Follow-up to the stuck tonearm

[Anna-marie Berliner]

I had forgotten to reply to my post and it hasn't been getting any new ones, so sorry I hadn't been replying. But I'm still having the same problem. I'm pretty sure that the problem is in the bearings in the base. It doesn't move at all. There's no information on it other than the parent date, may 29,1917. I have a picture. I'd really like to get this tonearm working again. It goes to the Kimberley phonograph i talked about in a previous post. And thanks for all the suggestions in the last post!

[JerryVan]

It may help to include a photo of the underside of the tone arm mount, to show how it's assembled and what kind of joint was used. This will suggest where it may be stuck and how to approach getting it apart. Most likely however, the arm has swollen tight into the base. Since the base does not appear to have burst open under the pressure, there may be some hope that it's not too tight to carefully press apart, provided decent access is allowed from below, (hence the need for a photo). No matter what disassembly approach is tried, it will be tricky, with no guaranteed outcome.

[Curt A]

It may help to include a photo of the underside of the tone arm mount, to show how it's assembled and what kind of joint was used. This will suggest where it may be stuck and how to approach getting it apart. Most likely however, the arm has swollen tight into the base. Since the base does not appear to have burst open under the pressure, there may be some hope that it's not too tight to carefully press apart, provided decent access is allowed from below, (hence the need for a photo). No matter what disassembly approach is tried, it will be tricky, with no guaranteed outcome.

I agree with Jerry, but I have used an unconventional method for getting swollen parts separated. NOTE: There is no guarantee that this will work and you may need to get a replacement if it doesn't, so don't blame me if this gets damaged.

I would screw the base down to a piece of wood, after soaking the base in a pan full of kerosene for several days or maybe a week. Once it is mounted to the board, spray the base again with a good penetrating oil... Then, using the tonearm as a lever, try gently moving it right to left until you get some movement, however small (the key is "gently" - not too much force or the parts may break). Then spray it again with penetrating oil and repeat the procedure. I have used this type of method successfully on separating swollen pot metal parts and also parts that are rusted together. Once you get more movement gradually rotate the arm, while pulling upward at the same time. Hopefully this will work... Once it is separated use fine grit sand paper to file down the connection on the tonearm and inside the base. Then apply dielectric grease to the tonearm and base connections. This grease is different than normal grease and is used to prevent dissimilar metal parts from seizing up. You can get it an Lowes or at most auto parts places.
https://www.lowes.com/pd/CRC-Technician ... hrEALw_wcB

Hope this provides an answer for you... good luck.

[JerryVan]

It may help to include a photo of the underside of the tone arm mount, to show how it's assembled and what kind of joint was used. This will suggest where it may be stuck and how to approach getting it apart. Most likely however, the arm has swollen tight into the base. Since the base does not appear to have burst open under the pressure, there may be some hope that it's not too tight to carefully press apart, provided decent access is allowed from below, (hence the need for a photo). No matter what disassembly approach is tried, it will be tricky, with no guaranteed outcome.

I agree with Jerry, but I have used an unconventional method for getting swollen parts separated. NOTE: There is no guarantee that this will work and you may need to get a replacement if it doesn't, so don't blame me if this gets damaged.

I would screw the base down to a piece of wood, after soaking the base in a pan full of kerosene for several days or maybe a week. Once it is mounted to the board, spray the base again with a good penetrating oil... Then, using the tonearm as a lever, try gently moving it right to left until you get some movement, however small (the key is "gently" - not too much force or the parts may break). Then spray it again with penetrating oil and repeat the procedure. I have used this type of method successfully on separating swollen pot metal parts and also parts that are rusted together. Once you get more movement gradually rotate the arm, while pulling upward at the same time. Hopefully this will work... Once it is separated use fine grit sand paper to file down the connection on the tonearm and inside the base. Then apply dielectric grease to the tonearm and base connections. This grease is different than normal grease and is used to prevent dissimilar metal parts from seizing up. You can get it an Lowes or at most auto parts places.
https://www.lowes.com/pd/CRC-Technician ... hrEALw_wcB

Hope this provides an answer for you... good luck.

Doing as Curt suggests can be a great help, but keep in mind, that no amount of penetrating oil will ultimately shrink the swollen pot metal. It may however allow for just the tiniest bit of movement needed to disassemble the arm. Keep in mind too, that all retaining screws and fastenings should be removed, (as you would in disassembling any tone arm, stuck or not), before you begin to go to work on it.

Also, if you fasten the arm down, as Curt suggests, do not grab it by its "outermost end", (i.e. near the reproducer), when beginning to free it up. Grab it instead at the bend where it turns down into the base. This will concentrate your efforts, (forces), strictly towards rotating the arm. Grabbing at its outermost end will both twist it, (which you want), and but will also induce forces that will act perpendicular to the tone arm and will unduly and needlessly stress the mounting flange.

I find that when a method like this does not work, then it's best to try to press the arm out of the mount from the underside. That however usually requires a bit of special tooling to engage with the bottom edge of the tone arm, if it's even accessible.

Anyway... best of luck!

[RAK402]

I have never had one that was completely locked up, but I have had a couple which would stick.

Once I had them apart, I mixed light oil with toothpaste to make a rubbing compound of sorts, re-assembled the parts and moved them back and forth until they moved easily (it took several tries). After this, I cleaned the parts really well, put a bit of light oil on things and was done.

This was several years ago and the problem has not recurred.

I am sure there are much better forms of rubbing compound, but that is what I had on hand, at the time, and it worked.

[Curt A]

The reason I soak stuck parts in kerosene or diesel fuel is because it is so thin it penetrates better than oil and is naturally oily... It really does creep into spots that are hard to get at, but usually takes a week to do it...

If you have never used dielectric grease, you should try it... It's used on aluminum engines to keep spark plugs from seizing and many other uses. Since pot metal is made of a combination of different metals, this grease makes sure that the problem doesn't return, also sanding the swollen parts is a necessary fix to remove some of the swollen metal.

[Anna-marie Berliner]

An update, i have gotten it to move just a little bit, not much but it's at least some progress. I at least know it's possible. Thanks for the suggestions I'll have to try them out, if nothing works i might as well try to find a replacement.

[Curt A]

An update, i have gotten it to move just a little bit, not much but it's at least some progress. I at least know it's possible. Thanks for the suggestions I'll have to try them out, if nothing works i might as well try to find a replacement.

If it moves at all, even a little bit, it can be separated. It will take some time and patience but you should be successful. Just keep moving it back and forth until it really loosens up.