Speedster wrote:Yes, l have tested many vendors wheels for roundness and a few days ago I ordered another set from each of 3 vendors for testing. I'm going to see if I get the same results as last year. They are all the basic wheel where nothing has been done to them other than trying to make them round. The wheels are not always round. I consider a wheel round if the needle does not touch the .001 mark. The point I was trying to make is if the vendors with their expensive equipment, their skill, and their livelihood depends on making a round wheel and they can't do it, that should tell us something. I'm on your side. I really am. If you can make a piece of equipment for less than $100.00 and can make a wheel round in a sensible amount of time, my hats off to you.
I look forward to reading more about your project.
I know at least one vendor that guarantees runout to be something like .0005" or less, so if I bought wheels from them and they tested differently, I think I'd want product replacement.
Part of me thinks that posting results of vendor wheel testing would be a service to the PWD community.
Anyhow, here's the thing: I tested wheels cut by a racer who was kind enough to send me some of his worked wheels and they were under .001". I know what machine he uses and it's probably about a $600 lathe. I also know that Stan has cut some very good wheels on his Harbor Freight cheapie. It's interesting to me that you're getting vendor produced wheels that are not so great, but maybe the issue at hand is not so much a question of ability, but a question of quantity. I have no idea how many wheels a vendor has to produce, but usually there's only one guy doing it. If you have to rush production, well, i would imagine that quality can slip. Just a theory, though.
Anyhow, I'm currently stalled out while waiting for my collet to arrive. Thing ships from China, so it might be a few weeks. Have been thinking ahead to the other problems I have to solve, if the pin-in-collet actually manages to spin true. (If it doesn't, well, no sense in proceeding any further).
First problem: Tool holder. I am probably going to plod ahead with the homemade X-Y table, fused together with metal-laced epoxy. The investment for the parts is very low.
Second problem: Propulsion. I think I'm still leaning towards using a Dremel-esque tool with adjustable speed to drive the thing. Harbor Freight's got one
for like, 20-25 bucks depending upon whatever specials they are running.
Third Problem: Power transfer. I need a way to make the rotary tool spin the shaft. For this, I'm thinking of getting (from Shapeways.com or similar) some plastic pulley guides printed. One will go on the shaft of the collet rod, and the other will go on the end of a rotary tool shaft. This will allow me to choose a size ratio that will spin the rod at the right speed threshold for working polystyrene wheels.
These are all just musings for now, but any thoughts on my thoughts (so to speak) are welcome.