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Peroxide treatment on a yellow phone

Started by McHeath, December 04, 2011, 01:05:55 AM

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McHeath

So has anyone ever used the peroxide bleaching process on a yellow phone?  I've got a nice yellow, code 56 pastel yellow, 500 from 1962 with a fair amount of nicotine discoloration.  Being that I really really don't like sanding and polishing, I'd like to use the peroxide trick. 

But I know that on colors like green the peroxide can be a disaster.  Yellow seems like it might be iffy, so I don't want to possibly ruin a good phone.

HarrySmith

I used the retrobrite formula on a yellow phone and I got blotchy results. It was one of my first tries. I think it was from uneven application of the paste and/or uneven UV exposure. It was a junk phone so I sold it blotchy anyway. I think the results with a more controlled application and exposure would have been fine. Some have gotten good results using just a liquid formula, more even coverage.
Harry Smith
ATCA 4434
TCI

"There is no try,
there is only
do or do not"

GG



As I've mentioned elsewhere, that discoloration isn't actually "nicotine."

Nicotine is powerful enough stuff that the quantity of it needed to discolor a phone would be sufficient to make you sick by handling the phone (nicotine is also used as an insecticide). 

The discoloration could be due to other compounds in tobacco smoke, wood smoke, cooking smoke & fumes, and so on, or any combination of these.  If the phone is "sticky" to the touch, it is likely to be volatilized oils from cooking, that deposited on the phone and accumulated. 

Humidity, dust, and air pollution can also do a number on phones.  The solid particulate matter from diesel exhaust consists of tiny black particles that may seem "gritty" or may leave streaks when disturbed. 

Different cleaning methods & compounds may be needed for each of these.


McHeath

Yes good point GG.  This phone is not sticky, it has a brown cast over the surfaces, that is not under the handset horns, nor inside the dial and housing or handset caps.  It also has an old stale cigarette smell, or had I should say as I gave it a bath. 

I'm probably going to try the peroxide treatment mainly because I don't like sanding.  I once had an aqua 1500 that was impossible to remove the brown from, it was an incredibly deep stain.  I sanded on that phone for hours and eventually the shell got thin and started to crack.


GG



If you were able to clean off the stale cigarette smoke smell, then it's likely that the staining is something else and may be fading due to sunlight. 

Sunlight is powerful: 1000 watts per square meter*, or about 75 watts in the area occupied by a phone.  So think of a 75-watt light with a decent quantity of ultraviolet in the spectrum, hung right above that phone for decades. 

I have a couple of TeleNorm (Germany) flush panel wall sets, that have light green plastic handsets with ivory transmitter & receiver caps (standard TeleNorm colors).  These were on the walls in a doctor's office.  The sunlight caused the transmitter and receiver caps to turn brown and decompose: the plastic cracked and peeled away in layers. 

The dials and hookswitches were apparently resistant to sunlight.  One could replace the handsets with any G-type handset and then make use of these again, or render the sets down for parts.  But anyway, those transmitter and receiver caps are a serious lesson in the power of sunlight to destroy certain kinds of plastics. 

Re. McHeath: that's why I don't use sanding as a treatment; there is no replacing the plastic that's lost in the process, and the result is to compromise the strength of the housing.  IMHO sufficiently serious fading = the plastics are a write-off, use the rest of the components as spare parts for other projects.  Alternately if we could buy Polane and apply it the way Bell did, we could at least put these things back into a condition that's serviceable. 

---

*1000 watts per square meter: This is why research into new photovoltaic materials is so darn important.   The energy just waiting to be tapped that way is more than sufficient to meet all of our needs without ecological hazards or dependence on unfriendly foreign governments. 

Dave F

Quote from: GG on December 07, 2011, 03:43:39 AM

Sunlight is powerful: 1000 watts per square meter 


Actually, the average annual sunlight arriving at the top of the earth's atmosphere is approximately 1360 watts/sq. meter.  However, with atmospheric attenuation and local cloud cover, the annual sunlight reaching the ground is only about 164 watts/sq. meter when averaged over the entire surface.  Therefore, the amount of UV available to fade our phones is highly dependent on the amount of light coming through a particular window at any given place and time.

kleenax

#6
Here's the "official" RetroBrite web thread. I would think that with as much research that these gents put into this project, it is well worth reading again.

I've experimented a bit with it, and yes, I will write up my formulas that I got to work, but simply re-reading the original posts by these guys will refresh all of our memories.

Link is here to Retrobrite: http://retr0bright.wikispaces.com/

After my experiments, and hearing about the "blotchy" results on various colors, I might do some "diluting" of the formulas to see if that would both lift the yellowing, and preserve the original colors.

There is also some VERY interesting reading in the left margin of the Retrobright site too. Click on the links under that heading of "Science Bit", and you will find out what REALLY causes that yellowing and discoloration in ABS plastics. The topic of "UV Energy" I found particularly interesting.
Ray Kotke
Recumbent Casting, LLC

GG



I'm seriously looking forward to getting standardized formulae for this stuff: specific brands and quantities of ingredients, and make & model number of UV light sources.   Presumably the goal we're working toward is a "dunk tank" with liquid solution in it, and with aluminum foil on the sides to reflect the UV light into the tank uniformly.  (Question is, can the solution be kept in the tank for treating a bunch of phones in a row, or does it decay or "wear out" in some way?)

I have a back-stack of phones to process, including a '50s Swiss dial phone that should be ivory but is rather seriously yellow, an Ericsson 6DLG in medium blue that got a mild but noticeable fade, and the usual batch of WE, AE, GPO, etc.

Potentially useful thing for the UV light: a timer switch. 

You can use any programmable appliance timer, or get a Dayton windup timer switch that can be set for a period of hours.  If anyone's interested I can go find the correct model number of windup timer switch. 

The point of this being, the timer switch enables letting the reaction run overnight or any time you're not watching it, and when the UV light switches off, the reaction goes into hibernation until after you check it and determine if it needs to continue. 

Another thing we need is a list of plastics & colors for which this does not work and causes harm. 

Lastly it would be highly useful to have a source for standard UV light meters, for use checking ambient lighting conditions in rooms.  For example "does my brand of compact fluorescent lights emit UV that could fade the equipment on display here?"  Assume that sunlight is the worst condition (most UV), and an incandescent bulb is the best UV condition (no UV) for purposes of associating the readings with known good and bad conditions.