Bumps on profile cuts

[Brady Watson]

I didn't tighten the step motors yet. I may still do that if I run into problems down the road. For now, I'm a little worried about overtightening them.

The first cut I tried was perfect... until the part broke loose because the material thickness was off and I cut all the way through the material.

If you are running a PRS - it is impossible to overtighten them. On a PRT the correct tension is 3.5 turns on the buckle just as the spring starts to get some tension on it.

Also, flatness of your spoilboard is paramount. It will haunt you forever and mess up jobs etc if it is not glued down to the plywood support board - with zero screws in the lamination. It should be machined flat with a large diameter bit so that table is true to the tool. This will remedy the 'cutting deeper here and shallow over there' condition. - Provided that the parts are being held down correctly.

Flatness is very important. A few cutter kerf tracks here & there isn't.

-B

[asteude]

Brady - could you explain why you say you can't overtighten the motors on the PRS? I imagine you could cause undue stresses and wear on the motors if the gears are engaged too tightly.

My spoilboard is in dire need of being replaced, but it is glued and flat where it's not shredded by innumerable screw ups.

Andy

[bleeth]

Brady: there is a good point there. You can put quite a bit of pressure from the motors pinions to the rack on a PRS and have no problem but I wouldn't suggest doing something like pulling them up with a clamp tightened heavily as the engagement could then be so tight that you would blow a driver trying to move.