Cutting Pockets

[sheldon@dingwallguitars.com]

I don't know where to look for this problem. I am trying to cut two rectangular pockets. When I create the tool paths using Vector, the pockets are oversized by almost 10%. When I try to cut the pockets manually using the CR command, the pockets are undersized by around 3%. I've triple checked the calibration values. The machine is tight.

I'm doing everything in metric, but I can't see there being a problem with that.

[david allen]

did you double check that the bit size is set correctly?

(speaking from experience)

[sheldon@dingwallguitars.com]

I set the bit diameter to 6.35 mm. Actual measured cutting diameter was 6.19, not enough difference to account for the over and undersized results.

[sheldon@dingwallguitars.com]

I'm getting better results now and I thought I'd pass on what I've learned.

Bit deflection and a slightly undersized cutter (I should have known better to measure exact size)accounted for the undersized pockets using the CR commands. Thanks to Dave at Shopbot for leading me in that direction.

The cause of the oversize pockets using Vector generated files was due to the way Vector handles tool compensation on the finish pass - it doesn't - you have to manually add the tool radius to the finish distance. Otherwise it centers the cut on the line. Thanks to Fred Smith for pointing that out.

[Rick]

Wow

[jkforney]

Sheldon
As you found out, Vector will not put in a compensation for the final cut in the pocket routine. As a matter of course, I always put the radius (1/2 of your cutter size)in the final distance box after checking final distance. This is required since machines using g code can self compensate for the cutter and shopbot can't (I think this is the explanation I received, but in any case we shopbotters need to do it)

In Vector nine there are two other pocket choices. Neither makes a final pass so this is not a issue. Actually they do some really neat stuff.

Also. I have seen the new 350 page plus manual. Start bugging shopbot to get a copy. Everything is in one place with many illustrations and step by step instructions. I don't think it is going to be free (as a matter of fact, I'm pretty sure) but what an aid. I know that they (shopbot) will love me for having people call them. They have so much free time, but this is great.

John Forney

[Nancy]

The new manual for Vector is still in publication and will not be available to us at ShopBot until after the first of June at the earliest according to ImService. We have not received a copy.