Planet Nottinghack

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

08 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Edge lit badges

One of the EMF projects that didn't make it to completion were these edge lit badges. It uses a similar technique to my own EMF badge (black spray paint over fluorescent perspex) except this time the UV led and coin cell is built into the badge. The reason it didn't get to completion is because the led needs a hole all the way through the badge but the LED has to be covered otherwise the eye can't see the subtle fluorescing (the LED is too bright). The prototype used a piece of black tape but it's not exactly an elegant solution. I also tried to cut the whole first, then engraved through a black label over placed over the whole thing but I couldn't get it to cut clean enough.

by (Martin Raynsford) at 08 October 2018 09:01 PM

07 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Wedding Schedule Pallet

While I was making my wooden crates I ended up having a conversation with a neighbour about a pallet I was eyeing up. Turns out they were keen to make a Wedding Schedule Pallet but didn't know how they were going to burn the words on, laser cutter to the rescue. 

I ended up fashioning a whole new pallet from half planks, it was easier to cut some planks short to deal with the damage caused by plank removal. Each plank was sanded smooth (but not too smooth because I wanted to keep the rustic effect). Planks were masked with paper tape and then put under the laser. I tried two different lettering effects, the brown letters were simply engraved, the black letters were outlined and then spray painted black through the masking. In the end the plain engraving looked nicer. The whole pallet was engraved really quickly and as you can see the wedding was yesterday so I can post it up today :)

by (Martin Raynsford) at 07 October 2018 07:48 PM

04 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

My EMF Badge

I made a lot of different fluorescent coloured badge cases for EMF camp this year, I always like to keep some of the rarer materials for special people. I made these badge cases for the core team working on the Cybar installation. It's fluorescent orange perspex which has been sprayed with black acrylic paint. The laser then cuts through the paint and into the material so when the material shines under the UV lights the letters glow through the paint.

by (Martin Raynsford) at 04 October 2018 09:08 PM

03 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Access Point Configuration

A lot of my ESP8266 work creates a local access point rather than connecting directly to the internet so I thought I would release this source code that allows me to do that. It's a simple arrangement that opens an access point and creates a webserver. Once started you're able to change the SSID and Password for the access point from within the browser and if it all goes wrong you can revert to an open network with a known name with a few well timed button pushes. (source here).

A lot of my gadgets only use a local access point, I have this fear that if I gave the 'cake owls' full access to the internet someone will figure out how to hack them remotely and there will be a botnet of cakes before I can stop it. The devices also need to be user friendly because I can't assume anything about the technical skills of the people using them. The admin web page provides a friendly way to input a new SSID and Password for the network but. If the user forgets these values then the user can restart the device within a specific time frame (indicated by the on board LED) and the device will start a known network with no password.

There are several other wifi managers that allow the device to connect to home networks as well as start local access points but I needed reduced functionality for my own gadgets.

by (Martin Raynsford) at 03 October 2018 11:23 AM

02 October 2018

Martin Raynsford hackergotchi for Martin Raynsford

Hive Board Game

I've been meaning to make a set of Hive Game Tiles for some time, it's quite simple to learn and it's very portable. I intend to introduce new people to the game too so I thought it would be quite useful to have a brief movement hint on the back of each tile too. These tiles were cut from 9mm Poplar ply, stained mahogany for the red tiles and then sanded a coated with some acrylic lacquer. The first red tile was sanded back a bit too hard but once I made all the tiles the same I quite like the look. The insects are engraved and then outlined, the text is just a low power cut using a Hershey font. (svg here)

Each tile was sanded to within an inch of it's life using 800grit wet and dry paper, this makes some really fine sawdust that snuck into all the gaps of the tile. After becoming light headed from blowing the sawdust out of the gaps I realised that I now have an airbrush/compressor that can do that for me. I took a video of all the process too because it's quite satisfying to watch.

by (Martin Raynsford) at 02 October 2018 07:00 PM

28 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Laser cutter speed difference

Here is the video of my two laser cutters cutting the same tile side by side. It prompted a few people to ask 'how come the 30W tube is much faster than the 100W tube?'

I picked the new laser cutter based upon speed. It had a few specification stats that suggested it was fast and the photos showed a fairly lightweight head etc. Now that I have the laser in my possession I can see all the design decisions that make it fast. In the case of these Carcassonne tiles I only need the full power of the laser when I'm cutting the tiles out.

The low power engraving lines are done with minimal power, only 8% of the 30W tube. The metal RF tube gives me much more control over the low end power, the head can fly around at 100mm/s, twice the speed of the larger machine. The engraving can be done at 1000mm/s, again nearly twice the speed and empirical evidence suggests that it is actually moving at that speed.

The 30W laser can easily handle the 3mm poplar ply wood at a sensible 35mm/s, the 100W machine can do it at >50mm/s. I have to use the > symbol because at 50mm/s the laser head is moving at it's maximum speed, the laser power is only set to 50W. If the laser head tries to move any faster it will occasionally skips steps while moving and if the cuts are misaligned to the engraving the whole tile is ruined.

All of these tweaks make the whole thing a lot faster. The other minor thing I've been asked about is why I cut the grass blades before engraving the grass area. The laser beam is focused to the surface of the material, when I cut on the engraved areas the laser beam is slightly out of focus. Doing it this way round keeps everything nice and crisp. A secondary advantage is that the engraving takes away all the smoke marks made by the low power cut.

by (Martin Raynsford) at 28 September 2018 08:11 PM

27 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Laser cutter comparisons

I finally dialled in my new laser cutter this evening, I had some minor issues with the bidirectional engraving lines not quite lining up. I also spent some time testing out speeds and powers to see exactly what it's capable of, now I just need to figure out how to take better pictures in the evening.

The tile on the left was cut on the old laser cutter (100W glass, 600x900mm) and the tile on the right was cut on the new machine (30W metal, 300x500mm). Both tiles are actually very comparable, the 100W obviously makes deeper and darker lines. The engraving colours are close enough and with a little more effort could be identical. The 100W slightly breaks through the sheet on the corners where the head has to slow down to change directions. There are more cut marks on the underside but that's because the 100W honeycomb is filthy.

Even with these two tiles being so comparable there is one hugely significant difference. The old laser cutter cut the tile in 2 mins 13 seconds and the new laser cutter cut the tile in 58 seconds. That's over twice as fast, tomorrow I shall video a side by side comparison of the two cutting.

by (Martin Raynsford) at 27 September 2018 09:07 PM

25 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Mounting the Wemos D1 Mini

I use the Wemos D1 Mini for all of my wifi based projects, such as the remote control Strandbeest and the Stranger things light board. It's a powerful little board that exposes the ESP8266 via a USB to Serial converter and it can be set up to run from the Arduino environment. It's also really cheap and can be bought for less than $2.50 so if you want to make something remote controlled it's a bit of a no brainer. The trouble is that the board doesn't have any mounting holes so it can be hard to attach to a project.

While looking to affix my board securely to my projects I realise that there was a gap to the left and right of the ESP8266, either side of the antennae that didn't appear to have any copper or tracks running through the area. The board is only a 2 layer design so it should safe to drill directly through the PCB and use this as a solid fixing point. A quick test later on a sacrificial board showed that this was indeed possible and although adding screws next to the antennae may restrict the maximum range, the maximum distance I require is 25m and it seems to still run fine. I used a 2mm drill bit to make the holes and I routinely use M2 x 6mm machine screws to fix the boards to my projects.

Once some suitable mounting holes were identified I had the problem of drilling holes in dozens of boards for my kits. I've talked about jigs a lot before and this is no exception, making a jig to hold the boards in place and show me where to drill the holes is the best way to ensure each board will fit into any kit. It's also the fastest way to drill 100 boards in a single sitting.

I started off with a single board design, by flipping the wemos upside down and I can use the ESP8266 board and metal can to align it into the jig. This ensures that even if the ESP board is slightly offset the holes will still be equally spaced on either side of it. I scaled my jig to eventually hold four boards at a time, allowing me to drill more holes between changing boards over. I'm sharing the files for the jigs so that other people can drill similar mounting holes should they need them (svg here) (dxf here)

Here are some assembly photos for the 4 board jig, I added some feet onto the bottom using scraps of wood but I have now included some feet into the spaces cut from the jig.

by (Martin Raynsford) at 25 September 2018 01:34 PM

24 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Extractor fan cleaning

Given that I have to clean my extractor fan every six months I'm surprised that I can't find a post about it. There is a grill over the front of the extractor fan which clogs surprisingly quickly when cutting wood but this time round, cleaning the grill didn't seem to improve the extraction so I had to dig a little deeper.

Inside the extractor fan is a large impeller blade, this sucks are in to the middle of the fan and flings it out to the edges, it rotates around the edge of the fan and then out the hole at the bottom. The smoke contains vaporised wood particles which is surprisingly sticky, this coats every surface inside the laser and eventually reduces the efficiency of the fan.  

The impeller blade is held in with a single bolt in the middle. The motor shaft and corresponding hole in the impeller are 'keyed' so that they turn together. Do not lose this key when you take the blade out. With the blade removed it is a lot easier to clean up the blade and areas of the housing that are normally under the blade. I just ran a wire brush over everything until it looked clean enough. I hoovered the dust out at regular intervals.

As you can see once the whole thing has been cleaned it looks a lot nicer but more importantly it works a lot better. All that is left to do is close the fan back up and reconnect it all to the laser again. Next time I'm in the machine I'll get a picture of the external grill to show how quickly that clogs.

by (Martin Raynsford) at 24 September 2018 09:48 PM

18 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

New laser cutter

My new laser cutter arrived at the start of last week, I feel a little guilty for not posting it sooner especially as I've been teasing it on Twitter all week but here it is, in all it's glory in a single post.
It's a 500x300mm cutting area with a 30W metal RF tube. Everything about this machine is designed for speed and in quick initial testing I've managed to take it up to 1000mm/s and it seems to run fine without skipping steps.

The laser head is super light weight and the belts are nice and thick which helps to avoid bounce when changing direction.

Mirror 1 has a beam combiner for the red dot light, another bit of weight off the gantry.

Proper linear screws on the Z axis make for very smooth vertical motion and inductive limit switches on all axis to avoid mechanical wear.

Finally the laser itself is a 30W metal RF tube. There are a lot of websites which offer information about Glass vs Metal tubes, now I have both I can compare to see which is best.

by (Martin Raynsford) at 18 September 2018 10:26 PM

16 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Fluorescent Signs

Photo by Sophie Garrett
Saving my best for last were these signs that were mounted on the containers to indicate who was exhibiting inside them. They were engraved onto Fluorescent Acrylic so that the caught the UV lights positioned all around Cybar. My initial intention was to side light them with my own UV led strip but that didn't arrive in time so I was lucky that there was enough UV left to go round. The photographers clearly liked them too and there are some amazing shots floating round out there.

Photo by Mitch Altman

Photo by Phil Hutchinson

There were 6 signs in all, I could swear I've seen a 'puzzle hunt' image somewhere and my own 'chop shop' sign which didn't fluoresce quite as much as the others due to it being blue.

by (Martin Raynsford) at 16 September 2018 05:24 PM

15 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Central reservation barriers

Last on my list of big props for EMF Camp are these pair of central reservation barriers they're quite common in cyberpunk street depictions so I thought it would be cool. More Sheets of MDF were cut down to the right sizes, a jig saw was used to cut out the end angles. The sides were reinforced with pallet wood to give it strength, in case people decided to sit on them. The Polybius logo was embossed on each side using a router with a 45 degree bit. The paint effects were achieved by applying successive layers of grey paints with a paint scraper rather than a paint brush. The darker colour around the base was spread using a rag and wiped down to blend with the greys. Obviously the orange Polybius was added using spray paint and a laser cut stencil.

by (Martin Raynsford) at 15 September 2018 06:40 PM

14 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Making a spectacle of EMF

In the many glass cabinets at Cyberdog were lots of laser cut acrylic bangles and spectacles. I thought it would be cool to make some of these things up at camp but in the end I spent the whole time cutting badge cases (literally 12 hours a day). I did make this one prototype though which somebody loved enough to take home again. The arms were bent using a hot air gun, although I have done 'off focus' laser bending before it's definitely quicker doing it this way.

by (Martin Raynsford) at 14 September 2018 01:40 PM

13 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Faux Aircon units

Given that the Null Sector comprised of 10x 20ft shipping containers, there was a fair bit of scope for making some larger props to go in the area. A quick flick through google images shows various scenes of neon lighting and roofscapes adorned with pipework and units. I had the idea to make some faux aircon boxes to mount around the camp. As you can see some of these units crept into the back of shots and proved to be quite useful to cover up the name plates on the sides of the containers. 

Image by Sophie Garrett

The basic box shapes were made from 6mm MDF straight from B&Q, I spent a good 20 mins their annoying everybody else who wanted sheets cutting down to size but it's generally easier to pay a bit more money per sheet and have someone else cut it down into chunks that A) Can be assembled immediately and B) fit in your car. Some additional holes were cut on the laser cutter, it's a bit sticky as materials go but if you need a tri pronged hole quickly the laser cutter is a great way to go.

Fans and slats were made using the laser cutter and more traditional laser materials (the fan blades were obviously cut from the fan holes. Each blade was mounted to a central hub which set it at an angle but also housed a bearing, because of this each fan was able to spin freely in the casing once it picked up the wind. I definitely saw a few people who noticed this detail at the weekend.

All the units were painted grey with some cheap masonry paint. The fans and slats were given a second coat of shiny silver paint which was applied with deliberate streaking. The units really came alive though with the application of some rust effects. It was such a simple technique that really added character to the units and made them all very unique.

by (Martin Raynsford) at 13 September 2018 07:23 PM

12 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Rust in Pieces

With my recent builds for EMF camp I had an opportunity to try some new weathering techniques. My skills are a bit lacking and there is lots of conflicting advice/techniques online and my time was short so I went straight to Eldritch and Simon gave me some definitive answers on the subject of rust. I thought I'd write the info down here so that it can hopefully benefit someone else.

You will need.
  • White vinegar and salt, available from any supermarket and you probably already have them
  • Hydrogen Peroxide, available online or I got mine from the Boots chemist. They were unsure they even stocked it so it may pay to be a bit persistent and ask them to actually check the drawers. You'll be asked why you want it but when you have a legitimate reason like this the conversations are always fun.
  • Iron Powder, this is pre rust and not the same as Iron Oxide Powder (post rust). I bought 500g on ebay and now have about 450g left over. 
  • Super glue, I opted for a large bottle of high viscosity glue so build up the ridge effects. Always handy to have excess glue spare for other projects. 

Mix the vinegar and hydrogen peroxide together, I used a 50:50 mix and add a sprinkle of salt into the liquid. I decanted the mix into a spray bottle and filled a second spray bottle with water, this will be used for the super glue.

  • Apply a healthy does of super glue to the area you want to be rusty.
  • Spritz the super glue with water, this will cause it to dry with a texture effect.
  • When the glue is dry, sprinkle the area with some Iron Powder, it helps if the area is flat. When working at an angle I found that spray the glue with some acrylic lacquer helped the iron powder stay in place.
  • Finally spritz the iron powder with the chemical mix, this will start the rusting process. Once the area was sufficiently tarnished I sprayed the whole thing again with another coat of lacquer.

That was how I did my rust effects on the Aircon units and the Semiotic signs. I'm sure things could be done better and with a bit more experimenting it could be much more rust like but I was happy to find a quick process that covered large areas and looked great.

by (Martin Raynsford) at 12 September 2018 05:24 PM

11 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Glass cabinets of Fun

I wanted my container to look like a workshop/shop and sleeping area. I visited Cyberdog in Camden market and was quite taken with their rows of glass cabinets containing items for sale. Following on from David's assertion that Ikea is the only store that survives into the cyberfuture I acquired myself some second hand Detolf cabinets.

It turns out that flat packing and repacking cabinets is a bit of a pain and trying to transport 8 large glass panels in the back of a Luton van is a bit nerve wracking. The cabinets were packaged well with card and tied up to the railings to stop them falling over. They fit really well with the aesthetic and they served impeccably to display my kits for sale.

With my newly installed cabinets came the need to create display stands, having a laser nearby solves those issues though. I built a quick stand to hold all 4 different fractal puzzles vertically within a cube and I built some small price tags (always a good indication that stuff is for sale). One minor annoyance is that I lost all the screws on the way home but thankfully the amazing Ikea is sending me more fixings, once they arrive I'll be able to sell the cabinets onwards and break even on the whole cabinet adventure.

by (Martin Raynsford) at 11 September 2018 08:26 PM

10 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

EMF Camp Badge Release

It's finally here, the files and the back panel for the EMF Camp badge 2018. That officially took too long to sort out after EMF but I used all my plastic up at the camp and it took me several days to reconnect my laser this year. So, now the excuses are out of the way, I have completed a back panel and stand offs to go between the two. This panel holds the battery down securely and protects the antennae. (svg here)(dxf here)  I'll also put it on thingiverse

by (Martin Raynsford) at 10 September 2018 07:19 PM

09 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Semiotic Standard Signs

Once the semiotic standard was established and a few legends were scattered around the Cybar camp, it obviously made sense to put a few signs up on the containers. These were cut from Polypropylene and painted badly by hand (because it was faster than airbrushing). They only started to look like real signs once I had applied some rust effects and other weathering techniques. I'm particularly pleased of the rust and there will be more of that to come.

Signs were scattered all around camp and after pointing them out to a few people they seemed to blend in too well, people kind of assumed they were part of the containers anyway, which I guess is a good thing.

My favourite has to be the shots of the DJ booths in which you can clearly see the 'laser' sign on the doors just behind the DJ's. particularly apt given that they had nearly 100W of visible laser light amongst all of their machines. This photo was taken by Sophie Garrett and she has lots of awesome EMF photos over in her Flickr Album 

Photo taken by Sophie Garrett

by (Martin Raynsford) at 09 September 2018 05:29 PM

Semiotic Standard Poster

During the build up to EMF Camp I was sent a hand drawing of the Semiotic Standard, a series of icons used in the Alien movies. I thought these were wonderful and I just had to draw them out in vector format so that we could do something with them. Of course if I had spent less time drawing and more time looking I would have found loads of people who had already done the same thing but at least I had fun. 

Once I had recreated the whole thing digitally I had some glossy posters made for me by Braunston Print (5 stars for quality and service). These posters were put up in strategic places around the container village to add to the overall set dressing.

I almost forgot to share the file in case anyone else wants to use it (svg here)

by (Martin Raynsford) at 09 September 2018 08:35 AM

07 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Filling the cybar camp

In keeping with flavour props for the cyberpunk area, I made a handful of small items that could be quickly and easily scattered around the camp to make it feel more futuristic.

First I made half a dozen CCTV cameras, the regular participants of EMF camp are potentially wary of CCTV so these had to look plausible but fake. A simple perspex hemisphere over some basic camera shapes would suffice. The cameras were then 'destroyed' so they definitely look non functional.

Simple 'microwave' dishes were made on the vacuum former which allowed me to construct a whole network of mini antennae. Magnets on the back of these items which allowed them to be placed upon the sides of the containers quickly and easily.

by (Martin Raynsford) at 07 September 2018 07:40 PM

06 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Filling the pinboard

I had to fill the pinboard with details and I stumbled upon this amazing artwork by Vasily Khazykov, I borrowed a few of his print outs to go on the wall but I also wanted something a bit more physical to go alongside it. I chose a few items from the drawings that I could turn into physical props with a fast turnaround and I spent a day last week putting some parts together. As props they look a little bit wooden and I should really spend more time on finishing. As quick decoration pieces I think they definitely added flavour to the board.

I also made a spinning hard drive gadget which I totally forgot to take pictures of, you can just about make it out on the bottom of the board here.

by (Martin Raynsford) at 06 September 2018 07:11 PM

05 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

Tool wall and pinboard

In my workshop container for the weekend, I was keen to add some set dressing to the walls so the idea of a pinboard for projects and a tool wall were born. The pinboard is a simple framework outlined using some left over pallet wood which is why it has the nice scoop shapes. Laser cut brackets around the corners keep things vaguely square. The tool board was 12mm ply sheet I've had around for ages, I wanted to give it a nice graffiti style paint job so I put my airbrush to use in a variety of colours. It's the first time I've used my airbrush seriously and I think it came out ok.

The lettering on the tool wall was achieved with a lot of masking and painting of layers over several days, it was definitely a fun project and I really enjoyed trying lots of different style and techniques on a large blank canvas.

by (Martin Raynsford) at 05 September 2018 07:38 PM

04 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

EMF Camp prop making

picture by @JamesHarrison

This years EMF Camp had a large cyberpunk themed area featuring art installations, a bar, DJ and lots of other interesting things. It takes a lot to set this kind of thing up in a field though for a weekend, and the team pulled out all the stops to produce an epic experience. The 'Cybar' or 'Null Sector' really came alive at night time though when all the lights came on and the lasers and flamethrowers came out.

The base encampment was laid out using twelve shipping containers, the whole campsite was circled with security fencing with tarps making it hard to see inside the camp. Truss and scaffolding was placed along the edges of many containers and between containers allowing power and lighting to be run overhead and down into each container. A large metal dome was built in the open area and a 10ft container was stacked on top of another 10ft container to provide an elevated DJ booth. Once the basic structures were in place the whole area still needed decorating according to theme. I made a selection of props to go in the area which I'll detail over the next few days.

After some initial discussion about me running my laser cutter from the back of a Luton van the team was actually kind enough to let me set up a workshop in one of the 10ft containers. I'm a bit of a sucker for a theme and decided to go all out with my setup. For the basic 'workshop' aspect of the container I just took my laser cutter and some work benches but for the shop aspect I decided I really needed to get some Detolf glass cabinets from Ikea. A quick ebay find later and I managed to get hold of a pair of the worst possible furniture items to take to a field. 

I built a few other items to go inside the container, took my wooden crates and bar top, I also strung 1200 neopixel lights across the roof to give the whole place a nice glow. I'm pleased with how well my space turned out and the the whole area was a fantastic thing to be part of. The flamethrower on the roof of my container did a good job of keeping it warm. Because I was cutting badge cases I was pretty popular all day and all night so I was glad I made the extra effort to fall in with the theme.

by (Martin Raynsford) at 04 September 2018 09:53 PM

03 September 2018

Martin Raynsford hackergotchi for Martin Raynsford

EMF Camp 2018 badge cover

I just got back from EMF camp and I spent most of my weekend cutting badge covers for people. Sadly I forgot to take photos for myself and I've had to steal others from twitter.
Marneus chose the vibrant orange and riley had a yellow case, I also cut in Red, Green and Blue. I'll post some pictures once I've recut on of each at home.

If you failed to get a badge cover at EMF camp you can now pick one up from my store.
I will also be sharing the files too but I want to cut and test something and that means emptying my Van back into my garage before I can start again.

Dominic took the files and modified them to cut his own leather version on his laser

by (Martin Raynsford) at 03 September 2018 08:42 PM

28 August 2018

Iain Sharp

VCV Rack for EMF Camp 2018

I am running a beginners workshop on the VCV Rack moduler synthesizer simulator at EMF Camp 2018. Currently scheduled for 11.20 am on Sunday in Workshop 1. If you are at EMF Camp and want to join please bring a laptop and headphones.

Here are some resources for the event:


by Iain at 28 August 2018 06:42 AM

27 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

EMF Camp 2018 badge hacks

EMF Camp 2018 just released details about the badge for this years camp and it looks incredible as always (Hackaday has a great summary). It's a full blown smart phone which can be used on site using the local network or on a standard gsm network after the event. Like a lot of camp badges though, despite amazing innovations it's still just a bare circuit board dangling round your neck ready to short out against objects (like the metal of the laser cutter) so there is a bit of a need for a case to protect it.

I'm one step ahead of the curve this year and hopefully I've produced the first badge hack of 2018. I initially cut a nice wooden case to show off the fine details that a laser cutter can produce and then I cut one in florescent plastic to glow under the UV lights of Null Sector. Finally I realised I could patch into the 3.3V that is one the board itself to produce a fancy edge lit case (hard to take a good photo of it though).

If anyone is interested in getting a case for their own EMF Camp badge I'll have my laser cutter set up and running in Null Sector and I'll have a stock of surface mount LED's so if you can handle the micro soldering you can make yours glow too (I'll have a fine tipped soldering iron and all my other tools there too)

by (Martin Raynsford) at 27 August 2018 08:20 PM

26 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Scaling up to kit quantities

But firstly a divergence into glue.
I have a few kits available in my shop and some of them require glue for assembly. It's always been a bit of a sticky subject for me. I recommend Evo-Stik weatherproof wood adhesive because it grabs quickly and dries solid/clear but I've seen people try to assemble kits with school PVA, superglue or even hot glue (which never works). With this in mind I try to design kits that don't require glue at all, the useless machine went from a glue heavy box to a completely glue free box (and it only took 4 years apparently).

This new kit has one awkward part that must be glued and because it connects the drive shaft to the motor it needs to be glued properly. It's four layers of material and is the kind of part that should be manufactured a different way but time is not on my side. Instead of building each one individually I realised I could build several at once to speed things up. By leaving a row of them held together on a sprue I can glue a whole row at the same time, the sprue even helps with aligning the layers accurately. Once the glue has dried I can just snap off one at a time and insert them into the kits.

This allows me to ship another 'glue free' kit without driving myself mad with assembly, which is nice.

by (Martin Raynsford) at 26 August 2018 07:24 AM

25 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

New Kit available soon

Feels like a long time since I put together a new kit but I'm pleased to announce this little WiFi controlled strandbeest is going to be available at EMF camp this coming weekend and shortly after it'll be available online. It's a mash up of the plastic strandbeest kits and my recent ESP8266 experiments so it can be driven from any mobile device.

by (Martin Raynsford) at 25 August 2018 01:54 PM

23 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Something completely different

I had a spare day and an opportunity to go on a royal icing course so I thought it would be fun to try, plus another thing to learn about that compliments the rest of my cake stuff. I learnt loads of interesting things about types of icing sugar and technique for piping icing, the brush effect on the flower is particularly effective.

by (Martin Raynsford) at 23 August 2018 08:30 PM

20 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Wooden Bar Top

The bar itself for Vale also had to be portable to get it out into the middle of the quarry. This poses a bit of a challenge because it's a large item. The wooden crates I made are so sturdy that they could be sat on so they were an appropriate place to start. The top itself is just several pallet planks sanded and connected together with a few batons. The surface then bolts into the crates with 6mm screws and wingnuts to make it fast. The whole thing goes together quickly and it all still fits on the trolley. It's a little bit low but it's functional.
I've been asking for pictures of the bar in situ but it doesn't appear anyone got one which is a shame. The whole 'setting up a bar in the middle of a warzone' thing got a bit serious almost immediately after we arrived (we were hoping for a little bit of time before anyone noticed us). It was good fun though, would definitely do it again.

by (Martin Raynsford) at 20 August 2018 09:37 PM

18 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Bar Sign

I really wish I had more photos of this. I made a sign for a bar that we ran at Vale, we set up a bar right in the middle of the quarry (hence the crates for moving beer). All good pubs need a sign and ours was no exception. The lettering and outline were coloured using paints, the areas were masked before cutting to allow a neat paint job.

The picture itself was transferred to the wood from a colour printout. There are lots of online tutorial that suggest all sorts of glue to use. The gist is that you print out onto a sheet, cover the whole thing in glue and stick it ink side down onto the wood. Once it has dried, you then wet the paper and slowly rub it off of the ink. The trouble is there is a very fine balance between not rubbing enough paper off and rubbing the ink off. In this case the blemishes work well with the style.

by (Martin Raynsford) at 18 August 2018 08:33 AM

16 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Wooden Crates

I have a lot of green plastic crates but I wanted something a little more rustic for events. I re purposed some pallets I acquired from the local industrial estate and turned them into these simple boxes. I put some small feet on the bottom that allow them to stack inside each other and they don't immediately slip off the trolley when you move them around. Not laser cut but I do rather enjoy my new mitre saw and it makes chopping planks so much easier.


by (Martin Raynsford) at 16 August 2018 10:05 PM

14 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

New Vale Machine Panels

The culmination of knobs, dials, bubble rods and seals were these two new panels to go into the machine at vale.The first panel has all the input devices, when each lever is flipped or slider moved then all the LED's built into the board change colour, the rods change flash rates and the dials also move. Nothing specific just general interaction to indicate that something has changed. The second board is very much like my Stranger Things messaging systems. The board has 50 leds built into it and they have been shuffled to display letters at random (even I don't know which LED is which letter). You can connect to the board via wifi and use it to send messages back from the machine to the players. It was used last event but I wasn't there to see if it was successful, I hope it went ok.

by (Martin Raynsford) at 14 August 2018 06:22 PM

12 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Knobs, Dials and Switches

I made a collection of dial and switches for Vale at the start of the year. I've done similar things before but this time they're all functional. The plan was to put them all onto a board and allow people to actually interact with the infernal machine this year.

by (Martin Raynsford) at 12 August 2018 09:29 PM

11 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Bubble Rods

I've had these 15mm bubble rods from Kitronik for quite a long time, I thought they would look good when side lit. I used a single neopixel on each end of the rod and illuminated both ends with the same colour. The colours slowly fade on/off and at different frequencies. 22mm copper pipe fittings make perfect end caps and the the laser cut adaptors to go between the two.

by (Martin Raynsford) at 11 August 2018 07:31 PM

10 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Demonic Seals

These demonic seals were cut in ye olde MDF for that genuinely realistic appeal. The disks were painted with metallic acrylic before engraving so it was easy to wipe the dust off. These seals were going to be used as decoration on the vale machine (and were made way back in May)

by (Martin Raynsford) at 10 August 2018 06:47 PM

Wolf Coaster

Just a sample for a coaster, I masked the acrylic with vinyl transfer tape before engraving to ensure that I got a good clean cut. I didn't realise it was a coaster otherwise I would have rounded the edges and engraved it on the reverse so that the engraving was on the underside and less prone to damage during use.

by (Martin Raynsford) at 10 August 2018 09:39 AM

09 August 2018

Martin Raynsford hackergotchi for Martin Raynsford

Voting Chits

This chits were made for the LRP Game, Age of Aether. I believe the top disk is copper, silver or gold and the larger bottom disk is red, green or blue to denote different groups and weightings. I would normally paint a sheet before cutting but because the exact combinations required were unknown I left them all blank.

by (Martin Raynsford) at 09 August 2018 07:25 PM

13 July 2018

Martin Raynsford hackergotchi for Martin Raynsford

Node timer counters

In one aspect of Vale I'm making tech to keep the node system functional, from the player side of things I'm trying to find ways to hit as many nodes as possible and collect all the stuff. While you're waiting at a node it would be really useful to know how long it had been since the node last spawned. There is a 6 hour window for 3 spawns so it's going to be roughly every 2 hours. I thought it would be handy to drop these counters near the node so anyone can update the time then, if you arrive 10 minutes after the previous drop it's worth going on to the next node.

They're based on this wound counter design but two concentric rings allows me to set the hour and the minutes separately.

by (Martin Raynsford) at 13 July 2018 09:13 PM

09 July 2018

Martin Raynsford hackergotchi for Martin Raynsford

Kickstarter Fulfilment and best ever Birch Ply

I'm deep into fulfilment for my kickstarter puzzles. Roughly 600 puzzles to make in total and I'm turning over about 50 a day which is pretty good progress. Obviously it's leaving me a little bit of time to blog this month which is why I'm catching up on posts. 

The high quality BR grade plywood from Kitronik is really worth the extra money. 1 in 10 sheets has the tiniest of knots but because each ply is only 0.5mm thick it still cuts through cleanly. All the inner layers are equally high standard. If your working on a project that needs better materials this is the stuff to go for.

by (Martin Raynsford) at 09 July 2018 07:11 PM

07 July 2018

Martin Raynsford hackergotchi for Martin Raynsford

Truck Mudguards

The fathers day lorry is very similar to most of the cars we've already done but to really make it feel like a proper truck is needed some mud guards over the wheels. It would be hard to laser cut something directly to go over them but thanks to the vacuum former I can laser cut some moulds and make some plastic arches to go over them instead. Now the arches can be covered with sugar paste to match the rest of the cake.

by (Martin Raynsford) at 07 July 2018 07:58 PM

06 July 2018

Martin Raynsford hackergotchi for Martin Raynsford

Roman Horseman Shield

This item wasn't actually designed or drawn by me, I did help out though. Eli was tasked with designing a Roman shield based on his trip to the Lunt Roman Fort. He chose to make a horseman shield which is rounded to protect the horses legs. He drew the whole thing in inkscape, picked the colours and we took it to the laser. The wings were actually drawn 7 years ago so it was nice just to be able to drag the files out of my archives and use them again. The shield boss was made from vacuum formed plastic.

by (Martin Raynsford) at 06 July 2018 06:02 PM

05 July 2018

Martin Raynsford hackergotchi for Martin Raynsford

Confirmation Cake Topper

A quick laser cut from way back in May, this cake topper was to celebrate Daniels Confirmation (obviously). The spikes are a little bit fragile and spiky but it only has to go into the cake once right.

by (Martin Raynsford) at 05 July 2018 08:05 PM

19 June 2018

Martin Raynsford hackergotchi for Martin Raynsford

Fathers Day Cake Lorry

Way back in February, Dawn had the idea of making a cake based lorry in the same style as the Cake cars we're been doing. It was a great idea but I knew to shift all of the additional weight of a trailer we were going to need four driving wheels and motors. The majority of the weight would be spread over the rear of the trailer so those wheels and axles were put in place with bearings to reduce the rolling resistance. The pivot point was again made with a bearing to ease turning friction. Other minor changes included a reversing beeper and a second set of brake lights on the trailer itself (with curly cable between cab and trailer). The whole thing worked well for this quick demonstration.

The problems came when I loaded the trailer down with any weight. I ran my tests using 10kg of weight which the cab was able to pull but the steering was totally ineffective. All the weight was pushed into the drive wheels making the steering light, the sheer power of the four motors just ploughed the cab on in a straight line. At this point I was lucky with some previous design decisions. Using different motors for left and right wheels allowed me to implement a software differential between the wheels. By making the left turn faster than the right, the whole cab will steer right regardless of what the steering is doing. A little bit of tweaking got the two to line up so that the whole thing turns the right amount based on the user input.

This major problem with the lorry has been back propagated through the cars. It was only a minor issue on the cars but now it's completely gone and the cars drive much better because of it.

Dawn eventually turned the lorry into a Carlsberg van capable of dispensing beer (from a 5kg keg) hidden in the back and it's probably the best fathers day cake in the world.

by (Martin Raynsford) at 19 June 2018 07:16 PM

18 June 2018

Martin Raynsford hackergotchi for Martin Raynsford

The right tools for the job

My Kickstarter puzzles all need to be dyed and oiled before I can put the final assembly together. Obviously they can't be stacked up while they're drying so making a drying rack to store all the sheets without touching each other seemed to be a sensible idea. The whole thing was coated with some spray lacquer to stop the burnt edges of the rack marking the sheets. The whole thing works just as intended.

Another tool for the job was made without going anywhere near the laser and it's as simple as a stack of wood. A dozen planks of ply were cut to each hold a single puzzle and it's pieces. The front panel of the puzzle gets glued to the back panel and the whole thing is put on the bottom of the stack. The weight of the boards, stiffness of 12mm ply plus some extra weights from my screw boxes hold all the puzzles perfectly flat while the glue dries. When the puzzle comes out of the top of the stack it's ready for it's paper coating and it can then go in the pile of completed puzzles. Simple but effective.

by (Martin Raynsford) at 18 June 2018 08:46 PM