Friday, 19 July 2019

Rocketry Series Part 2, OpenRocket Walk Through.

In this episode we walk through a quick rocket design in OpenRocket and then simulate its flight. OpenRocket can be downloaded for free here 

Wednesday, 17 July 2019

Speaking at a Local Apollo50 event... I got to hold the moon!

Last night I spoke locally at MSParc a new science park building purpose built on Anglesey North Wales at a great event co-ordinated by MSParc and the local Dark Skies project. The event was family friendly and included a planetarium, some STEM activities, Dark Skies project info, displays of meteorites and local Astronomers showing off their excellent kit and work.

It was well attended and I was booked in to show some of my rocket on display and also to do a talk on SatNOGS and Librespace. It all went very well and was well received by a pretty fair sized audience for 6pm on a tuesday evening. What was really unexpected for me (as I hadn't read the full program!) was the final speaker booked after me was Dr Margaret Wood who spoke about her amazing career. Dr Wood has many accomplishments but in her early career she headed up a laboratory at Manchester University which was the most capably equipped laboratory in the world at the time to process and analyse the moon samples returned to earth by the Apollo missions. She spoke about this work and it was wonderful to hear and then she proceeded to produce some tiny grains of moon samples from that work (once Dr Wood found them in her hand bag!). It was an unexpected and brilliant end to a fab event to be able to hold a tiny speck of the moon.

Thursday, 11 July 2019

Rocketry Series Part 1, Model Rocket Overview.

Just uploaded a video talking about model rockets, general overview stuff hopefully the first of a series with some more videos to follow on designing, running simulations and scratch building rockets.

Sunday, 7 July 2019

Hand drill restoration.

So this had been my "ten minutes here and there" project this last week. I've had this old hand cranked drill for years and its been neglected and was ripe for a clean up. 

It was essentially in good condition but a bit rusty and faded so a quick strip down and repaint was about all it needed. Removing the spindle and chuck was slightly challenging as the pinion gear was held on with a press fit pin through the shaft which needed drifting out with a fine pin punch.
Quick sand down and ready for paint, I did consider staining the handle but after a sand it was quite pitted and not the nicest grain so paint seemed a better option.
Bit of paint and not being to precious as its a tool to be used not so sit on the shelf! 
Refitting the pinion pin and I was reminded why I adapted my little arbour press ram to accept and hold 10mm diameter tooling, it means I could just about reach in to get the pin refitted.
And there it is.. all ready for another stack of years of abuse! 

Thursday, 4 July 2019

Perfecto Shaper update, made the missing part!

Just posted an update video to the youtube channel with a video update on the Perfecto Hand Shaper having made the part which was missing, check it out and as the tubers say.. don't forget to subscribe!

Tuesday, 2 July 2019

Liverpool MakeFest 2019

Had a great day at the mighty Liverpool Makefest It was great to catch up with a lot of people and see some amazing projects. I'd tweeted about wearing my SatNOGS tee shirt and was really pleased that lots of people wanted to catch me for a quick chat about that project, Indeed the very next day DoEs Liverpool got a simple SatNOGS station up and running. Anyway... here is a quick round of photos with some quick notes in no particular order! 

So the first people me and my daughter chatted with were the mighty #GirlsWithDrills crew. I've been a fan of their vital work to make maker culture inclusive, equal and equitable. Bought my daughter a tee shirt and after a fab chat went in.

Quantum technology club has an amazing sign that did music and light sequences and was very cool. Brilliant to see this lot were talking about radios, had a CW (morse code) practice activity set up and had an SDR setup etc. They were really keen on the SatNOGS project and also chuffed to be introduced to HackSpace magazine and started downloading digital editions whilst we were chatting! 

Coretec robotics! Stallwarts of maker events throughout the lands, great to catch up with them and Seren enjoyed working through the make a flying spinny disc activity (build a simple driver circuit, connect it to a Pi, write/code a simple python script to spin up a motor to launch a flying spinning disc). As usual Coretec had a plethora of amazing robot builds including a nice balancing one seen below.

This 3d printed shelf bracket is one of the many amazing things on the little sandbox stall. This project is typical of little sandbox and shows how brilliant they are... They get their young people to design and build things like this that become part of the spaces they use, it helps create a sense of ownership for the young people over the project as well as teaching them some skills. Fab. They are also actively pursuing SatNOGS as a project and Rocketry... LEGENDS!

Around 11 am and the bottom floor starting to fill up.

Fabulous racoing game... the brio track has been fitted with neo pixels and the controllers (to make your pixel travel round the track) were those hand crank generating torch things. It was a fantastically playable game... I loved the details such as you needed to crank harder and generate more power to get up the hill or you would roll back and you would then accelerate on the downhill... Brilliant. 


York Hackspace as ever had some amazing stuff on display including this gorgeous Altair 8000 project!
 Above and below... 2 different versions of the classic snake game... It really entertained me that at Makefest you could play 1 dimensional, 2 dimensional or 3 dimensional snake in different parts of the show!

The fabulous Lorraine with her Cubert project right by the front door! A busy day for her with a fabulous project.

And finally Mark Mellors and his Hacky Racer, I got to have a sneaky little go and I have to say a Hacky Racer project is definitely on the list of future projects.

So there we go.. a great day out... If you haven't been to Liverpool Makefest you really should... it's fab!

Tuesday, 25 June 2019

Perfecto Hand Shaper, A Little Walkthrough

Just added this video explaining a bit about the Perfecto Hand Shaper and how it works and what I am planning to do to restore it after a couple of people asked for a video on twitter. I've decided to start using youtube for uploads moving away from Vimeo so as such feel free to like and hit that subscribe button!

Thursday, 20 June 2019

Vintage Tool Project, Perfecto Metal Shaper (pt1)

So I've been teasing all day on twitter (Follow me here!) that I had scored a vintage tool that I had wanted for a while. And here it is! It's a hand powered Perfecto Metal Shaper. I'm really pleased to have found it at a reasonable price and it couldn't have been more local as it turned up in my village. I had wanted a shaper for a long time and kept looking at the small Adept ones which sometimes crop up on Ebay and sell for quite a lot of money. This Perfecto one is even better for 2 reasons, one is it has an automatic feed which many of the Adept ones don't have, so that with every stroke of the tool this one will feed the work piece to the left or right meaning you can concentrate on cranking the handle and not having to reset the work every stroke and..It's a Perfecto!  The reason I am excited it's a Perfecto is because the larger of my two main lathes is a Perfecto (the larger heavier 4" swing one they did)  and mine came from the AVRO factory. I don't know the heritage of this shaper or where it has spent it's life but I am pleased to have one of the few other types of machines Perfecto used to manufacture. Shapers are less common in the workshop these days but historically before Milling machines became more accessible they where a go to tool, they still can be incredibly useful for certain types of job. If you are interested in reading how these machines cut and shape metal Wikipedia is a good place to start and there are lots of YouTube videos of shapers, powered or hand cranked showing how they work. 

So it's a bit of a project/restoration, It all functions pretty well but would certainly benefit from a strip and a clean up, it has one part missing which is the rear travel limit block which also moves the ratchet on the automatic feed mechanism, but it is a pretty simple part to fabricate and I have the other one to use as a pattern. I'm sure I'll find a few more issues but don't think it's hiding any big problems.

I am aware that these shapers were made from the 1950's through to the 1980's and I am guessing that this is a later one as something about the way the graduated dials are printed rather than engraved hints at this. I will scour around for a method of dating the machine based on the various serial numbers all of which are present on the machine. 

So as time allows I will crack on with a restoration of this machine and hope to put it to good use. Stay tuned for updates. 

Monday, 3 June 2019

Review of Machine-DRO Height Gauge

When I knew I was going to have to write an article on marking out metalwork for Hackspace magazine I decided it was a good time to update my very old second hand vernier height gauge. My old gauge could be made to do accurate work but was very fiddly and it hard to photograph the worn markings on the sliding vernier section! So I bought a digital height gauge from a company I found online called Machine DRO which is part of a wider group of companies called the Allendale Group. I went for the 300mm variant which is currently £73 including VAT but I notice there is a more affordable smaller one as well which was tempting, however I imagine at some point I will need the capacity the 300mm one affords.

It arrived quickly and very well packed with a good polystyrene fitted cover that meant it couldn't move at all in transit. I fitted the supplied battery and away we go. It has a precision ground base as expected and so it glides well across a surface plate or table (or polished granite in my case). The display is quick to refresh and responsive. The scribing tip is good quality and makes clear fine marks well into sharpie coated material. The ability to zero the gauge on say a centre line of an item and then create parallel lines above and below the line of known accurate location is superb and the fine feed screw adjust makes it trivial to set the height gauge accurately.

It also comes with an alternate tip which is a universal accessory attachment, it has an 8mm hole and a clamping bolt which can be used to attach items primarily useful to attach a dial gauge or dial test indicator to for consistency or comparative measurements. I'm really pleased with it and would definitely recommend Machine DRO, as an aside I do like it when companies have both Paypal and card payments and also are on twitter! Follow them here @machinedro

Sunday, 26 May 2019

A quick make, 3d printing threads.

I've had this piece of plastic tube for ages, I use it to protect my small model rocket launch rail rods that need to be kept straight and protected from bends. It has had numerous bits of gaffa tape over each end which had slowly turned it into a sticky mess. I've been trying to get to grips with 3d printing threaded items, it's been a challenge until I realised I was expecting to much by applying machining tolerances to the 3d prints. Once I started under sizing the internal threads by around 0.25mm on the radius I started having some success. So now my rod protecting pipe has a nice end-cap one end and a screw lid on the other and I've learnt some new stuff on the journey!

Friday, 24 May 2019

Hackspace Magazine! Keeping track of my articles.

It's been a privilege to write for the Raspberry Pi foundations Hackspace Magazine since last October and I have been meaning to create a post about various articles I have written but never got around to it. So I thought I might create this post with links to all the issues I have article in and a little description of the articles and keep adding to it as (hopefully) the articles keep getting commissioned and published!

Issue 12, Where it all began! I had a "design your own rocket" tutorial in here using the amazing opensource Openrocket design and simulation package.

Issue 14,  An article on Manual Milling machines and beginning machining.

Issue 15, An article on Lathes and their use and a review of a Neke Laser Engraver.

Issue 16, An article on Making a multi headed screwdriver using the lathe and mill and a review of the Eleksmaker Eleksdraw pen plotter.

Issue 17,  Part one of a two part introduction to laying out PCB's for professional fabrication with Kicad.

Issue 18, Big issue for me this one! I had the feature article on Space, featuring lots of maker/amateur satellites, a focus on Libre Space Foundation and a tutorial on setting up a SatNOGS ground station. Also had a tutorial on making a "Slim Jim" antenna and also the second part of the Kicad two part tutorial.

Issue 19, Tutorial on Marking out and Centre punching accurately for metal work and I also wrote the space of the month article on the fabulous Prishtina Hackspace.

Issue 20, Tutorial on Drilling and Tapping threads.

Issue 21, Tutorial on making a Stud Clamp Tool.

Wednesday, 8 May 2019

DIY Screw Switches for Rocketry

In high power rocketry its good practice to have some kind of keyed switch or remove before flight system that isolates the avionics from power. Important as often these systems are connected to small wells filled with explosives that are fired at points in the flight to split airframe sections and deploy recovery parachutes etc. Isolating the system (killing the power) enables the flyer to handle, carry and prepare other aspects of the rocket and only arm the system when necessary.

I've used small 3.5mm stereo jacks and sockets and when the stereo jack is removed 2 pins are connected under a spring steel load to which I have soldered a power cable. I have also experimented with rotary key switches. I have never flown key switches and recently read about some failures using rotary key switches and I've always wondered at what force/speed would it be possible that my clamping stereo jack socket might separate in flight and and kill power?

I then came across the idea of screw switches. A screw switch essentially is a system where a circuit only becomes connected when a screw is tightened. They are often made by hand by epoxying a nut onto a metal bar which is insulated and another metal piece added on top which will be connected when the screw/bolt is tightened. I wanted to try and make one that was accurately repeatable so I could make a multiples but also smaller, tougher and neater.

So I quickly decided on using double sided copper clad fr4 and a PEM nut press fitted to one side. I CNC routed the boards with a hole to receive the PEM nut and 2 holes for M2 mounting bolts. As the M2 mounting bolts would connect the 2 sides of the FR4 I routed a clearance area which generously clears the head of the M2. I fitted a PEM nut (press fit using a 1.5 ton arbour press) to the first prototype and continuity checked that the two sides of the board where still electrically isolated. To make the switching screw I have epoxied another PEM nut onto an M2 bolt and when fully tightened it connects the 2 sides of the board. On the other end of the M2 bolt I made a small punch mark to disrupt the last couple of threads on the bolt which means it cannot be fully unscrewed.

As the device is copper clad I routed the board to have a tab on one end  (at the top of the picture below) onto which power wires can be soldered either side. Therefore when the M2 bolt is fully tightened it connects the wires and allows current to flow.

It then just needs to be mounted in a position inside the rockets electronics bay where its possible to have a small hole in the airframe allowing a small screwdriver to be inserted to open and close the switch. As a mockup I made a small 29mm bulkhead and added a standoff to mount the switch too.
Finally one of the great benefits of a CNC is repeatability, I have now knocked up a few of these and they sit awaiting deployment in upcoming rocket builds.

EDIT!! So some people where asking questions and struggling to see how this worked so I've done a little video explanation and demo! 

DIY Rocketry Screw Switch from concretedog on Vimeo.

Saturday, 23 February 2019

DIY mini vacuum former

I've been meaning to make one of these for years and in amongst everything else I found a bit of time to do it the other week. It's a simple build of a box with a very holey lid - it's ace owning a small CNC as this is precisely the kind of job it's worth its weight in gold for. A quick measure of my cheap shop vacuum nozzle diameter (an Argos special that has lasted years despite abuse) and the CNC cut the side sections to match. I'm experimenting with recycling milk bottles at the moment and using a hand held heat gun. It works well and pulls a strong seal around objects. I fancy trying to make some lightweight small nosecones next to see how they compare in weight to the very thin walled 3d printed ones I have made. 

Tuesday, 12 February 2019


A snowy welcome on the saturday!

 The huuuge keynote by mad dog. Amazing sight!

I was incredibly lucky to go out to FOSDEM as part of the Libre Space Foundation (LSF) team the other week and despite lots of snow and travel disruption had a great time hanging out and working over in Brussels. It was my first time at FOSDEM and I was blown away by the worlds largest conference. It was fabulous to be able to move around and see and meet the teams behind some of the most prevalent open source software, debian, opensuse, grafana, gitlab, nextcloud and so many more. As currently I am freelancing mainly as a writer I made sure to have a little chat and express my thanks to the Libre Office team, whilst it might not be the most exciting platform in the world it does provide me with the basic tooling to earn my living!

Above, the Gitlab team who have been great supporters of LSF. 

LSF/SatNOGS contributors meet the Grafana team (and inform them of an Influx db bug they found!!)

Going out early the LSF set up camp in a large apartment (The Mansion) and LSF contributors poured in from all over europe staying a while to have meetings, hack on code and discuss development face to face. Its astonishing, humbling and exciting to see these volunteers pour their considerable skills into LSF project. As a more mechanical guy it was hard to follow much of the development but everyone was incredibly kind and patient and willing to teach others. Very affirming. (Although there was some discussion around rocketry hardware which funnily made me boot my tiny laptop to show how my ematch ignitor circuit works!)

Team... looking tired on the Saturday night!

Flying Ryan air means taking the worlds tiniest laptop!

A busy booth

FOSDEM was incredibly busy and I spent some time each day helping on the LSF booth, speaking to a constant flow of people from all over the planet about our missions to democratise space and provide open hardware and software to enable people to get involved. Hopefully it results in more people supporting what we do but also I feel sure that certainly a few more people are interested in moving towards setting up their own SatNOGS groundstations on the global network.

General picture dump..

Loved this!

So many LSF people! All in to see Alex Csete talk about our SDR makerspace project

Wednesday, 23 January 2019

Project Roundup!

Been a while since I posted here so thought I might get the ball rolling again with a little round up of current projects I am tinkering on. Above is a picture of a planned level two rocket build I am starting to work on as it would be great if I could get my L2 certification flight and exam done this year and also pass my RSO (Range Safety Officer) as well. That would mean that it could be possible for me to officiate over other people HPR flights but could also look into the possibility of running a launch event more locally?

I've also on an off since before Xmas been tinkering with some odd parachute designs, first playing with plastic and tape and now moving to making a ripstop nylon version. These hexagonal annular parachutes fly quite well, have low side loading and seem very strong due to the way the shroud lines continue over the canopy. I'm slowly developing more skills and knowledge around recovery/chute making and have a few other projects I want to explore.

I've also been tinkering on and off with a simple GPS tracker design using a NEO6 gps board and  HC12 radios. My current off the shelf GPS tracker (works on mobile network) is too large for a 29mm rocket airframe I am considering and therefore this route gives more options in terms of getting it to fit. The tracker currently spits whole NMEA sentences which are received by another HC12 hooked up to the one note mini laptop and the whole thing acts as a wireless serial bridge. 

Finally been making, machining and tinkering with various things to write some more articles for Hackspace Magazine, I'm really enjoying the writing and hopefully the articles are being well received! I'll post a roundup of articles out so far after the next issue with some of my work is published.