So the Doc...

[oldretread]

So the Doc flops two impressions and a box of Buffalo .150 thermoform soft splint/brux acrylic on the bench and says make me a couple of night guards.
No big deal I think. Never used the stuff, but how difficult can it be?
First try a failure. Directions say "let material slump slightly. Other thermo form materials I have been using, 1 in. was about right. Gave it 1/2 inch. (slight) OOOPs... not good. Second try, 1 in. O.K...
Slip it off to cut/trim...Cuts like shiet with a BP and a new #25 blade. Out come the chicken boneing shears. Get the job done. Fingers hurt, wrist hurts...Remember I'm 70... There has to be a better way I'm thinking, so go ask...
Final trimming with white stone and flame polishing works fine...
Need advice on cutting to basic shape/form... Hobby hot knife?

 

[labdude]

Check out the videos here....
Glidewell Laboratories || Laboratory || Thermoforming

 

[TheLabGuy]

I always use a fine cutting disk and my handpiece.....

 

[CloudPeakDL]

Buffalo makes a hot knife that works well. But a fiber disk in your lathe works well if you don't have a cutting disk for your hand piece.

 

[bdg]

I bought a hot knife for cutting out the TAP III appliances.
But I think it is a real pain
I ended up using a diamond disc and handpiece

Its flexible, and w/ adjusting the speed you find the range to cut w/out melting it back together

Makes FAST work of the job.

This is the disc that I use:

 

[oldretread]

Again my thanks for all the advice folks. Have both fibre and abrasive disks for the handpiece. Will try again at a slower speed.
Labdude, that is some nice toy. Since The Doc does so few of these, I think I will just remount the model and flame the occlusal and close. Playing with the material I found it flames to softness quite nicely to further adapt the material selectively into undercuts. Should work on the occlusal as well. Time to play with the material and see.
Thanks again all.

 

[oldretread]

Disc in a handpiece is the answer. I did the unthinkable. I made an assumption...that a disc would gum up immediately. Thanks for helping the brain dead, folks.

 

[labdude]

I know those Gldewell goodies are expensive, but, those videos, they have tid bits of info on the finishing of things. Can be very helpful.

 

[JohnWilson]

Sharp pair of scissors work great for us for the soft EVA materials. We use typical fastcut white wheel and a torch for final smoothing.

I have been doing it this way for 20 years and I am too damn stubborn to change.