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Does anyone have a good way of removing a bad pot metal bearing that's common on the later Edison Standards, Homes, and Triumphs? I was able to get the mandrel shaft out and then I drilled smaller holes in the old bearing and generally beat up the poor little Home. I felt like I was being too rough on the machine by using a screw driver as a chisel and clobbering it with a hammer. I was successful but wondered if there's a better way. Thanks for any suggestions. Jerry

Jerry,
This was discussed on another forum a couple of years ago. Some collector pointed out that a chemical could be applied to the pot metal which would dissolve the pot metal but not harm the casting. I can't remember what it was, maybe someone else remembers. I'll keep looking though.
Dave Jolley

Jerry,
I found it:
You need an eye-dropper, a small glass bowl, and some muriatic acid.

Remove the screw on top of the beaing boss (the hollow one that holds the bearing in place), place a piece of plastic bag over the bedplate to protect the paint, and using the eyedropper drip six or seven drops of huriatic acid into the hole.

Allow the acid to do it's work, dissolving the pot-metal, and cleaning the rust off of the steel shaft, for about twenty minuites.

Check to see whether the mandrel can turn freely.

If not, add another five or six drops of acid to the screw hole. repete until the old bearing is dissolved and the mandrel assembly can be easily removed from the machine.

Dave Jolley

Thanks for the suggestion. Where's a good place to get this product? It sounds much easier that the process I went through today. Thanks, Jerry

Jerry B. wrote:Thanks for the suggestion. Where's a good place to get this product? It sounds much easier that the process I went through today. Thanks, Jerry

Jerry,

Muriatic acid is used to clean masonry and to shock swimming pools. You can easily get it at any hardware store, masonry store, or pool supply. You will probably have to buy an entire gallon.

Jerry,
Be very careful handling this stuff. Wear rubber gloves, eye protection and work outdoors, avoid breathing the fumes. I use it for a variety of things and if you take the necessary precautions, it's safe, just be careful.
Dave

Right, muriatic acid is sold by the gallon at hardware stores. It's HCL acid, IIRC; you could google it up and find out. I use it to dissolve the gray crust that forms in the toilet as a result of the very hard water we have; the crust is really calcium carbonate (limestone!). The muriatic soak really does the job on this stuff.

Henry wrote:Right, muriatic acid is sold by the gallon at hardware stores. It's HCL acid, IIRC; you could google it up and find out. I use it to dissolve the gray crust that forms in the toilet as a result of the very hard water we have; the crust is really calcium carbonate (limestone!). The muriatic soak really does the job on this stuff.

Perhaps a bit off topic, but does the muriatic acid damage the porcelain in toilets? I would love to find a solution for the hard water deposits in our toilet bowls, but I fear that anything strong enough to break down the deposits may compromise the integrity of the glazing on the porcelain, (i.e., make it so porous that it just introduces a new potential set of problems). Opinions?

I do about 10-15 of these per year, and here is how you remove the bearing. Now, I can not explain how to remove the mandrel shaft from the seized bearing, but it always involves use of light oil, and twisting the shaft with some strength to remove it. In EXTREME measures, I remove the mandrel from its shaft and put vice-grips on the shaft to turn it loose, then re-soldering the mandrel on later.

On an Edison HOME: I take a hack-saw blade to a bench grinder and shorten its height (take a little off the top), so you can use the hack saw blade inside the old bearing to cut through it. Then, tap it out with a drift and a hammer. Remember to remove the small set-screw in the cast iron casting before removal!

On an Edison Standard: I heat the bearing GENTLY with a small torch, then tap it out with a larger diameter drift and a hammer. Remember to remove the top oiler screw, because it will hold the bearing in place otherwise!

I have this job to do on my Home at some point. I've been putting it off. Out of interest where is the best place to get a replacement bearing from?

S-B-H