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Building from Spares: GPO 232 King Pyramid

Started by FABphones, February 10, 2019, 02:12:22 PM

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FABphones

Ok... Mixed results with the resin repair on the body damage. Photo below shows what it looks like mid sand.

Today I began the buffing process and as you would expect, once a shine is on the surface the repair shows more than I would have liked.
A collector of  'Monochrome Phones with Sepia Tones'   ...and a Duck!
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andy1702

Now you've sanded it the repaired crack still looks a bit low to me. Is that right? I think I'd try putting more resin in and leaving it a bit proud of the surface, then sand the excess off. The other option would be to give it a coat of filling primer then paint the whole phone. Painting isn't ideal, but as the case was damaged anyway I'd view it as a necessary repair if that's the only way to get rid of the crack. You could always paint it red, then you could sell it on fleabay and buy about 10 more black ones with the profit!  ;D

Seriously though... I tried a similar repair using epoxy resin with powdered charcoal mixed with it for pigment. The problem I had was bubbles in the epoxy which only came to light once I started sanding it.

Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.

FABphones

#17
An update on progress so far:

Mixed results on this first try, I definitely need more practice. The resin didn't quite give a good enough (in my opinion) 'invisible' repair. It may be too low, but I'm not sure that's totally it. I think the break was a smidge out of alignment too. Judging by the corrosion, it had been left like that quite some time before it came to me. The plunger is also out of alignment so I need to address that as well before it can be reassembled.

Another thing I discovered, is working with such tiny quantities of resin makes it tricky getting the pigment quantity correct (it would be much simpler to mix up a vat of the stuff ;D). I used jewellers scales but even so, one drop of pigment weighs more than one might think.

I have also experimented by adding additional resin to the exterior, but it does not adhere well enough without heavy sanding (I try to keep sanding of Bakelite to a minimum due to its construction. Usually I don't sand it at all). Internally I would have also added fibre-glass sheeting for extra strength but I never had any. Noted for next time.

I don't paint Bakelite as it is not to my liking but if the final result isn't great no harm done, an undamaged body will turn up at some point and I can replace it. Meantime I've got some practice in and shared the result, good or bad. And regardless of how it turns out, I have learnt from this and will move forward with that knowledge.  :)

As the #10 dial I initially selected has now been earmarked for another project, I used this #12 dial. It needed a little attention (black gloss paint spillage to one side, fingerwheel didn't return correctly). Cleaned, oiled, now whirring nicely.

Photo of dial rear numbering, and photo of repaired area now buffed, with dial in place. Damage shows up differently according to the angle viewed and the light on it.

Still lots of work left to do on this phone.


A collector of  'Monochrome Phones with Sepia Tones'   ...and a Duck!
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Vintage Phones - 10% man made, 90% Tribble
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FABphones

Today has been a good day.  :D

Firstly I managed to get the plunger working again. Seized into position, over time it had distorted out of shape and once freed wouldn't fit correctly into it's cradle.

Thread for the fix here:
http://www.classicrotaryphones.com/forum/index.php?topic=22014

Then I continued sanding the break and got that looking a bit better too.

And finally I removed the paint from the Bakelite junction box that I will be using for the line cord. Gave it the shiny treatment and it shone up beautifully. Very pleased with that - shown in photo with no lights turned on, and it's not wet.     ...Sunglasses on  8)
A collector of  'Monochrome Phones with Sepia Tones'   ...and a Duck!
***********
Vintage Phones - 10% man made, 90% Tribble
*************

andy1702

Have you tried black boot polish on that crack? It needs to be the traditional thick waxy stuff in a little round tin. Apply liberally, wipe off the excess with a cloth then buff with another cloth to a shine. If the crack is a bit low the polish should fill it in.

I have some bakelite repairs to do myself, but my problem isn't cracks, it's missing chunks. I've been putting it off for ages, prefering to work on ABS cases where I've got a bit of a system going.
Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.

FABphones

#20
Quote from: andy1702 on February 28, 2019, 03:26:03 PM
Have you tried black boot polish on that crack? It needs to be the traditional thick waxy stuff in a little round tin. Apply liberally, wipe off the excess with a cloth then buff with another cloth to a shine. If the crack is a bit low the polish should fill it in.

Thanks for the suggestion. Out of curiosity I had already tried that a few days ago. Ineffective, but knowing what doesn't work is almost as good as knowing what will.

The damage repair isn't quite what it appears to be in the photo, there is no gap to force anything into. It's a fraction of a mm height difference between the two levels. I'm cautiously working on the difference with micromesh, although sanding Bakelite isn't something I like to do.

The correct way to continue with this would be to remove all resin and start over, however I doubt I could now get a good bond inside that fracture without opening it up and grinding it. And if I tried that, in this instance it would probably do more harm than good.

*Chunks are a doddle in comparison!  :)



A collector of  'Monochrome Phones with Sepia Tones'   ...and a Duck!
***********
Vintage Phones - 10% man made, 90% Tribble
*************

andy1702

I'm curious what resin you're using? The colour match and finish looks really good. Like you said, it's the height difference that's making the joint show.

The way I understand it, bakelite is a sawdust filler suspended in some type of resin. It's certainly grainy under the surface. My assumption is the resin flows round the particles of filler to reach where the bakelite interfaces with the mold. So what I'm wondering is if you can take the surface off a relatively large area and re-flow a thin layer of resin over it? I've not tried this, it's just an idea in my head.
Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.

FABphones

Here it is folks. Finished.

The damage to the corner is stable and strengthened from the inside. Not as invisible as I would have liked, but I've learnt a lot from this first resin project.

These many discarded parts are now a complete telephone again, pieces out of spares boxes that I have accumulated over time, from all areas of the UK. Odds and ends, from the spitcup to the dialcard circlip.

It threw me a few curveballs but I got there in the end.  :)
A collector of  'Monochrome Phones with Sepia Tones'   ...and a Duck!
***********
Vintage Phones - 10% man made, 90% Tribble
*************

FABphones

Thanks guys, you are very kind.

As I get more experienced with these resins I may come back to this one, but at least I managed to find all PL (Plessey) parts so it's about as 'parts matched' as these come.  :)
A collector of  'Monochrome Phones with Sepia Tones'   ...and a Duck!
***********
Vintage Phones - 10% man made, 90% Tribble
*************