Surface Rough Contour ?

[Rob B]

I am programing a solid using Surface Rough Contour toolpath. Everything is correct except the first depth cut that my tool makes. It is cutting .100 deep on first cut, then it moves to the amount that I have indicated in my parameters page. I don't want to take anymore than .025-.030 depth of cut. This is the case except for the very first cut across the part. After the first cut my depth are held under .030 per pass.

What might be causing this first cut to go so much deeper than the rest.

 

Thanks

Rob

[Storkman]

Have you tried adjusting the cut depths? Adjustment to top cut? I never use this toolpath, so I'm not sure.

[gavetta]

I use surface rough pocket alot and have to adjust the top cut by a negative value to get the first cut to be closer to the top of stock if the surfaces are not close to the top i.e.

Surface is .5 below top of stock

adjust top cut -.4 will get you some where near .1 below top of stock but you also have to factor in any stock to leave etc.

It's really a little weird but if you play around with it you should be able to get what you need. Hope this helps.

Al

[Storkman]

You could set the cut depths to absolute then go select the top of the stock and somewhere below the surface (won't go beyond the surface anyways) for the max depth.

[Matt Berube at Ferron Mold]

I usually use absolute cut depths. That takes out any confusion for me... Set minimum cut depth to what you want for first pass(-.025). Set maximum depth to whatever you need. First cut will be Z-.025 and the rest will be less than/equal to your step-downs specified in toolpath parameters.

[Lee.]

I got in late obn this one.

 

Like most said use Absolute Depth Cuts.

 

It's self explanatory.

[Rob B]

Seems what the problem is "after taking a closer look". Mastercam doesn't realize there is stock that hasn't been removed. The toolpath is taking the ball mill to the postion that it is tangent or making contact with the endmill. It is more or less creating a toolpath similar to finish contour.

 

I have put the drawing on the ftp site. It is located in the Solids folder, file name is ROB.MC9

 

Oper7 in the Operrations Manger is the toolpath that I have been having the trouble with.

 

If you do a backplot you will see how i am trying to cut this part. You will see that I have cut a straight shoulder to start with. I then want to rough the angled surface (oper7), then do a finish cut.

Hope you can understand or see what I am trying to get done to this part.

 

Thanks

Rob

[Rob B]

I changed to rough flowline and got what I needed.

Thanks for the help.

I now understand how the cut depth works.

 

Thanks

Rob