511ax repair /mod and similar units

[blades]

Howdy all, the other day got into a large group of .325 - .050 lp type chains, various mfg. My 511ax units were giving me some fits with these. Took just a bit to figure out why. Vise not closing properly -infact when tightened the drive link clamps loose their grip hence the difficulty due to the cutter dancing around some.
Cause of problem is not dirt, grit , loose screws or wear factor on the drive link clamps. It is a design shortfall between the upper replaceable jaws the the mounting blocks beneath same. The jaw mounting blocks meet first causing the drive link clamp bars to open up. Simple remedy is to shim one of the upper bars with a small thin washer behind each mounting screw ( or any type of shim material you might have apx 1/16" max.) doing so will cause the drive link clamp bars to close prior to the lower mounting blocks meeting.

Thinking on this a bit more there could be a wear factor in the vise screw assembly. I did not tear that section down as I did not notice any obvious malfunction there as far as transportation of the lower mounting blocks was concerned.

 

[w8ye]

Early wear of the plastic parts of the 511AX vice has been documented on Arborist site before.

 

[blades]

I did do a search didn't find anything addressing what I posted- may not have used the right terms. at any rate it is a quick and dirty fix that solves several issues that did come up.
I do several hundred chains a year so I am not an average user. I am fully aware if the left /right swivel wear in the base which is why I use 2 units one set for left one for right never gets changed. Otherwise I would be buying a new swivel assembly every year.
There could be wear in the plastic bushings - that didn't seem to be the problem as the lower half of the jaws were meeting prior to the chain drive link clamp portion. Wear on those bushings I do not believe would cause the problem I am referring to. I did not notice the problem on the on side cutters due to wheel rotation , but on the off side cutters. Adding the shims/washers behind the on side clamping bar resolves the issue for next to nothing cost wise.

 

[Philbert]

Can you add some photos?

Here are some links to related threads on the 511AX vise:
http://www.arboristsite.com/community/threads/511ax-vise.228345/

http://www.arboristsite.com/community/threads/has-anyone-used-the-oregon-511a-and-the-511ax.261521/

Philbert

 

[blades]

Philbert I will take camera with me today, I have about 30 chains for a tree service to do, typical need them yesterday job - as they didn't drop any off when they picked up the last group a couple weeks back. You really do not notice it with larger chains as the drive links are deeper in the vise but when you have to do the 325 or picos it will jump out at you. Even the 3/8 by .050 N1 Carlton or similar will show it up a bit, as the drive links are not that deep. So basically any chain used on the 36cc or electrics class saws would be affected. You can put chain in vise tighten and the lift chain right out of vise with out loosening the clamping handle. Not a wear factor at the top of vise drive link clamps .

I will look at those bushings you have shown it is possible that may be the cause. I did not tear the vise assemble that far down.