Help with long reach in aluminum

[Rstewart]

Attached is a picture of the part I'm cutting, 7050 T7 Alum. Everything is cutting well, except I'd like a way to put a slight taper on the green wall so my 2" facemill won't rub all the way down (about 4").

 

If it was just a straight wall I'd create a drafted surface, but how would I accomplish this along that 45 Deg "arm" in blue? I want to leave anywhere from .03" to .06" for finishing the 45 Deg piece.

 

All the material around the arm is just waste, yes I could take the HEAVY part outta the machine and band saw it off but I'm kinda lazy.

[djstedman]

Why not create a 2D contour that follows the contour of that green wall and uses draft angle to provide relief? Seems like the wall in blue should have relief already just from its geometry but if you wanted you could even do that with a 2D contour with a draft angle and using stock to leave.

[alloutmx]

can you relieve beind the face mill?

[MotorCityMinion]

If your only roughing that one side in a separate op, then djstedman had the answer. Taper wall in 2D contour. If you want to rough the entire perimeter of the part in one op, create an extruded surface that mimics the wall profile with a draft and include that in your drive surfaces.

[Rstewart]

Yeah I am contouring the whole front side (green & blue arm). Don't think I can 2D taper wall cause the green wall would taper like 2Deg but the blue is 45Deg. Sorry If I'm not seeing the solution

 

Guess Some extruded surfs are gonna be needed, kinda what I was thinkin.

[Jayson Kramer]

Rstewart can you share the file with any of us to help you? The 2d contour will work I have done that before.

 

if you are surfacing then the option of creating a draft surface works well.

[djstedman]

I just meant make it two operations.. first one does green wall with 2d contour to full depth with a taper of like 1 or 2 degrees..

That leaves the center blue area uncut..

 

Then make a second op to do the blue section just path a straight line at the bottom of the blue angle with a different taper of whatever angle it finishes at and leave .03 or .05 or whatever you wanted leave..

 

I cant see how its going to make a lot of difference if you do it in on operation or two.. that size part with a facemill your not talking a lot of time for a facemill unless your trying to get really small scallops or something.. its aluminum though .. so even with fairly large scallops throw a 1/2 ball mill at it in a long holder to clean up the heavy scallops before finish..

[Rstewart]

Jay, Thanks for the offer! Djstedman: I had a brain fart for a while, but now I understand the 2D with different ops. I have no problems splitting it into different ops.

 

Thanks for the quick replies guys

 

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