machine should datum upon start up. Then you will be able to drive the laser head around using the arrow keys on the keypad. Ensure that the head moves in the right direction according to the arrows.

The Z axis doesn't automatically datum, the Just Add Sharks machines only had a limit switch to detect the highest Z point, not an autofocus probe. Press the Z/U button in the middle of the arrow keys to switch the Z mode. Pushing the left arrow should make the bed move upwards and the right arrow should make the Z axis move downwards.

That basic testing proves that the Axis are wired correctly and are moving in the appropriate directions. There is one last keypad test that we can do to prove that the laser is going to fire. Put a piece of test material under the laser head and close the lid to engage the safety interlock. When you push the 'Pulse' button on the keypad the laser should fire for as long as you hold the button down.

Switching to Lightburn Control

Lightburn has a 'move' tab on the top right hand side that allows you to control the laser cutter from within the program. This panel allows you to specify precise movements of the cutting head which makes testing incredibly simply. 

Place a ruler horizontally under the X axis of the laser cutter, align the red dot with 0mm. Set lightburn up to move the head a distance of 20mm, move the cutting head led and check that the dot is now on the 20mm mark of the ruler, simples. You can repeat this for the Y axis and the Z axis by placing the ruler vertically against a fix point on the laser and moving the bed up along side it.

With this testing complete we're able to move on to some proper cutting and files. The laser cutter is now ready to run under Lightburn using the new Ruida controller. The next part to this series will detail some of the tweaks and changes required to get back to a fully functional machine, hopefully that won't take quite as long to write up.

by (MSRaynsford) at 21 January 2019 01:09 PM

07 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Rubber Stamps

A friend wanted some stamps to ink a pattern onto some material she's working with. We weren't sure if wood or rubber would be better for it so I cut a set of both. The backs were finished will little handles to make them easier to stamp, I left it all unglued so it would be easier to post.

by (MSRaynsford) at 07 January 2019 11:15 PM

04 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Wiring the Ruida Controller

The RDC6442G controller from Ruida
This is going to be quite an image heavy post describing the rewiring needed to convert between the Leetro controller and the Ruida controller. It is also pretty straight forward on the old Just Add Sharks laser cutters because all of the wires are clearly labelled. The controller was prepared in the previous step in order to make this conversion process as smooth as possible.

The Leetro (Pad03) panel on the left and the Ruida panel on the right
The view from inside the laser looking up at the control panel
The control panel is an easy place to start, both panels have just a single cable that runs down to the controller, both panels are a very similar size, with the Ruida panel being slightly smaller underneath so it will fit in the hole left behind easily. The Pad03 panel clips into place so you'll need to reach up inside the machine to work the clips loose. The cable runs down the inside of the laser and is cable tied onto mounting points inside the metal work.
The bundle of wiring loom cable tied into place

There tends to be a lot of excess wiring on these machines, a 2m long wire will service 10 different models of laser so the long wires tend to get doubled back on themselves and cable tied into a bundle. Before cutting your cables loose consider wrapping them loosely with a new cable tie. This will keep the bundle in some semblance of order and once the new cable has been passed through the bundle it will be very easy to tighten all the ties quickly.

The Ruida panel in it's new home on top of the laser
The Leetro controller in place next to the stepper drivers
In my machine, the Leetro controller is mounted vertically in the side of the cabinet, I'm able to use the same mounting holes to hold the Ruida controller in place. They're a little wide but the Ruida can rest on the bottom screws and the top screws stop it from falling forward.

The laser connection on the Leetro controller
The laser connection on the Ruida controller
The first connector I rewired was the laser control connector. It's a simple 3 wires and all are clearly labelled. 
  • GND from the Leetro becomes GND on the Ruida, this is the base voltage level for the electronics.
  • LAS becomes L-On1 on the Ruida, this turns the actual laser beam on/off
  • DA becomes LPWM1, this is the amount of power to use for the laser beam as a PWM signal.
  • WP1 is the water protection input, I have temporarily left this unconnected
  • L-AN1 is the analogue output to control the power of the laser beam, see below
There are two options for setting the power of the laser beam. PWM which is a modulated square wave and potentially more precise and an analogue signal where the voltage varies between 0 and 5V. I have chosen the PWM pin from the Ruida, a while back I upgraded my High Voltage Power supply to something that works better with a PWM input. The standard power supply on these machines should be able to accept either input. 

The Ruida controller has the option to drive two different laser beams, CN6 is an identical connector that would connect to a second high voltage power supply.

X & Y stepper motor connectors on the Leetro
X,Y & Z connectors on the Ruida Controller
The next set of connectors that's easy to convert are the X,Y and Z stepper motor connectors. A stepper motor requires two digital inputs, the first tells the motor which direction to turn and the second instructs to motor to move a single step.
  • DC5V from the Leetro becomes +5V on the Ruida, this is the upper voltage level for the signal.
  • PULX/Y/Z becomes PUL on the corresponding X/Y/Z connector
  • DIRX/Y/Z becomes DIR on the corresponding X/Y/Z connector
With the X,Y and Z connectors switched over it would be possible to drive the axis on the laser but it's best to add in the limit switches for the next step. These need a little bit of rerouting to connect to the new controller. When remaking the wires it's useful to have a wire end crimp tool, this allows you to put ferrules back on the wires, keeping it looking professional.

The Leetro controller has 3 wires for limit switches but most aren't used anway
The leetro controller only really uses two wires for each axis, one goes to the limit switch and one returns from it. It doesn't really matter which way round these two go but they are consistently coloured with blue as GND. There are several other wires but these are technically redundant for both setups.

The Leetro controller has the Z+ limit and the Z Origin connected to the same switch
The Ruida controller doesn't have the Z Origin so only the Z+ limit is connected
On the Z axis the green wire for ELZ+ was removed and the label switched to the remaining brown wire.
  • GND from the Leetro becomes GND on the Ruida, this is the base voltage level for the electronics.
  • ELZ+ becomes LmtZ+, this signifies when the Z axis has reached it's limit switch

A common GND signal for both the X and the Y axis
The X and the Y axis follow a similar convention, all of the extraneous wires were removed. CN4 on the Ruida only has one GND connection though so the GND wires for both the X and Y were routed into this pin with a new ferrule connector. 
  • GND from the Leetro becomes GND on the Ruida, this is the base voltage level for the electronics.
  • ELX- becomes LmtX-, and relates to the min X position and origin point.
  • ELY- becomes LmtY-, and relates to the min Y position and origin point.

That is all of the wiring required to make the laser cutter functional again. I powered up the laser cutter in stages, deliberately leaving the laser power connector disconnected until I was sure that the XY and Z axis were functioning properly and moving the right amounts. In the next post I'll talk through that process and some of the minor kinks I discovered along the way.

by (Unknown) at 04 January 2019 10:04 PM

03 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Last Minute Christmas Gift - Ring Keeper

Christmas is a very relaxed affair in our house, we used to run around between in laws but now we just head to some local friends for the day, this means we get time to play with presents and do things like making last minute gifts. I held out hope right until Christmas eve but Kim's present just didn't arrive so I took the opportunity to make it myself on Christmas day.

This necklace is actually a ring keeper, you can hook a wedding ring over the necklace without actually taking the necklace off (check out the video below). It's made from 2 layers of 0.8mm ply, glued and sanded so it's only 1.5mm thick but it's strong enough not to break, it actually has 6 layers of birch in that 1.5mm. The ring keeper idea was inspired by Morag Hickman and the clasp inspired by Shiny Shiny (svg here)

by (Martin Raynsford) at 03 January 2019 10:39 PM

02 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Load Spreaders

Sometimes I find it hard giving all the widgets and doohickeys meaningful names. I like Christmas foil decorations but this year I've been struggling to keep them hanging from the ceiling, they just keep pulling through the blu tack. Most things can be fixed with a laser cutter though, literally 90 seconds of drawing and cutting and I now have a handful of gadgets cut from 2mm perspex scrap. The string from the foil wraps through the gaps in the disk and the whole disk presses into the blu tack. In theory this should spread the weight load and stop them falling off the ceiling. It's working so far.

by (Martin Raynsford) at 02 January 2019 08:19 PM

01 January 2019

Martin Raynsford hackergotchi for Martin Raynsford

Knife Boxes

My friend Duncan has started making beautiful hand crafted kitchen knives and he asked me to cut some boxes for him. He even sent me a base box to work with because time was short, I made a few tweaks and included a flip top lid on the top of the box and sent them back in time for Christmas. The wood was stained on both sides and I tried some different colours. All in all a very satisfying collaboration and I'm sure the next set of boxes will be perfect.

by (Martin Raynsford) at 01 January 2019 02:53 PM

23 December 2018

Martin Raynsford hackergotchi for Martin Raynsford

Leetro to Ruida Settings

The first step towards upgrading a leetro based machine is to acquire a replacement controller. I opted for the Ruida 6442G to make it the same as my other machine. I bought my controller through ali express from Cloudray, it's currently $266 USD for delivery to the UK it took 3 weeks to arrive and cost around £250 GBP once customs and duty had been paid on it. I would probably recommend buying it through cloudray ebay instead, it's £260 but it'll arrive within a few days. Cloudray is my current part supplier, they've been pretty good so far. A delay suited me nicely with the Christmas rush on fractal puzzles and other products.

The kit of parts as it arrived was very complete. The controller and the screen were protected with bubble wrap and anti-static bags. Other parts include two USB cables to go from the controller to the edge of the laser, one for USB sticks, one for the laptop connection. An Ethernet extension to go the the edge of the laser and all the screw terminal connectors for the internal parts. Additionally there is an Ethernet cable to go from the edge of the laser to the network and a USB cable to go from the laser to the laptop.

The internal USB cable is Type B plug to Type A socket which means you need a Type A plug to Type A plug between the laser and the PC. This is a personal bug bear as A to A cables are not advisable in the USB standard and can be looped back into itself in a USB hub and cause electrical problems, but it appears to be a fairly common laser connection. My laser only has one USB hole currently cut into the case so I'll be using it for the USB storage connection and temporarily connecting straight from my laptop to the laser using a 3m A to B cable (the same as it currently does). I'll buy a B to B extension when I get round to cutting out more holes and ultimately I'll be using the Ethernet anyway.

As mentioned previously it's a busy time of year and I wanted to minimise disruption to my workhorse laser so I found a separate 24V power supply and connected the controller and display on my workbench. This allows me to communicate to the controller, through the USB, from my laptop so I can configure the system before I connect it to my laser. Because this is a machine upgrade I already have the machine settings in my Leetro configuration files, it's just a matter of matching the two things up. 

X and Y Axis Settings

The X axis settings are the easiest place to start. 
  • The maximum travel of the axis is something you should already know, in this case 900mm. 
  • The step length is the same as the pulse unit and it is the distance the axis travels in a single laser step.
  • I prefer my laser cutter to 'home' to the zero position upon start up so I've ticked enable homing.
  • The direction polarity should be true, to ensure that the laser moves to the right hand edge when it's trying to 'home'.
The other settings may not exactly have direct equivalents but the figures can at least be used for guidance. The Ruida controller splits into two sets of speeds and accelerations, these are for when the machine is doing work or for when it's being driven manually, in which case it can be a little faster and less accurate.
  • The maximum speed would be equivalent to the quick speed and determines how fast the machine can move. On the leetro this was set to 200mm/s and this value refers to both axis, I've set it to 350mm/s on the Ruida because it only refers to the lighter and faster X axis.
  • The maximum acceleration is set to 700mm/s^2, this would equate to the work-acc on the leetro machine which used to be 500mm/s^2. I'm keen to see how well the machine copes running slightly faster.
  • The jump off speed is how fast the laser moves when it starts, if this is too high you get a big 'clonk' as the head tries to go from stationary to moving instantly. I've copied the start speed value, of 3mm/s from the Ruida controller.
  • There is a second set of Jump off speed and acceleration values, these refer to the axis speeds when moving the laser manually using the keys on the keypad. I've kept them the same as the other values, the big difference between the Leetro and the Ruida is the slow speed control when moving the laser manually, the top speed is already fast enough for me.
  • The E-Stop acceleration refers to how fast the laser slows down and stops in case of an emergency. I left this with the default value, I'm used to the Leetro coming to a dead stop, skipping steps and ruining your workpiece in an estop scenario, if the Ruida comes to a managed stop then it's already an improvement over the Leetro.

The Y axis settings are going to be very similar to the X axis, on the Leetro controller they share the same values. I've taken the liberty of setting up X and Y slightly different on the Ruida. The Y axis has more mass because it has to move the X axis around, I have set the maximum speed and acceleration to closer to the original values.

Z Axis Settings

The Z axis has similar settings to the other axis but much slower, the Z motors have to move the entire bed up and down so can't achieve the same top speeds. The Z axis on my old machine has always been quite clunky and jumpy so I'll take this opportunity to adjust the values. The acceleration values on the Leetro controller don't really add up anyway, if you hold the keypad down the laser moves into a fast speed
  • The Z axis on my machine can drop down 400mm into the machine body.
  • The Z axis start speed is much higher than the other axis, that's probably what makes it clunky. I've dropped this down to 1mm/s, I also reduced the top speed to 8mm/s.
Empirically these changes to the Z axis make it seem a little slow but if I use Lightburn to drive the Z axis I can specify a distance to go. I'll only be using the keys to go up and down short distances while I manually focus the laser and I can use the Lightburn controls to go down further if I want to engrave on the top of a box.

Cut and Engraving Parameters

Lasercut 5.3 has settings for cut and engrave parameters but they don't really match the Ruida settings. They refer to things like corner acceleration and ranges of engraving accelerations. The Ruida settings appear to be much simpler but I assume the controller works out the more complex values from these simple inputs. I took these settings from the previous X and Y settings and a combination of the default values.

That's as far as it goes for setting up the controller without attaching it to the machine. There were a few other changes that needed to be made once it was connected to the machine but at this stage the controller is ready to be attached to the laser cutter. In my next blog post I'll talk about wiring this thing up to the the machine and occupying the place of the Leetro controller.

by (Martin Raynsford) at 23 December 2018 09:34 PM

21 December 2018

Martin Raynsford hackergotchi for Martin Raynsford

Lightburn Software and Ruida Controllers

Over the last year there has been a steady rumbling in the laser cutting communities and significant amounts of love being voiced towards a new piece of software on the market. Lightburn is layout, editing, and control software for your laser cutter. It's software that talks directly to your laser cutter and replaces the slightly dubious and buggy software that the controllers are shipped with. It's in very active development and all the reviews are good, it got to the point where I could no longer ignore it and I felt I should check it out.

Initial investigation of the screenshots show a familiar interface, all well polished and functional. Lots of additional buttons compared to the standard Lasercut 5.3 interface I'm used to. It appeared to have better control over the laser cutter itself as well as support for material libraries, camera control and sensible move functions. It imports svg files directly, so no more faffing around converting to dxf first and there is a free trial version so you can make sure everything works before you commit to a purchase.
With all these good things going for it, you may be wondering why I haven't been using it all year. Well there is only one minor drawback, it does not connect to the Leetro controller. There are a couple of commercial projects that talk to the leetro controller and even an attempt to reverse engineer the software but most of these projects seem to have stalled and Leetro were never exactly helpful when we had problems with their system so I suspect it may be some time,if ever, before Lightburn can include it in their list. All is not lost though, the MPC6535 is an obsolete controller anyway and there are much better options available.

If you rely on a laser cutter for your day to day business, the idea of taking it out of action just to test a new controller is a little bit daunting. Every few days you'll have to put the old one back in to clear your workload. You may remember that in September I started importing these new machines for people. These machines came with a Ruida controller, as requested by me, and that finally allowed me to check out Lightburn for real and I was totally blown away. 

The software starts with a familiar feel, allowing me to quickly set up layers and operations for cutting. Sending them to the laser was easy and I was cutting in no time at all. I ran into a little bug with the calibration of my new machine which caused the engraving to be misaligned and it took me just a few seconds to find how to fix it in the support documentation. Lightburn is fantastic and I'm definitely sold, all the new machines after that have been imported with Ruida controllers.

It should be noted that Lightburn isn't solely responsible for vast improvement on the new laser. The new machine was totally built for speed with an RF tube so the hardware is significantly better. The Ruida controller is also significantly better than the Leetro controller, the colour screen and UI makes controlling jobs and operation much easier (no more pressing the esc key before using the keypad). Lightburn is the front end of the system, it's the piece of software you use all the time and it is good.

It might seem unfair that I'm comparing my old laser running Leetro\Lasercut against my new fancy system running Ruida\Lightburn but this blog post is really just an introduction to a series of blog posts. I liked the new system so much I decided to upgrade my big old machine too and like most of my projects I thought it would be sensible to bring you all along for the ride.

by (Martin Raynsford) at 21 December 2018 08:56 PM

19 December 2018

Martin Raynsford hackergotchi for Martin Raynsford

Flip Card Score Board

Bit of a semi complete project this one but it was something quick I did this morning. A friend wanted a score card flip board, 5 rounds, scores 1-10. I knocked this set together and looped in some number cards quickly to show it functioning. The cards will ultimately be laminated and I don't have a laminator so it's been sent out with printed number sheets to be cut and laminated at the other end. Hopefully they'll do a better job with the hole punch than I have done here.

by (Martin Raynsford) at 19 December 2018 08:21 PM

14 December 2018

Martin Raynsford hackergotchi for Martin Raynsford

Cake Stands

Another cake related request, I made a set of three plastic cake stands of various heights and diameters. I didn't photo the other because they were still in the protective plastic. As you can see, these all had a scout theme using their fleur de lis logo. The tabs for the verticals were cut in the wrong place so the whole thing has to be wedged together slightly but this has the advantage that, once together, the stands are very sturdy.

by (Martin Raynsford) at 14 December 2018 11:22 AM

13 December 2018

Martin Raynsford hackergotchi for Martin Raynsford

Trumpet Toppers

I made this trumpet and cornet cake toppers by request this week. They're scaled appropriately to each other and cut from Gold and Silver mirror acrylic. Only the trumpet will stand upright in the cake which is why it has the additional spikes (both still have their protective cover on for posting).

Sorry it's been a bit quiet around here recently, I've had a busy month with Christmas orders and Craft fairs. I keep meaning to write some more technical articles but it's tricky finding the time, hopefully the new year will bring some new enthusiasm, I have plans.

by (Martin Raynsford) at 13 December 2018 08:39 PM

05 December 2018

Martin Raynsford hackergotchi for Martin Raynsford

Cosplay Stencilling

I was contacted to make some stencils for fabric painting, much the same as this super massive stencil. These are just A4 sized test pieces with an intricate triweave pattern and a diamond pattern. I believe they may be destined for a Batwoman cosplay.

by (Martin Raynsford) at 05 December 2018 02:26 PM

18 November 2018

Martin Raynsford hackergotchi for Martin Raynsford

Node Trackers

Another build for 'From Shadows', this time they wanted a device that could be used to track down other devices scattered around the field. I came up with a solution that used the ESP8266 to create a wifi network (nodes not shown) and these gadgets that scanned for wifi networks and reported the RSSI. The closer you are the stronger the signal strength and you know you're heading in the right direction.

The gadgets were supposed to have a modern mystical feel so I made them from fluorescent perspex, the sheet was sprayed with black and the details cut through. The whole front panel was lit from behind with UV led's so the glow only shone through the cuts. I also felt it would be good if the gadgets had to be held in both hands, under the thumb prints are two tactile switches which need to be firmly pressed to keep the device on. I think this might have caused a bit of thumb ache from the players while they were initially looking for the nodes, it certainly made taking a photo of the screen difficult.

The screens displayed information about the nodes being searched for. When the node wasn't in range the gadgets showed the internal time (this proved to be very useful as the gadget time drifted away from the real world time). When the nodes were in range the gadgets showed four 'readings' of mystical energy, but only at specific times of the day (hence the rtc). I think it worked moderately well, the batteries lasted the duration in both gadgets and nodes and readings were supplied at near enough the right times.

The whole thing was vacuum formed again for waterproofing and sturdiness.

by (Martin Raynsford) at 18 November 2018 08:32 PM

14 November 2018

Martin Raynsford hackergotchi for Martin Raynsford

Shield Unit

I delved into the realms of a Cyberpunk LRP system this weekend just gone. It was good fun and there was lots of opportunity to make techy objects for the game. This game featured airsoft weaponry so strength is another issue to consider The first item is a shield unit, energy shields take an hour to recharge once they've served their purpose. This unit times the hour for you, leaving one less thing to remember while you're running around doing everything else.

The unit is made from a mixture of acrylic and wood, the whole thing has been vacuum formed with a sheet of HIPS plastic to make it waterproof and robust to being shot. A large clip on the reverse makes it easy to attach to other pieces of kit (quite a lot of people wore military gear with lots of webbing/straps). The lower silver panel is actually a push button, it was intended to require a firm squeeze to operate to prevent it from being triggered accidentally. 

A rotating ring of blue LED's shows that the shield is in operation, one button push and the unit switches to orange recharging mode. In this mode the whole rings lights slowly over the course of an hour, when the ring is half lit then you know it's been 30 minutes. After an hour it switches back to blue rotating lights.

The unit is powered with a rechargeable battery bank, the batteries were tested before the weekend and managed to power the unit for a whole 72 hours so 48 hours at the event should be fine. Once home again it can be plugged into any USB socket to recharge it.

I didn't actually get any video of the final unit in operation but here is the prototype which will give you the idea.

by (Martin Raynsford) at 14 November 2018 12:02 PM

12 November 2018

Martin Raynsford hackergotchi for Martin Raynsford

Remote Controlled Wifi Strandbeest

I took these strandbeest kits to EMF camp, I blogged about them coming soon and I've been selling them at craft fairs and on my webstore. I just realised that I've never explicitly stated that they're available now. Get there while there is lots of time for Christmas, rather than two weeks before and we're all left hoping the postal service does it's job.

The kit features the ESP8266 micro controller so it's a great little project for learning about those. The device starts it's own wifi network and then serves up a webpage to your browser which you can use to steer the walker around. It's open source software so you can modify it as you require, but the Wemos D1 is supplied, tested and programmed, so even if you don't know anything about software you can make it work.

If you've already got a plastic kit then you can purchase the electronics on their own as an upgrade.

by (Martin Raynsford) at 12 November 2018 04:23 PM

Shut the Box

I've been doing a few craft fairs recently and wanted something a little bit more 'gifty'. These 'shut the box' games have turned out really well and have been a surprise hit with kids too. The concept of rolling a number on the dice and then flipping down a number of tabs equal to that total is very similar to the 'number bonds' they are being taught at school (7=1+6 or 2+5 or 7+0). The tabs have little pins that sit into the vertical bars and the lid works the same way with the walls of the box. They're up in my etsy store now

by (Martin Raynsford) at 12 November 2018 12:37 PM

03 November 2018

Martin Raynsford hackergotchi for Martin Raynsford

Long overdue cake parts

I found some images of some very overdue projects, these projects came in while I was in the middle of my kickstarter fulfilment and absolutely sucked up every last moment of my time. I even ended up taking a pile of parts on holiday with me just to get them completed in time, definitely a mistake I won't be repeating. It's a collection of 20 owl heads, and 55 remote control cars, 200 hours of work with a 4 week deadline, with one week on holiday and kids home for the holidays. :(

by (Martin Raynsford) at 03 November 2018 10:44 PM

Wine Bottle Gift Boxes

I had a local craft fair this weekend, I wanted to add a few extra/new items to my range so that my stall would be very different from last time. I've seen lots of variations on this wine box so I thought I would make my own version. The living hinges at the top allow the sides to be pulled close and the lid closed, it also a great place to put a handle. The fretwork patterns down the sides make them unique to me as well as the custom labels attached to the side. (svg here)

I didn't sell very many and I'm not sure any were going to be used as wine bottle boxes, one lady wanted to put plants in it and another was going to put fairy lights in hers. Neither wanted the the custom labels so I'm pleased they were only held on with blue tak. It's definitely given me food for thought with the next craft faire looming.

by (Martin Raynsford) at 03 November 2018 09:48 PM

28 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

The most wonderful time of the year

By which I mean Halloween of course, I seem to have missed a few of the previous years but now that the kids can carve their own pumpkins it was fun to do it again.

by (Martin Raynsford) at 28 October 2018 09:25 PM

27 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Beam Combiner vs Head Mounted

I've read a lot about the two different methods over the years and I've always had my own opinions about the subject but now I actually have two different lasers with two different red dot methods I feel like I can publically add something to the discussion based on my own experience.

The red dot on a laser cutter is a single point of light that shines down onto the work piece to show you were the laser cutter is going to cut. It makes it a lot easier to line up scraps of material with where the laser intends to perform a cut. Because the laser head is cone shaped you can technically predict where the laser will be and some of the really cheap K40 lasers do away with the red dot entirely, but I think it's always worth paying a little bit more money to have it included.

There are two distinct methods for putting a red dot on the work piece, the first involves fixing a small laser diode to the cutting head to shine directly down onto the material. Most of the affordable laser cutters (<£5k) appear to use head mounted red dot lasers. The laser diode needs power which means routing wires up to the cutting head but you should never purchase a laser cutter without air assist so there should always be a conduit to run the wires along. The diode adds weight to the cutting head which will reduce the maximum speed of the machine.

The diode is aligned by setting the correct focal height of the laser cutter and firing a test dot onto surface of some material, the laser diode is then physically moved until it points at that mark. The diode may drift over time but on your own machine it's easy enough to remember that the dot is a few mm to the left of the cutting beam. One of the advantages of this method is that the dot will move left or right as the Z axis goes up and down, because of this you can get a pretty good estimation of focal height by ensuring that the dot is directly below the air assist cone. Some laser cutters actually come with two separate diodes, when the dots are in the same location then the Z height is set correctly (at least until the diodes drift a little).

The second approach is to use a beam combiner, a 45 degree partial reflector lens is inserted into the cutting beam path, at this intersection a small red diode laser is shone into the beam path at right angles where as the main IR beam passes straight through the lens without being affected by it. The two beams then take the same path via mirror 1,2 and 3, down to the material. The whole unit remains stationary at the back of the laser cutter so it's easier to wire in and access. The laser head is simplified by only having to have air assist connected to it, it's lighter too meaning it can move faster for engraving.

Beam combiners seem to be the ideal solution and lots of people swear by them, there is an extra lens to clean but that is a trivial task and easily done with routine maintenance. The suggestion is that the red laser dot can be used to align the invisible IR beam but now that I've started using mine I would dispute that. The red dot actually led me into a false sense of security, because the red beam was right in the middle of the target area I concluded that the cutting beam but also be. When I took some time to actually investigate the system I discovered that the two beams were not perfectly aligned to each other.

The picture above actually shows five dots (I should have taken a picture of just the two). The red dot is obvious, the other four dots are alignment marks from the four different corners of the bed. As you can see no two dots are in the same position, the cutting beam is not aligned correctly and as you can see the red dot is not actually close to any burn mark. The red dot and the cutting beam still make it down onto the material so the assumption was that everything was working as intended. I aligned the cutting beam in just a few minutes (there are lots of guides online to help with that) but it took a further 20 minutes to get the red dot into the same position. The problem is that the red dot has to enter the combiner at the exact same location as the cutting beam as well as the correct orientation so that the beam follows the same angle. The red diode just isn't mounted well enough with enough adjustment to allow that to happen (a better bracket sounds like a future project to me).

My overwhelming feeling is that if it takes longer to align the red dot than it does to align the cutting beam then it's really not a very elegant solution. There is also a question about the beam combiner absorbing some power from the laser beam and if that effects the amount of power actually reaching the head (another future experiment I guess). That still leaves me on the fence which is a boring conclusion, it's probably best to work with what you have because it's a bit of a faff to change it.

by (Martin Raynsford) at 27 October 2018 07:56 PM

23 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Power in the apocalypse

In the near future I'm going to be doing a few more cyberpunk events so while it's probably a neon dystopia these things all share the same issues. Techno gadgets need to glow/flash/move or other things for a whole weekend in a place where access to electricity may be limited and changing batteries round all the time can be a pain.

I've recently picked up several of these USB powerbanks from Poundland (worth noting that they are £2). The teardown review was relatively positive so I thought it was worth a try. The first blinky LED project I've got running on it has currently been going for 48 hours non stop so I've made the decision to build one of these into the project rather than AA batteries (project details in due course). It's always worth designing with low power in mind and there are a whole bunch of tricks you can do to reduce the power consumption but I'm looking forward to getting these into projects.

by (Martin Raynsford) at 23 October 2018 02:08 PM

21 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Pancake Pawns

My friend Ed was making these pancake pawns on his 3D printer for sale on Etsy (not available currently). They're cute and he's got a wide range of them now so I wondered if I couldn't make something similar on the laser cutter which would be faster to produce. The laser cut version were definitely faster and had the option of adding colour but they're a little bit large and I never got round to shrinking them down to see how small they could go (The new laser would probably excel at the details though). It's another one of those projects that would go a lot further if I was actually interested in D&D myself :)

by (Martin Raynsford) at 21 October 2018 10:29 AM

18 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Second Hive Set

I made a second hive set for a friend, this time I used Indian Rosewood dye for the second colour. I like the colour in general and think it will make a great addition for my puzzles and other items. In this case though the colour is a bit too subtle (after sanding) and I would have liked something stronger. It's another nice set complete though and a gift for a friend.

by (Martin Raynsford) at 18 October 2018 07:00 PM

17 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Treasure chest upgrades

I have two different treasure chests for Vale, a small one where I keep all of my own personal resources and a larger one for the whole camp. There are 5 of each different resource but 6 different crystals, I built 5 sections across for crystals because the pure black kind were quite rare and had alternate uses (these were kept in their own box). Without going into two many details, the secondary use of these black crystals has all but gone from the game and now they are as common as the others so I have rejigged the layout of my boxes to make room for them. Thankfully the upper three crystal types are significantly narrow than the others so I was able to fit three rows into the space of two and the boxes remain nice and neat without significant revamping. 

I also took the opportunity to put a false flaw into the bottom of the big box. They're more common but we still only end up with 20 max and they never fill the section completely.

by (Martin Raynsford) at 17 October 2018 10:49 AM

16 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Wooden Boxes

I made some quick and simple boxes for Vale this weekend. They were designed to hold a few items at each of the nodes around site. The lid is slightly oversized to make them water resistant, which given the weather was a sensible idea. I decided to have a quick doodle on the lids though so that each one would be unique and because I love the way that line artwork draws on the laser I took a video of it doing it's thing. (I should really be doing this on the new laser but I'm still getting up to speed with it and sometimes it's faster to go with what you know)

I accidentally doubled up all of the designs when exporting to dxf and lasercut doesn't figure to point this out as a problem. I stopped the cut after 2 patterns and reloaded the whole thing. Each box lid had a little bracket in the corners to stop it from sliding off and wedge it into place.

by (Martin Raynsford) at 16 October 2018 10:45 PM

Iain Sharp

The Story of Pye Wireless

Bit of an odd one today – while helping my dad clear our some of my old books we found this pamphlet from 1986 – “The Story of Pye Wireless” by Gordon Bussey. I can’t find any other references to it on the web, and it seems well researched with some nice photos. So, to make it more widely available I’ve scanned it and made a copy available.

by Iain at 16 October 2018 07:26 PM

09 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Powder Press

EMF Camp always throws up lots of interesting opportunities and discussions. Apparently in the world of DIY cosmetics there is a shortage of presses for powder compacts. I laser cut a few samples from my acrylic off cuts with varying 'gap' sizes between the tin and the press. The downside to EMF is that I have no idea if these were actually any good for purpose but it was an interesting morning and discussion anyway.

by (Martin Raynsford) at 09 October 2018 09:23 PM