Planet Nottinghack

24 November 2015

Martin Raynsford hackergotchi for Martin Raynsford


A new project that I'm working on requires a two axis gimbal that holds the item in the stationary while the rings around it move. It's made from 3 layers of Birch ply with the middle layer placed at right angles to the outer layer to keep as much strength in it as possible. The whole thing can only be 9mm thick when flat so I had to embed the bolts into the middle of the wood (bit hard to see now) and the rotating side of the gimbal uses an acrylic insert to minimise the friction while rotating. It's definitely functional but needed a few more tweaks for my intended purpose.

by (Martin Raynsford) at 24 November 2015 11:09 PM

23 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Mini Bin with Lid

In a further development from the Agricola bins I did a quick test piece to see if I could make a lid for each bin. Games don't always stay the right way up and tokens can be flipped out of the bins, The lid sits in grooves that have been engraved into the sides. I was worried about weakening the sheet but it seems fine. Now I'm just wondering if it's worth doing for the whole box. (svg here)

by (Martin Raynsford) at 23 November 2015 11:06 PM

21 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

New Agricola Storage bins

Project #43 was Agricola storage bins, they were sold to someone who wanted them and I vowed to make myself another set. Of course if I'm remaking the set I might as well add some design revisions and then if I'm doing revisions I'm sure I can improve the layout and then I can make the boxes better and OMG that was over 2 years ago. So yes I have finally remade myself some bins, but I won't be getting too attached to these either because I know some people that want them already.

The bins were redesigned from the ground up copying the Linbin system I designed. The living hinge base panel makes it easy to scoop tokens out of each bin. I had to glue the boxes together to maximise the volume because space is tight in the box and I can't afford any dead space. I shrunk the middle row of bins and added an extra row to hold the square tokens. The playing boards go over the bins and stop the tokens from moving between bins and the Occupation and Improvement cards. The whole thing packs into the original box and the lid sits flat (very important design feature)

These bins are available for sale although it might be a few days till I get round to putting them in the store.

by (Martin Raynsford) at 21 November 2015 09:35 PM

Magic Santa Key

I was asked to make a magic Santa key, personalised for my friends children. Ta da. Not sure there's much else to say, it's 3mm mdf painted with metallic acrylics and it's a good job our kids aren't old enough to be reading my blog yet :)

by (Martin Raynsford) at 21 November 2015 12:22 AM

19 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

The new batch

Bit of a slow day today, few bugs going round our house and extra children after school, the only thing I managed to get done was this batch of fairy doors for the local school craft faire. I added a few new elements into the mix (mushrooms and stockings etc) and changed the blue out for purple. I've got enough elements now that no 2 doors will ever be the same which is a nice touch.

by (Martin Raynsford) at 19 November 2015 11:12 PM

18 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

More Gears

The laser is very good at whipping up a batch of gears for steampunk decorations. I've done gears before but it's actually quicker to draw new ones than the find the old files. (svg here)

by (Martin Raynsford) at 18 November 2015 04:34 PM

17 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

The wooden spoon

Last in request and completion. This spoon loitered at the bottom of the todo list so it's not a major surprise I overlooked it while doing the other trophies. It's a standard engrave for the logo and low power cut for the text, I am quite surprised at how well it came out though consider it is all a curved surface. Clearly a few mm in either direction of focus doesn't make a vast difference, I doubt the same could be said if I was trying to cut all the way through.

by (Martin Raynsford) at 17 November 2015 08:53 PM

16 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Double Wide Useless Machine 2.0

I was asked to sell a double wide useless machine, which I foolishly agreed to and then realised that machine was based on Version 1.5 and my machine is now up to Version 2, so I spent the evening bringing this design up to Version2.0 as well. It wasn't too challenging and it made me realise just how versatile this clip together box is, parametric design is definitely on my todo list now. 

by (Martin Raynsford) at 16 November 2015 11:44 PM

15 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Project #9 - Arcade Cabinet Complete

My gaming cabinet is now complete. I wired up all the internals and got the controller working (Pandoras Box 3 520 Games in 1). I was keen to get it all finished today so end up with a few more 'functional' decisions than I would have liked but now that the front bezel is in place and it's actually playable I can live with them for a few months.

There is a relatively large cable loom and clearly practice makes perfect on these things. Player 2 (left and controls) already looks better than Player 1. I re jigged the layout a few times but in the end was quite pleased with it. The system is run from an ATX power supply but I wasn't happy with the dozen empty cables floating around so I opened up the supply and cut out all the unnecessary connections leaving only the +12V, +5V and GND cables coming out the supply. 

All that was left to do was load up Donkey Kong and take a few working shots for the blog.

by (Martin Raynsford) at 15 November 2015 10:06 PM

13 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

War Gaming Trophies

So what was I squeezing out of yesterdays material, these 4 war gaming trophies. I've used a layered effect to turn the logo into a 3D trophy, the plaque is cut from silver/black HIPS and built onto a 6mm poplar base to make them stand upright.
The keen eyed amongst you may notice that trophies are for 2nd and 3rd places, there is a fancier trophy for 1st place but I promised to keep that under wraps until the 12th December when the tournament is held.

by (Martin Raynsford) at 13 November 2015 04:38 PM

12 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Maximising Materials

Due to reasons I cut the first of four items from a sheet of 3mm laser ply (instead of 2.7mm nominal). When I was looking through my materials I couldn't find a second sheet so I was left with the task of squeezing the rest of my cuts out of a sheet with holes in. In order to maximise the material I ended up drawing the sheet with approximations of the holes in it and then laying out the new cuts around those. Sure it would be simpler if I had a webcam in the lid to take a shot of the new sheet but this at least demonstrates it can be done the manual way. I've now got all the parts I need to assemble the other three items, all cut from the same material.

You'll notice that some of the sections are coloured. This is my trick for making coloured items quickly. Paint the sheet the desired colour and then cut the items out of it. Cutting the sheet out while leaving the frame in place allows me to quickly realign the sheets when they go back into the laser.

by (Martin Raynsford) at 12 November 2015 11:30 PM

NWSPK Chalkboard Erasers

In what feels like an eternity ago and delays entirely of my own making I ran these logo tests for newspeak house. Well tonight I finally got round to cutting 25 of the silver logos to be stuck on the back of chalkboard erasers, I think they'll add a nice little bit of class in a time when chalk boards just don't receive as much love as they used to.

by (Martin Raynsford) at 12 November 2015 12:00 AM

10 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Proxy Bases

Tonight I've made some proxy bases by request. When you have multiple models in close proximity during a match there is a chance they can bump into each other and become scratched. You can replace the model with one of these proxy bases that keeps track of location and angle for the model. I've also done some objective tokens and some flag markers (not pictured) to complete the set.

by (Martin Raynsford) at 10 November 2015 11:28 PM

08 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Christmas Baubles

After the impromptu maker faire badge I realised I could easily engrave some of Eli's drawings onto wood. He was dead excited that his drawings were to be immortalised in Christmas baubles and he drew me 6 images in circles using a thick black marker. A few minutes scanning and tweaking and 30 minutes etching time later and I had these nice baubles ready to make Christmas gifts for relatives.

by (Martin Raynsford) at 08 November 2015 11:23 PM

07 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Hershey Text Prices

 I wanted some price tags for my craft faire, as everything can be laser cut these signs were a prime candidate. The text was done using the Hershey Font Generator now included in Inkscape, it makes text as a series of single line strokes which has a very neat effect when cut on the laser.

by (Martin Raynsford) at 07 November 2015 11:13 PM

06 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Cat Stack

I made my own version of the Cat Jenga game that recently went round the webz. I cut myself all 24 cat shapes from that game and played my own cat stacking game. It's good fun and the cat shapes are great.

by (Martin Raynsford) at 06 November 2015 09:58 PM

Elf/Fairy Doors

I have a Christmas Craft Faire at the weekend, it's the active arts craft market in Countesthorpe if anyone wants to see me, so I thought I had better make something Christmassy to take along with me. Nichola suggested I make some fairy doors and it was a good idea, lots of places online for inspiration and lots of variety from a few simple pieces. 3 hours of drawing got me 12 different doors and a heap of accessories, 1 hour of cutting 1 hour of assembly. They came out so nice I cut a second set almost straight away. (svg here)

The panels were coloured before cutting to avoid a whole heap of fiddly painting. I even got to use my linbins to hold the different colours once they were removed from the laser. I even remember when just one item from these would take all day. It was nice to get these done and out the way.

by (Martin Raynsford) at 06 November 2015 08:28 AM

04 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Captain's Log?

Star trek style Com badges for a group of friends who were also going to be playing Artemis. Instead of pretending to be Humans of Earth, they were the Citizens of Klunge and they have rather interesting shaped space ships. Maybe the next time you see the crew of the TNG ejecting their warp core at the last possible moment you'll have a little chuckle too :)

by (Martin Raynsford) at 04 November 2015 04:34 PM

03 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Fujitsu Boxes

The glueless box on my useless machine caught the eye of someone over at Fujitsu Digital who thought they would be good boxes to house his prototypes, a few discussions and modification later I ended up cutting several of these boxes for them. I keep thinking I should make a parametric file for the glueless design but everything takes time.

by (Martin Raynsford) at 03 November 2015 08:34 PM

02 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

The Real DMMF Maker Badge

Designed from this hand penned drawing of what the badge should look like, I lasercut 150 badges for the Derby Mini Maker Faire this year. The large block of text is simply outlined instead of engraved because it stands out better and is a lot faster to cut. The badge features a single row of engraving (even when all 8 badges are cut at once) because this reduces the amount of time to cut. All other details are simple line drawings or holes. Kitronik was kind enough to donate all the Birch ply for the project.

The more observant amongst you will notice a code on the badge (1=S), because the badges were cut in sheets of 8 at a time it was possible to make 8 different badges. Each badge contained a number and a letter and was used to create a code that the visitors could break. It encouraged interaction between exhibitors and makers and completed forms could be return for a chance to win a prize.

The code word was "Sorocold" which you can see from the lined up shot. It was changed on me at the last minute and I felt it lacked conformational bias, people who had completed it still weren't sure what the answer actually was. People seemed to be enjoying it though and it was nice to see people playing a game I'd designed (with some help from Graeme).

by (Martin Raynsford) at 02 November 2015 07:20 PM

01 November 2015

Martin Raynsford hackergotchi for Martin Raynsford

Project #9 - Arcade Cabinet Built

My arcade cabinet is nearly done, it's just waiting for the screen and bezel which involves me buying super skinny perspex (1mm and 2mm due to a mistake in the drawing).  It's made from 6mm Poplar ply, skinned with 3mm Poplar to hide the finger joints. The back door and the monitor cross brace are both made from 9mm poplar to give them a bit more strength. 

While I had the laser cutter cutting all the panels I used the opportunity to cut pilot holes for all the hinges and brackets and I also embedded the speaker grill between the layers so it doesn't have to have visible screws on the front.

The player panel and the banner are made from fluorescent blue perspex. The pattern was reversed and engraved on the back. The side panels were stained dark brown to make them look a bit more like real wood. The central panels were all wrapped with vinyl that has a carbon fibre pattern, the vinyl goes under the perspex which really makes the details stand out. Next thing I need to do is wire up the internals but for now all the laser cutting is done.

by (Martin Raynsford) at 01 November 2015 10:57 PM

31 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Retro Robot Love

Halloween means costume making and now I have 2 kids that naturally extends to them. Eli wanted to be a scary robot, I ended up settling for Retro robot because we have cardboard boxes and vinyl pipes floating around the house. Topped off with egg boxes, bottle caps and yoghurt pots, I wouldn't say this build was challenging, time consuming or detailed but I think that's the main selling point. Eli was dead keen to help at all stages and there was an awful lot of love for it once we were out and wandering around the streets.

by (Martin Raynsford) at 31 October 2015 11:16 PM

Laser cut Pumpkins

but probably not enough to satisfy @MarkPhelan, Just a quick Halloween silhouette to decorated the garage doors. A long chain of neopixels provides some changing colour back lights.

by (Martin Raynsford) at 31 October 2015 11:08 PM

30 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Continuous Autofocus Laser Cutter Hack

We were inspired by the Glowforge laser cutters ability to continuously autofocus it's z axis. A camera mounted in the head of the laser detects a laser dot being shone onto the surface of the material and from there it can determine how far the lens needs to be adjusted to set the focal height for the correct cutting distance.

The Nintendo Wii Remote has an optical camera in it that is used to detect up to four points of infrared light. The hardware automatically identifies these points and feeds back XY positions through a bluetooth connection. The cutting laser on a laser cutter is an infrared beam, as it cuts through the surface of the material there is a moment where it is reflected off the material and the Wiimote is able to detect the location of the cut. The location data is fed back to a laptop and by comparing this point against the initial 'in focus' point we're able to detect if the Z axis needs to move up or down and by how much. The laptop sends data to an arduino that is connected between the laser cutters onboard Leetro controller and the Z axis stepper motor driver. The Arduino controller is the same as we have used on previous projects to control the Z axis. The result is a laser cutter that has the ability to remain in focus throughout the duration of a cut.

The project was written using C# and Brian Peeks Wiimote Lib, which made it incredibly easy to connect to the Wiimote using just a few lines of code. The source is available here but be warned it is a horrible mess of gaffa taped code written for a project that could never be more than an interesting hack.
The problems:
  1. Our laser cutters move the whole bed up and down to adjust the focal height. There is a lot of mass to move and it gains momentum so it isn't able to adjust the Z axis as fast as required. This is why it's so noisy as it tries to keep up with the requested position.
  2. The camera in the wiimote is capable of detecting light sources 60 times a second, the laser cutter is not able to process this information fast enough so there is some lag between the height change and the actual movement.
  3. The Wiimote is only able to detect the focus height while the laser is actually cutting. If the laser stops cutting and moves to a new area with a different height then the system will take a second to adjust to the new height once it starts cutting again.
  4. The increased mass on the cutting head prevents the laser cutter from reaching it's top speed of 50mm/s, and even if it could the response time from the system would not be fast enough to cope with changes that quickly.
This is a great proof of concept hack for a focusing system like this. In it's current configuration it is impractical as a working solution but it certainly was fun making it happen!

by (Martin Raynsford) at 30 October 2015 05:54 PM

26 October 2015

Matt Little hackergotchi for Matt Little

8-Bike Pedal Powered Scalextric

No image

Every so often a project comes along that would have been the envy of my childhood self. This was one of those projects -  I was asked to build a 8 lane pedal powered Scalextric. This meant putting together Scalextric track designs and testing Scalextric cars.

I was really pleased with the end result, which was built within a 10 day timescale. This blog post shows the design stages.


by (Matthew Little) at 26 October 2015 09:33 PM

22 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Project #9 - Arcade Cabinet Sneak Peak

I am falling behind on this years large projects, I've been working on projects 9 and 10 simultaneously and although neither of them are ready yet this one is slowly coming together. I'm making an Bar top arcade cabinet for myself based on the Clarkcade cabinets. I just got the buttons into the front panel to see what it would look like while I'm waiting for some vinyl wrap (to hide those screw heads). 

by (Martin Raynsford) at 22 October 2015 02:35 PM

21 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Glowforge glowy thing

The Glowforge laser cutter is currently crowdfunding itself over in America. It looks like a good piece of kit and I'm particularly interested in the autofocusing Z axis so I signed up fairly early on. There is a section in the forums about things you'd make on the machine, I feel wood veneers are massively neglected for these low power machines so I made this nice sampler to demonstrate what can be done. This box is made from Poplar ply, with a Walnut veneer on the front. The lettering is made from Bamboo veneer, the whole thing was sanded and oiled to finish it off nicely.

Here is my referral link if you want to get yourself an extra $100 off the price of a Glowforge laser.

by (Martin Raynsford) at 21 October 2015 10:59 PM

Matt Little hackergotchi for Matt Little

Pedal Power Monitoring Workshop

No image

Cyclops Pedal Power, based in Leeds, kindly invited me to work with them on their pedal power equipment.

They wanted to record the power and energy from their three-bike set-up, and have a system that can be expanded for more and more generators.

We had a three day workshop based in the fantastic Pedallers Arms working on monitoring voltage, current, power and energy.


by (Matthew Little) at 21 October 2015 03:26 PM

Martin Raynsford hackergotchi for Martin Raynsford

Scary Mummy Hand Child Sized

Make has this fun project to make some spooky mummy hands for Halloween. I borrowed one of Eli's arms, wrapped it in masking tape and then cut it free again. They both loved it and it gave us something to do on a wet afternoon.

by (Martin Raynsford) at 21 October 2015 01:40 PM

20 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Penny for your thoughts

A quick and simple speech bubble to be held aloft in wedding photos. The inner paper is actually a mask because the bubble will eventually be chalkboard black with a white edge to make it stand out. Guests can then chalk on a new message as they wish. Sounds like a fun idea for wedding photos.

by (Martin Raynsford) at 20 October 2015 11:16 PM

19 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

What does the fox say?

My friend Steph does some wonderful pen and ink drawings which she posts up to Facebook occasionally. Somehow I missed this one way back in February but as soon as I saw it I knew it would make an awesome lasercut. The artwork is all hers, I just vectorised the lines, by hand, to create some fancy line art. Automatic conversion would make 1 line either side of the pen marks in the drawing and I knew it had to be a single line per stroke to look right.
It's made from 2mm ply wood, Mahogany and Oak and backed with 0.8mm birch, I think it would make a nice brooch. Next time I might do the chin in Oak too.

by (Martin Raynsford) at 19 October 2015 10:30 PM

18 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Wax not working

I was asked if it was possible to engrave Wax candles in the laser. So I grabbed a pillar candle from the nearest shop and whacked it under the laser using the rotary attachment. We gave it several attempts slowly turning up the power and down the speed and the answer is 'No' wax just melts and bubbles away without really engraving.

I'm sure if we have a silver or gold candle, those are only coloured on the top few layers and you could probably cut that away but plain colour candles don't work.

by (Martin Raynsford) at 18 October 2015 03:41 PM

Dominic Morrow hackergotchi for Dominic Morrow

maker faire, the european edition. rome 2015

If you are a serious British maker with a project you’d like to promote or commercialise or even if you Continue reading

by chickengrylls at 18 October 2015 09:22 AM

16 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Wave Pendulum 2

I was looking for an easier way to assemble my pendulum wave kit. I tried to hang each pendulum off of a rod, each pendulum is rigid along it's length which means no more difficult strings. One length of piano wire is run across the bridge and through each pendulum, the rod runs in a grove across the bridge.

20mm ball bearings were clamped into the pendulum as weights, the tear drop shape clips on from the bottom and holds the ball in place. The cut outs around the hole allow the ball to squeeze into the gap and be held snuggly while the pendulum swings.

As you can see the bridge still isn't strong enough for the weight of all the pendulum. The short pendulums also don't swing for long enough to complete a full cycle so it's back to the drawing board once again.

by (Martin Raynsford) at 16 October 2015 10:21 PM

14 October 2015

Spencer Owen hackergotchi for Spencer Owen

Ace adventures on Jupiter

So, before I dive in to this, a quick history lesson for those of you that aren’t fully up to speed on your rare 80’s vintage 8 bit computers.  In the beginning, there was Clive Sinclair, and he invented the Sinclair ZX80.  From the ZX80, the ZX81 and indeed home computing was born.  From the ZX81 came the ZX Spectrum.  Ok, so Clive didn’t invent these single handed.  He had a team working for him, which included Steven Vickers and Richard Altwasser.  Somewhere between the initial design of the ZX Spectrum and its launch, Vickers and Altwasser thought there was a better way to do things, and left to set up their own computer company.

Jupiter ACE (restored)

Jupiter Cantab was formed in 1982, and Vickers and Altwasser developed the Jupiter ACE.  This little computer was a weird mix of ZX80 (vacuum formed white case), ZX81 (black & white low res graphics, 3k memory) and ZX Spectrum (rubber keyboard, small speaker).  The one fundamental difference, however, was that it used FORTH instead of BASIC as it’s operating system.  FORTH was much more efficient than BASIC, and would revolutionise the home computer market…

Although history tells us it didn’t.  Cantab went bust after 18 months and was bought by Boldfield Computing, who went on to sell off the remaining hardware in 1985.  Approximately 8000 units were manufactured.

When I was offered an original unpopulated Jupiter ACE by John Fletcher, it was too good to turn down…

The PCB itself was typical of those from 1982.  All the tracks had been laid out by hand, with different size pads (depending on the stencil they had to hand?), solder mask on the underside only and no silk screen.  There was quite a big scratch on the underside, although this checked out to be ok, and the board was in otherwise pretty good condition.  Unlike the ZX81 or Spectrum, it used standard off-the shelf components (Except the ROM – more on that later)


The Jupiter ACE has 3k of RAM, (1k user space and 2k video memory) uses 6 2114 ICs, which are pretty rare now.  Luckily, John had a few of these spare.  I had pretty much all the other components, with Nottingham Hackspace donating a couple of 74LS logic chips and EPROMS and a small order to RS for the remaining items.  As a variation to the original, I decided to use chip sockets throughout – I didn’t need to be as penny-pinching as people were 30 years ago!


Getting hold of a definitive circuit diagram wasn’t particularly easy.  Several schematics exist, along with high resolution photos of original models – however, they all contradict each other in some way or another.  Most differences are fairly trivial, some are improvements and some, well, are just different.  I mainly went for info from Grant Searles website and instructions from a Hungarian rip-off of Grants info


After some of the essential bits were put together, it was time for a few tests


Even without any RAM installed, the video circuit could be tested.  By looking at the output on a scope, it was clear that video signals were being generated.  Below is a shot showing a couple of lines and the blanking signal.  Things were looking good!


The original Jupiter ACE used an 8k ROM comprising of 2 2532 4k chips.  These are nigh on impossible to get hold of these days, but have a very similar pinout to the industry standard 2732, although it requires a little modification to the PCB tracks.  It seemed a shame to have to cut these, but there really is no neat way to get around this.  The other problem I ran in to was that I could only find a copy of the ROM as a single 8k file.  I assumed it was simply split in half with 0x0000 to 0x1FFF on one chip and 0x1000 to 0x1FFF on the other, but couldn’t find confirmation of this.  (In case you’re using this blog for reference – that is, indeed, the case!)


Things didn’t work though.  The screen just filled with garbage!  I wasn’t sure if this was a problem with the ROMs I’d burned, the memory, any of the old components I’d used, my soldering or anything else.  After comparing signals with Johns fully functioning Jupiter ACE, it was tracked down to the clock to the CPU not being a strong enough signal to get through.  This is amplified by a transistor with a couple of resistors which is one part of the circuit that’s different depending which source you look at.  I fixed this with a small pot so I could tweak the gain to the sweet spot.


This gave me some success, although often only for a few seconds before the computer reset itself.  Much head scratching and logic analysing went on before this was diagnosed as a power supply issue.  I’d been using a ZX81 power supply, and this is rectified down to 5v by a 7805 onboard the ACE.  If I bypassed this and just fed a regulated 5v from a USB adapter in, it worked fine!


The modulated UHF signal looked ok on my TV, but I hooked up a simple composite interface, and this gives a much sharper picture.  So far, so good…


As you can see, the keyboard is made up of PCB tracks that need a metalised rubber keyboard to make the circuit.  Original Jupiter ACE ones are not available, and I don’t think I could put anything together that would both work and do the old thing justice.  So, instead, I’m working on something to offload the keyboard function to a regular PC keyboard.  Look for more posts on this as it gets done.

by Spencer at 14 October 2015 04:11 PM

13 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Make A Faire Badge?

I was asked if I could make the Derby Mini Maker Faire badges as shown in the attached drawing. I think I made a pretty good job of it :P

by (Martin Raynsford) at 13 October 2015 11:26 PM

11 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Logo Samples

I was trying out some logo styles for Newspeak house, I personally like the copper on black with the vine details done in a low power cut and a close second as the same in wood but then I'm a stickler for fancy wood. 

by (Martin Raynsford) at 11 October 2015 09:46 PM

10 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

MAD business card holder

Warning title may be misleading. Sure it's just a regular business card holder but it has been installed in the MAD (mechanical art and design) museum. The guys over there just bought their second laser cutter from Just Add Sharks and the have installed it right in the museum so they can show people the laser cutting process (If anyone goes please take a photo for me because I forgot). They wanted something from us to hand out to interested potential customers so I made this little business card holder for them and filled it with our business cards. It's a little bit mad because it has a big magnet hidden in the bottom which prevents the holder from being knocked off the machine by accident (this we have learnt the hard way during maker faires.) (svg here)

by (Martin Raynsford) at 10 October 2015 07:03 PM

09 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Pendulum Wave (Test)

Ever since the Manchester Makefest this year I've been working on this project in my spare time. I made this pendulum test shortly after. This is a scientific demonstration known as the pendulum wave, each pendulum has a slightly different length so they all swing with different time periods and this creates a neat wave effect. There is a toy already available for this demo but I'm told that it's a pain to get all the string at the right length and that the kit could be better.

I took a shot at my own kit. I built a frame to aid with construction, with the pendulums at a fixed distance from the cross bar it should be easy to get the strings at the right lengths, right? It was definitely worth a try and although setting the strings was relatively easy the whole stringing process was actually quite tedious. The frame was rather insubstantial too and couldn't really take the weight of the all the pendulums. I used a long clamp to strengthen the bar to see how it all worked and I took the video below.

So why am I telling you about a failed design for an interesting kit? I've taken 2 more shots at this kit and details of those will follow but both have been failures. It's eaten up a lot of time and hasn't really got me any closer to figuring out how to make it work so it's up for abandonment. If I'm going to stop development on it I might as well get a few blog posts from the work done so far.

Pendula held in the framework to get the right string lengths
The whole flat pack kit

by (Martin Raynsford) at 09 October 2015 07:38 PM

08 October 2015

Tim Marston hackergotchi for Tim Marston

Using a shell in Emacs

Emacs Pumpkin

Emacs rocks.

It’s true, it does.

Recently, though, I’ve been trying to streamline my use of the shell in Emacs. Here’s my Halloween Emacs tips.

Added support for multiple shells

The first, glaring problem with shells in Emacs is that you can only have one.

I added a function that creates a shell based on the remote host of a buffer. It also names the shell after that host, so if I’m working on /, I’ll get a shell called ** (instead of just *shell*). This allows you to have multiple shells open simultaneously, one per host. [Credit: EmacsWiki]

(defun my/shell (&optional buffer)
   (let* ((tramp-path (when (tramp-tramp-file-p default-directory)
                        (tramp-dissect-file-name default-directory)))
          (host (tramp-file-name-real-host tramp-path))
          (user (if (tramp-file-name-user tramp-path)
                  (format "%s@" (tramp-file-name-user tramp-path)) ""))
          (new-buffer-name (format "*shell:%s%s*" user host)))
     (shell (if host new-buffer-name buffer))))

Added F9 shell toggle

Then I added the F9 global key binding to toggle between the current buffer and the related shell for the current buffer’s host, creating that shell as necessary.

(defun my/shell-toggle (&optional buffer)
  (if (string-match "^\\*shell[\\*:]" (buffer-name) )
      (my/shell buffer)))
(global-set-key [f9] 'my/shell-toggle)

Handle shell termination

There are several ways you could handle terminating the shell. You could, just for shell buffers, turn off the prompt that asks you if you’re sure you want to kill a buffer with an active subprocess running in it, and then use C-x k. But this would kill bash rudely, and bash would not save your command history. You could tell bash to save command history after every command. But this leaves executed commands between different shells all intermixed in the history file and shells would no longer have their own individual session history. That doesn’t appeal to me.

So I opted for another method: detect when the shell terminates and close the emacs buffer. This way, you can hit Ctrl-D (same as you would in a terminal window), bash saves its history, and everyone’s happy.

(add-hook 'comint-exec-hook
          (lambda ()
            (set-process-sentinel (get-buffer-process (current-buffer))
(defun my/shell-process-sentinel (process state)
  ;; show shell status and kill the buffer automatically
  (message "shell: %s" state)
  (if (or
       (string-match "exited abnormally with code.*" state)
       (string-match "finished" state))
      (kill-buffer (current-buffer))))


by edam at 08 October 2015 11:11 PM

Martin Raynsford hackergotchi for Martin Raynsford

Fancy Plywood and Interesting Designs

Pay attention because this is gonna get link heavy. Chris Champion has been sending me files for a while now, he makes some pretty amazing cuckoo clocks usually out of 12mm Poplar ply (I'm honestly not sure why I don't have any photos of the parts on the blog yet). Chris wanted to make a special present for a friends wedding and he wanted to use some real woods to do it. The trouble is that my real wood source typically only supplies wood up to 100mm wide and this item is 300x300mm.  

At the same time I had just finished visiting Peter Williams from They do some amazing work with sublimation printing on fancy plywoods. They have to get the plywood made specially for themselves but Peter was generous enough to let me buy some of these materials from him, 600x400mm sheets, 3 ply wood, 2mm thick. He has Beech, Oak, Mahogany and Walnut. all really good quality. He also said he would be able to supply sheets for other people too if anyone was interested. 

by (Martin Raynsford) at 08 October 2015 09:27 PM

07 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Cardboard Gaming Tokens

Prototypes for a friend who is play testing a game and wanted something more substantial that paper cut outs. The tokens were made by colour printing labels and putting them onto greyboard before cutting the individual tiles out. It's another alignment trick and it was done in two stages. First the outline was cut, the sticker was applied and then it was put back into the hole before cutting the individual tokens out.

Cut the outline from the greyboard
Cut down the lable and stick it to the greyboard
Put the sticker back into the hole 
Cut the individual tokens out

by (Martin Raynsford) at 07 October 2015 08:49 PM

06 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Front Door Sign

I was walking home from school with one of the other parents, she was complaining that people didn't know where her front door was and keep going round the side of the house. 10 minutes later I returned with a sign for her, 250mm long and engraved from HIPS plastic so it's weatherproof. Lasers are awesome.

by (Martin Raynsford) at 06 October 2015 03:57 PM

Matt Little hackergotchi for Matt Little

Jo Fairfax Studio - Motor controller

No image

I've been working with light artist, maker and NESTA fellow Jo Fairfax, (of Jo Fairfax Studio) on an interactive wall prototype.

He needed to have control over loads of motors which all move circular disks a set distance.

I designed a stepper motor controller unit to control up to 12 motors. These can be repeated to produce very large arrays of stepper motors.

The final effect is amazing, as shown in the videos here.


by (Matthew Little) at 06 October 2015 01:44 PM

05 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Pepakura Hiro Helmet

This project was done in a rush at the beginning of July according to the time stamps on the photos. Eli wanted to go to a party dressed as Hiro so I quickly made up a Pepakura Helmet for him the night before the party. Some repainted knee and elbow pads and we're mostly there. The helmet was printed on our colour printer and then cut using the laser and a few alignment tricks. I have written an instructable about the process but it boils down to letting the laser cut a hole the same size as your item and then putting the item into the hole. This method solves most alignment issues. (instructable and all files here)

We're going to need a bigger Baymax

by (Martin Raynsford) at 05 October 2015 11:25 PM

04 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Big Knife Switches

Igor, throw the switch! Every evil genius needs a wall full of Knife switches to turn the various parts of the lab on and off. Big knife switches can be expensive though so I laser cut some instead. It's made mostly from 9mm Poplar all painted with metallic paints. I made a set of 3 for the machine, I would also like to go back and revamp it slightly to fit a microswitch into the central post so they can actually work as an electrical switch. In the meantime I'm sharing the file in case someone else wants to do it before me (svg here)

by (Martin Raynsford) at 04 October 2015 09:49 PM

03 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

5 Point Iris

A second mechanism for Vale LRP and another file that has been floating round the internet. This Iris is a neat piece of engineering that has been built by dozens of people. I rejigged it slightly to put some better gears around the outside but other than that it's the same. Instead of using nuts and bolts to hold it all together it is all made from wooden parts, each pivot point is made from a 6mm wooden dowel. (svg here)

by (Martin Raynsford) at 03 October 2015 08:00 PM

02 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Non Circular Planetary Gears

I needed to make a dohicky for Vale LRP and I wanted something quick and easy so I trawled the net and found these non circular gears of Thingiverse. A bit of steampunking later and I had something neat that would fit into the genre. I've included my files here which are a bit of a mess but at least they will open in inkscape now (svg here)

by (Martin Raynsford) at 02 October 2015 09:36 PM

01 October 2015

Martin Raynsford hackergotchi for Martin Raynsford

Nottingham Theatre Royal in Cake

I recently helped Dawn from Dinkydoodle Designs create a cake for the 150 anniversary of the Nottingham Theatre Royal. The cake was presented to Prince Edward as part of the celebrations and he had the honour of cutting it. The cake was built in 2 halves and 5 floors, each floor had a baseboard (laser cut), built up with sponge cake and covered with chocolate ganache before the decoration and detailing went on. The floors were separated with cake frame to stop them squashing the sponge (now available from Lakeland plastics apparently). 

My involvement didn't stop with base boards though, once the basic shape was carved out I was called back in to wire the cake with lights. The front porch is lit, the chandelier and auditorium were illuminated with LED strips and the stage area was lit with a WS2811 strip and an arduino nano changed the colours every 10 seconds to give a sense of movement.

Here is a little video tour of the cake once it was opened.

The cake was built in 2 halves so that the internals were hidden until the cake was slid apart allowing people to see all the extra detail on the inside of the cake. Dawn has more photos of the cake on her facebook page here.


by (Martin Raynsford) at 01 October 2015 08:58 PM

29 September 2015

Martin Raynsford hackergotchi for Martin Raynsford

Project #8 - Catapult Range Finished

This project was remade from the first prototype and it was ready for my Cambridge workshop on the 13th, it's just taken me an additional 2 weeks to actually write about it. The principle is very much the same, I have fully enclosed the range with perspex to make it better at keeping the ammo in the range but also added a few other features.

This time I ran the strings over the top of the board. It was easier than worrying about routing the string past the braces on the underside of the board but also it allows the kids to see a greater connection between the levers and the targets. In Cambridge nobody asked what the levers were for so I guess it served it's purpose. The levers are now vertically mounted so that gravity pulls them down again, this makes the string slack while resting and the targets more likely to fall over. The targets themselves are now bolted to the base board rather than glued, this makes them nigh on impossible to break off with catapult shot. 

While in operation balls were getting stuck behind parts and we were having to remove the framework to get a hand in there and free parts up, I removed most of the natural ledges to limit this from happening and now balls only get stuck behind the targets. I made the rear third of the perspex screen an access panel. It can be lifted high enough to get a hand under and the balls can be moved as appropriate.

When not in use the catapult range is largely empty space, there is a big volume that could be minimised for transport and storage. The rear wall and lid can be removed, the two perspex side walls are hinged so they can be folded into the range. All the targets go flat so they aren't in the way. The whole range can be stored vertically and carried under one arm which should make it easy to get in and out of maker faires. Come and try it for yourself at the upcoming Derby Mini Maker Faire

by (Martin Raynsford) at 29 September 2015 11:31 PM

28 September 2015

Martin Raynsford hackergotchi for Martin Raynsford

Cake Building Layers

This is another large cake framework for Dinky Doodle cakes, This is taken from a floor plan of the theatre royal in Nottingham, each layer is a different floor of the building and it will be used to create the whole building from cake. The top layer is a roof because inside the cake the auditorium will be recreated with lights and a stage.

This is Dawns model of the cake that she cut by hand to show me what we are doing.

by (Martin Raynsford) at 28 September 2015 08:40 AM

27 September 2015

Martin Raynsford hackergotchi for Martin Raynsford

Fail and Fail Fast - Leetro Controller vs PAD03

Not every project can be a success and there is a popular mantra that you should fail and fail fast. You learn from failures and the sooner you get them out the way the sooner you can move on to the right ways. I don't have a lot of failures, I have a lot of projects that get put on hold until I know how to progress them, some of them are on indefinite hold at the moment. Tonight's project has been on the cards for a few months but it failed and relatively quickly so I thought I would write about it as I'm no longer working on it.

A lot of Chinese laser cutters come supplied with the Leetro controller MPC6515 or MPC6535, both use the PAD03 display panel to communicate information to the user. The system has a fair few quirks but the one that really bugs me involves the Z axis adjustment. You press 'Z' to move into the height adjustment mode but pressing 'Esc' does not get you out of the mode, you have to press 'Z' again. The idea is simple though break into the loop between the panel and the controller, catch the 'Esc' key as it is pressed and turn it into a 'Z' key press so that the controller leaves Z mode.

We know from the manual that the panel communicates via RS485 and at 9600 Baud using a Modbus protocol. There are a few modbus interpreters for arduino so I bought 2 level shifters to convert from RS485 levels to TTL levels. I chose the Arduino Mega because it has 4 hardware serial ports. The test set up has the controller connected to the Arduino on serial 1 and the panel connected to serial 2. The software just relays bytes from one serial port to the other but it also copies those bytes out to the PC so the data can be seen on a screen with a serial terminal. I had hoped to catch the text data being sent to and from the panel.

With everything connected and the data relayed back to the PC I turned the system on. Data was successfully passed through the Arduino to and from the controller, the system functioned normally despite the Arduino in the loop. Pressing buttons on the panel created additional data on the screen so it should have been easy to spot the key presses. I switched the panel into z mode and started pushing buttons. Only the 'Up' and 'Down' buttons were actually passed back to the controller, none of the other buttons were.

The conclusion is fairly simple. The panel understands that it is part of a laser cutter system, it's not just a dumb terminal reflecting information from the controller. It is the panel that switches the display into 'Z' mode and it is the panel that prevents it from coming out again. The project was a bust but I learned more about the system in the process and that is useful in itself.

by (Martin Raynsford) at 27 September 2015 10:46 PM

Kate Bolin hackergotchi for Kate Bolin

70sscifiart: The 1974 NASA Graphics Standards Manual (Get...


The 1974 NASA Graphics Standards Manual (Get your own copy from this Kickstarter for $79)

27 September 2015 03:00 PM

Martin Raynsford hackergotchi for Martin Raynsford

New Catapult instructions

The catapult has been around for a long time at various scales and versions, I recently sold a dozen to someone for a wedding and realised that the instructions were lacking a little. I redrew them attempting for a new words Ikea style, they're not as clear as they could be but I think they're acceptable and I'm pleased with the artwork anyway. (pdf here)

by (Martin Raynsford) at 27 September 2015 08:27 AM

26 September 2015

Martin Raynsford hackergotchi for Martin Raynsford

More Wargaming Tokens

I get to learn a lot of new things when writing these posts. There is a miniatures game called Guild Ball where you take control of a medieval football team playing/fighting an opponent to score goals. These tokens help people measure distances and keep track of movement, damage, hit points etc. They were cut for a friend who runs a Guild Ball Podcast which is apparently full of useful tips and crude language.

by (Martin Raynsford) at 26 September 2015 08:07 AM

16 September 2015

Martin Raynsford hackergotchi for Martin Raynsford

100 Pint Glasses

Been a very busy 2 weeks hence the lack of posting, but like always I've actually been making a whole tonne of stuff. I'll start with these laser engraved beer glasses. There is a micro brewery in the unit next to ours at Just Add Sharks. I engraved one on the laser using the rotary attachment and they decided that they would like a hundred. At 5 minutes for each glass this gave me a whole 10 hours of fun changing the glasses over all the time. I would say 100 is just about the limit for mass production engraved items, any more and there is probably a cheaper/more efficient way of doing it. 

by (Martin Raynsford) at 16 September 2015 11:26 AM

07 September 2015

Martin Raynsford hackergotchi for Martin Raynsford

Vale Quarry Map

Another map of vale, this time for the organisers to keep. This one is etched onto a beech veneered plywood, the same material as the star was cut from. It's 600x600mm  and 6mm thick, I rounded all the edges to make it nice to handle.

by (Martin Raynsford) at 07 September 2015 09:57 PM

06 September 2015

Martin Raynsford hackergotchi for Martin Raynsford

Project #8 - Catapult Range Prototype

I'm falling behind with projects, possibly due to having 3 maker faires and 1 LRP event in a 5 week period meaning my August disappeared. This was a spur of the moment project for Brighton Mini Maker Faire at the weekend just gone. It went well though and the kids really loved it so it's now undergoing a complete redesign to make it stronger and sturdier, which I'll need in time for my Cambridge Hackspace workshop next weekend.

I've taken my mini catapults to maker faires for quite some time now but they tend to get overlooked especially when we tell kids not to fire ball bearings at us. This time round I thought it would be cool if we had something they could actually shoot at, we could then cut mini catapults on the laser and hopefully sell a few more of both. I built a small range on a slope with 10 targets to shoot at, the idea being that the balls would roll back to the kids and a small motorised mechanism would stand the targets back up again. Testing and construction was swift and I had most of a range to take along with us to Brighton.

During testing at home and before I had designed the restting mechanism I noticed my kids loved to stand the targets back up again by hand. So instead of making the targets stand up automagically I decided to put in a row of levers with strings running over to each target to reset them. The string runs over the top of each lever and wraps around a bolt sticking out the back of the mechanism. This allows me to easily disconnect the string, pull it tighter and then reconnect it so that the tensions can be adjusted. The limited movement of the lever prevents the string being pulled too hard and yanked out of the target end.

Each target was affixed to a little hinge mechanism, the targets can lie flat against the board and the little lever on the front is enough to pull it back up again. this was quick and simple. To add a bit of variety the middle 5 castle targets were put onto a podium on top of a hill (also adds a bit of perspective and allows for a castle much smaller than the people)

The Ensuing Carnage
Brighton Maker Faire was good as usual and pretty busy (although maybe less busy than the previous year). We had children swamping our stall from the moment the catapults were working 10am until they called time at 5pm. The whole range took a battering and I learnt a lot about how these things are going to break. Most importantly it was a success and that is prompting me to remake the range.

  • MDF, this was probably my biggest error. when you glue 2 surfaces of mdf together the glue only sinks into the mdf a little way. If you put any serious force into this the mdf just delaminates and the whole thing comes apart. This was the fault behind, targets falling off, hinges being torn from the board and the whole 'hill' coming loose. The remake will be made from mdf, but all the joint will be made from sheets glued at right angles to each other.
  • Gravity. The balls are only 2 circles held 90 degrees apart so they don't roll very well. The slope could do with being a little stepper to encourage the return back to base.
  • Gaps. A massive mistake on my part, I forgot to close the gap under the hill so after the first wave nearly all of the balls were stuck under the hill. There were also ball sized gaps in lots of other places that should be eliminated, in front of targets were the worst because if a ball wedges there then the target won't stand up again.
  • Netting. The cage to hold the balls in was made from netting around a pipe framework. IT wasn't a particularly close fit to the board so balls were disappearing under the board all the time. Also every time we tried to move the cage it snagged on the board to it was a pain in general.
  • Balls. I took 50 balls, this was actually sufficient, I've probably got 30 left over. 100 balls would have been better though. It also would have been better to release them 25 at a time throughout the day, kids get through all the balls present super fast. Less balls just slows them down a little which is less effort for us to free them up etc.

New wood is on order, I've booked a slot on the Nottingham laser to cut all the bigger parts I require and I'm hoping to get this whole thing remade in just a week. Watch this space.

by (Martin Raynsford) at 06 September 2015 11:25 AM

04 September 2015

Kate Bolin hackergotchi for Kate Bolin

archiemcphee: German candy company Katjes has joined forces...


German candy company Katjes has joined forces with organic confection entrepreneur Melissa Snover to create a “The Magic Candy Factory”, a 3D printer that creates custom gummy candy. In addition to having an awesome name, the device enables users to design the gummy candy of their dreams using an intuitive iPad-based interface. The candy is heated during the printing process and then hardens as each layer cools to retain the 3D design.

“While the ingredients are confidential, Snover confirms the candies are lactose, gluten and gelatin-free, and entirely vegan. Delicious designs can be printed from seven different colors and 10 different flavors including mango, apple, blackberry, and extra sour flavors.”

Watch this video to see the mesmerizing Magic Candy Factory in action:

[via That’s Nerdalicious!]

Aw man, someone cleverer than I actually created the thing I was thinking about.

04 September 2015 07:37 PM

03 September 2015

Kate Bolin hackergotchi for Kate Bolin

This is Desert Fury, my new scarf, knitted in some beautiful DK...

Desert Fury, pretentiously draped over a Macintosh

Desert Fury, close-up

Desert Fury, before blocking, draped over a table

Desert Fury, as it is being blocked

This is Desert Fury, my new scarf, knitted in some beautiful DK superwash Merino called “Furiosa”.

Yes, really.

Wild Yarn Dreams posted this gorgeous yarn on Reddit’s YarnPorn, and I was instantly like GIMME GIMME YES.

It took me awhile to figure out what to do with it, but then I found the perfect pattern on Ravelry - Here Be Water Dragons.

This pattern is perfect - it’s complicated enough to keep me interested, but easy enough to do without having to repeatedly check the pattern, especially on the bus.  The yarn was so soft and beautiful to work with, the pattern went so smoothly, and it was an absolute delight to knit up.

I did change the pattern slightly - you’re supposed to repeat the main part 11 times, and I knew that’d use up all my yarn, so I just repeated it 5 times and had a little left over to make something neat.  And it still ended up being ridiculously long.  I blocked it on 5 of my 60cm square mats, and I thought that I’d have to pull out a 6th, so we’re talking 3 metres of awesome scarf.

This is definitely going to be my go-to for when I need to knit a scarf for someone.

03 September 2015 07:58 PM