Replicating (dogbone) resistors what method have you used ? - Printable Version
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+--- Thread: Replicating (dogbone) resistors what method have you used ? (/showthread.php?tid=22131)
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RE: Replicating (dogbone) resistors what method have you used ? - John Bartley - 11-15-2021
Richard,
This Alumilite appears to be similar to (maybe supplied by?) the product and process sold by Dow Corning. About fifteen years ago I tried the D-C molding materials and had very good success with them. The give clean smooth surfaces, flow well into details and if you use the correct compatible products as per the instructions, they perform as advertised.
One note :: when I was trying it, the Dow product I was using recommended a vacuum evacuation of air just prior to pouring. It increased the density and strength without compromising the flexibility. I don't see that (unless I missed it) in the Alumilite instructions or spec's.
cheers, good luck and have fun !!
EDIT :: the shelf life on the D-C raw product was very short (a year or so as I recall), so buy the smallest amounts that are economical for your purpose, and be ready to use it.
RE: Replicating (dogbone) resistors what method have you used ? - radiorich - 10-06-2023
hello Everyone,
Well it is time to start making some resistors !
My latest Philco 38-10T needs some made one is a 3 watt 10 k power resistor .
Sincerely Richard
RE: Replicating (dogbone) resistors what method have you used ? - radiorich - 11-08-2023
Hello Guys,
Well this year is time to final make these resistors because I also have to make some for my Philco 38-10T they are easier then the Zenith !
Sincerely Richard
P.S. I have a week off of work during the week of thanksgiving so in the next few days I will be ordering molding supplies .
RE: Replicating (dogbone) resistors what method have you used ? - radiorich - 01-25-2024
Hello Everyone ,
Rockler had a sale on Amazing mold maker and Amazing Casting resin
By Alumilite So I ordered those two items to see how they work .
there is also a knob for my 1950s GE clock radio I want to try casting too.
The Resin says it's good for 185 Degrees
Sincerely Richard
RE: Replicating (dogbone) resistors what method have you used ? - radiorich - 10-10-2024
Hello guys,
I have a question has anyone tried using off the shelf Pematex sensor save RTV to make a mold like the one Russ posted to make my dog bone resistors ?
Sincerely Richard
RE: Replicating (dogbone) resistors what method have you used ? - DaleHCook - 10-12-2024
RTV is flexible. For dog bone replacements you want a rigid material such as epoxy.
RE: Replicating (dogbone) resistors what method have you used ? - Eliot Ness - 10-13-2024
Richard,
The RTV might work for the molds, but it might be too soft, I haven't worked with gasket maker in a few years. The newest idea I have run across is making the shells on a 3D printer. Below is the work of someone else, not myself:
I believe he made his on a resin printer. I printed some off with plain old PLA filament, but for heat resistance PETG or maybe ABS would probably be best. I have some STL files if you're interested. The third picture is an enlargement I made in TinkerCad.
RE: Replicating (dogbone) resistors what method have you used ? - radiorich - 10-15-2024
Hello Dale,
I am talking about using the RTV as the mold.
Well John, yes, I have seen that design I think it was one of the ARF forum members he sent me that file.
I really want a 3D printer to use at my home and found one that I really want Prusa MK4S but it's over a grand see I want fully enclosed one we use a Flasforge brand in the classroom at the school I have been using one for over 5 years .
John did you see the domino style capacitors that he made too.
Sincerely Richard
RE: Replicating (dogbone) resistors what method have you used ? - Eliot Ness - 10-15-2024
Quote:John did you see the domino style capacitors that he made too.
No, I did not see those Richard. I'll have to try and find it over there.
RE: Replicating (dogbone) resistors what method have you used ? - radiorich - 10-15-2024
Hello John,
I can look for the file and email it to you too.
Sincerely Richard