One thing you could try is the way I have just made a set of toothed belt pulleys for my new little gantry mill. I used 'Polymorph' (Jett Sett) and the way I did it was to get a long belt of the pitch I wanted and a bit wider than I intended to use. I chopped a length off htis of the right number of teeth for the pulley being careful to cut it at the root of one of the teeth so that, when I put the ends together, the pitch was maintained. Now I turned a recess in a piece of metal or acrylic ( I used scrap bits of both for different pulleys) so that the belt would just fit into the recess with its ends tightly butting - that was the plan anyway but I actually ended up with the recess a bit larger in diameter and shimmed it down to size with paper strips. I drilled the centre of this mold and put a peg in of the diameter of the shaft the pulley was to fit and then turned a brass hub for the pulley with securing screws and a knurled section which would be inside the pulley.. Now it was just a case of filling the recess with the thermoplastic - dunk the plastic beads in very hot water until they turn transparent and coagulate into a lump - fish the lump out and knead it in your fingers to get the trapped water out, then press it into the mold like plasticene forcing it first into the teeth of the belt with something like a screwdriver blade, then filling the centre. This is much easier to do than to describe!! I didn't bother with cheeks on my pulleys and they run fine without shedding the belts but, if you need cheeks, you can just turn up a couple of disks if thin metal and bolt them right through the pulley - warming them a bit first will set them flush against the sides of the pulley. The finished thing is an exact fit to the drive belt and is of a tough nylon consistency. This is the easiest way I have found to make the pulleys but, if you really want a metal one, this would also be a good first step as you could measure from this the exact OD required and use it to gauge a formed flycutter while you make it..
Ian _____________________ Ian W. Wright Sheffield UK ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
