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Dale Lusby
12-03-2010, 01:53 AM
I have a Walker Ceramax mag chuck that has never really worked right. It doesn't let go all the way when turned off and doesn't hold quite as good as it should either. I took it apart assuming the magnets weren't lining up and after opening it I was surprised at the waxy nasty mess inside. I assume it isn't supposed to be this way and it's residue from a previous life of hard labor. Would it likely be dried coolant? Is it supposed to be clean inside? Everything seems to be working properly and I assume the issue is the stickiness that is making it so hard to move. Is there another adjustment to line up the magnets properly? Any ideas are much appreciated.
Thanks,
Dale

Walter
12-03-2010, 04:20 AM
Dale,

I'm no expert but I did stay at a holiday inn express last night... wait, wrong fiction.

I just did a rebuild on a suburban mag chuck. I can't speak to your waxy mess, but they do need lubrication for sliding. More likely is the linkage for moving the mag block, if it's not releasing then the poles are staying engaged, hence the block isn't moving to the proper position. IF you have any play / slack in the mechanism that's most likely the problem.

JoeLee
12-03-2010, 09:22 AM
I had a Walker 6 x 18 that had the same problem. Thier design for the linkage that moves the magnet pack back and forth isn't the best, and it does take a substantial amount of force to move the magnet pack, more so after the grease dries out or contaminates have creeped in. After the linkage starts to wear the magnet pack doesn't move the distance it should for proper on / off. Also if there is still some magnatism left when in the off position and there could be a problem with the shorting straps inside. They were two thin strips of metal. In the chuck I had they were badly corroded as the chuck was full of water. It must have been used on an EDM or something. Once they get wet inside your done.
Calling Walker wasn't much help, they'll just tell you to send it in.

JL...........

Dale Lusby
12-03-2010, 11:07 AM
I will take another look this evening and see what I can come up with. I tried to slide the magnet but dang it sure has a lot of holding power. Not sure how I'm going to slide it off but hopefully I'll figure something out. What lube should I use? I've heard gear oil for bottom and a heavy grease for between mag and chuck. Sound right? I'll be getting to cleaning first and see where it goes. All in all it seems to be in decent shape. The linkage didn't look too worn but I wasn't looking too close.

JoeLee
12-03-2010, 11:41 AM
You have to be careful prying out the magnet pack, don't pry it from the ends (lengthwise) because it's flexable in that direction or you may snap it. Lift it up from the sides. 90 weight gear oil is what was reccomended. Inspect the linkage for wear, the parts ar not hardened an and become sloppy in a short period of time resulting in a lot of handle movment and incomplete movment of the magnet pack. Also I would clean both sides of the magnet pack, 320 grit sandpaper and WD-40 works good. Both sides should be clean and smooth and do the same with the two shorting straps, they have to make good contack across all the polls of the pack or you may end up with some light magnatism when in the off position.

JL.......................

rmuell01
12-03-2010, 03:05 PM
I had the same gunk in my suburban chuck and I cleaned it out and repacked it with red grease. I worked it while it was opened and it started to work fine. I also put some gasket stuff the seal and this seemed to really help.

Rob

Dale Lusby
12-04-2010, 12:43 AM
First off I want to thank everyone that commented. Very helpful information. I will be cleaning it this week. It appears the linkage is worn as the bore is .438 and the pin is .305. Seems that is about what the alignment is off. I'm think about making a bushing to fit in the bore that has a slight shoulder to keep it from sliding out. Would this be advisable? Any particular metal you would use? Would bronze hold up to the use? It's not going to be used too often so wear probably will be slow.