Former Colex user trying to learn my ShopBot. RPM Speed Question

[Minuteman Graphics Fayetteville NC]

What is the max RPM I can run my table at, I have a PRSalpha 4 x 9 Gantry, I believe.

I am trying to get the glassy edges on acrylic, that I was able to get on the Colex table. I am pretty sure, I was cutting at 25-30000 rpm.

But, I am not sure I can run this spindle that fast. Seems the previous user has his RPMs all set at 18000

Thanks!
Dave

[coryatjohn]

If you have the standard spindle, the top is 18k. You should be able to get the same effect by slowing down the feeds.

[Rob Gunn]

A couple tricks that I learned on acrylic. I start with a wrought pass leaving around 0.05". Then finish pass to size cut as a climb cut, high RMP and fast travel. Then use a torch on the finished surface to just barely melt material (flame polish). This will give a great edge finish. You may want to experiment on some scrap material to test what works out best.
Take a look at this link:
https://www.youtube.com/watch?v=Mmd56UMHDK0

[EricSchimel]

That’s a good suggestion Rob. I do a similar approach with decent results. With a little tuning you can get pretty decent quality but at some point you run up against these being aluminum framed machines.

Also that being a PRS alpha there’s a chance that it has a Colombo spindle capable of higher than 18k rpm.

[Minuteman Graphics Fayetteville NC]

Fast Travel! I need to try that, I was thinking slower travel might be the trick, and am down to .5 in/per. Its better then what we were getting before I started, but not what I am used to.

Back to the shop I go!

Dave

[EricSchimel]

.5 IPS is waaaay to slow. Start at 3 to 4