At a dinner party a few months ago, the host asked if I could repair their go-kart, using my RepRap 3D Printer. Apparently the steering wheel had broken off and the Chinese supplier refused to supply only the steering wheel. I accepted the challenge, but did warn that PLA was not the ideal plastic for such a repair, being somewhat brittle.

I decided to approach the problem by removing all the broken plastic from the back of the steering wheel, and designing a new part to slot over the steering column nut and bolt onto the remains of the steering wheel.

Having designed the part, I posted it to Google+ for advice. Wildseyed Cabrer suggested that I do away with the buttresses of v1 and instead design a solid cylinder. Of particular interest was his suggestion to use pinholes around the nut hole, to force the slicing program to add reinforcement. Andreas Thorn reminded me to use the $fn = 6 for the chamfering of the nut hole, as I had for the nut hole itself. The Google+ 3D printing community really is amazing - thank you.

Unfortunately printing the item was much delayed by the fact that I did not have the precise measurements. As always I had designed the item to be fully parametric; so that the exact measurements didn’t matter until I came to print. Unfortunately the owners of the go-kart did not feel able to accurately take the measurement; so instead the go-kart had to be delivered to our house.

Having measured and printed the final part, I was delighted that it all worked first time. The only issue was that it was very difficult to turn the wheel and I was concerned that the part would not indeed be strong enough. I noticed that all four tyres were completely flat, so much so that the tyre profile was concave rather than convex. This was clearly putting a huge strain on the steering and may well have been a contributory factor in the original breakage. Having pumped up all the tyres the steering was very much easier.

The repair complete, the go-kart was delivered back to the owners. I have no idea whether the repair will last long enough to be worthwhile, but providing it lasts a reasonable time, it can of course be simply reprinted. We could also consider having it professionally printed in a stronger plastic.

• View design at FabFabbers

Phase 1 of the build of my RepRap Prusa is now complete and I have photographed it thoroughly, to assist others with their build and for general interest.

View Album on PicasaWeb

I have even taken a brief video, apologies for the lack of lighting:

The instructions I followed were the Prusa Mendel Assembly instructions, with modifications described in the Thames Valley Google Groups thread Frame bearing specifics?.

This Prusa is 16mm wider than standard, in order to allow for the heated bed. For further details on the design being followed, please visit:

http://tvrrug.org.uk/

Looking forward to Phase 2 of the build!

I have been following the RepRap project for some time, but it always seemed to me to require hardware hacking skills that were that little bit beyond me.

At Oggcamp 2011 I watched a presentation by Malcolm Napier of empirical on the Reprap project.  Whilst this sparked my interest anew, I was put off by Malcolm’s mention of builds taking months rather than days; as before this seemed to be a project for hardware hackers.

A few weeks later I received an email from Hugo Mills asking me to post an invitation to a new Reprap build event to the Surrey Linux User Group mailing list. The build event was being organised by Malcolm, and would help users to build their own Reprap in a supported way. This sounded perfect for me so, having forwarded the email, I booked a place on the build event.

To cut an unnecessarily long story short - I have now ordered and paid for my reprap parts and am now eagerly awaiting their arrival. There are 20 of us in the first build project and we are hoping to receive everything except the electronics by the end of November.  The expectation is that we will complete the build in January.

If you would like to read more, and perhaps consider participating in a second build project, then visit the very new TVRRUG website, and perhaps start off by reading the First Steps page.

I will try and blog about the experience here, in the meantime we have a fairly active IRC Channel #tvrrug on Freenode if you would like to pop in for a chat.