duplicating window castings

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Benjamin Maggi
Posts: 1193
Joined: Wed Apr 25, 2007 10:38 pm
Location: Albany, NY

duplicating window castings

Post by Benjamin Maggi » Mon May 06, 2019 11:26 am

I purchased some window casting from a fellow member here on Chaski over the winter. They are nearly perfect for what I need, and I have the exact amount I need. But, neither he nor I have any idea who made the castings. They don't match anything on the market today. I am concerned that if I damage one I will be in a real jam.

Is there an easy way to make a copy of the casting (rubber mold, plaster mold, etc?) so that if I ever need more I can make them from resin or something?
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"

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SPSteam2491
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Joined: Tue Feb 21, 2017 2:30 pm
Location: Mukwonago, WI

Re: duplicating window castings

Post by SPSteam2491 » Mon May 06, 2019 11:37 am

Check out some of the products Smooth On makes: https://www.smooth-on.com/. There are other companies out there that make similar products as well.

Depending on the complexity of the casting, it could be an easy project to 3D model then you could send it to Shapeways or any other 3D printing services to reproduce the part as you need. Really once you have the 3D model, the part will never become extinct as long as you keep the file.
Thanks
John LaFavor
Pacific Design Shops

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Benjamin Maggi
Posts: 1193
Joined: Wed Apr 25, 2007 10:38 pm
Location: Albany, NY

Re: duplicating window castings

Post by Benjamin Maggi » Mon May 06, 2019 1:23 pm

Would I just mail the casting to a 3D company and have them scan it with a 3D scanner?
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"

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SPSteam2491
Posts: 110
Joined: Tue Feb 21, 2017 2:30 pm
Location: Mukwonago, WI

Re: duplicating window castings

Post by SPSteam2491 » Mon May 06, 2019 1:39 pm

PM Sent
Thanks
John LaFavor
Pacific Design Shops

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Dick_Morris
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Joined: Sat Jan 04, 2003 2:09 pm
Location: Anchorage, AK

Re: duplicating window castings

Post by Dick_Morris » Mon May 06, 2019 10:35 pm

There are some good Youtube videos using Alumilite. I've used it and it worked pretty well and wasn't hard to use. The down sides are that it works best when you can vacuum the material and the material has a limited shelf life - I think a year of so.

Another option would be to use some Petrobond sand and cast duplicates in one of the zinc alloys. I've used ZA-27 and it is easy to cast and machine. Pouring temperature is around 750 degrees and it can be melted in a small, cheap stainless steel pan with a propane torch for heat. The originals should have some draft so could be used as a pattern. A possible downside is that you will get a little bit of shrinkage compared to the original.

I had those window frames 20 years or more. The person I got them from probably had them for several years and I think he got them from someone else. I wouldn't be surprised if they were upwards of 40 years old.

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Benjamin Maggi
Posts: 1193
Joined: Wed Apr 25, 2007 10:38 pm
Location: Albany, NY

Re: duplicating window castings

Post by Benjamin Maggi » Wed May 08, 2019 9:37 am

Thanks Dick!
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"

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