Max Milling Depth
Max Milling Depth
(OP)
Wondering if there is a general rule of thumb for max milling depth? I'm designing a fiber optics cover that is about 4" inches tall. Due to design requirements it's going to be machined aluminum. I'm debating on whether it should be designed in 2 pieces, each 2" tall and assembled, or 1 piece. If milling aluminum at a 4" depth does not require a special process or extra cost I would rather do that.
Thanks,
Sean





RE: Max Milling Depth
RE: Max Milling Depth
You're OK with him buying a 4 inch deep casting and then machining out a 3-7/8 deep hole in the middle to get a 1/8 thick wall?
It might not be right - but that doesn't seem like the right process optimizer.
RE: Max Milling Depth
Processes like Rubber Plaster Molding can be competitive with machining at fairly low volumes. On a part I recently did I seem to recall the break even between cast & machined was somewhere below 30 parts.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Max Milling Depth
For extra deep pockets, plunge milling can be effective for roughing. I.e., move the milling cutter to a fixed XY position, and drive it in the Z direction to nearly full depth. That way, the cutter is stressed in compression, not bending. Then relocate the cutter and plunge again, and repeat.
Some mills have plunge cycles built in.
Mike Halloran
Pembroke Pines, FL, USA
RE: Max Milling Depth
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Max Milling Depth
I understand there will be several passes, I was just wondering, because how thin the wall needs be with fairly tight tolerances, if there could potentially be any wobble with an extended shank. I'm guessing that a standard shank is shorter than 4" (I could be wrong).
Thanks,
Sean
RE: Max Milling Depth
If the quantity is high enough, have a die made for your shape and have the part extruded.
"Wildfires are dangerous, hard to control, and economically catastrophic."
Ben Loosli
RE: Max Milling Depth
Thanks,
Sean
RE: Max Milling Depth
A number of years back I machined a number of complex camera mount systems for aerial survey services. I fully understand the need for preciseness in the fit-up of all components. Gasketed housings work well when used with lips or bosses that retain your absolute geometry while providing the correct amount of compression allowance for the gaskets or o-rings.
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Max Milling Depth
We do use wire EDM a lot here to handle athermal flexure requirements, however I not know of anything done here with 'sinker EDM'. I just did a little research on that process, and though it's fascinating, it is a high cost solution. I have modeled 2 concepts, one being a mono part and the other being a 2 piece (base and top) that I would have vacuum brazed. That being said for the 2 piece design, wouldn't milling 2" deep parts sort of get me to the same place as sinker EDMing a base and a top?
Thanks,
Sean
RE: Max Milling Depth
Yes, it would. It comes down to a matter of what processes are readily available to you.
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Max Milling Depth
You've been really helpful. I appreciate your time...
Thanks,
Sean