Originally Posted By ENGCPT:
I'm going to try my hand on some 80% lowers tonight. Is WD40 a decent cutting fluid or do I need something else?
If its no good, what do you recommend I can get at homedepot/lowes/menards?
Thanks
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When you're cutting holes with bits, take the sharpness out of the tip by lightly filing 90° perpendicular to the cutting edge because this will keep your bit from grabbing the aluminum and not torque on the piece. Your goal is to take the sharpness down rather than ruining it's ability to cut.
There's information on Google if you search things like: "how to drill brass(not aluminum)" as this is a trick brass cutters use and it applies to aluminum very well.
Also, ruin the bit's cutting surface where it doesn't matter or else you run the risk of cutting your jig's inserts, which will cause non-centered holes.
When drilling aluminum, use moderate to heavy pressure and slower speed. Be on the lowest speed setting and throttle the trigger until you find the best low speed. You should get aluminum coils instead of shavings if you're drilling correctly.
Moderate to heavy pressure and low speed.
Don't be in a hurry to mill. Take more passes w/ less depth instead of fewer passes with more depth.
Use a face shield, or eye pro at minimum.
Use a disposable rain coat so chips don't stick to your clothes.
Have a vacuum nearby.
Don't expect this to take just one day.
Go slow and have fun with it.
If your safety detent isn't reaching in enough, take a drill bit by hand and clear any chips/burrs from it's channel. Sometimes, you may have to drill that hole slightly deeper. Be careful, the hole uses two sizes, as I recall. O could be wrong here but think I am right.