how to mill inside an area and not over an area?

[jedioliver]

Hi guys,

I would like to know if there is a way to mill inside a delimited area?

When I choose a polyline that delimits the area I would like to mill, the tool always run over this polyline, at the beginning or the end of the toolpath depending on the offset option I choose (outside to inside or inside to outside).

But I would like the tool to mill only to the tangency of this polyline, and not over this polyline.
Is there a way to do so?

Thanks.

Jedioliver

[ger21]

Use cutter comp. G41 (climb cut) or G42. Not sure how to do it with VM, though.

[jedioliver]

Thanks for your answer Gerry.

Perhaps there is a way to do so using the post processor editor, but I don't know how?

Any idea guys?

Thanks once again.

Jedioliver

[DareBee]

I believe this was discussed at Mecsoft forum.

[pa0akv]

I have the same problem.
Is there a possibility to compensate the cutter diameter?

Thanks Andre

[jedioliver]

The only solution I have find is to offset the curve by half the diameter of the tool I use.
When it's not possible to offset the curve, I use 2 1/2 Pocketing or 3D Pocketing or 3D curve machining. You have with the last one the option "on " or along the curve.

Then I use the "move" function for the toolpath to duplicate the toolpath on z axis.

Hope this help.

Olivier

[DareBee]

As far as I know, in the current VM, A region used as toolpath limiting boundary (not a cutting toolpath) limits the toolpath ONLY not the cutter.
This is a much desired enhancement IMO.
Meaning that it does not allow for cutter compensation.
Using an offset to downsize the region as jedi states is the way that I do it.
However, the simplest and fastest cutting of the above profile is best accomplished using 2.5D machining methods anyway.

[jedioliver]

Yeah...hope the new version will offer "on - inside - outside" cutting area option on all milling operations...

[Unabiker]

Originally Posted by jedioliver Hi guys, I would like to know if there is a way to mill inside a delimited area? When I choose a polyline that delimits the area I would like to mill, the tool always run over this polyline, at the beginning or the end of the toolpath depending on the offset option I choose (outside to inside or inside to outside). But I would like the tool to mill only to the tangency of this polyline, and not over this polyline. Is there a way to do so? Thanks. Jedioliver

To do this operation in Visual Mill (I'm using v5.0):
-select your polyline. It needs to be a closed polyline for it to work.
-asuming you have already selected your tool and feed rates, click "2 1/2 Axis Milling"
-select "Engraving"
-in the popup window, you'll have the option to select "On condition" or "To condition." Select "To Condition," then chose whether you want to cut inside or outside your polyline
-set your cut depth parameters
-check the Entry/Exit settings. Make sure the Exit angle is set to 0 to prevent trashing parts, tools and vises.
-generate your toolpath
-cut parts, bask in glory

[jedioliver]

Thanks Unabiker for your help.

It's true I have found some good solutions to my problems using 2 1/2 functions of VM5.

Jedi

[Michael M]

Originally Posted by jedioliver When I choose a polyline that delimits the area I would like to mill, the tool always run over this polyline, at the beginning or the end of the toolpath depending on the offset option I choose (outside to inside or inside to outside).

That sounds like a problem I was having. What you may need to do is tweak the entry/exit parameters for the cut. VM would do everything fine and then slice off at the very end making a nicely radiused gouge.

You can change the direction and length of the exit/retract motions, and sometimes moving the start/stop point of the curve to a different location can help avoid running into another part of the curve (or an adjacent feature.

I don't know why it needs to have a 1/4" or so exit motion - once you've gotten a few thou in X or Y off the wall you are cutting you may as well retract the spindle vertically out of the part.

Moving the start/stop points of different curves can help make for smoother transitions between features.

cheers,
Michael