Routing out square corners on 3 axis CNC

[dyun]

Hi,

I need some technical advice to better approach a method of routing a square (even though it cannot be perfectly square!) inside corners of an MDF door.
Recently I have tried to replicate a look of a mitred door with a 2-piece MDF (single frame with panel).
Now the problem is as you know, the corners cannot be perfectly square because of the spinning router bit.
I am trying to use a 1/8 radius bit to get it to look as close to 90 degrees as possible.

Now the inner part of the frame has a profile like all other nice looking doors do. However, with this profile it is extremely difficult to program tool path to route inner corners because profile is not sloped at an uniform angle.
I have seen other company do it with just a ball type bit with 3 axis CNC. We use a RouterSim on KOMO. It is a 3 axis CNC, plus we do not have the option of using an angled aggregate either.

Do you have a solution or any method to approach this problem in the most effective manner?

Thanks a lot!

Dominic.

[blackhawk]

Dominic,

When I do inside corners that need to be sharp, I use a 30 degree V bit and run a V carving toolpath for the corners. This will leave a perfect sharp corner at the top of the part. Then it is pretty easy to take a sharp chisel and clean the bottom.

[erniek]

Whiteside makes a bit that comes to a point and cuts a 3/16" radius. Part number is 1570. Use that a couple of times and then square the last bit out with a 1/8" endmill.