All posts by matt

About matt

Matthew Venn is a director of Bristol Hackspace, a freelance engineer and computer science teacher.

Sab’s Spoons

Sab has been making spoons on a CNC router. He put a photo of an existing he liked the look of into Blender , and then tweaked it. Later he used Vectric, which lets you choose the texture.

Here are some of his prototypes:

and here’s the current version, before finishing (Sab rather likes the diagonal lines):


The key, he says, was a combination of parameters and tweaking until he got the effect he wanted. Vectric has a free time-limited trial, which was very useful as he could simulate the shape and texture without having to come down to the Hackspace.

At the regular Hackspace open evening on thursday he was discussing with Richard and Anton how to finish the spoons. His original plan was to finish it by hand: Richard’s suggestion was a fine and fast last pass on the router; Anton suggested buffing it with a wheel and Tripoli.

Here’s  the CNC router he used:

Pictures are all by John Honniball:

9 year old says first Shonkbot workshop ‘Epic’

Thanks to an amazing team effort from Richard S, Libby, Barney and Zak (am I missing anyone else?), the Shonkbot (our attempt at a cheap and easy to make robot) has developed into a great workshop. The team got a chance to test the robot out with children aged between 8 and 13 at DigiMakers this weekend.

Participants worked with cheap and widely available parts:

IMG_7131Followed some (still improving) instructions:


And used plenty of hot glue to create their Shonkbots:


At the end of the workshop, all participants had successfully created their robots. Some had added the more advanced obstacle avoidance components.

Even though the kits ended up at £15 (our original target was £5),  all of them were bought to be taken home and reprogrammed!

Check the rest of the photos here and here.  Instructions and code are on the github.

Great work team Shonkbot!


John Honniball; Electronics Whisperer

Richard brought in a couple of dead oscilloscopes in case they could be fixed. The slightly newer one (last PAT tested in ’96) couldn’t be focused.

John quickly realised that one of the resistors was not like the others:
John H was Very Suspicious of this resistor, and replaced it. Once replaced, the scope worked perfectly! Luckily for us, John was able to explain his abilities:

I saw that it had been replaced, yes. But I also saw that the ‘new’ part was a carbon composition resistor (they’re a slightly different shape), and therefore an old-stock part. Carbon resistors don’t work well in high-voltage circuits, and this focus circuit is certainly at hundreds if not thousands of volts. All that made me suspicious:

1. In a high-voltage circuit.
2. In the focus circuit, and that’s not working.
3. Been replaced before.
4. Been replaced with unsuitable replacement part.

And then I cheated, and measured it with the Ohm-meter. Should have been 2.2M Ohm, was open-circuit. That clinched it. We didn’t have any 2.2M Ohms, so I fitted two 1.2M Ohm in series. Didnt unsolder old part because it was under the CRT, and open anyway.

Thanks John!

Glass etching workshop pics

Here’s some photos of the glass etching workshop that we ran recently. Thanks to all who came and made it a success!


Some quotes:

Using and learning new ways to do an old craft.  Felt like a true co-operative rather than a profit making ‘course’. Thank you.


A hands-on opportunity to learn a new skill.

Woodworking with hand tools skill share

skillshare Tuesday 7th July. Doors will open from 6.30pm for a 7pm start. 10 tickets available.

Woodworking with hand tools. An introduction to using hand tools such as planes, chisels, saws and scrapers; and how to keep them sharp. I’ll introduce a variety of different hand tools with a brief explanation and demonstration of each.
I’ll then get the participants to have a go at planing rough sawn timber, sawing squarely and accurately, using a chisel to make a housing joint, and sharpening a chisel.

Eventbrite - Woodworking hand tools


After Makerfaire 2015 we were really impressed with how much time and effort had gone into lots of projects.  Really polished and professional looking demos.
This is great, but it can also be off putting for beginners who might feel unable to get started.
 So we want to answer that by developing a £5 robot that is quite bodged together.
Probably based on a shrimp kit, using steppers or dc geared motors and a CD for a base.
To keep it accessible we won’t be using any PCBs or anything laser cut.
It will draw with a pen and maybe communicate with other robots. Here’s a video of what we’ve got so far:

Glass Etching


Tuesday 2nd June. Doors will open from 6.30pm for a 7pm start. 12 tickets available.

Learn how to etch designs into glass using acid etching cream. We’ll use a Craft Robo vinyl cutter to cut out a vinyl stencil, then transfer that stencil to glass and etch the exposed glass using acid cream.

Please bring:

  • A laptop. If this is not possible please bring your design on a USB stick.
  • Glass to etch. This can be anything made of glass, but it cannot be curved in two directions. That is, cylinders and cones (tumbler, martini glass) are fine; spheres (wine glass) are not.

Here is an example of what you might make:

Eventbrite - Glass Etching

Arduino workshop prep and sharpening tools

Some of the wood lathe chisels had got blunt so Anton took them home where he has a jig ready to give the chisels the right shape again. We’re currently discussing which grinder to upgrade to, and it seems it might be a good idea to get one with a jig for these tools.

Anton has reground the wood-turning gouges, and they are back in the space.

Our latest skill share workshop is using 10 Arduinos and a Raspberry Pi. We bought a brand new bunch of 10 but wanted to make sure they stayed at the hackspace! Joe kindly offered to design a board to hold one alongside a breadboard. We think they came out great! Thanks Joe!


UK Makerfaire 2015!

A few hackspace members braved the long journey to Newcastle to attend the UK’s biggest makerfaire. We all had a lot of fun, saw some great stuff and met lovely people!

Here’s what we took…

David Henshall was showing off his mini mill cnc, which is a plywood 3 axis CNC. It’s designed as open hardware that can be made from scratch or ordered as a kit.


Richard brought his tune on a stick – of EMF camp fame


Matt brought his energy wristband project, and had it hooked up to a miniature fake home so people could play with turning on and off appliances.

And finally, Anton brought giant sketchy – a giant delta style robot that’s powered by an Android phone to draw your portrait!

More pics from Richard can be found here, and some from Matt are here.