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I've had a thread running on radbmx.co.uk for a while so I thought I'd share with you lot.

Heres the deal, I'm a model maker and I've restored a few bikes. I've been making DX endcaps for people for a couple of years to help fund builds.

As I'm running out of space and more bikes costs more money I thought I'd make a 1/3 scale model.

I started with the seat and tyre as my theory was that if I could make these two components the rest would be easy as the seat was going to be a bit hit and miss. In other words i had to freestyle it until it looked right and the tyre was also a bit of a headache being that I decided the best way would be to make the knobbles and stick them on seperately.

The seat was made from a vac forming, I had to make a former slightly under sized to allow for material thickness then the shape inside was made. The rails are bent from steel rod and the guts were made on a lathe, I made all the little parts then cut the head off a tiny bolt and put nuts on the ends so it actualy works like a real seat.

This first pic is the former (grey) and the seat.









Then I gloss lacquared it then masked the sides and matt lacquared the rest.





Next was the tyre, heres some pics of the knobbles being cnc machined. First I had to machine in all the little slots and dots then I turned the material over and machined the scoop on the backs of them with a bull nosed milling cutter so they would sit nicely on the profile of the smooth tyre that I turned on a lathe.







In this one you can see the three different sizes of knobbles on the tyre.  middle, inbetween and outside.



This is them being stuck on. I marked 80 (I think, I can't remember now) points on the tyre and stuck on the middle ring first then went from there.







After that boring job the tyre was moulded in silicone and cast in black resin. It will obviously have skin walls and logos when the bike gets finished.





The skyway was drawn using CAD then CNC machined in 2 halves.  Then it was stuck together and again moulded and cast. The hubs haven't been made yet but they'll come soon.







The bars were made from brass so that they could be polished and chromed. The crossbar was silver soldered on. They're SE powerwings by the way.







The stem is a TUF NECK and made from ally with little bolts that work as a real one would. The tiger head logo will be lazered or cnc machined on at a later date.





The frame and forks were next, I used a green model board which in laymans terms is a very posh mdf.  I made all the section and glued them together then used sculpting wax to make the welds. Then it was all molded and cast.









Heres the dropouts before they were stuck on.













Heres the frame being cut out of the mould.



This is the frame after getting it out of the mould, you can see how bust up it is and the wax welds.



This is the resin casting.











Heres a pic of some spare castings I've got.



These are the cranks, they went a funny colour from the heat.

I made them form brass and silver soldered the tubes in, they need cleaning up then polishing then chroming.











In these latest pic I've sprayed the f+f with 2pac primer.
i've knocked up some makeshift hubs just to get the wheels on for the pics but I'll do the ally hubs soon.












So thats about how far i've got. I've been laid off from work too but still have access so I'll still be able to carry on with it.

If anyone wants to talk to me about doing one for them then I'd love to discuss it baring in mind it wouldn't be cheap as there as so many hours involved. Obviously a bike with the same parts that I've already moulded would take less time than doing one from scratch.

And heres a little advert of my stuff to sell.





1/3 scale kashimax aero seats.  $9 shipped.

And shimano dx end caps.  $22 shipped.



This is a pair.






Thanks for looking guys, hope you enjoyed the lesson:D

Joe

Last edited by rakas17 (2009-02-28 4:47pm)