Help with disc

[geoff]

Guys,
We are starting to talk about some very silly RPM here, just be careful if you are thinking about using speeds like this, are any bearings being used going to be up to the job?
Also remember that any teeth on said disc need to be seriously well attached as at those speeds the forces trying to tear them off the rim are colossal!
I wouldnt want to be anywhere near one of these discs if it spat off a tooth, I know, I have seen a tooth part company from a disc at a mere 5000 rpm and that was quite scary enough thank you!

I am making the disc + teeth CNCd out of a solid lump of steel (therefore teeth are part of the disc)... Im going to get some CADS done of this today...

[ewan]

mmm... not me (my new CNC sponsors are called oldlandcnc) they are going to be making the complete chassis of the next robot (from team Mini-Maul, see http://www.micro-maul.co.ukwww.micro-maul.co.uk, soon to get an update) and believe me, (I just did a tour around their warehouse) they are one BIG company. They will be doing all parts CNCd (YAY Im as good as Ed now ) out of aluminium and titanium...

Im trying to be as professional as possible with the next robot, using the best components I can get for it... It should be good

[fluppet]

That brings up a question Ive been meaning to ask before. Its all very well making the teeth part of the flywheel, but arent they the most likely bit to get damaged? If so, isnt there an issue that if you lose a tooth you need a completely new wheel that way?

Also Id have thought theyd be easier to sharpen if theyre separate, and you can keep several sharp sets handy for switching between matches.

Not that I ever intend to build a spinner (Im too much of a pacifist, and scared), but Id like to know whether Im inventing issues which just arent there.

--
Fluppet

This is fantastic news ewan, but remeber theyll make a really badly designed robot to withing +/- 0.001mm if you ask them to, but it doesnt change the fact that its badly designed. What I am saying is, BE SURE you think the design is as good as its possibly going to get before one of their end mills gets within a meter of any metal. To slightly mangle an old proverb: design twice, cut once.

Be sure... Im being careful...

[geoff]

The only problem I can see with a one piece cncd job is at that sort of speed any tooth damage will cause MAJOR balance problems..you may be better with replacable teeth, but see my last post.

A little bit OT, but the friction drive on Daniel Kerrisons The Aggressor works pretty well. It spins the flywheel up fairly quick with the 300psi Compressor motor and weve seen it damage a few bots, including our own. Just resently it bent 5mm thick tangent teeth on impact with a robot, and we were surprised it was going to even get the much power. I cant wait to see it with the 24v EV Warrior

[jamesb]

is the point not that a solid cnc one piece disc/teeth is not as likely to throw a tooth?