I would power it separately as it is useful to turn on and off whilst cutting or after cutting to clear swarf. You can also put a ventory to put a coolant or oil in the air quite easily controler by a hand controle valve.

David

So give us a link to the 'cheap air blast unit', re-cutting chips is a serious cause of poor surface finish in my opinion

Ah shame, thought this was a link for a cheap vortex tube cooling unit.

Re using a misting device, I would be worried about breathing in finely atomised cutting fluid.

My Bijur Spraymist units are independently switched on the lathes whilst the one on the Bridgeport is linked to the motor circuit.

Bridgeport motor direction switch has a central motor off position so the air blast / lube can be run without the spindle turning. Handy for extra clearing and much safer during set up. Probably the best way overall even though if means an extra switch to select between run with spindle and run independent modes.

Especially so if you are using lubrication because it needs to be directed fairly precisely at where the tool meets the work. The whole idea of such systems being to use the minimum amount of lubricant put exactly where its wanted rather than spraying all over the place so adjustment may take bit of time. Having the spindle running whilst you get things just so is potentially somewhat unsafe.

Ideal would probably be another solenoid, rather than a simple valve on the lubricant, too but thats getting complicated.

The inexpensive import Locline replicas don't have the best of reputations for joint sealing. There is reason why the real thing is expensive. I'd not expect it to be air tight and would run a concentric flexi tubes up the middle, outer one for air, under one for lube so the "cheap-loc" line just gives you a bendy but stiff tube for adjustment purposes. That was what I planned to do when looking into using the inexpensive offerings as an alternative to DIY but I was lucky enough to find Spraymist units at affordable prices. About two or three times upper end of new cheap units. Hafta say I'm not incredibly impressed by them but they can be got to work OK (ish). At full price (never gonna happen) it would have been seriously angry sabre toothed bunny (extremely large breed) time.

Clive

Edited By Clive Foster on 13/07/2019 10:16:55