back chamfering

[MoriMan]

Curious to how everyone goes about chamfering the bottom of a thru bore on a part. Say we have a 1" thick plate were opening up a laser cut hole to a finished diameter, then I want to chamfer the top and bottom of that bore. My current process is drawing 2 circles on the center of the bore, then changing the diameter of these circles and there z depths until it looks right in simulation. This is not hard, but its annoying fiddling with the arc diameters and z position several times until I get the correct chamfers I'm after. There has to be an easier way to do this I am hoping. 

[Jake L]

I don't do a lot of back chamfering, but I usually do out the math. Create the wire frame circles like you said, and use a 2D contour toolpath. I usually adjust the stock to leave to get what I'm looking for. This seems like a similar approach to what you're currently doing.

If I did back chamfering more often, I think I'd make up a calculator for it in excel. Input the tool dia, chamfer size, offset from shank, the chamfer angle if you want to do more than just 45 degrees, and have the calculator output an x and z shift to machine the chamfer. The calculator output would be input in the stock to leave page.

If there is an easier way to go about this I'd love to hear it, but this is the fastest way I know of.

[byte]

On 3/31/2023 at 4:44 PM, MoriMan said:

Curious to how everyone goes about chamfering the bottom of a thru bore on a part. Say we have a 1" thick plate were opening up a laser cut hole to a finished diameter, then I want to chamfer the top and bottom of that bore. My current process is drawing 2 circles on the center of the bore, then changing the diameter of these circles and there z depths until it looks right in simulation. This is not hard, but its annoying fiddling with the arc diameters and z position several times until I get the correct chamfers I'm after. There has to be an easier way to do this I am hoping. 

Surface finish contour is the preferred method for simple undercut machining

[Chally72]

Using deburr locked to 3 axis, and set to flank cutting, will generate back-chamfering paths in 2024 with dove-style tooling fairly painlessly. We do see the need for a dedicated back-spotting/back-chamfering holemaking toolpath that also supports flip-out style centrifugal/hydraulic/coolant driven tools for these scenarios.