Extended reach 1/8" flat mill feeds and speeds

Anyone have some extended reach 1/8" endmills? I’m trying to figure out a good feed and speed setting to start with in white pine. What DOC, feeds and speeds do you run it at? G-wizard gives me deflection warnings no matter what I try. Specs:

Diameter: .125"
Flute length: 1"
Tool stickout: a little over 2" at most

I don’t want to break this sucker on the first time out of the gate, so even taken small DOC at about .05", G-wizard says I’ve got it wrong. Deflection is the main thing I’m worried about; I will adjust feeds and speeds for good chip removal and tool life once I’m confident I won’t break it. Even with the turtle slider all the way to 1%, It warns me about .000247 deflection. How much deflection do I really need to be concerned with?

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Depending on your flute length, I run 1/8" 1" flute length at 70 IPM, .05" DOC.

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Thanks. I have 1" flute length as well, and was planning on about .05" DOC. I was planning on starting out at about 30-40 IPM for Feed. So I think I’m on track for that being a conservative estimate, which is how I want to start out.

Conservative is good when getting familiar with your machine.

I’m dealing with deflection of 1/8" bits in another thread here with .1" DOC, so I’d stay well under that, which it already sounds like you are. Even at much slower travel speeds .1 seems too much.

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Thanks again for the help folks. Due to my stock size, and some other features on my current project, I needed that 1/8" extended reach to work without issue. I ran the bit at .05" DOC at around 31 IPM worked great when doing these contours where you are cutting with 100% of the bit diameter.

New project will hopefully be done over the weekend, Plus some spares for friends.

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