Ivory GPO 232 from Spares - Resin Repair

[FABphones]

I found enough parts in the spares boxes to make an Ivory GPO 232. Two sections had damage so this was another opportunity to get some resin and pigment practice in.


Photo 1: Damage to cable exit at rear of body shell. This looked to be a deliberate cut (I've seen this done before and I haven't a clue why).

Photo 2: Cable exit damage filled with epoxy resin, partially sanded.

Photo 3: Damage to cradle, chunk broken away. Filled with epoxy resin and partially sanded.


I have sampled three manufacturers resins. In my experience, standard shop bought resin has failed to give a good enough adherence every time.

To do this better a vacuum chamber is required. Fine air bubbles can be seen in the resin.

Pigment will dry a different shade. Let it dry then select a colour match.

Each Bakelite section will need a different resin shade to match in.

Change the light; on these examples the pigment match was fine in the evening. As you can see from the first two photo comparisons, another day, another light.....

[FABphones]

Same areas after finer sanding. For these two photos I tried to get in close with the camera to show the repair and colour match up close.

[RB]

very nice

[FABphones]

very nice

Thanks RB. 

This phone was in many parts, just about everything had to be found and pieced together, from the drawer front to the inner screws. In my box of cables I found an NOS handset cord, and in my dial box an original Dial Card which looks fine on this phone. The base is marked CB so it all turned out to be a decent match.

This morning was spent sanding, shining and assembling. I finished the phone this afternoon, just in time to test out the new but very cheap photo light cube kit. I still need to work out where to put the lights, the cable shows up as darker than it is, and the phone shows up slightly whiter on one corner but the ivory is pretty even throughout.

.......I forgot to take a photo of the rear.......

[Scott]

Nicely done!

Scott K.

[.....]

I have to give it to you Fab, you have did a fabulous job on that phone. LOL

Another phone pulled from the junk and brought back to life!

To tell the truth I'm taking a liking to the British phones. 

[Pourme]

~

You did it again, Fab.....You have become quite the accomplished phone whisperer!

[FABphones]

You did it again, Fab.....You have become quite the accomplished phone whisperer!

You are all very kind. I'm getting there!
This project threw up lots of questions (some of which I think I may have the answer to, ready for the next one).

Photo of the rear added, which I forgot to take yesterday. This pic taken under natural light:

[FABphones]

Same 232 phone, pictured here next to a very small model of the Post Office Tower (London, UK).

Since  this rebuild I have discovered that small amounts of resin can be warmed on a Heat Mat to help remove air bubbles. This can however shorten the resin work time.

 

[RDPipes]

Another Grand job CJ, these ivory phones are just gorgeous.

[kleenax]

To do this better a vacuum chamber is required. Fine air bubbles can be seen in the resin....

Actually, a pressure chamber will work better to rid your resin of bubbles. I have 4 that I use daily, and pressurize my resin castings @ 80psi for best results. You can get one of the smaller, 2 to 3 gallon sizes that are ordinarily utilized for pressurized painting applications. Just make sure that you secure one large enough to get your part(s) in! 

[FABphones]

Actually, a pressure chamber will work better to rid your resin of bubbles...

I have a pressure tank (10 gallon) and a vacuum chamber, the issue with this repair was working with such small quantities of resin. The repair for each of the two parts of this phone used less than 1/2 teaspoon. How best to remove the air bubbles from quantities as small as that?

As always, trial and error and lots to learn.
 

[kleenax]

I have a pressure tank (10 gallon) and a vacuum chamber, the issue with this repair was working with such small quantities of resin. The repair for each of the two parts of this phone used less than 1/2 teaspoon. How best to remove the air bubbles from quantities as small as that?

As always, trial and error and lots to learn.
 

For sure on the "trial & error"; I have about 20 yrs of that now ;-)

What I do when I have a small repair like that, is to actually place the phone body that is to be repaired into the pressure pot first, and then I apply the needed resin. I also try to put a little more than necessary as you can always trim it once it has cured. Sounds like you have it covered though.

The trouble with using the vacuum chamber for a repair like this, is that when under vacuum, the liquid resin will usually bubble-up and overflow and cause a ruined repair.

[FABphones]

...place the phone body that is to be repaired into the pressure pot first, and then I apply the needed resin...

Thanks for that.

My method is to use the vacuum chamber to degas prior to application. I have never placed anything premade (eg Bakelite, Diakon) into a pressure pot.

Sounds like I have more experimentation fun ahead.

...I have 4 that I use daily...

What size (gallon) are your 4 pressure chambers?

[kleenax]

Thanks for that.
What size (gallon) are your 4 pressure chambers?

I actually have -8- pressure pots. The largest is 60 gallons. I needed it for several "special" projects that were huge. I also have a 40-gallon, a 15-gallon, and the rest being 10 and 5 gallon capacities. I also have 2 or 3 extras at any given time that I sell to interested buyers. Additionally, I have 2 vacuum ovens (used primarily as vacuum chambers), and 4 or 5 high-vacuum pumps, some as high volume as 23CFM; I refurb & sell these too. Lastly, have 2 industrial convection ovens that are run 24/7 at 150 degrees F for curing resin and heating the molds prior to casting water-clear resins. Most all of this equipment was sourced "dirt-cheap" at a local university's surplus store!