Doofus Award

[Thomas Dean]

Thanks! I never think of that...really computer savy here.

[Dodge]

I know folks will argue against this but I have been using motor oil, transmission fluid, even wd40 when drilling, for years. (I have Dexron ATF in the pump can currently) At least don't drill metal, dry. 1/4" thru sheet metal, etc, is an exception and I'm sure theres a formula to support this, but the point is, you need a lube or coolant or both. Flood is best, "cutting" oil is desirable, but engine oil is better than nothing at all IMHO. Most important, however, is correct RPM for the drill bit being used. Google it. I have the fortune of finding a drill/tap reference manual from the Cleavland Drill co. and I keep it near my drill bits. Find and print a chart and keep it with/near your drill press and you will be a happier camper

[brucegodlesky]

Good advice Dodge. I've ruint more bits by running too fast or chipping them out going too slow with no lubricant.
I been using water soluble oil as lubricant/coolant. Really does the job with softer stuff like brass and nickelsilver.

[MRobb]

Thanks to all for the great advice. And thanks habu68 for the link on "Modern Blacksmithing, Rational Horse". Can't wait to read it.

[fat pete]

feeds and speeds are important....especially cause of all the different alloys....coolants for different applications is important too

[Pault17]

Pete, thanks for the links.
all, thanks for not beating me to death. I do help my drill speed cranked way down.
I have just finished drilling several 1/2 md holes in 1/2 inch and one inch steel with little clatter and no burnt bits

[John N]

I drill a lot without any coolant of any type, no problems (up to 3" dia) . on the radial arm drills we have a squeezy bottle with some soluable coolant in that we squirt at the bit every now and then to cool it off a touch.

With correct chuck speeds, and a good solid steady feed pressure you can drill all day without coolant.

I do like a proper cutting oil / grease when tapping holes though. 1 broken tap in an important job will cost more than a lifetimes supply of lube!

[larrynjr]

A problem that I ran into while making a bunch of wall hooks, I got a good heat on them after they were formed then water quenched them to help get the scale to come off. Not realizing that cooling them that quickly also makes them very hard, I ruined quite a few drill bits try to drill holes through the top of those hooks before I figured it out and reheated them and let them cool slowly. After that they drilled easily. There was a very high pitched squealing noise when try to drill those hardened hooks!

[ThomasPowers]

Yup A-36 is *not* necessarily mild steel a lot of tricks that worked with wrought iron or real mild steel will get you into trouble with A-36!

[primtechsmith]

Larry.
What I tend to do with my wall hooks and S hooks is use the heat to your advantage to descale the material. Light finishing hammer blows at a gray heat will knock off a lot of the scale and having a hand wire brush handy to run over it a few times helps too. Then I just throw them all on the floor and let them cool on their own.

I did the "quench before drilling" once. Mike came over and told me that noise was not good...and why. The why is always important! The next day he bought a Drill Doctor to sharpen the drill bits and a new lesson was formed....reading calipers to correctly put all the drill bits back in their proper places after sharpening them.

Like Mike tells me: "Experience is a wonderful thing."
:-)

Peyton