handset ring rehab

[suhoni56]

My Carlson Stromberg arrived, and it looks good except for the ring on the handset. It is badly discolored. It looks like possibly glue residue that has been cleaned off. I was able to chip a small piece off with my fingernail, but for the most part, it doesn't appear to have any thickness. In one place, it seems to have changed shape right along the edge in one small spot, but it does still thread on. Maybe it should be gently filed flat?

Advice for restoring?

[TelePlay]

You might want to try Brasso with 000 steel wool in one small spot and if that works, continue on. You may want to use 0000 steel wool. If it's a bakelite ring, that should work.

http://www.classicrotaryphones.com/forum/index.php?topic=12264.0

[suhoni56]

Thanks, I will try that. This is the little place I was thinking I should maybe file flat, on the edge.

[TelePlay]

Ah, now I see, but not well.

Can you take and post a picture of that area without using the camera flash? Using sunlight or a bright diffuse, indirect light would make it easier to see what you have there. Thanks.

[rdelius]

Those rings were of  2 types.Yours is thermoplastic.They also has fragile bakkelite ones.Kleenax makes replacemenrts.The ring on the all metal WE linemans handset will fit.

[suhoni56]

Here are some better pics. Probably will go with the replacement. What would be y'all's first choice?

Thermoplastic? It sure looks like bakelite. I wish I had seen more/knew more.

[TelePlay]

Good photos.

One quick check for bakelite vs plastic thermoplastic is to heat up a thin needle or pin and then carefully stick it into an inside area, a place that can not be seen. If plastic thermoplastic, it will melt its way in and if bakelite, it won't.

[unbeldi]

Good photos.

One quick check for bakelite vs plastic is to heat up a thin needle or pin and then carefully stick it into an inside area, a place that can not be seen. If plastic, it will melt its way in and if bakelite, it won't.

Substitute plastic with thermoplastic.

Thermosets are plastics too, and most people do consider Bakelite a plastic. It is a thermosetting plastic.

[TelePlay]

Substitute plastic with thermoplastic.

Done, my error.

So, what about the "bump" on the ring? If bakelite, would it be worth removing? If thermoplastic, same question? Or find a replacement? Seems like a simple fix to remove.

[unbeldi]

Seems to me this may be some kind of rubber, or vulcanized rubber (hard rubber), but a thermoplastic is possible too, I suppose, perhaps it got too hot somehow.

The SC 1190-series all used the same handset, it seems.
The only description I can find quickly is this:

The handset, stand and cradle ... are made of black moulded phenol compound presenting a rich black polished finish that is permanent.

I would be surprised if they used a thermoplastic for parts of it. At that time, I believe, thermoplastics were used only for colored parts.