Trying to upgrade my leaf spring centering pins from 5/16 to 3/8. Problem is, I can't get the hole in the springs reamed out. I've tried a 3/8 titanium bit and a hand drill but that ain't cuttin it. What's it gonna take?

About 3 Titanium bits and a drill press lots of lube and a few cases of beer.:flipoff2: GOOD LUCK!

I tried this, pressed too hard and burned the bit. Also hardened the metal, had to use a die grinder with a $30 bit.

However, the next four went better. Used 5 bits, just go very slow and use lots of lube. I used a tall can of WD40 for every spring. Good Luck

I seem to remember someone saying "use Masonary bits w/lube" something about cutting through like butter.

Give it a try..... :)

man I must have crappy springs cause when I redrilled mine it was like butta..

Originally posted by Mr.N
I tried this, pressed too hard and burned the bit. Also hardened the metal, had to use a die grinder with a $30 bit.

However, the next four went better. Used 5 bits, just go very slow and use lots of lube. I used a tall can of WD40 for every spring. Good Luck

Why would you use WD40 as lube? Gear oil works much better. Or get some machine grade lube.

Get some high quality bits and use a drill press. Off hand i dont knwo what rpm you sould run but there should be a chart on press somewhere.

Or bring them to a machine shop. Shouldnt take to long or be that much.

3/8" round mill bastard file with the handle cut off and stuck in a hand drill on reverse (so it doesn't get stuck) took about 10 seconds to ream out. There ya have it for the arcives.