Author Topic: Reproducing parts using Milliput epoxy putty  (Read 2691 times)

Offline countryman

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Reproducing parts using Milliput epoxy putty
« on: June 07, 2020, 07:23:13 AM »
After good experiences with Bakelite repairs I tried to manufacture missing parts using Milliput.
The parts missing are always the same: Those that are prone to break or that are easily detachable and get lost. To replace them means buying the same phone or handset twice, because they are unavailable as a separate item.
For phones of lesser economic or collectible value reproduced parts may seem acceptable. As I neither have a 3D printer nor the knowledge to generate a CAD file I went ahead and tried this analogue method.

First item is a Bakelite repair of a Siemens & Halske transmitter cap. The putty was hand formed right on the handset. I used vaseline to avoid sticking on the handset body and thread.

Second item is the receiver cap of a German OB05 handset. I had the metal rings, but not the actual cap, originally made either from Bakelite or Ebonite. I made a plaster mold from an existing cap.

Offline countryman

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Re: Reproducing parts using Milliput epoxy putty
« Reply #1 on: June 07, 2020, 07:38:26 AM »
Third is the receiver cap of a French wooden desk phone of unknown origin. Such handsets are available - in France. Postage alone would be half of the value of the entire phone. Again, I made a plaster mold of an existing cap. I rolled out a wafer of Milliput, just like cookie dough, and formed it against the mold. So I had a cup with the proper shape on the outside. I let it cure and in a second pass I put in the original male threaded part and filled the gap with Milliput. This time I used silicone oil as a separating agent. After the putty started to set a little I carefully unscrewed the male thread. As I had hoped for, the thread works just fine after hardening, although it is a very fine pitch.

The part has visible signs of the hand forming, but hey, it's an old phone  8)
« Last Edit: June 07, 2020, 07:47:09 AM by countryman »

Offline Doug Rose

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Re: Reproducing parts using Milliput epoxy putty
« Reply #2 on: June 07, 2020, 08:09:54 AM »
that is amazing! Really nice job....Doug
Kidphone

Offline RB

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Re: Reproducing parts using Milliput epoxy putty
« Reply #3 on: June 07, 2020, 09:00:38 AM »
"Hey", nothing...Countryman,
That's a wonderful job. Couldn't reuse "amazing", Doug already had that. lol
The threads have my head spinnin! :o
You hit it square. ;D
Very impressed!
I have made some repairs outa epoxy, but never tried threads. 3 thumbs up!
For those wondering, I'm not wearing shoes ;)

Offline Scott

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Re: Reproducing parts using Milliput epoxy putty
« Reply #4 on: June 07, 2020, 09:34:04 AM »
That turned out great. I am impressed.

Scott K.

Offline .....

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Re: Reproducing parts using Milliput epoxy putty
« Reply #5 on: June 07, 2020, 09:45:29 PM »
Great idea, I'm going to have to give that trick a try.

Offline countryman

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Re: Reproducing parts using Milliput epoxy putty
« Reply #6 on: June 08, 2020, 03:38:50 AM »
Thanks a lot for the appreciation!

Offline FABphones

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Re: Reproducing parts using Milliput epoxy putty
« Reply #7 on: June 08, 2020, 04:11:43 AM »
Those all came out really good. I often find it can be difficult to get a good mold from plaster, so you did extra well there.  :)
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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Offline countryman

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Re: Reproducing parts using Milliput epoxy putty
« Reply #8 on: June 08, 2020, 07:23:02 AM »
I used regular plaster from a building supply store, a quick setting type used by electricians to fix cables and boxes to walls.
The problem with plaster is that it is rigid and does not allow any undercut (hope the word is correct?).  I used vaseline on the model objects to separate them from the plaster when hard.
Of course there are better molding materials, like silicone. But these are more cost intensive, too. Using them would allow to make small series of reproduction items from liquid epoxy with the right tools and practice.

Offline markosjal

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Re: Reproducing parts using Milliput epoxy putty
« Reply #9 on: December 27, 2020, 05:13:56 AM »
I just posted how I used this same product to repair a broken Leitch housing

More pics here too:
http://www.classicrotaryphones.com/forum/index.php?topic=24683.0
« Last Edit: December 27, 2020, 03:12:39 PM by markosjal »
Phat Phantom's phreaking phone phettish