Classic Rotary Phones Forum

Telephone Identification, Repair & Restoration => Telephone Restoration Projects and Techniques => Sanding Plastic - Paper and Chemical Tips & Techniques => Topic started by: cihensley@aol.com on July 01, 2011, 02:45:30 PM

Title: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 01, 2011, 02:45:30 PM
I have chosen an old WECo pink 500 to experiment with solvent polishing. I chose this set because if the restoration is successful it is a desirable set - an 8/59 all numbers matching, and it will require most of the techniques discussed on this Forum. And, I have an NOS pink 500 to compare the finished product with.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: HarrySmith on July 01, 2011, 05:52:18 PM
Nice! i cant wait to see the progress. Are you using the techniques in the bulletins you have?
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 01, 2011, 06:10:26 PM
HarrySmith:

Yes, partially.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: jsowers on July 03, 2011, 08:26:02 PM
Chuck, with a date of 8-59, it could have some soft plastic parts and that dial face looks to be soft plastic because it's faded a bit lighter than the rest of the phone. Hopefully the solvent won't dissolve the soft plastic. I know denatured alcohol will dissolve soft plastic and it's a mild solvent. Just wanted you to be forewarned, just in case.  A test from the back of the dial face should tell you if it will withstand the solvent. And the fingerwheel is not the original, which I'm sure you know already.

What are you planning to do with the bad crack on the right front corner? Or is that a crack? It looks like some of the plastic is actually missing there.

Keep us posted on your efforts.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 03, 2011, 08:50:06 PM
I'm really looking forward to the results and the chemicals you use and find successful. The WE patents used hard to get chlorinated solvents specific to the plastic. DCE and Freon , neither of which were flamable, were misted into a chamber having an elevated temperature to both soften the surface and reflow the plastic to fill dings and scratches. While there are several commercially available solvents that will soften the surface, they are all polarized organic solvent which when heated create an explosive environment. What they did makes sense and their refurbishing equipment, machine, automated the process. Are you planning on using methylene chloride (DCE) and if so, is it available to the common many without major licensing hassles?

In the end, I am really looking forward to hearing about what you discover in you experiments and thank you for trying.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 03, 2011, 09:41:24 PM
jsowers:

Yes that is a crack. I plan to fuse it using dissolved plastic from a rib inside the phone. I am not sure what is hard versus soft plastic. Can you suggest a method to determine?

TelePlay:

Methylene Chloride is available to order. I found mine with a "where to buy" query on Google.

Chuck
Title: Re: Restoring a WECo Pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 04, 2011, 01:40:49 PM
An update. The first picture shows the embossed areas dammed off with Blu-Tac, to hold V30 hydrogen peroxide to restore the color. The next picture show the results, which were not good. I left the V30 on for 5 hours. This same method worked very well on the blue 500U I restored. I don't know if the color went from salmon to desired pink to bleached, and if I had stopped sooner it would have been OK, or if it went directly from salmon to bleached. On to plan B.

Until I fully determine which components of the pink 500 set are soft versus hard plastic, which has a bearing on the solvent used, I decided to experiment on an old modular 500 that I knew was all ABS. The third picture shows the badly discolored white set I experimented with. The last picture shows half the phone (your left) wiped with methylene chloride and the other half sanded with 1500 grit micro-mesh. I was not intending to get all of the discoloration, just enough for a comparison. The methylene removed the discoloration in about 6 swipes with a saturated rag. Marks from the rag and lint from the rag pulled by the sticky (dissolved) plastic are evident. But the plastic is shinny from the methylene. This suggests that my plan to sand the pink phone then mist it with methylene using an airbrush may work. Yet to be determined with further experiment is what grits will the methylene smooth out.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: jsowers on July 04, 2011, 02:59:47 PM
Quote from: cihensley@aol.com on July 03, 2011, 09:41:24 PM
jsowers:

Yes that is a crack. I plan to fuse it using dissolved plastic from a rib inside the phone. I am not sure what is hard versus soft plastic. Can you suggest a method to determine?

Chuck, I use the tap of a fingernail on the plastic. Soft plastic will have a duller sound. Hard plastic will have a sharper sound. It may not matter which kind of plastic it is, if you're going to dissolve part of it. But they are different formulations and what dissolves one may not dissolve the other. The WE patent info was circa 1969, so I was thinking it was designed for hard plastic.

On a hard countertop or steps is a good place to tap the plastics. You can get known hard plastic and soft plastic pieces and you'll be able to tell the difference in sound fairly easily. Also, pink soft plastic fades light and pink hard plastic gets that salmon color, which is darker.

You may have to test on the backs of the plastics to see what happens before you try it on the outside. And avoiding those logo areas will be hard to do. Also the stamped dates--maybe you can use Vaseline on those areas?

Good luck and keep us posted.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: LarryInMichigan on July 04, 2011, 05:18:57 PM
I am anxious to hear how the dissolving and patching process goes so that I might be able to use the information to repair a section of the tenite shell of a blue AE80.  Please keep us posted.  We are on the edges of our seats.

Larry
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: AE_Collector on July 04, 2011, 05:33:00 PM
Quote from: LarryInMichigan on July 04, 2011, 05:18:57 PM
I am anxious to hear how the dissolving and patching process goes so that I might be able to use the information to repair a section of the tenite shell of a blue AE80.  Please keep us posted.  We are on the edges of our seats.

Larry

Now that you mention it, my dark blue (Colonial Blue) AE80 had a piece busted out of the side of the case but fortunately all the pieces were recovered and glued back into place. Maybe a better repair will be possible with this method.

Terry
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: rdelius on July 04, 2011, 05:39:05 PM
We tried at COT using acetone or a similar solvent on discolored hard plastic sets.It helped remove the yellowed layer and we did not have to sand as much. It still was not the answer.No bleaching back then.
Robby
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 04, 2011, 08:36:30 PM
jsowers:

Thank you. They did sound somewhat different. Based on the fingernail/sound test, I picked the handset and its two caps as being soft plastic, with all of the other components being hard plastic. To resolve any doubt I remembered you saying, in a couple of posts, to never use denature alcohol to clean soft plastic. I put a couple of drops of denatured alcohol on the inside of each plastic component. On the items I thought were hard plastic, I spread the drops around with my fingertip until the alcohol evaporated. No effect. On the handset and two caps, the spots with the drops felt sticky.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: jsowers on July 04, 2011, 08:49:10 PM
Quote from: cihensley@aol.com on July 04, 2011, 08:36:30 PM
jsowers:

Thank you. They did sound somewhat different. Based on the fingernail/sound test, I picked the handset and its two caps as being soft plastic, with all of the other components being hard plastic. To resolve any doubt I remembered you saying, in a couple of posts, to never use denature alcohol to clean soft plastic. I put a couple of drops of denatured alcohol on the inside of each plastic component. On the items I thought were hard plastic, I spread the drops around with my fingertip until the alcohol evaporated. No effect. On the handset and two caps, the spots with the drops felt sticky.

CHuck

Exactly--denatured alcohol will melt soft plastic, but what it does to hard plastic is clean off the gunk and evaporate. Hopefully you can find a solution that will work for both, but that will be a challenge on a "combo phone." That's my term for those combinations of hard and soft plastic that resulted when soft plastic was discontinued on the color sets in mid-1959. They looked good when originally assembled, but now you're lucky if the parts still match.
Title: Re: Restoring a WECo Pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 06, 2011, 03:28:38 PM
Quote from: cihensley@aol.com on July 04, 2011, 01:40:49 PM
. . . wiped with methylene chloride and the other half sanded with 1500 grit micro-mesh. . . . The methylene removed the discoloration in about 6 swipes with a saturated rag. . .  the plastic is shinny from the methylene. This suggests that my plan to sand the pink phone then mist it with methylene using an airbrush may work.

Chuck,

Any plans to build a heat controlled hot box to heat the shell to a certain temperature before injecting the methylene chloride into the box at a concentration high enough to reflow the surface plastic uniformly as described in the patent? Also, what precautions are you taking when wiping with DCM - using a vented hood or spray box?


And thanks for the DCM source info. Found out I can get it locally at an industrial chemical supplier.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 06, 2011, 03:48:10 PM
TelePlay:

I may use heat lamps to warm and dry the shell after the methylene is applied. I haven't tested the application yet. I plan to spray the methylene on the shell with an air brush, no box. This trial is to see if this is effective. When I did the wipe test, the only precaution I took was wearing rubber gloves. I know methylene chloride is toxic. When I spray it I may wear a respirator. If you have any ideas on better utilization of the methylene, I am very open to suggestions.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 06, 2011, 03:54:03 PM
Fixing the crack. Strip of plastic blister packaging super glued to shell for crack reinforcement. One of the ribs removed to make the liquid plastic patching material. The crack grooved with a Dremel tool.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: LarryInMichigan on July 06, 2011, 04:17:32 PM
What are you using to dissolve the plastic to fill the crack?  My AE80 shell is ready for the procedure.

Larry
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 06, 2011, 07:55:33 PM
Larry:

A few drops of acetone. I have the small pieces of plastic and the acetone in a small bottle with cap. I let it sit overnight to dissolve fully. It should be the consistency of heavy syrup when it is ready. I am assuming the AE is Tenite or ABS like the WECos. Jorge or someone else may know for sure.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: LarryInMichigan on July 06, 2011, 08:32:00 PM
Chuck,

Do you use pure acetone, or will nail polish remover work?  The AE80 shell I have to fix is tenite.  The later ones were ABS, I believe.

Larry
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 06, 2011, 09:43:27 PM
Larry

I use pure acetone. I get it at the hardware sore. I don't know what is in nail polish remover.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: AE_Collector on July 07, 2011, 01:02:48 AM
Quote from: LarryInMichigan on July 06, 2011, 08:32:00 PM
The AE80 shell I have to fix is tenite.  The later ones were ABS, I believe.

Larry

There are early soft plastic and later hard plastic AE shells. I have always assumed that they were pretty much the same plastic as WECo shells but am not positive about that.

Terry
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: LarryInMichigan on July 07, 2011, 08:34:30 AM
The AE80 shell definitely appears the be the same sort of tenite as the WEs that I have.  The phone was made by Leich, and it has "3-59", which i assume is the manufacture date, stamped on the bottom.  The finger wheel is the early type with the chrome card retainer ring.

Larry
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 07, 2011, 06:57:22 PM
Initial crack repair and repair sanding. A couple of low spots and air pockets to touch-up yet.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: old_phone_man on July 07, 2011, 07:34:47 PM
Very Nice Work!  I'm impressed.  So will you do the same thing to fill the air pockets and low spot?  Do you anticipate needing to Dremel again?
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 07, 2011, 09:00:32 PM
old_phone_man:

Thank you. I doubt if I will use the Dremel again. I may try to liquify the plastic with methylene chloride rather than acetone to see if it dries without the air bubbles.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 07, 2011, 10:29:59 PM
Quote from: cihensley@aol.com on July 07, 2011, 09:00:32 PM
old_phone_man:

Thank you. I doubt if I will use the Dremel again. I may try to liquify the plastic with methylene chloride rather than acetone to see if it dries without the air bubbles.

Chuck

DCM may be the better solvent so I look forward to hear how that works for you. It's not as safe as Acetone but being a more polar chlorinated hydrocarbon closer to the chemical components of ABS than a ketone, it may both dissolve the rib material more homogeneously, preventing bubbles, and bond the paste better to the shell itself. If using DCM as the solvent, it would also make sense to soften the cracked area with DCM as well before applying the paste. I've used Acetone on a rag to clean stuff off of my hands - I would not do that with DCM. Have you tried exposing Blue-Tak to DCM to see if DCM dissolves the Blue-Tak, which would not be good? I'm not set up yet otherwise I'd be experimenting with you on this right now.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 07, 2011, 11:03:55 PM
Teleplay:

No, I have not tested Blu-tack sensitivity to the methylene. I always soften the area to be patched first. That is what I have used the Blu-tack primarily for. To contain the solvent. The use of it is a balance. It contains the solvent. But you have to remove it carefully when the plastic is not fully solidified. Because the touch-up work is not extensive I may forgo the Blu-tack this time. I don't know what "polar chlorinated hydrocarbon" means, but I hope the methylene eliminates the bubbling problem.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 08, 2011, 12:35:31 AM
Sorry, I typed the wrong word. I wrote "It's not as safe as Acetone but being a MORE polar chlorinated hydrocarbon closer to the chemical components of ABS than a ketone" but typed "MORE" instead of "NON" in that DCM is a non polar chlorinated hydrocarbon -  CH2Cl2.

Polar just refers to the dielectric constant of a molecule, it's electrical charge if you will. How it reacts with other chemicals. Water, alcohols and ketones (acetone) are polar and mix with water. The chemicals below are non polar and do not mix with water.

Chlorinated hydrocarbons such a methylene chloride, trichlorethane, perchloroethane and carbon tetrachloride as well as benzene, hexane (rubber cement thinner which works well to remove glues) do not mix with water but work well at mixing with or dissolving similar substances such as plastic, some to greater degrees than others.

Chlorinated solvents (DCM, TCE and PCE) were used as degreasers for years to clean oils and greases off of metal components. Plastics are made from hydrocarbons, crude oil products. The non polar methylene chloride is more similar to the plastic than acetone and as such was probably why WE used DCM to reflow the surface of warm shells.

I have a feeling that while acetone dropped on plastic leaves a rough finish, DCM dropped on plastic may leave a smooth, reflowed finish. Uniform application of DCM would result in a uniform smooth surface - hence the method of misting the warmed shell surface with DCM. If they used acetone, I have a feeling it would just frost the surface, as we all have discovered by getting acetone on plastic by accident.

Once I get set up, I'd like to do some experimenting to see if my feelings are factual.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: jsowers on July 08, 2011, 08:19:00 AM
Wow! Thank you, Mr. Wizard! Seriously, you make me wish I'd taken Chemistry in college rather than Physics.

I have a question or two. Is soft plastic, sometimes called Tenite,  also derived from crude oil products? Isn't it cellulose acetate? More of a "green" product, to use today's vernacular? I wasn't sure, so I thought I'd ask. It would probably behave totally differently under those chemicals if that's the case. So in your tests, be sure to try some of the chemicals on soft plastic if you can. It would be interesting to see a crack repair on soft plastic.

This is a very interesting experiment. Thanks, Chuck and John, for your input on it.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 08, 2011, 11:10:18 AM
Tenite is a cellulose based material made from soft wood. Wood is also a hydrocarbon - carbon based. To make the desired product, they add plasticizers to get the properties they seek. Plasticizers are generally exotic carbon based chemicals and make the final product soft, stiff, flexible, hard at working temperatures. The difference between "soft" and "hard" plastic shells would be the chemical plasticizers added to the ABS before forming. BTW, they even add plasticizers to concrete these days, and have for years. As I think first said in "The Graduate," plastics were the future. It's a very large and wide industrial field. A research chemist working with plastics and a chemical engineer with a plastics specialty would know the many, many details of what used when and what for. BPA is a plasticizer in the news these days. That "new car" smell is plasticizers out gassing from the plastics used to make everything from seat materials to dash boards. So, the scratch and smell test on old shells has merit as does the finger nail tap for hard vs soft plastic. Finally, since the base material for hard or soft plastic is the same, I would expect methylene chloride to work about the same on each. Just a feeling, agian.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 08, 2011, 04:28:02 PM
I placed some plastic chips in a small bottle with methylene chloride for overnight dissolving. It may be my imagination, but the plastic seemed to start dissolving faster than with acetone. TelePlay: I tried some methylene on a piece of Blu-tack and it started dissolving it. I am sanding to remove the bleaching around the embossing on the shell and the handset (see earlier posting in this thread). It sands easily on the soft plastic handset. It is difficult to remove completely on the shell. If you use V30 hydrogen peroxide on any plastic parts check frequently that it is producing desired results. This may mean having to re-coat with V30 several times but you may avoid unintended consequences.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 08, 2011, 06:30:31 PM
Since Blu-Tack held the acetone, that would indicate Blu-Tack is made with non-polar materials and therefore would be very susceptible to being dissolved by the non polar methylene chloride. Just as acetone would dissolve latex spackling paste.

I did a quick test using a piece of 1/8 inch black pebble finish ABS I picked up at Midland Plastic for a dollar. Using DAP latex Spackling Paste (the drywall fixing stuff), I built a circular dam on a corner of the black ABS. I put a little water in the paste so it was somewhat soupy but would hold its form when placed on the plastic. That let the paste fill in the pebble finish beneath it. I then used a hair dryer for a minute or so to dry the surface of the spackling paste dam. I then used a glass eye dropped to fill the dam with DCM. I did it outside. A gust of wind came up and some of the DCM blew onto the dam wall and ran down to the ABS surrounding the dam.

I let it stand until the DCM was fully evaporated, about 2 to 3 minutes at 75 degrees F.

I used a hair dryer again to make sure all of the DCM was evaporated. I then easily removed the still soft spackling paste and washed off the paste in the pebble finish with water.

The DCM did not dissolve the latex based polar spackling paste. The spackling paste seemed to have no affect on the ABS. The center of the dam was now smooth. The ABS outside the dam where the spilled DCM flowed showed signs of reflowing the ABS pebbles.

Seems DCM is a very good chemical to reflow surface plastic and a water based latex paste will do the same thing that Blu-Tack did when using acetone.

Pictures in order of the test are below. The last picture shows the reflowed plastic in the shape of the center of the dam. The area under the paste dam is untouched.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 08, 2011, 06:48:04 PM
TelePlay:

Thank you for the drywall joint filler idea. It will be easier to mold into a dam than Blu-tack. Your test showed that methylene will smooth out a rougher finish than I contemplated.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 08, 2011, 06:50:06 PM
Here is a cropped close up of the last picture after I used a soft bristled brush and water to remove the few bits of spackling paste from within the pebble finish. This closeup shows the reflowed area within the dam and the damage, if you will, to the surface area outside the dam where the DCM was spilled but in lower concentration - just flowed off instead of slowly evaporating about 5 or 6 drops from within the dam. The ABS was tilted slightly with the corner point down so the spilled DCM on top or above the dam remained on the surface longer than that spilled on the lower left which ran off quickly.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 08, 2011, 07:31:46 PM
Chuck

The other side of that black ABS is smooth but with scratches and small nicks similar to what one would find on an abused shell. Being a quick and dirty test to see what affect DCM would have on the latex paste, I decided to go with the pebble finish side as an extreme test. I can imagine what misting DCM on a heated shell will do to reflow the surface as described in that patent paper. I'm still not set up to do time and temperature testing right now but this showed me it won't take much to change a finish. I'm using your air brush application when I get to that stage. What I want to check is not only reflowing the surface to get rid of scratched and dings but also to see what it will take to get rid of fading or darkening with age. I work days so it will be some time before I get to that. I wish they would have included time and temperature in the patent paper. ABS softens around or above 200 degrees F but with the  power of DCM, I'm sure the effective temperature is well below that. Also, if they used a different temperature for hard and soft ABS. Would cut down on the number of experiments to figure that out.

Let us know how using DCM worked with the dissolution of rib material and if any bubbles formed on its application. And, how much faster one must work because of the rapid softening from DCM once applied to the shell.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: TelePlay on July 10, 2011, 08:52:08 PM
Quote from: jsowers on July 08, 2011, 08:19:00 AM
I have a question or two. Is soft plastic, sometimes called Tenite,  also derived from crude oil products? Isn't it cellulose acetate? More of a "green" product, to use today's vernacular? I wasn't sure, so I thought I'd ask. It would probably behave totally differently under those chemicals if that's the case. So in your tests, be sure to try some of the chemicals on soft plastic if you can. It would be interesting to see a crack repair on soft plastic.

Being relatively new to phones and just getting started on resurfacing, I find this forum extremely helpful in providing help and a head start on any project phone related. I've heard hard and soft plastic used quite a lot and found the post by Dennis Markham to be the gold standard of definitions. I also found the 3 links put up by cihensley ( http://tinyurl.com/5trft9v ) excellent. Pages 15-16 of the 3rd document ( http://tinyurl.com/3cnpowa ) lists the chemical mixture for chemical polishing of tenite, soft plastic and the methods used to chemically polish surfaces. They are all polar and less toxic than the methylene chloride (DCM) that works so well on hard plastic (ABS). The question I have is what form of tenite did they use, the acetate or butyrate/proprionate types. What I do see is there is both a chemical difference in tenite vs ABS and the "chemical" of choice for surface refinishing depends on the shell material. We can test soft plastic with DCM and the acetone based mixtures. I'm still waiting for cihensley to post the results of his using DCM to dissolve rib material to fill that crack in his pink phone. To see if bubbles were eliminated and if any other problems developed.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 11, 2011, 04:14:20 PM
Here is the pink 500 with the methylene dissolved plastic covering the defective area. I did decide to roughen the area with with a diamond tip burnishing bit in the Dremel tool. I pre-wet the patch area with methylene before "painting" the liquid plastic. I also placed the patched ares under a heat lamp for 1.5 hours. I will sand tomorrow, and see if there is any problem with air bubbles.

I sanded the side of the white 500 test set (see post earlier in this thread) then used the airbrush to spray it with methylene chloride. The result was not satisfactory. It did shine the plastic somewhat. but I don't think the airbrush produces the volume of methylene needed before it starts drying. Using a regular spray gun would seem to be overkill and would lose a lot methylene in over spray. I will try a Prevel sprayer. The WECo patent calls for 30-50% trichloroethane to be added to the methylene. This missing ingredient may help, but unfortunately is very difficult to get. It manufacture was outlawed in the late '90s because the government implicated it in ozone depletion. I found a couple of sites that list it but they said they were out of stock and may not have more for several months. There were several Chinese companies that listed it as available but required ordering in "rail car" quantity. I will try to determine if there is a substitute for trichloroetane.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: Bill on July 18, 2011, 10:18:56 AM
Quick question for our resident chemist - could (should) MEK play a part in any of this? Methyl ethyl ketone used to be common in electronics shops and production facilities because it would clean excess solder flux off joints very quickly, and then was itself easily cleaned off the joint. It is still readily available locally and inexpensively. It is water-soluble, which would aid cleanup, and is used for solvent-bonding some plastics (polystyrene? others?)

Bill
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 18, 2011, 12:32:42 PM
Bill:

Yes, it will. I am still experimenting with filling the crack. I still got air bubbles when I used methylene. Although it is close to acetone (which also caused air bubbles) I plan to try the technique with MEK. With acetone or methylene it is possible to eliminate visible air bubble with repeated applications of the dissolved plastic. But microscopic air bubbles remain. Although they are not obvious, their effect is to lighten the crack patch so it doesn't totally blend-in with the surrounding area. A solution is to use a mold making vacuum chamber on the liquid plastic before applying it. But these cost $400-$600 so are not a practical solution.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 20, 2011, 01:25:33 PM
While I continue experimenting to find a magic elixir to fix better a crack in hard plastic, I restored the handset cord. See the first picture in this post for a before. I cleaned the cord using the jsowers method and then dyed it according to the directions post by Dan/Panther about two years ago.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 25, 2011, 06:24:41 PM
An update. All three solvents (methylene chloride, acetone and MEK) produce bubbles in hard plastic patches (I didn't have the same problems with the 500Us I restored). The bubbles are formed by the evaporation of the solvent in the dissolved liquid plastic. I tried a new technique that seems promising. Instead of using a solvent to dissolve plastic chip (from reinforcing ribs inside the phone) in a small bottle, I wet the area to be patched with solvent using a small brush and wet an area (with a 1 to 11/2" natural bristle brush) between two ribs on the inside of the phone. The wetting with solvent makes the plastic soft. I then used the side of a box cutter blade (I dulled the cutting part of the blade before I used it) to scrape some soft plastic from the area that I wet inside the phone. I then buttered the plastic into the crack grove. It appears that less solvent is in the plastic this way - therefore no bubble problem. In the picture of the pink shell you can see the patched area with the old and new techniques. Without the gas bubbles the fill color better matches the rest of the shell. I will now "Dremel tool-out" the old fill and patch with new fill. I used MEK for this patching because it has the lowest vapor pressure of the three solvents.

I have not had any success with solvent polishing like described in WECo's patent. I tried a Preval sprayer rather than the airbrush to get more volume. The Preval produced some gloss if I got a particular area very wet. But this would produce runs in areas I wasn't spraying. I believe the WECo method sprayed a much higher volume of solvent on all parts of the plastic at the same time. Any ideas on how to do this? Also I have been unable to find a source for 1,1,1 trichloroethane which WECo mixed with their methylene chloride.

The picture of the blue shell shows the ability of the solvent (MEK in this case) to remove discoloration. The discoloration was removed by a cheap 11/2" natural bristle brush in about three swipes. Using a good quality brush should result in fewer brush stroke marks.

The picture of the white shell shows discoloration removed by MEK then sanded to remove the brush marks.

Using solvent to remove discoloration seems to promise a quicker way to restore then just sanding alone.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 29, 2011, 07:29:06 PM
Patch completed and sanded. The new technique for softening plastic for patching (see above) seems to work. A slight amount of ghosting where the patch is. I guess the solvent changes the crystalline  characteristics of the plastic.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 29, 2011, 07:31:34 PM
The picture I meant to include with the last post.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: Dennis Markham on July 29, 2011, 08:11:06 PM
Chuck.........Wow!  Fantastic repair and restoration of that Pink 500 housing!
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on July 30, 2011, 03:21:30 PM
Further experimenting. I sanded the caps with all grits of micro-mesh then sprayed them with MEK. I used a Preval sprayer and more than dusted with MEK. I got them wet but not to point that there was a danger of runs. These were not buffed. The MEK seemed to eliminate the fine scratches remaining after the 12000 grit micro-mesh, thereby imparting a gloss to the surface.

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: old_stuff_hound on July 30, 2011, 03:38:31 PM
Quote from: cihensley@aol.com on July 30, 2011, 03:21:30 PM
Further experimenting. I sanded the caps with all grits of micro-mesh then sprayed them with MEK. I used a Preval sprayer and more than dusted with MEK. I got them wet but not to point that there was a danger of runs. These were not buffed. The MEK seemed to eliminate the fine scratches remaining after the 12000 grit micro-mesh, thereby imparting a gloss to the surface.

Chuck

Looks great! That's impressive work!

That was the idea in the patent wasn't it -- chemically polishing the surface? I wonder if that's why you were having troubles with bubbling -- the solvent being deeper in the plastic when welding the cracks than it would be if just used to level the surface.

Any idea if WE ever used their process in a production environment?

Now I wanna see the completed phone! :-)

Cheers!
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: cihensley@aol.com on August 05, 2011, 04:02:35 PM
Here is the completed phone. Verified by the denatured alcohol test, the handset and its caps are soft plastic. The balance of the plastic components are hard plastic. Overall, I am pleased with the MEK polishing. It produced a gloss and depth that I haven't achieved with polishing (buffing) alone following micro-mesh sanding. The MEK finish had a slight matte appearance. This is perhaps due to my conservative spraying to avoid runs. Buffing with Novus 2 eliminated most of the matte appearance. I was not able to eliminate all of the bleaching in the embossing and surrounding area from the V30 hair creme (see post earlier in this thread). To totally eliminate it would have involved an inordinate amount of material removal.

I set out to use WECo's patented process for restoring hard plastic. I concluded that I don't have the ability (through spraying) to deliver the volume of solvent necessary to wash away discoloration and leave a shiny new surface. It appears that the best that can be done is to use solvent to remove discoloration (with brushes and rags), followed by micro-mesh sanding to remove the marks of discoloration removal, followed by solvent polishing. The effectiveness of the latter was shown in the work on this phone. My next restoral will test the front end of the process.

The use of solvent softened plastic for crack repair has not been completely effective. Small gas bubbles mar the finished appearance. I continue to experiment with various techniques on old shells.

I offer the product of this test for $10 plus $10.50 USPS flat rate medium box shipping. If interested, send me an email at: cihensley@aol.com

Chuck
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: old_phone_man on August 05, 2011, 06:37:10 PM
Good Looking Work!!
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: rtp129495 on November 18, 2011, 07:43:35 AM
I hope I can make my no dial Pink 500 that way. Its currently painted black badly. But awesome job I like that. Is it wierd for a guy to like a pink phone? lol.
Title: Re: Restoring a WECo pink 500 Set - Sanding and Solvent
Post by: suhoni56 on October 29, 2014, 05:15:39 PM
Great job; thanks for sharing! I am going to keep reading before I begin. I have 3 project phones awaiting my efforts.

And no, it is not weird for a guy to like pink phones. It is weird that humans decided that pink is feminine.