TN Frankfurt shell repair

[countryman]

Last month I found this smashed "Frankfurt" (sometimes titled the Bauhaus phone) for cheap in a lot. Since I already have a Frankfurt, but a version with a DC buzzer instead of a ringer, I thought the innards might come in handy.
Having the piece in hand, I decided to attempt a restoration/repair/amendment.
I can see the extensive use of non original materials and and unconventional techniques is more a replication than a restoration. Judge for yourself.

In the first step I used a plaster bandage on the good shell to create a mold. It's the same material a doctor uses on broken arms... a thin mold is astonishingly rigid when cured.
The mold was moved to the broken shell then.
I filled in the missing parts with Milliput putty. I rolled out the putty between plastic sheets like cookie dough, put it into the mold and cut off the overlapping parts. The interior side is quite rough and will remain this way, as sanding it would be hard and bear a risk to break everything.
The last picture shows the outside after coarsely sanding it and filling in some small remaining cavities with more Milliput. I will now fine sand the reproduced parts. Unfortunately, "black" Milliput isn't actually black, but gray when sanded. I will try a plastic dye for automotive parts to get it darker.

[RDPipes]

Great job sir, looking good, can't wait to see it finished.
I know what you mean by it isn't real black but, I find that if I cheat a bit on the mixing and
use a little more black putty then white I can get it black and it doesn't seem to affect its strength in the end.
YMMV

[countryman]

Done. The repair is visible but seems acceptable to me. Filling and painting the whole deal would be the alternative.
Cords still have to be made.

[RDPipes]

Looks great considering the damage that had been done, I don't reckon I could have done any better.

[FABphones]

I had noticed that since I first started using it Milliput seems to have lost much of its black pigment.

The repair has come out really well. Black auto polish will help a little to remove the greyness but it may take a few coats.

Something I was toying with until recent events was the use of fabric dyes. Also black ink dyes.

(Test on the inside areas first).

[RDPipes]

I had noticed that since I first started using it Milliput seems to have lost much of its black pigment.

The repair has come out really well. Black auto polish will help a little to remove the greyness but it may take a few coats.

Something I was toying with until recent events was the use of fabric dyes. Also black ink dyes.

(Test on the inside areas first).

Yes, I believe an alcohol base dye like leather dyes will penetrate better but YMMV.

[countryman]

This is the product I used:
https://www.sonax.co.uk/shop/exterior/rubber-plastic-trim/trim-plastic/sonax-plastic-restorer-black-100ml/
The advertised price is higher than what I paid locally (in Euro currency).
I originally bought it for the top case of an Italian Vespa motor scooter and was pleased with the result.
It resembles shoe polish and comes in a similar package with an application sponge, but the effect is much stronger and it is permanent.

[countryman]

I know what you mean by it isn't real black but, I find that if I cheat a bit on the mixing and
use a little more black putty then white I can get it black and it doesn't seem to affect its strength in the end.

Thanks for the hint, I'll try it next time!
Another Milliput cheat I discovered, if you mixed too much material by accident you can prevent  hardening by freezing it
At least I found it was unchanged a week later and behaved normally after thawing.

[RDPipes]

Thanks for the hint, I'll try it next time!
Another Milliput cheat I discovered, if you mixed too much material by accident you can prevent  hardening by freezing it
At least I found it was unchanged a week later and behaved normally after thawing.

Sounds good, I'll try that next time I mix up too much. I usually end up with a ball the size of a marble left so
if freezing keeps it from hardening after several mixes I might have enough to do another project without mixing, sure worth the try.
Thank you CM!

[TelePlay]

Low priced resin dyes can be used to turn the dark grey Milliput black - a small drop of black resin dye well mixed into the putty when activating it gets rid of the grey.

A google search for "black resin dye" results in many sources, attached is the code Aluminite product for example.