Thread: CNC Tooling
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Unread 20-06-2013, 00:47
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Re: CNC Tooling

We use a mister too. I'm not sure of the model. It does help a significant amount, we've been able to cut faster after starting using it (I think we started out at like 2 in/min with a 1/4" cutter in 1/4" alu before, now we set it to 6 ipm fairly regularly). In my experience, mist coolant helps most with cutters in the 1/4" to 1/2" range, where heating tends to slow down your cutting speed. With very small cutters (1/8" or smaller) I've seen them break more because of their small diameter than whether or not coolant was used.

Like others have said, collection or recycling isn't really an issue as the mister doesn't put out much fluid. However, it's very important to clean up properly after using the coolant. A lot of our steel tool holders have noticeable rusting in small spots from the mist, and after some pooled under our vise, it left a mark on the machine's table. I recommend wiping down the machine well every day, and taking up any fixtures on the table every week or so. On the other hand, it's a good idea to do this anyways.

8000 is extremely fast for tools in the 1/4" or 1/2" range, in my experience. With coolant, I believe we typically set 1/4" two flute cutters at 2000 rpm or so in 1/4" aluminium at a feed rate of about 5 ipm. Our mill only goes to 3600 rpm, and we only really use it that high for very small tooling.
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