Submitted by drummerene t3_xvnqbk in DIY
I have titanium nitride coated cobalt drill bits. These are the kind I have https://www.amazon.com/Milwaukee-48-89-2331-Piece-Cobalt-HELIX/dp/B07SQFS9RQ/ref=cm_cr_arp_d_product_top?ie=UTF8
Or can I use 3 in 1 fast acting penetrant or what about petroleum jelly? Does it have to be something like a 3 in 1 multi purpose oil or motor oil? I will be using a 1/4" bit. Do I need oil at all to preserve these bits and if so how much longer would they last?
ZeroTrousers3D t1_ir2wxx5 wrote
Step 1: Mark your holes
Step 2: use a center punch or an automatic punch on your marks
Now you're ready to drill. Any time you're drilling small metal bits use a vise or a pair of pliers, not your fingers.
You're going to use the drill at a low speed with moderate pressure. You can get away without using lubricant for small holes on thin & soft metals, but for anything hardened or anything thick you want to use a cutting oil. Even repeated drilling of thin stock can prematurely dull bits
3-1 oil will work in a pinch, but it's not the best oil for the job. If you're allergic to buying cutting oil, 10w30 motor oil works well and automatic transmission fluid is magical stuff.
Once you're done, clean your (oily) parts with varsol or mineral spirits, dry with a rag and re-oil the hinge. Make sure to dispose of your rags safely.
Both sides of the lube/no lube argument has merit for a one time small job. That said, is still have a set of HSS bits that are pretty decent because I use ATF when I use them on steel. Paper towels are way cheaper than bits