High Speed Machining A286 - Who's tried it?

[neurosis]

Curious if anyone had attempted to high speed machine A286?

We're machining a slot (clevis part) that is about 1.8 deep and .625 wide.  Tool life in this garbage material is always a concern so I want to attempt a high speed approach. I don't see very much info around on this material.

 

[crazy^millman]

19 flute tool with a 3% step over. I have use 5 Flute to 12 Flute on it and kept the surface speed at the recommend call outs.

[neurosis]

I talked to Imco and they are recommending 250sfm but never gave a chip load or axial recommendation.

So far Ive been running at just over a 2% stepover and its cutting nice but the tool life isn't at good as I would hope.  I'm going to start looking for some cutters with more flutes. 

[Orvie]

I cut this stuff fairly often.

3% step over is as high as I would go with dynamic toolpaths.

130 SFM seems to be the sweet spot for roughing.

The tool will pull out of the holder with quality hydraulic chucks.

I use a Big Kaiser Mega Perfect holder to prevent tool pull out.

[crazy^millman]

Just now, Neurosis said:

I talked to Imco and they are recommending 250sfm but never gave a chip load or axial recommendation.

So far Ive been running at just over a 2% stepover and its cutting nice but the tool life isn't at good as I would hope.  I'm going to start looking for some cutters with more flutes. 

Increase your chip load per tooth to get a good cut verses a rubbing condition you might be getting. Might look to a 3/8 endmill to give some room to do the motion in dynamic toolpath.

Hydraulic Chucks are a key part to the process.

[neurosis]

A local distributor just happened to have some Imco 9flt .5 dia endmills on the shelf.  I'm going to order 2 of them and give it a shot.  Whats the worst that could happen. 

[crazy^millman]

43 minutes ago, Neurosis said:

A local distributor just happened to have some Imco 9flt .5 dia endmills on the shelf.  I'm going to order 2 of them and give it a shot.  Whats the worst that could happen. 

You will knock the project in the head. Don't be afraid of 200% or 300% DOC with that light of a step over. The core strength on a 9 flute is able to handle the DOC much better than say a 5 Flute would. Are you running 1000 PSI TSC with a Coolant Chiller? 

Ran some Ti not to long ago with 200% DOC and 5% ROC with .005 per tooth feed rate at 450 SFM getting about 300 minutes run time before tool needed to be changed.

[neurosis]

Unfortunately this machine doesn't have high pressure coolant.  I don't think that coolant will be a problem though.

We are used to running 5/8 dia Imco IPC 7flt  endmills in stainless 350% (close to 2.25) doc and 5% radial at 500sfm .005ipt. Were not afraid to run it fast and deep. LOL.  This material (A286) is proving to be a little more challenging where tool life in concerned. 

All good info.  Thanks!