Surface Rough parallel

[Torr Man]

Hi Guys

 

I have a casting that has a surface. I am using the above command to machine the surface. If the casting has 5mm of meat all over, What command do I use to allow the tool to follow the shape of the suface and remove the 5mm

[timhochs]

If I understand the scenario correctly that you have 5mm of stock remaining after roughing, I would use surface finish parallel.

[Jim at Gentex]

I would also use surface > finish > parallel.

 

You can use the 'stock to leave' feature to take off most of the 5mm with one or two passes, then take a finish pass of maybe .5 mm or whatever amount you like.

 

The surface > rough > parallel is better suited for machining from a solid block rather than a casting. If you use it on a casting that is close to nominal, the resulting program will cut quite a bit of air above the part.

[3R!< W3NG3R]

Parallel is ok if there are no steep walls.

 

Blend would probably give you a better finish and can do walls nicely.

[Torr Man]

Thanks Guys that is perfect just what I want, But how do I control the amount that I take off in each pass ie: 5mm of stock to come off in two passes of 2.5mm for each pass.

[Quickmike]

Make one pass leaving amount "x". Than make another pass leaving the desired amount for a finish pass at 0. You might be able to cut your time down during the roughing by taking a larger stepover and loosening up the tolerances a little. What type of material are you cutting?

[Jim at Gentex]

quote:

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But how do I control the amount that I take off in each pass ie: 5mm of stock to come off in two passes of 2.5mm for each pass.

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If you want to take it all in 2 passes, you will use 2 toolpaths. The only difference will be the 'Stock to leave on drive' box on the Surface Parameters page. For the first pass, enter 2.5 stock to leave. Copy and paste the operation, then change the stock to leave to 0 for the second operation. Post both operations together into one nc file and there you have it. The first pass will cut at +2.5, and the second pass will cut at zero.

 

I would ALMOST ALWAYS take a finish pass, depending on what kind of surface finish you are looking for. As Quickmike said, you can take the initial passes with a larger stepover value, then tighten it up for the last pass to get the best surface finish.

 

If that is the case, simply use 3 operations instead of 2. The first pass stock to leave could be 2.5mm, the second pass at .5mm stock to leave, and the third at 0 stock to leave with a smaller stepover. Again, post all 3 operations together and you will have a program that cuts the first pass at +2.5, the second pass at +.5, and the third pass at zero with a smaller stepover for a better finish. That is how I would most likely do it.