Introduction/ Nose Bolt Vibrating Loose

[Stick&string]

I've been pulling a bunch of information from this forum for a couple years now ( thank you everbody ). I got into chainsaw milling two years ago when i had a massive pecan come down in my yard. I bought ( and still use) a 36" Alaskan MkIII, and a 660. I milled the pecan and several eastern red cedars with it and have been very pleased with the lumber I have got.

I got the opportunity to mill a red oak that some friends had to take out due to the recent ice storms here. The tree is around 40" at the widest. I didn't have the funds to get the longer bar and rails for the mill, so I drilled the bar and drilled and tapped the uprights to get as much width as possible with the set up I have.

I have a hardened 1/4" bolt through the center of the sprocket in the nose. I had originally planned on a fender washer and a lock washer to keep the bolt from vibrating loose but if I tighten it down, it puts enough pressure on the sprocket to make it noticably harder to pull the chain around the bar by hand.

Plan b was to use the fender washer and some locktite to keep it from coming loose. I did some milling yesterday and everything was going well until half way through the afternoon when the bolt vibrated loose. I tightened it and finished the cut but had to keep tightening it during and after each cut.

What can I do to keep the bolt from vibrating loose? The benefits of bolting the bar to the mill are increased width and added safety but it doesn't seem safe to have to keep tightening the bolt that holds the tip of the bar in place.

I'm sure it's probably something simple I'm over looking or just haven't thought of but have any of you run into this?

 

[Macman125]

If you have a nut on the other side, could you not use two nuts and jam them together ?

 

[DonnerParty]

NyLock (nylon insert) nuts work well for me. They have to be replaced every few times you remove them, as the nylon wears out and stops holding.

 

[Runknpap]

Agree with Donner . Thred locker is a pretty decent product too

 

[Stick&string]

The bolt is threaded in to the bottom of the riser on the tip of the bar, there's nowhere to put a lock nut. Unless the lock nut is in between the bar and the riser?

 

[DonnerParty]

You could thread in a stud with a dab of blue loctite, then use a nylock nut on the other end, so the stud stays in place, but could still be removed in the future when/if needed.

You might also want to try a few wraps of teflon tape on your existing bolt. That will sometimes keep the threads from moving enough to keep it in place.

 

[BobL]

You could thread in a stud with a dab of blue loctite, then use a nylock nut on the other end, so the stud stays in place, but could still be removed in the future when/if needed. .

Milling bars require regular flipping to even up wear so the bolt has to be readily removed.
Vibe is a constant problem on CSMs and I remember losing a number of nuts and bolts on mils and CSs until I started using thread locker.
On longer bars I found one way to help dampen the vibe is to use one or even two ocky straps between the mill uprights - like this

 

[DonnerParty]

The stud allows the bar to easily be removed still. Just slide the bar off of the stud instead of completely removing it. Have you not had good luck with the nylock nuts? They have worked well for me.

 

[Stick&string]

Thats what I like about this site so much. Ask one question and get multiple, possible solutions to the problem.
I never would have thought about a bungee cord to absorb some of the vibe, or using a stud with a nut in stead of a bolt.
Thanks for the photo Bill, don't think I would have ever figured out what an ocky strap was!

 

[295 tramp]

bob could you post a few more photos of that mill? that one awesome looking mill.