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Possible telephone case/shell yellowing reversal: READ!

Started by BDM, March 05, 2009, 01:48:27 PM

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St Clair Shores, MI


B, can you advise on when they started using ABS?  I have a seriously yellowed, originally white Trimline from the 70's that could use some "retrobright" action.


Dennis Markham

Ralph, the use of ABS plastic began to phase in during early 1959.  Soft plastic examples have been known to show up as late as 1964 however.  As Paul Fassbender mentioned, they didn't just throw a switch and begin making them with ABS (hard plastic) all at once.  Material was used until it was depleted.  Certainly Trimline sets would be hard plastic.


The process they describe, is not unlike that used for whitening teeth....
It very well might work, but I wouldn't expect results like they show, The Commodore case looks artificially darkened, I have a 64 that been in a very warm area, stored for the better part of the last 10 years, and it barely discolored at all.


The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson


I'd love to try this out, but it's an expensive prospect.  Amazon has 12% peroxide solution (drug store peroxide won't work) for $13.27 for a 12 oz bottle.  A gallon would cost $106.  The solution apparently only lasts four days.  I suppose it would be worth it if you had a large collection of yellowed phones, and could get them all done during a four day marathon, though.


Thanks for posting this-I'd love to give it a try.

Regarding the higher concentrations: you can generally keep them around a lot longer if they're stored in the refrigerator. We keep 30% on hand here, and a bottle will generally stay close to that for 1-2 months.

One brand of pool disinfectant contains a relatively high concentration of peroxide-I don't recall the brand off hand, but it may also be a viable solution that should be available locally(or at least will be in the next week or two). With the Amazon product, I suspect that you'd probably have to pay more in Hazmat fees to get it to you than you'd pay for the item itself.

Also, just as a word of warning: 3% peroxide is relatively safe. Anything much above it is really, really nasty stuff to handle. In other words-wear gloves. You don't want it in contact with your skin.



St Clair Shores, MI


I am going to try this on a white phone that looks almost ivory from yellowing. I am also going to "force" the wifey to take digital pics for me and hopefully we can see some results.
"Imagine how weird telephones would look if our ears weren't so close to our mouths." - Steven Wright

Dennis Markham

Dan, a member of the ATCA posted info and pics claiming success in this method of removing yellow.  I was running short of time and just briefly skimmed over what he had to say.  But it sounds like if the procedure is followed to the "T" it is successful.


Thanks, I got two  WE500's (1959's) from craigs list , one soft, one hard, both white (now yellow). I will try it on the hard plastic one first. It would be extremely helpful on whoever won that Mediterranean Blue one you just pointed out.
"Imagine how weird telephones would look if our ears weren't so close to our mouths." - Steven Wright


Well, As you know I have no digital photography skills, but I am going to report my experience with this hydrogen peroxide  experiment. IT REALLY WORKS GREAT!!!!!


1. Sodium Carbonate
The cheapest form of this is not the "oxy" detergents at the stores, but rather
Arm & Hammer Super Washing Soda. Krogers, 3lb 7 oz box-around $4

2. Hydrogen Peroxide 20% -called wella Color Charm volume 20 (means 20 % h2o2)

Sallys Beauty supply house- I quart  $5.00(get the clear liquid NOT the cream)

3. The hard one -Arrow Root Starch/Flour . Very expensive. 20 oz bag (smallest I could find--$7 at a local natural food store. I bet corn starch @ the Kroger for .99 cents may work, but I followed the formula precisely.

I started with the 10% formula (1/3 cup 20% peroxide, 1/3 cup water), but all subsequent applications I used 1/3 cup peroxide (abbrev. H2O2) , than divided the other 1/3 cup into 1/2 of it water (H20), 1/2 H2O2. (ends up being 15% concertration-which has worked better.
Mix the 15% mix with two heaping tablespoons arrowroot in microwave 15 secs, stirring every 15 secs. After about 45 secs total, it will get very thick, like shaving gel consistancy.This is the thickness you want.

Add heaping 1/2 teaspoon  Arm and hammer "oxy"to the hot H2O2 gel and it will froth and bubble up nicely.

The Phones Cleaned up.(oxygenated)

1.WE500 Light Blue ( slightly yellowed but not turquoise yet)

2. WE500 1962 White, badly yellowed

3. White princess 1966 -almost dark tan, lift the handset and where the cradle sat it is white

4. 1959 Soft  plastic tenite white WE500. Yellowed a lot, not as bad as #2

I took the caps off and took the dial plates off and the housings off. This mixture will treat  two housings, two handsets and caps .Paint the phones with a brush. THICK almost like frosting a cake.I did not have the patience of the retrobrite guy, who had a thinner mix and reapplyed it every hour after it dried. The thick mix stays wet for HOURS.
Set the phones under a 100 watt regular (not fluorescent ) bulb. Leave alone for six hours. After three or four, it looks like they aren't doing so well but once six is up, rinse off the phones in warm water (or wipe the handsets off with a warm wet wash rag since you can't immerse them. I taped off the insides of the handset with masking tape to prevent gel from going inside.)

1. WE light blue worked well, needed two applications, six hours each.

2. White 1962 hard plastic. Worked, but needed three applications to finally approach the whiteness of the inside of the caps and housing.

3. Soft plastic 1959.  I was affraid of the soft one, being more valuable, but the results were great. I did two applications to get her beautiful. Whitened a little easier that the thermoplastic.

4. Princess--the biggest bear yet, on it's fourth round, but it will get there.


I am finally just doing them before bedtime now for  6 to  8 hours, it doesn't matter timewise after six hours , I believe.. Wipe them off when you wake up. Put a nice wax on them after you are done.
This sure beats sanding. Wash your hands a lot (or wear gloves), but you won't get burns or peeling. (they use 6% H2O2 on teeth bleaching, so it isn't that caustic).

If Someone with photography skills could do this, you will see what I mean!
"Imagine how weird telephones would look if our ears weren't so close to our mouths." - Steven Wright


Very interesting, Dan! How did you figure all the chemistry out? I hope to see this in the Technical Library once someone can do the same experiments and add some decent photos.  Truly amazing if some of the fading and discolorations can be treated with chemistry instead of sanding.  Hey Heath, are you gathering Dans' list of ingredients soon? ;)


here's a picture of an ericophon that is very similar to the princess I am trying to oxygenate:
"Imagine how weird telephones would look if our ears weren't so close to our mouths." - Steven Wright


Quote from: Dan on March 28, 2009, 12:35:33 PM
here's a picture of an ericophon that is very similar to the princess I am trying to oxygenate:

YIKES! That will need some work. Those open white patches are strange. Maybe the seller removed stickers? Though, my experience with stickers has never been good, nor that easy to remove.

St Clair Shores, MI


Well, I switched the formula to Salon care 40 volume clear sold at sally's beauty supply. After three overnight applications, I had a DARK yellow (WE white500) looking like my refrigerator. The 40%  hydrogen peroxide  cleans them quicker and faster, so I would recommend this.

Actually, it looks just like this phone from finlover

here's a former before picture (not my actual phone but just like it

"Imagine how weird telephones would look if our ears weren't so close to our mouths." - Steven Wright