Milling an edge with a face mill

[zimm0who0net]

Hi. I've got a 2" face mill with 3 90 degree cutters in it. My setup is a Bridgeport with a 2D cnc. It involves facing a 1.25" x 3" piece of aluminum and then milling about 0.300" down on the edge. (see image)

So, my question. Can I finish facing, drop the Z and then run the edge with the face mill or do I have to switch to an end mill? Obviously using the face mill will significantly increase my cycle time on this one because it's a pain to manually change tools, reset my Z position, etc, but I don't know if I'm going to have massive problems trying to mill an edge with a face mill.

 

[Alexander McGilton]

If your face mill is equivalent this one, I don't see a problem. You haven't specified what make or model of face mill you have or its inserts, so I can't make a better assessment. Note that the below has a .5 inch depth of cut limit.

Shell Mill - Face Mill 90 Deg X 2.0 dia X Rectangle MariTool

www.maritool.com

 

[mmcmdl]

increase

Didn't you mean decrease ? Why not just use an end mill and profile the entire thing ?

 

[zimm0who0net]

It's a cheapo Shars with TPG43 inserts (the triangles). Here's the actual inserts used.

Didn't you mean decrease ? Why not just use an end mill and profile the entire thing ?

(yes... decrease! oops)
I could do it all with an end mill but it will take 3 or 4 passes with a HSS end mill and my feed rates will be significantly slower, but it's better than changing tools for sure. (plus I'm looking for an excuse to use my new face mill, but I don't want to do something stupid)

 

[mmcmdl]

(yes... decrease!)
I could do it all with an end mill but it will take 3 or 4 passes with a HSS end mill and my feed rates will be significantly slower, but it's better than changing tools for sure.

It's a 2 minute cycle time at max . A 1" 2 flute at 15 ipm or so feed . 2 passes across the top , drop down and climb mill the profile . No tool changes required .

 

[MrWhoopee]

If the mill is designed to cut to a square shoulder, then I see no problem. Those TPG inserts are old school, but they will certainly do the job.

 

[zimm0who0net]

Well, it worked. It got a bit chattery on the edges though (scared me a bit). Finish still looks fine, but I didn't like the noise. I think I'll go back to doing this with the end mill like mmcmdl suggested.

 

[Alexander McGilton]

Indexable endmills and face mills are often a compromise from ground end mills and shell mills. The are very economical compared to their solid carbide counter parts, as they can be quickly indexed to a new sharp edge. And often do so cheaper than replacing a larger carbide cutter. Though the concentricity of the indexing often is compromised compared to solid tooling. The fluets at times have an inconsistent chip load. Leading the chatter or rough finish. They also don't always permit as many flutes as another cutters may.