View Full Version : how to get nut off of horizontal arbor????

12-10-2004, 07:14 PM
i picked up a B&S No. 2 Universal last spring and it came with about a 10" slitting saw on one arbor. for the life of me i can not get the nut loose to take the saw and spacers off of the arbor!!!!! i believe it is lefthand thread (i hope so, otherwise i have been tightening the heck out of it). any ideas? how hard can i smack this thing without cracking something on the arbor? how hard are the lefthand nuts to find? i'm almost to the point of just cutting the nut off. it hurts just saying that.

andy b.

charlie coghill
12-10-2004, 08:02 PM
Just for fun see if it is a right hand nut. Some things are not what they should be.

12-10-2004, 08:25 PM
The arbor off my old horizontal mill is right hand thread.

Forrest Addy
12-10-2004, 10:12 PM
Yup. Everything is keyed together. All arbor nuts are RH.

If someone slugged it up obscenely tight you can always warm up the arbor slowly to 300 degrees then quickly chill the spacers with cold water. The spacers will shrink and the arbor will stay warm. You can remove the nut with your fingers if you're quick and the arbor is long enough.

12-10-2004, 10:15 PM
well, it has L.H. stamped into the nut, and the other arbors that came with it are all lefthand. i will try to get a better look at it in the light tomorrow. maybe it was a lefthand nut they stuck on a righthand thread??? now THAT would be a bugger to get off.

is there a chance this nut is heat treated? how hot can i heat this thing before i damage something? i have a feeling it will be getting cut off.

andy b.

12-10-2004, 11:14 PM
You could try using some dry ice on the arbor bushings. Wrap the bushings in dry ice for about a half an hour. To remove a LH nut you turn the nut clock wise viewed from the nut end. When I purchased my Pedersen Universal Mill it came with 2 arbors that were LH thread and 5 arbors that were RH thread, I also had a very stubborn arbor nut (it turned out to be a LH thread also), I think it had been assembled with a large saw for at least 7 yrs ( that's how long the school that I purchased it from has not taught machine shop), boy did it stink when I took the spacers off!!! Our 3 millers at work all have RH threads on the arbors.

Another way to relieve the tension on the nut is to place the arbor in a lathe, then using a cutoff blade mounted in a tool post grinder , grind away one of the thinner spacers, check with calipers so you dont grind into the arbor shaft.


Robert Jones
12-11-2004, 11:15 AM
If you should destroy it taking it off, www.grandtool.com (http://www.grandtool.com) sells left hand arbor nuts in various sizes, Bobby

[This message has been edited by Robert Jones (edited 12-11-2004).]

12-11-2004, 09:55 PM
use an impact wrench and let it rattle on the nut for a while and then it should come
right off.

12-11-2004, 10:24 PM
<font face="Verdana, Arial" size="2">Originally posted by Yankee1:
use an impact wrench and let it rattle on the nut for a while and then it should come
right off.</font>

The nuts are rarely hex nuts - almost always (never seen them any other way, actually) only have two flats for Mr. Wrench.

12-11-2004, 11:54 PM
i double-checked it tonight. lefthand, and two flats, like Thrud said. and it has probably been assembled for several years as well. i like the ideas to heat everything and cool the spacers down. i'll give that a try and see what happens. if i have to cut the nut off i can buy a normal lefthand nut and use my recently fired-up shaper to make two big flats on the nut (sure i don't need to, but i have to find SOME use for a 3000 lb. hunk of cast iron taking up 10 sqr-ft of floor space).

andy b.

12-12-2004, 12:06 AM
left hand makes sense, if the arbor spins to the right.