Need help with a core drill - Contractor Talk - Professional Construction and Remodeling Forum

FJRFencer · 04-16-2009, 09:19 PM

I have a milwaukee 20 amp on a stand. My 4 inch bit just refuses to come off. I have let the thing soak for days with PB blaster and wd 40.

applied heat with a propane (plumber) torch (all I have)

Used a 6 foot cheater bar and 2 guys to help hold it in place,

broken the OEM removal wrench that came with the drill.

I guess My drill will only do 4 inch holes now.

any great ideas out there?

Yes, I used the copper washer with it to (supposedly) prevent this from happening

Chris Johnson · 04-16-2009, 10:50 PM

Get it hung up in reverse...

Usually works believe it or not, I'm not being smart

FJRFencer · 04-22-2009, 08:49 PM

That might work, if it HAD a reverse

willworkforbeer · 04-22-2009, 08:55 PM

In my first career as a mechanic I found that the very very best lubricant to break stuck bolts etc was old burnt transmission fluid.

Inner10 · 04-22-2009, 10:37 PM

I've used ATF quite a few times, on cars it helps to sock the airhammer to stubborn bolts but I think that was more to break-up the rust. I'm shocked the torch didn't do the trick thats pretty well my 'go-to' method for removing stuck things.

rustyjames · 04-23-2009, 11:36 AM

Sometimes a couple good shots with a hammer (and a steel dowel if you can't get to it) while you have tension on it will work to bust it loose. Worst case scenario would be to cut the bit off; that could probably done with an oxy-ace. setup or grinder.

jcalvin · 04-23-2009, 12:57 PM

I had tried everything to get an old trailer hitch off my truck once, pb blaster, wd 40, tranny fluid. Nothing worked. A friend put me onto Kroil. NOTHING works as good as this.

rustyjames · 04-23-2009, 02:56 PM

I think the problem here is extreme tightness and no amount of penetrating liquids are going to get it to break loose.

FJRFencer · 04-23-2009, 08:30 PM

Quote:

Originally Posted by rustyjames

Sometimes a couple good shots with a hammer (and a steel dowel if you can't get to it) while you have tension on it will work to bust it loose. Worst case scenario would be to cut the bit off; that could probably done with an oxy-ace. setup or grinder.

I cant cut it off, If I do, I would loose a $300 bit and have to re-build the drill with a new drive shaft

Got a link for this kroil stuff? never heard of it.

looks like a gun lube

BHR · 04-23-2009, 08:31 PM

Something like this http://www.canadiantire.ca/AST/brows...g%2BPliers.jsp

Lock it on and tape it so it wont open then hit her with the hammer

rustyjames · 04-24-2009, 09:38 AM

Quote:

Originally Posted by FJRFencer

I cant cut it off, If I do, I would loose a $300 bit and have to re-build the drill with a new drive shaft

Got a link for this kroil stuff? never heard of it.

looks like a gun lube

Yes, it would destroy the bit, that's why I said worst-case-scenario. Someone who is good with a torch can cut that off without hurting the drive, it's done all the time to remove frozen bearings/bushings.