Planet Nottinghack

27 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Square Pumpkin

After the great boxplosion of twenty fourteen my cubic pumpkin got rather neglected. Halloween came and went and I was busy working on Fraggle rock so this week I decided to carve the pumpkin rather than let it go to rot with all the others. It's a lot squarer than the first one and it made carving the flat faces easier but I'll give it another shot next year and see if I can get the things I really want cut into one. 

by (Martin Raynsford) at 27 November 2014 10:22 PM

Chuck Type Burr Puzzle

This is a 24 Piece, Chuck Type, Burr Puzzle, made from 12mm Poplar plywood. The chuck type burrs have U shaped sticks of varying lengths and 1-2 locking sticks to keep the whole puzzle together. The locking pieces were made by creating a U shaped stick and then rotating it 90 degrees and removing the locking section. It's also possible to make a 6 piece burr but the larger puzzle is much more interesting to assemble, plus you can make the 6 piece with parts from the big one (svg here)


by (Martin Raynsford) at 27 November 2014 08:34 PM

New Page

I get a lot of questions about what machines I'm using so I've added a new page to the top bar so readers can see what my current set up is at any given moment.

by (Martin Raynsford) at 27 November 2014 01:06 AM

26 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Micro Crossbow

Inspired by the King of Randoms Micro crossbow on Instructables I decided to up the ante a little and laser cut a matching crossbow but this one has a trigger to launch the projectile. I'll be writing an instructable for it shortly but for now here is the file (svg here).

by (Martin Raynsford) at 26 November 2014 02:43 PM

25 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Winter Trio

Clearly I'm in a festive mood this evening because I've made 2 more characters to go with the snowman.(svg here)

They're now available in my shops too 

by (Martin Raynsford) at 25 November 2014 10:10 PM

12mm Snowman

12mm thick that is, using the 12mm ply allows the snowman to stand up without need for additional support. I'm off to work on the next stand up design.

by (Martin Raynsford) at 25 November 2014 07:54 PM

EMF Camp Light beacon

I made this light beacon for EMF camp (you can just about see it in this post). It sat on top of the laser and span round slowly shifting between 2 colours all weekend. People like Blinkenlights and I got a few compliments on it, especially as we left it running in the dark all night. Not bad for something slung together in a field. I never got round to posting it. I had a lot of fun with yesterdays alarm clock though so I thought I'd resurrect it and put a whole bunch of new patterns into it.

I didn't quite get as many done today as I hoped but I did have fun coding and I also got electrocuted by it (entirely my own fault). I have at least set up a framework for adding animations, so next EMF camp/Maker faire I can just add patterns as I think of them. Here is a short video of the 4 patterns it now cycles through. It's no LED cube but it's a start.

by (Martin Raynsford) at 25 November 2014 01:46 AM

24 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Stellated Dodecahedron II

This item is nearly 12 months overdue but I'm really pleased I actually got round to finishing it. It's another small stellated dodecahedron but it is much better known as Gravitation by M.C. Escher. 12 Turtles sit amongst the shape, the turtles are not fixed down instead relying on the framework to hold them in place. When rotated the turtles rattle around which makes a pleasing noise. Each turtle outline was cut from ply and painted before it was returned to the laser cutter to have the details added to it. 


by (Martin Raynsford) at 24 November 2014 03:56 PM

Childs Sunshine Alarm Clock

Eli sleeps with a little Gro Clock in his bedroom, for those that don't know it's an alarm clock the switches between a day and a night image so children who can't tell the time know when it's acceptable to get up in the morning. I would recommend them. Sadly I left ours at Grannies after the weekend and Eli wasn't keen to sleep without it. So I rummaged round the garage, found some parts I knew were out there and knocked together this arduino based version of the same clock. Being Arduino relied on the existing libraries to write the code quickly.

  • Power for the whole arrangement comes through the USB connection
    5V, GND from both the RTC and the Neopixel Ring are connected to the Arduino.
  • Data in from the Neopixel Ring connects to Digital input 2 on the Arduino
  • SCL of the RTC goes to Analogue input 5 on the Arduino
  • SDA of the RTC goes to Analogue input 4 on the Arduino
Full source is available for download from here 
  • The first lines of the setup function define the time that the alarm will go off
  • The RTC and Neopixel ring are initialised
  • Two alarms are created, one at the time previously specified another an hour later
  • The main loop of the program does nothing except create a delay that keeps the timer ticking
  • LightsOn function, creates the short sunshine animation when the alarm goes off
  • LightsOff function, switches the LED's back to night time colour

by (Martin Raynsford) at 24 November 2014 12:44 AM

23 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Koch snowflakes

I'm heading to a local craft faire at the start of December and I wanted to make something Christmassy and pocket money priced. Given that the previous tessellations have gone down well I thought these Koch Snowflakes tick all the boxes will still being geeky and Mathemagical. I'll let you know if they sell well :) 

After several requests these snowflakes are now up for sale in my webstores

by (Martin Raynsford) at 23 November 2014 12:00 PM

22 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Laser Install

I've had my Whitetooth laser cutter for about 6 weeks now, it was pretty much dumped in the middle of the garage, wired up and left to run. The extraction used 150mm pipe and the hole in the wall was 100mm so I've been opening the garage door whenever I wanted to laser cut.  This week I finally got round to connecting it in properly and sorted out the tangled mess of wires. I still need to connect in the Blacknose to the extraction system and I'm waiting on a T piece to do that but it's starting to look pretty good out there. Oh and I do need to find a better way to keep the laptops on their precarious perches.

by (Martin Raynsford) at 22 November 2014 11:21 PM

Small Stellated Dodecahedron

As the title says, it's a small stellated dodecahedron. 12 identical panels interweave to form this dodecahedron shape. The ends clip together and hold in place although my stuff gets handled quite a bit so I put some glue in there too. It's very much an assembly puzzle but not as complicated as the Frabjous. (svg here)

This was made from 1.5mm external ply which is nasty to cut and is proper black all the way round the edge. Thankfully I think I've worn most of the charcoal off with the assembly. I keep meaning to rant about how poor quality the 1.5mm ply is because everyone passes off external ply as laserable, but I think there may be a new supplier in town shortly with some better quality stuff so I'll wait for that to happen and then shout their praise from the rooftops (again)

by (Martin Raynsford) at 22 November 2014 07:33 PM

20 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Enclosures with easy/reuseable access

Matt Brailsford asked if it was possible to make a laser cut enclosure with easy access for a battery compartment. My brain did it's annoying thing and designed 2 different mechanisms and wouldn't let me stop thinking about it until they were actually made. I made these two test pieces and I'm sharing the concept now because I'm sure other people will find them useful. Both boxes use recessed bolts so they sit completely flat on the work surface and they also use captive nuts to screw the lids down. (svg here)

Flap Access
This is my preferred design, a single screw secures the access panel in place. Two hinges stop the lid from coming out at the other end. The captive nut is rounded off because it sticks slightly out into the access area. A lip all the way round the edge stops the lid from falling into the box. The downside is that this lip uses quite a lot of material.

Base Access
Four captive nuts, one in each corner, allow the entire base to be removed. The corner blocks make the box sturdy but it can be pretty time consuming to remove all four screws.

by (Martin Raynsford) at 20 November 2014 12:19 AM

19 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Musical Sugru Ear Defenders

With 2 lasers now running in my garage the pumps and fans can really drone on (I'm yet to box them in to make them quieter). I've been wearing my ear defenders quite a bit recently to help keep me sane (and to keep my ears warm) but I also like listening to music while I work and the two are not very compatible. I headed off to the interwebs to see if headphone ear defenders were a thing and it turns out they are. £33 will get you a set of defenders with an audio jack input, being a bit of a cheapskate I suddenly realised that I could add headphones to my £3 ear defenders, have them ready asap and have spent significantly less amounts of money on them.

The process was pretty simple. Drill some holes in the side of the defenders large enough to pass in some ear buds and then hold them in place with some sugru. Job done, everyone has a pair of ear buds kicking around and I picked up the sugru at one of the many maker faires I've been to, so not only did I have a set by the end of the evening I also didn't have to pay anything extra for them.

by (Martin Raynsford) at 19 November 2014 11:02 PM

17 November 2014

Kate Bolin hackergotchi for Kate Bolin

Me when sewing.

Me when sewing.

17 November 2014 04:00 PM

11 November 2014

Matt Little

Enginnering in Development 'Energy' Book

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Over the past two years a number of people have been working on a series of books for Engineers Without Borders placement volunteers.

These books are designed to cover the basics of the theoretical, practical and social aspects of doing engineering projects for devlopment. They are meant as a basic guide, a collection of case studies and links to further information.

I have helped co-athour the Energy book and it has been published and released as a free .pdf.

I'm very proud of the final result which, I think, is an amazing resource.


by (Matthew Little) at 11 November 2014 02:53 PM

Wind Empowerment Conference 2014

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For the past week I have been at the 2nd Wind Empowerment conference in Athens.

Wind Empowerment is a network of groups working on Small Wind Turbines, with a particular focus on the Hugh Piggott designed wind turbine.

The conference was an inspiring mix of interesting presentations, hands-on workshops and social fun. Around 45 people from at least 10 countries attended.

Here are some notes and photos from the event.


by (Matthew Little) at 11 November 2014 10:11 AM

Kate Bolin hackergotchi for Kate Bolin

notanicedragon: The double knitting technique is great. It has...


The double knitting technique is great. It has a light side, and a dark side, it binds the scarf together… you can see where I’m going with this can’t you. I only found out about double knitting this past summer and got monumentally carried away. This Star Wars Scarf is just one of the results.

Click on the knitting charts for full sized images. They are worked in order bottom to top.

11 November 2014 09:16 AM

09 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

12mm ply wood

I now have a whitetooth laser cutter stashed in my garage, with it's 80W laser tube I know it was capable of cutting 12mm laser ply at a decent speed (18mm/s) but I hadn't actually got round to making anything out of it. I decided to break into my pile of 12mm ply by making a very very large version of my marble machine. 40mm wooden balls now roll around a quadruple sized version of MM1. 

by (Martin Raynsford) at 09 November 2014 10:39 PM

Kate Bolin hackergotchi for Kate Bolin

Life at the Hackspace.

Life at the Hackspace.

09 November 2014 11:07 AM

Martin Raynsford hackergotchi for Martin Raynsford

Carcassonne game release

I tried to run a kickstarter style campaign to build up to the release of my Carcassonne files. For numerous reasons we never actually reached the £500 I was hoping to get, but I have decided to release the files anyway to the people that participated.

I will continue on with my running total and once I reach the required amount I will release the files into the wild, but for the mean time you can still purchase them for a small £10 payment.

£200/£500 raised

Purchase the Carcassonne files from here.

by (Martin Raynsford) at 09 November 2014 09:20 AM

07 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Fraggle Rock in Cake

A fairly hefty picture post from me tonight. I've been involved in a very large project for the last 6 weeks. I've had a few teaser posts about it already but yesterday was the big set up day. Dinkydoodle Designs wanted to build a massive exhibition cake to show at Cake International 2014 but always wanting to wow the visitors Dawn decided to make the cakes move which is where I got drafted in. I designed, built, wired and programmed all the internals and these wonderful cake creations were built upon my bases. The show will run for 3 days and will finish on Sunday if you want to head over and see these things for yourself.

I'm going to run a short series of blog posts showing all the mechanisms as they got up to this point and explaining how each one was put together but at its heart most of these system boil down down to an arduino and a 15kg torque servo.



by (Martin Raynsford) at 07 November 2014 11:39 PM

03 November 2014

Dominic Morrow hackergotchi for Dominic Morrow

so you want to run a maker faire?

In the last weekend of October I co-produced the 3rd Derby Mini Maker Faire at the SIlk Mill museum in Continue reading

by chickengrylls at 03 November 2014 12:55 PM

02 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

Church window

I was inspired by this instructable by pohhoushun to have a go at making my own church window. You can really get into it once you start adding all the little details over everything. I've ended up with an amazing little window and I'm inspired to make more, what a super idea.

by (Martin Raynsford) at 02 November 2014 04:42 PM

Matt Little

Renewable Energy Resource Monitor

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Following on from the work done for the Wind Datalogger and the Latrine Logger, we are bringing these ideas together to create a Renewable Energy Resource Monitor.

This is a Arduino-based data-logger which has a range of sensors which can measure different weather resources which relate to renewable energy generators. The end result is low-cost and open-source for accessibility for all.

This post explains the problem and will contain information on the prototype as it develops.

This project will be open-source and PCB design, software and hardware designs are available on GITHUB.


by (Matthew Little) at 02 November 2014 03:50 PM

01 November 2014

Martin Raynsford hackergotchi for Martin Raynsford

T Rex Cake toppers

A custom request that I managed to squeeze in this afternoon (sorry it's slow round here but there is a massive project under way). The request was that the cake topper has spikes that would hold it up in the cake but could be removed to make it a nice item after the birthday. I've managed to get both at once by using a spikey font :)

by (Martin Raynsford) at 01 November 2014 02:35 PM

31 October 2014

Matt Little

Arduino and Mobile Data

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I've been wanting to play around with sending data via a mobile SIM card and, after needing to do it for anothe project, here is a short post on my attempts at getting it all going.

I used an off the shelf GSM/GPRS module (the SIM900).

I tried this using both the Arduino Uno and the Arduino Leonardo.

Here are the results from my tests.


by (Matthew Little) at 31 October 2014 08:30 PM

30 October 2014

Iain Sharp

Sholto builds a cool LushOne case

Sholto's LushOne Case

Sholto’s LushOne case

Another excellent case for the LushOne described by Sholto on Instructables. The project work that people do on top of the basic LushOne kits continues to be a delight!

by Iain at 30 October 2014 01:29 PM

28 October 2014

Matt Little

DataDuino - Arduino data acquisition unit

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The DataDuino data acquisition (DAQ) kit is designed to be robust and configurable but relatively simple. It is based upon the Arduino platform (using the Uno bootloader). It stores data to an SD card and uses a real time clock for accurate timestamping. The fastest resolution is 1 second sampling, up to 99999 second sampling.

Data acquisition is always useful to monitor a wide range of projects. Knowledge is power. With data, you can monitor your system, make changes and record how well they do and generally improve the things you are working on. Also having real data and real facts is vital if we are trying to prove an effect.

Data is stored onto an SD card. A real time clock is used to time-stamp the data and the output is a .csv file.

Sample Arduino code for a datalogger unit is provided here and can be built upon.

This kit is available as a kit for £25 (including UK p&p).


by (Matthew Little) at 28 October 2014 05:18 PM

Bat Detector


Welcome to fascinating world of bats! This bat detector device converts ultrasonic sounds created by bats and convert them down to a lower frequency so that we humans can hear them.

Bats use ultra-sonic pulses to navigate and to detect prey. These pulses are very high pitch (around 5 times the maximum frequency humans can hear). This electronic circuit converts the high pitched sounds produced by bats to a human-audible level. It can also be used to listen to other high frequencies such as peeling sticky tape, compact fluorescent lights and power supplies. 

 This kit costs £20 for professional circuit board and all electronic components. This includes free P&P within the UK.


by (Matthew Little) at 28 October 2014 05:17 PM

23 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Board Gamingible

I wrote an instructable last night which rounds up a lot of my board gaming type posts.

It was also supposed to inspire people to support my jumpstart campaign for Carcassonne files so consider this a gentle nudge for my blog readers too

by (Martin Raynsford) at 23 October 2014 08:22 AM

20 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Laser Cutter Comparisons

I'm often asked to offer comparison between laser cutters 'X' and 'Y'. I feel it's important to try and offer impartial advice, we do have our own laser importing business after all so it would be very easy to be biased. The trouble is that I'm not sure what people are really asking when they want two machines compared so I thought I'd write a little blog post to talk about the basic comparison and discuss the most important thing that people always overlook.

Laser cutters are often presented alongside a pretty dull technical spec sheet. This is straight forward list of details about laser power, cutting area and cutting speeds, sometimes it also includes price. I would hope that most people are able to do these comparisons for themselves. Bigger cutting area is better, more laser power is better and often comes at an increased price. 

This is where the question confuses me. The only information I have about the other laser cutter is this dull spreadsheet which is easy to compare and laser cutters are all very similar mechanically. Big metal box to avoid blinding, check. Laser beams to cut through material, check. Extractor fan to keep air breathable, check. In fact it's the most significant item and the most important detail that is often glossed over on the list or ignored completely. I'm unable to comment/compare the Laser cutter controller if the listing doesn't even tell me what controller it is.

The control software is such a significant part of the whole laser cutter experience I'm completely amazed that some listings don't even mention what the controller is. 90% of the time the laser cutter is a black box on the end of a usb cable, you deal with the software interface to prepare the files you are working on. You need software that is functional and straight forward at the very least. I've seen a laser cutter that had Chinese software called 'Printer Driver', that was all we knew about it and it's impossible to Google that for any more information.

If I were buying another laser cutter I would insist upon knowing what controller it came with in advance. If I can't find any useful resources about that software online I would not purchase the laser, it's a simple as that. Life is too short to faff with badly written software, some of these laser cutter controllers are even described as completely unusable by reviewers. I would even go one step further, if a supplier is unable to provide me with a demo version of the control software it would worry me. Are they trying to hide their bad software or do they just not know how to set up the demo? Either case is pretty bad, and this applies to all manufacturers, cheap eBay lasers and UK importers.

These are standards that I hold our own company to. All of our laser cutters use Lasercut 5.3.
I won't lie and tell you it is the greatest software ever written; it is the perfectly acceptable face of cheap laser cutter controllers. We offer a download and demo version of the software so you can check it out before you even get near one of our machines. The community is also pulling together to create some really useful resources for it and are slowly dissecting some of the more complex parts of the system.

by (Martin Raynsford) at 20 October 2014 11:33 PM

17 October 2014

Martin Raynsford hackergotchi for Martin Raynsford


Image tolen from the interwebz because I forgot this blog post was scheduled but not completed
3 years ago today I posted my very first Laser Cut Item, a simple card for Kim. I had bought the laser cutter a few weeks earlier and I had decided to embark upon a crazy project to laser cut 365 things in 365 days. Now 3 years on, I've complete the 365 things, the 52 things, made a job from my hobby and started a laser import company that is really taking off.

Who knows what I'll be doing this time next year but I can tell you, I'm working on some big projects at the moment. I should be displaying more of the parts for you and I can't wait for this first one to be finished because there will be some awesome pictures. I'm also working on open source controllers for laser cutters and some other nifty little tricks you can do with our lasers so it looks like it's going to be another fun year.

by (Martin Raynsford) at 17 October 2014 04:00 PM

16 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Animitronic Mannequin

Another quick turn around part for this upcoming cake project. You'll have to trust me that there are laser cut parts in there. I used an arduino to drive the 3 servos; head, tail and foot. Power comes from a small 5V brick and it's connected directly to the mains. Believe it or not this will get covered in icing and become a 'cake', for now it's been sent off to the wizards so they can work their magic.

by (Martin Raynsford) at 16 October 2014 10:18 PM

15 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Massive Cake Stand

This massive cake stand (1200 long) is a small part of the new project I'm working on. I can't give too many details yet but I just built 20 of these sections all of which will be stacked with cake in the near future. Stay tuned because this project is awesome and huge.

by (Martin Raynsford) at 15 October 2014 09:53 PM

14 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Getting Jiggy with it

It's not just about the things you can make with a laser cutter, the laser can also help you make things to make other things. I've been making these internet boxes for quite some time now, each one has a hole in the top and two holes in the side. I've been drilling them by eye for far too long so I finally got round to building a jig to hold the boxes in the right place for me. The vertical slot lines it up to drill a hole in the top. The horizontal slot is larger than the side of the box, pushing it to the top lines up one hole, pulling it down to the bottom allows the second hole to be placed just above it.

by (Martin Raynsford) at 14 October 2014 09:51 PM

11 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Chaosdorf Bottle Tops

Last night at Chaosdorf we cut a few little samples to see what would work on the laser cutter. This bottle top was a fantastic success. I'm expecting some awesome things when they start engraving their own logos on to the bottle tops for their home brew (and now I'm home again I'm relaxing and thoroughly enjoying one of the bottles we bought home with us)

by (Martin Raynsford) at 11 October 2014 08:54 PM

10 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Chaosdorf Cutting

Tonight I'm in Germany and more specifically Düsseldorf where we're visiting the Chaosdorf Hackspace. We have just installed a Greyfin laser cutter and they decided to engrave the hackspace logo onto the top of an old IBM thinkpad. They've picked up the software pretty quickly, imported their design and with a few gentle nudges have etched this logo onto the lid of the laptop. After a bit of a cleaning scrub it came out really nicely. 

It'll be a fun night here at their social evening and then back to the UK for Dominic and I tomorrow.

by (Martin Raynsford) at 10 October 2014 04:27 PM

09 October 2014

Spencer Owen hackergotchi for Spencer Owen

RC2014 SD Bootloader Update

Just a quick update to about the SD Bootloader I designed a few posts ago.  Well, the PCBs have arrived and last week I took a soldering iron to one of them and gave it a quick test

One side of the board is effectively an Arduino, so without plugging it in to the RC2014, I connected up an FTDI lead and uploaded the Arduino Blink sketch.  A quick check with a multimeter and one of the pins was altenating between 5v and 0v.  So far, all good!

Next, I uploaded a simple sketch that would count on from 0 to 255 in binary on the 8 output pin and plugged it in to the RC2014

int data_0 = 14;
int data_1 = 15;
int data_2 = 16;
int data_3 = 17;
int data_4 = 18;
int data_5 = 19;
int data_6 = 2;
int data_7 = 3;
int inbyte = 55;

void setup()
  pinMode (data_0, OUTPUT);
  pinMode (data_1, OUTPUT);
  pinMode (data_2, OUTPUT);
  pinMode (data_3, OUTPUT);
  pinMode (data_4, OUTPUT);
  pinMode (data_5, OUTPUT);
  pinMode (data_6, OUTPUT);
  pinMode (data_7, OUTPUT);  

void loop()
  for (int inbyte = 1; inbyte < 255; inbyte++){
    digitalWrite(data_0, inbyte & 0x01);
    digitalWrite(data_1, inbyte & 0x02);
    digitalWrite(data_2, inbyte & 0x04);
    digitalWrite(data_3, inbyte & 0x08);
    digitalWrite(data_4, inbyte & 0x10);
    digitalWrite(data_5, inbyte & 0x20);
    digitalWrite(data_6, inbyte & 0x40);
    digitalWrite(data_7, inbyte & 0x80);

    delay (1000);

A simple BASIC program on the RC2012 displayed the numbers it was reading.


It looked like success at first, but then I realised it was counting up in a very haphazard way.  After jotting down a few of the numbers in order and converting them to binary it became obvious that I’d wired up the analog pins A5 – A0 not A0 to A5.  A quick change of the Arduino code and all was good there!


The Bootloader board has 6 output lines from the Z80, 3 of which go to the Atmel ‘328 and 3 go to LEDs.  A BASIC test using OUT 0,1 OUT 0,2 and OUT 0,4 showed that the LED outputs worked, so I figured the other 3 would do too.  So, next to get the SD card reading.

This proved to be harder than expected! I had designed the SD header on the end of the PCB so that it could be wired up in a few different ways.  One of these was through a “poor mans SD adapter” (Simply a micro SD adapter with 0.1″ header pins soldered on!).  This didn’t work, but maybe it was my soldering – I did melt the adapter a little bit!  I had some cheapo chinese SD boards from eBay, so I gave on of those a go, but still nothing.  Tried the other one.  Nope.

I assumed that there was a problem with the new board, but to rule things out, I tried a genuine Arduino with one of the SD boards.  Still nothing.  Another Arduino… That didn’t work either.  Maybe different SD card?  No difference.


Conclusion is that all the SD adapters are dead!  In the mean time, however, I did discover that using a resistor voltage divider to get the 3v3 needed for the SD card won’t work and that a proper 3v3 regulator is needed.  The eBay boards have this so should have operated fine on 5v.

Then I remembered I had a faulty TFT screen with built in SD adapter.  As far as I know, it’s only the screen that’s faulty, but, hey, it’s worth a try, right!  And, would you believe it, it worked!  About 3 hours had been wasted on faulty hardware – which wasn’t even anything I had built or designed!


So, inspired by this, I worked on getting data from an SD card on to the RC2014.  There are two sides to this; The RC2014 sets an output high, waits a moment and reads an input, sets the output low and reads the next input and so on.  The ‘328 reads a byte of a file on an SD card, puts it on the output pins, waits for the input to change and reads the next byte and so on…


The result is that in BASIC at least, the RC2014 can read from an SD card!

The next stage is to write this in Z80 assembly language and burn it to ROM so that it can read the SD card directly in to memory and start executing the code.

In the mean time, however, I have designed my own Micro SD Card adapter for this which has a built in voltage regulator. This should make things a lot neater!

by Spencer at 09 October 2014 08:59 PM

08 October 2014

Matt Little

The Prediction Machine

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The Prediction Machine is an interactive artwork which aims to engage the public with climate change issues via a fortune telling machine.

Created by the artist Rachel Jacobs in collaboration with myself, Ian Jones (Sherwood Wood), Matthew Gates, Robin Shackford, Juliet Robson, Dr Candice Howarth and Dr Carlo Buontempo.

I designed, built and tested the human-power device and electronic and electrical systems.

Here are some photos of the unit in action and the build details.


by (Matthew Little) at 08 October 2014 10:00 AM

Martin Raynsford hackergotchi for Martin Raynsford

More White Knight

My black on white, laser engraving laminate finally arrived so I could sit down and do some more of the White Knight Designs. As a game of thrones fan these two really caught my eye and it was good fun putting them through the laser cutter last night. Jordan has been great about sending me higher resolution artwork than I can steal from Facebook so I cut them in duplicate and will be sending the second set in his direction.

In the meantime don't forget about my attempt to jump start my Carcassonne set file release.

by (Martin Raynsford) at 08 October 2014 08:02 AM

07 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Jumpstart me Carcassonne

Nearly a year ago I completed my Laser cut set of Carcasonne, it's been up for sale in my webstore but I am continually asked to release the svg file so people can cut there own. I normally share all my files but I have a few problems with this one, it took 160 hours to draw the base tile set and a further 24 hours to draw the river. I haven't been able to justify giving the file away but with the world being the way it is I can't sell it as a file to individuals because it only takes one person to share the file elsewhere and I've lost all control over it. So I've come up with this 'Jumpstart me' idea.

I'm asking for just £500 (not a lot of 200 hours of work) and when I reach that amount I will release the files to all the people who have contributed towards the total, including the tile backs. 3 months later I will release the files publicly on my blog without tile backs. I will keep this page updated with the running total so you can see how close we are to reaching that total. I have set up a paypal link so you can purchase the files as many times as you like  (I'll try to figure out an easier way to send more money), but also because that gives you protection and the right to a refund at any point (although please just ask me because I'll happily return the money without paypal intervention). Let's see if this can work

Purchase the Carcassonne Files here

Current total £190 / £500

The small print
  • This is not a good way to recreate your own Carcassonne tiles. This is a deluxe version of the set and will cost far more than buying the basic set. 
  • If we do not reach the full amount by the 7th Novemeber, I will make the decision to cancel and refund everybody or accept the amount reached and release the files anyway.
  • The tiles are done with 3 cut operations, an etch, a low power cut and a high power cut. The low power cut can be very tricky to get right without cutting through the wood.
  • The files will come as svg, pdf and dxf. There were made in inkscape so svg is the native file type. pdf actually works as a universal file, the dxf imports into Lasercut 5.3
  • Lasercut 5.3 files can be supplied upon request.
  • This is not a full game it is a board game accessory, you should still buy an original copy to ensure you have the complete game.
  • Klaus-Jürgen Wrede, Z-Man Games or any other publisher please don't sue me for using your artwork, we just love your game and want to make our own awesome versions of it.

by (Martin Raynsford) at 07 October 2014 02:08 PM

06 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Foam Sword Blanks

This is not the project it should have been. I was supposed to be engraving this design onto the side of a blank sword (A 3 layer foam sandwich with a carbon fibre rod in the middle). I was supposed to mark the outline ready for cutting. The problem is that with the rod sticking out the end of the foam there was just no way to make the sword fit inside the 1200mm wide hole to get it under the laser head. It was really the wrong combination of thickness and size.

Plan B, I cut and engrave the swords as 3 separate panels and they get turned back into a sword when they are returned back to Eldritch. This was an option, right up until the moment I left Nottingham because even just foam blanks were 1100mm long.

Plan C, I cut the each layer in 2 parts, small enough so they fit inside my laser. 

As you can see, not everything works out as planned, This has left us with an interesting sandwich arrangement but I'm sure Simon will be able to work his magic in it. I shall post an update photo when the sword is completed.

by (Martin Raynsford) at 06 October 2014 03:41 PM

05 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Foam Sword Templates

I hadn't really thought about to before but when you're making a dozen similar LRP weapons at once it pays to have a template to trace around. Simon asked me to upgrade his lino templates to perspex ones which. There are 4 sizes, the longest being 1.1m long so I took a trip up to Nottingham hackspace to use their larger laser cutter. These were cut from 6mm perpsex and came out rather sturdy 

by (Martin Raynsford) at 05 October 2014 03:15 PM

04 October 2014

Martin Raynsford hackergotchi for Martin Raynsford

Wood Veneers

If you'll indulge me for a quick moment I'd like to follow up from the last materials post with a quick message about the joy of wood veneers. They're cheap, versatile, effective and with a bit of imagination you can put them to great effect. I've used them on some of my best projects. You can buy small single sheets of veneer for marquetry style pieces, they're typically 0.7mm thick.

What makes them great is that they'll fit in any size laser cutter, and even the cheap 40W Chinese imports can cut through them at a sensible speed. This makes the whole technique accessible to anyone with any laser cutter. I just restocked this week and picked up these 60 sheets of wood for 30 sheets (30 Great Britain Pounds for anyone not in the know).

So go buy some, you won't regret it. Also don't forget to pick up some magnets because the veneers often take on a slight warp and you'll need them to hold the work flat

by (Martin Raynsford) at 04 October 2014 02:54 PM

27 September 2014

Martin Raynsford hackergotchi for Martin Raynsford

New Materials Page

It's a bit of a work in progress but I've started to list the places that I buy my materials from. I get asked a lot about the poplar wood ply and I guess a blog post is only relevant for a week before it disappears off the bottom of the page (much like this will). So you'll note the new materials page in the header which will take you to the ever changing/growing list of materials I'm working with.

I'm actually still looking for laserable bamboo if anyone knows where to get some

by (Martin Raynsford) at 27 September 2014 04:16 PM

26 September 2014

Martin Raynsford hackergotchi for Martin Raynsford

White Knight Design

Every so often (OK quite often) I do things 'just because'. I saw Jordan's Facebook page for White Knight Design pop up on my feed the other day and I thought this material would work well for it.

What I really like about this project is the complete overkill. I started with a silver sheet and etched all the background away, leaving the logo proud. I love the matt surface left behind by a high resolution etch. It took an hour to etch 288x114mm so it's completely impractical and for that I love it.

by (Martin Raynsford) at 26 September 2014 10:39 PM

Pen and ink owl

Ed Saperia (of Heredox fame) introduced me to the wonderful pen and ink artwork of Iain Macarthur with the best of all questions, "can it be laser cut?". Move forward 6 weeks and while I was exhibiting at the rather quiet Leicester Creator Faire I finally found the 2.5 hours I needed to devote my laser cutter to engraving one of his pieces in sufficient resolution. I love the way the wood grain shows through on the etched patches giving it some extra depth amongst the intricate details. Sadly I fear that the stark black and white of the original does this piece far more justice than the cream and burnt colours of the laser but it was a fun piece to etch and the visitors enjoyed seeing the laser do all of the hard work..

by (Martin Raynsford) at 26 September 2014 07:46 PM

24 September 2014

Martin Raynsford hackergotchi for Martin Raynsford

Rocket and Groot

I loved guardians of the galaxy and I was inspired to make this veneer portrait of Rocket and Groot. I used layered veneers on Groot to make the different sections of his body stand out. If I were to remake it I think I would add a little more definition to Rockets gun to make it seem a bit more 3D (svg here)

by (Martin Raynsford) at 24 September 2014 10:58 PM

Quartz Fail

I'm always happy to try new materials that people send me to see if they can be engraved and this time it was the turn of Quartz crystals. Slate, Sandstone and Marble all engrave so there was always a chance this could work and as you can see from the image it wasn't a complete failure but the quartz was chipping away under the laser beams so it makes for some very rough edges to the engrave. It's not good enough to warrant doing again but at least it has been tried now.

by (Martin Raynsford) at 24 September 2014 09:52 AM

23 September 2014

Matt Little


No image

Its very difficult to explain the concepts of power and energy. People often ask me "Can I power my kettle with that?".

So to try and put the energy in a cup of tea into perspective I built the 'Cuppa-meter'.

The 'Cuppa-meter' shows a cup of tea which lights up as the energy required for a cup of tea is generated. This can be plugged into a pedal generator and people can 'feel' the energy required to make a cup of tea.

They can either pedal slowly (and hence low power) for a long time, or they can pedal hard (high power) for a shorter time. The end result (the energy) is the same - a nice hot cup of tea (or rather a lit up image of one).

 This post gives a few images of the cup of tea and also the calculations used.


by (Matthew Little) at 23 September 2014 02:22 PM

22 September 2014

Mouse hackergotchi for Mouse

I love Crow T Robot

Crow is the best

by Mouse at 22 September 2014 11:55 PM

21 September 2014

Martin Raynsford hackergotchi for Martin Raynsford

Bring forth the Galleries

Over the next few days I'll be making some changes to the blog and adding some content to the bar at the top. I'm starting with the galleries. Underneath the blog I've been storing all my images in several picasa photo albums (they tie in nicely with the blogger interface). Now that the blog has grown to 700+ posts it's hard to randomly browse it all to see all of the things. This way you can browse the galleries directly and more easily find your way to the good stuff. Happy browsing.

Oh and btw, having just browsed all the galleries myself, this Iron Man wood veneer is my current most favourite item of all time (subject to change of course)

by (Martin Raynsford) at 21 September 2014 09:48 PM

Teacups Follow Up

This is the cake that dinkydoodle designs made, on top of the cake stand that I made. In a rather disappointing twist the stand worked perfectly during testing but failed when it was fully loaded up with cake. The customer was unaware of the rotating potential so nothing really hurt except a bit of pride. More photos of this wonderful cakey creation can be found on their FB page.

by (Martin Raynsford) at 21 September 2014 08:31 PM

20 September 2014

Kate Bolin hackergotchi for Kate Bolin

Kara Stone and Gabby DaRienzo made Knitting Simulator, a game...

Kara Stone and Gabby DaRienzo made Knitting Simulator, a game that uses a Makey Makey, a tilt switch and some knitting needles to knit your way to awesomeness.

I just wish it wasn’t just for Mac, because OMFG let me virtually knit!

20 September 2014 08:56 PM

16 September 2014

Spencer Owen hackergotchi for Spencer Owen

Chromecast to VGA


When Google first launched the Chromecast, I wanted one as it seemed like it would solve a lot of viewing problems for me.  The trouble was, my “TV” (technically, it’s a 42″ monitor as it has no tuner) doesn’t have any HDMI sockets, so it would cause more issues than it would solve, and I figured it would be £30 wasted.


When the price was dropped to £18 recently though, I figured that was within the realms of wasteable money I was prepared to spend.  My TV didn’t have HDMI, but it did have composite, RGB, SCART and VGA connections.  Surely something would work…

I remembered that I had got hold of a HDMI to VGA adapter for the Raspberry Pi which worked quite well (both times I tried it!), and although I couldn’t find any definitive answers on line, I thought I’d give it a go.


These are plentiful on eBay for under £5, although there are several variations, and I can only vouch for the ones that look the same as the ones shown above.  eBay listings update more often than this blog post will, so I won’t link to a specific one, but search for “HDMI VGA Raspberry” and you should find some that looks like the photo above.  Some of them do not have audio out though, so watch out for those as they’ll be a problem.

The first problem I found, however, was that the Chromecast had a male HDMI plug.  So did the VGA adapter.  I had my doubts, but a female to female HDMI adapter (£2 from eBay) worked a treat!  Add in a 3.5mm jack to twin phono adapter (your audio set up might be ok with the 3.5mm lead that comes with the adapter – alternatively, you might need to buy an amp and speakers!) and I was good to go


It might look a bit gangly, but the point is, it works!  Google Chromecast to VGA TV for under £27! (And most of the ganglyness is hidden in normal use anyway)


Generally, this works perfectly streaming 720P to my TV.  The only slight niggles I have is that I lose about an inch of picture down the left hand side (but not really noticable), and when the power is removed from the Chromecast the speakers make a funny popping sound (probably the caps in the VGA discharging).  But otherwise, all is good.

So, if you want a Chromecast but don’t think you can use it, think again. 

by Spencer at 16 September 2014 05:11 PM

15 September 2014

Spencer Owen hackergotchi for Spencer Owen

RC2014 Bootloader for SD Cards

So, the RC2014 is great.  I can run Microsoft BASIC and program it from there, and as long as I am using a terminal emulator, I can copy & paste to save and load programs.  Alternatively, I can write Z80 code using an online compiler then download it, copy it to USB stick, move it to my old Windows 2000 laptop (which has a parallel port) so I can burn it on to EPROM to see if it works, make adjustments and repeat with another EPROM.

I will be the first to admit, however, that this is probably not the most efficient workflow.  Not to mention the time and effort involved in wiping the limited stock of aged EPROMS.

So, I am in the process of designing an SD Card based bootloader.

i (2)

Interfacing a Z80 to an SD card isn’t totally straightforward though.  For starters, the Z80 runs on an 8 bit parallel data bus, but SD cards use a Serial Peripheral Interface (SPI).  The Z80 is 5v, the SD card us 3v3.  And as for using the Z80 to address a particular memory location on the card… well, forget it!

[Sometimes I seriously wonder just how Zilog expected their Z80 to address things like 512GB of SD card when they designed it back in 1975!]

So I’ve decided to use a modern ‘cludge’ to provide the glue to stick the two parts together..  An Atmel ATMEGA328 (Arduino) speaks SPI and has enough pins to provide an 8 bit signal.  I will use the same interfacing technique as I used with the LED Matrix displays so that there’s a buffer between the Z80 and ‘328

IMG_20140911_210721 (2)

I hooked up a rough and ready breadboard & Arduino test to prove the concept, but initially I had lots of Odd Things™ happening, and all but came to giving up.


At the last moment, I spotted the school boy error.  The power rails of my breadboards are divided in to two halves, and despite having things connected to both sides I didn’t have anything to connect the two.  So the decoder chip was being back-fed through the SD card adapter.  Ooops!  In my defence though, it really is bloody stupid for breadboard manufacturers to not join up the power rails all the way through.  It is bad enough that the two sides aren’t linked – although I can appreciate you might want maybe a 5v and a 3v3 volt rail… but splitting it down each side too, well, this has now become a more of a rant than a blog.

Screenshot from 2014-09-14 22:15:22

So, with the Arduino able to put characters on the Z80 data bus that I could read with BASIC, I decided it was time to take it to PCB level.  I’ve got 8 bytes of data input from the ‘328 to the Z80 via a 74HC245 and 3 bits of output from the Z80 to the ‘328 via a 74LS374 selected from a 74LS138.  (There is also 3 output lines going to LEDs for status monitoring).  The hardware should be easy enough, so I’ve laid out the PCB and sent it off to OSHPark to be manufactured.  It is, however, the largest and most complex board on the RC2014 so far.

The software will be the tricky bit for me.  Firstly, I need to write a boot loader in assembly language and burn it to an EPROM (wasn’t this what I was trying to avoid???).  Secondly, I need to write an Arduino sketch that will read an SD card and write it out to the 8 bit parallel bus.  From a timing perspective, I have assumed that the Z80 will write to it’s output so the ‘328 will know to put the first byte of the SD card on the bus.  The Z80 will then read this, write it to RAM and signal to the ‘328 it wants the next byte.  And repeat until done then set the Program Counter to the address in RAM to execute the code.

I have deliberately chosen a request/send model so that timing issues are avoided – partly because I don’t know if there would be timing issues, and partly because one of the things I would like to do is run the Z80 very very slow (so I can see what is going on), and this should still work.

Initially, I will gloss over the issue of file size and memory location by assuming a file size of 1k (with the ‘328 padding with FF to make up the balance) and that all programs are run from 0x8000.  I can, if needed, add in a file on the SD card that defines these parameters that the ‘328 can send as a preamble… but we’ll cross that bridge when we get there!


by Spencer at 15 September 2014 07:06 PM

Martin Raynsford hackergotchi for Martin Raynsford

EMF Camp - Vodka Roulette

I thought I was at the end of the 'things made at EMF camp' but then I remembered I actually cut some stuff for myself while I was at EMF camp. It's probably because I prepared most of the things in advance but they were cut and assembled at EMF camp so that counts right?

I've made flavoured vodkas before by dissolving boiled sweets into vodka and coming up with some pretty tasty flavours. This year I thought I would go one step further, I made 5 sweety flavoured vodkas and 1 nasty flavoured vodka and being a field full of tech geeks I figured they would appreciate a mechanism to automatically select a flavour for them. In brief, an arduino uses the random function to pick the appropriate bottle. A row of surface mount LED's illuminates the bottle selected and these are driven simply with a ULN2008 driver chip. The LED's spin round in a circle and fade in and out as they are selected. The rotation slows down and picks one bottle to end upon.

I'm not sure the random seeding from the A->D is particularly effective and I was basically resetting the power each time to make it spin again so it had this weird habit of picking the nasty, Horse Radish, flavour every time but that just all adds to the fun.

by (Martin Raynsford) at 15 September 2014 01:31 PM

14 September 2014

Spencer Owen hackergotchi for Spencer Owen

RC2014 with ZX Printer interface

My original plan had never been to design and build my own computer.  I had, however, planned to build a clone of the Sinclair ZX80, which has been on my bucket list of things to own for year, and which I had found plans for online.  Whilst collecting the parts and reading up on simple Z80 computers I got kind of sidetracked and ended up with the RC2014.

The print out shown was what was left from the last time this was connected to a ZX Spectrum!

The heart of the RC2014 is a Zilog Z80 CPU, which is the same one that Sinclair used in the ZX80, ZX81, ZX Spectrum and Z88.  If the ZX81 and ZX Spectrum can run a ZX Printer, then surely it follows that the RC2014 will be able to too?

The RC2014 backplane brings out nearly every signal that the ZX Spectrum has on it’s edge connector, so a simple adapter from the 0.1″ pin header to an appropriately laid out edge connector should suffice.  The only signal the RC2014 doesn’t have is 9V which is used to drive the original ZX Printer, so I added a connector for that to be injected in.  (For my use it isn’t strictly needed as I’ve got the Timex/Sinclair 2040 (also sold as Alphacom 32) which takes it’s power from a mains adapter, not the edge connector, but is otherwise totally compatible)


i (1)

So, I soldered the connector on, plugged it in and expected things to work.  But, no.  I had Odd Things™ happening, and couldn’t get much sense out of the serial interface.

It turns out that the ZX Printer uses very very minimal address decoding.  Basically, if the IO address line A6 is low, then it has the data bus.  The only thing I had connected to the IO of the RC2014 was the serial interface, which although it only had a small amount of address decoding, it did use A6 in a low state.


So, a little bit of thinking later, I realised that the easiest solution was to put some decoding on to the ZX Printer adapter so that it would only respond to a more specific address.  Luckily the design of the RC2014 backplane meant that cards can be easily extended with a bit of Verobaord.


Here’s the modified board with a 74LS10 that brings A6 low only when A0, A1, A3, A6, A7 are high.  Therefore I can address the printer from port 203 (0xCB)



The control of the printer is very low level indeed (ie ever so simple, thus complicated to do!).  Early tests have shown that I can print lines of different lengths though!  I consider that a #WIN but will see if I can get a dedicated print driver written for this.

by Spencer at 14 September 2014 07:34 PM

Martin Raynsford hackergotchi for Martin Raynsford

MSRaynsford Gift Cards

"Alex Bailey requested a laser cut gift voucher for his dad, Adrian" ;)

So that was basically it, but I realised it was a good idea and agreed to make him a little laser cut item to represent a gift card. This all happened weeks ago but given the recent spate of catapult fiddling you can see how the two get connected. You get some instant gratification in the form of a mini catapult which you can assemble while you wait for me to ship the item you pick from my blog (this includes customised items).

If you would like a giftcard simply copy the file I shared last week, change the wording at the bottom and return it to me

Both giftcards and catapults are available from the same listing

by (Martin Raynsford) at 14 September 2014 02:10 PM