Wax-like coating on soft plastic

[DavePEI]

This may have been asked before, but I couldn't find it...

One of the phones I have on display is a soft plastic 302. Over time, it develops a wax like moldy looking white coating which needs to be buffed off every year. This is a real nuisance as I know each year, I am going to have to re-do it.

When removed, the phone is beautiful. I also see similar on the dial rings of some of my oldest 500s.

Has anyone come across this, and has anyone found a more permanent solution than annual buffing?

Another place I have seen similar is on the handles of old plastic handled Stanley push drills... When it is buffed off, they look great, but when it is on them, they look awful!

Seems to me that I might have read at some time that the coating consists of stearates (fats) migrating out from the early plastics over time.

Dave

[TelePlay]

This might help, if it is a mold.

http://tinyurl.com/83skkja

[Bill]

I agree with Telepay - it sounds like mold to me. You can buff it off the surface, you can even sand down a bit to get it off and expose a new surface. But the mold is deep in the microscopic pores of the plastic, and it will come back, especially if you live in a humid climate. You need to kill it once and for all.

In addition to the thread already noted, there was another discussion of mold here.

http://www.classicrotaryphones.com/forum/index.php?topic=5260.0 The idea of mold doesn't show up until post #14, so be patient as you read.

Bill

[HarrySmith]

I have had that on some of my older 500's, and some 5302's, it seems more apparent on the number rings. I have cleaned it off in my usual manner with soaking in Oxiclean. I have sold the phones so I cannot tell you if it returns. I do not think it was mold, it did seem more like a wax coating.

[Doug Rose]

Dave...is is truly a softplastic set or is it a thermoplastic set. 302s were made for a very short time in softplastic,  color sets with painted handsets to match in the mid 50s. A picture would help of what you are seeing. I have found mold on sets I had stored in the basement where its a tad more moist. The attic gets to hot and you get the bends.  Once I have cleaned off the mold it never came back in a good display environment. Lets see what you have....Doug

[DavePEI]

Dave...is is truly a softplastic set or is it a thermoplastic set. 302s were made for a very short time in softplastic,  color sets with painted handsets to match in the mid 50s. A picture would help of what you are seeing. I have found mold on sets I had stored in the basement where its a tad more moist. The attic gets to hot and you get the bends.   Once I have cleaned off the mold it never came back in a good display environment. Lets see what you have....Doug

I'd show it to you if it weren't over in the museum right now. I am pretty certain it is not a mold - I have used fungicides before on it, and it will redevelop, and has a very waxy feel to it. There are only two sets in my collection which have this problem, and always the same two, and only the one Stanley push drill. Out of the 200 or so 300 series and 500 series phones in the museum, it is only those two phones and the drill which exhibit this phenomenon. It will not wash off, and heating the plastic makes removal much easier with buffing.

In the old days calcium stearate was used as a component in some plastics and over time, that can migrate out of the mix.

I will have to take a photo of them in the spring when I do my cleaning.

Dave

[AE_Collector]

Lots of that going on here as well on my oldest plastic AE's. As you say, very frequently the number rings. I've always assumed it was mold of some sort as it seems to find the phones I have in storage much more than the ones out on display. And no shortage of moisture here in Vancouver!

Terry

[bingster]

This happens with Tenite radio dial escutcheons, too.  I've seen postwar Zeniths that have black Tenite dial surround parts, and they've gone totally white with the stuff.  I've always used hot water and bleach to get rid of it, and it doesn't seem to come back.