Undercutting with a slot mill

[HMI1953]

We currently are working on a part that has a 25 degree undercut bevel. We are trying to use a slot mill with corner radius to cut from the top down using the top edge of the cutter. The only way we can make it work is to lie to the computer and tell it that the cutter has a full radius, and when we send it to the machine have the z-height of the tool set the difference deeper. Is there an another way to cut with the top edge, and if so how? the tool path we are using is a 2d- swept

[DAN 1313]

Can you use a dovetail type mill Harvey tool carries a off the self standard sizes and can make custom sizes. I use them alot.

[HMI1953]

the dovetail cutter is not an option due to the overall length of the part,

[DAN 1313]

Surface finish contour will also work.

[RonC.]

Create custom tool geometry?

[Jayson Kramer]

you want to use surface contour or Flowline to do this can you share the file for better view?

[HMI1953]

we tried flowline and it only cut with the bottom of the cutter and not the top

[Rstewart]

Create custom tool geometry?

 

Yup, SF Contour. Create custom tool. I've cut an inside elliptical rad with a lollipop using the "top" of the tool

[baldhead]

Can you change the z height in the 2d swept wireframe across contour geometry rather than z height in machine?

[Jayson Kramer]

I am getting ready to do some of this in the next few hours on the part I am working on. Can you share you file and give me the size of the tool data.

[baldhead]

Is this what you're trying to do?

[Guest]

You'll need to turn off the gouge checking too in order to get it to go under.

[Jayson Kramer]

Ok I see you want to this profile and the only paths that will look at the radii are the ones when you use surfacing technics.

[Oscar R.]

Or something like this?

 

[Brian Pallas]

You could use swept 2d, program the angle as you are using the bottom of a tool, and then transform mirror the toolpath. I've done it before with a button cutter and it worked.

[JoshC]

If you happen to have the multiaxis package, those toolpaths will allow for the most toolpath control and are always my first choice on undercuts if you have them, simply choose a path and tell it 3 axis. if you do not have those paths then flowline like others have stated typically works very well also.

[HMI1953]

Or something like this?

 

 

this is what we are doing except it was a 3/r ring with a bump out on it, turning of the gouge check seemed to work, but the 2d swept came out a lot nicer.

[Jayson Kramer]

When comes to under cut with surfaces some time you have to rebuild the surface to make it work right. once again 2d swept will work to a point but does not support looking at the top and bottom of the tool. Just like 3d contour to not compensate for the tangency of the radii of the tool like when surfacing.