Saturday 28 January 2017

Workshop Preparation and Rocket Motor mount prototyping


Been doing some prep for the upcoming Rocket Design workshop I'm facilitating at Madlab I wanted to replace some of the images I'd used of motor mount assemblies in a presentation as frankly the old images weren't that great/clear... however I've since put the motor mounts into rockets so had to make a new one! I had a spare estes 24mm motor mount assembly which I've knocked up as an example.

It's been a bit of a motor mount week though as I've also been exploring motor mounting for a high power reloadable rocket motor kit I've bought with which I hope to scratch build a level 1 UKRA certification qualifying rocket around. It is the smallest reloadable motor casing that has options for the H impulse motor power I would need to fly to qualify.


The motor kit is a Cesaroni 29mm 3 grain kit and so I've been tinkering prototyping some mount components, again it's really handy having the small CNC to really accurately cut the centring rings and even cut a hexagonal pocket for captive nuts.. I find a 1.5mm endmill is small enough to not leave a radius that interferes with the nut.

So below is the prototype motor mount for the cesaroni kit!.. definitely a step up in size! When I have fully dialed in my design for the level 1 certification rocket I'll essentialy be remaking this mount assembly but using better materials, ply instead of mdf and some phenolic tubing instead of a (surprisingly accurate to 29m ID) tube from some wrapping paper... and applying the epoxy in a much neater fashion!






Sunday 22 January 2017

OzQube 1 Pocketqube chassis work



Regular readers (a very elite bunch!) will know that I have been involved for ages with Stuart the brains behind the OzQube-1 pocketqube satellite for a few years despite us being on opposite sides of the planet! I've finally today made a start on a chassis for him from a blank I accurately sized over xmas. Theres plenty left to do and these small 50mm chassis always throw up some interesting stuff/challenges. Pretty much all the PQ chassis I've been involved in or have made always seem to involve tiny brackets which are a pain to make, working on this and the discussions around it have led me to come up with a PQ60 compatible design which doesn't rely on brackets... it's very much on the drawing board phase at the moment but watch this space for my usual snail like progress!



Tuesday 10 January 2017

Asimov and the Slide Rule Boys



So I am re reading I Robot by Asimov as its a text on an open university module I'm doing. Its great fun revisiting this classic, I love Asimov and enjoy older science fiction as it's always interesting dipping into retro-futurism and comparing it to current technologies and trends.

The first few chapters are told as retrospective narratives by Susan Calvin regarding early issues with robotics.. she is telling stories in 2062 about things that happened to 2 roboticist trouble shooters around now/2017... and of course Asimov imagined this all before publishing in 1950.

So as well as reading what Asimov imagined the future would have created (positronic brains the big one in I Robot) it's interesting to see what technology available in the 1950's he imagined would still be in use in his future world. Enter 'the slide rule boys'. At numerous points the trouble shooting characters, Powell and Donovan, refer to the 'slide rule boys' meaning the engineers and physicists working for USRobotics creating the robots.... and yes.. it's sexist..I know.

For me (and I freely and proudly admit I am a slide rule fan who carries a slide rule every day) I love that Asimov considered the slide rule such an important device that it wouldn't be superseded by an imagined other technology, it is testimony to the device and its standing at the time in the 1950s. Although they have fallen out of popular use, falling prey to calculators and computers, they are fascinating devices and powerful tools for a variety of tasks to this day. The slide rule I carry everyday (as opposed to the larger ones for home use!!) is an Aristo nr89 which can calculate a surprising number of things by manipulating the slides, multiplication and division, tangents and sines, diagonals of squares, inch to mm conversions, circle areas and more and more. Interestingly for me slide rules also gave me a more concrete feel for logarithmic scales... and.. the Aristo 89 has a metric ruler on the edge so is quite handy for ..heck... drawing lines and measurements. :)

Wednesday 4 January 2017

Are makers a movement?



Image by Andrewrabbott - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=43664330

So this post is a response to Adrians post .... short version.. we mostly agree!

As ever feel free to ignore.. although I get involved in maker stuff I don't spend much time thinking about the form it takes so others are much better informed than me and indeed my definitions may be well off the mark. However here is my two penneth worth!..

For me I prefer the term maker culture or maker scene as I feel there is a broad culture of people globally linked by making within which I feel there are movements. For me a movement is when a collection of bits come together to create a unified direction towards a common goal...like when 'movement' is used to describe the bits in a clock all working together to make the hands reflect the concept of time. So I think there are lots of movements within maker culture.. but not all makers would align with all movements. So for example;

I see a lot of movement around restart and repair, from the magnificent restart party through to Make's appropriation of the phrase “if you can't open it you don't own it”. This unifies a lot of makers, from circuit bending re-users, to people designing and making ethically sourced repairable embedded systems, to those coming up with ways to reuse plastic bottles.

I see movement around localised production/manufacturing with global design, the fablab idea etc. This movement has a lot going on in it but those makers immersed in areas with lots of manufacturing opportunities might not align with it as a movement as they don't see a need. For example I doubt I'd have thought about PCB fab houses and the ethics and complexity of making at home versus using a UK fab house or euro manufacturer or a far eastern company... if I was a maker based in Shenzen...whereas as a maker halfway up a mountain in rural North Wales I do!

Citizen science, lots of makers I know are involved in citizen science projects and this could be considered a movement within the maker scene, as could many other areas, crypto currency, OSS/FLOSS, renewables, energy monitoring, opendata ...I could go on and on..

However some people are makers purely out of an autodidactic playful trait, in that they tinker with arduinos/launchpads/espxxxx/picaxe/fpga or PCR/geneslicing or CNC/lasers/routers/3dprint or diyspace/satellites/radio/rockets or hand whittle a bowl/spoon just because they want to learn and play with no particular end goal or aim... and this is where making seems more flaneurial than a movement to me.

So why does this subject catch my attention, well the difficulty for me considering the whole of maker culture a movement, is that I feel it could alienate people.. I know plenty of makers who just make. I was chatting the other day with a person who was telling me about their model trains and how they had created a massive logic gate control system for it.... for their own pleasure.. I certainly class this person as an archetypal maker... but part of a movement?... I'm not sure. If movement and common aim becomes the core of maker culture.. do we not kill off its aimless wandering vagabond spirit of freedom?

Thanks for listening. :)