Initial cut depth

[tvannaman2000]

I've been using VC Desktop a little over a week and have noticed that my initial cut seems to be too deep in most cases, but all subsequent passes are fine.

When setting up the toolpath, I leave the Start Depth (D) to 0 and set my Cut Depth (C) to the desired depth. What i get is deep first cut of about 1/8 - 3/16" that really binds things down and has broken the wood free upon occasion. If it makes it past that first pass, all subsequent passes are much shallower and complete with no problems. Slowing down the cut rate helps marginally and I've tried to adjust in the tool section, but can't figure out how to control that initial cut. Does leaving it at 0 cause it to default to something else? Should I put something in there like .06" ?

I'd really like to find something where I don't have to manually adjust the passes every single time I configure a toolpath. I've had no such problems when doing engraving toolpaths.

Thanks,

Tim.

[Adrian]

What type of toolpath is it? The depth of each pass is defined by the pass depth set for the tool in the database but can be overridden by clicking the Edit Passes button if you have Advanced toolpath options turned on.

How are you setting the Z Zero? It sounds to me like the zero is off on the machine so the first pass is that amount off plus the actual pass depth.

[tvannaman2000]

It's a profile toolpath. I'm using UGS to execute the toolpaths. I lower the bit down to the wood until the piece of paper I have under it starts to catch, I then reset all my axis's. I basically use the same method with other other software and I have no problems there so I'm pretty sure it's ok. All the final depths are correct, so I would think if I were zeroing out Z axis improperly, it would show up in the final depth of cut.

I will play with the tool setting more and check out the pass depth in Advanced options.

Thanks.

[martin54]

How flat is your stock material ? The only way that the first pass would be greater than the remaining passes would be if your z zero were set to low or you had manually set each pass depth using the advanced settings.
Your paper method of setting z zero should be fine but if your stock isn't flat & you use a low spot to set it then you would get a deeper first pass although I wouldn't have thought it would cause the sort of problem you say you are seeing