Re: How much rigidity do I need
You might give us a little bit more to look at.
Steel is quite hard to cut for a light mill. Large bits will generate much larger forces so will flex the mill a lot. Smaller bit will cut better but break easy if the mill flexes, which it will.
So what kind of steel do you plan on cutting? Is that the main use? If so the mill needs to be 3 or 4 times stronger.
If you only want to do 1/8" steel plate rarely then a 1/4" cutter might be OK and 5" box section frame sand or cement filled might be OK.
Your Z it too tall right now unless you have to have it that way.
Dave
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