The roof vents on one of my engine houses have taken a beating over the years and I've decided to replace them. One of the problems is they are too tall and prone to getting knocked off with a clumsy elbow. I thought it would be better to replace them with a lower profile vent. I went to my drawer of spare lead castings that I have accumulated from other projects over many years. I found a perfect replacement both size wise and the fact they perfectly match the pitch of the roof. The problem is I could only find three and I need four.
I got the idea to try fabricate a fourth vent from the existing vents but I have never tried such a thing. I was thinking of pressing the existing vents into some modeling clay to make molds, pressing both a left half and right half. I could then fill them with a substance that would harden, then glue the two halves together and paint them to match the existing ones.
I'm wondering if there is a better material for making the mold than modeling clay. The two materials I'm thinking of using to fill the molds are either plaster of paris or casting resin. Is there a better choice than those?
Check out Alumilite products. Many of them are available at Hobby Lobby.
Dave H. Painted side goes up. My website : wnbranch.com
an alternate to turbine style roof vents could be to get round burs for tools like dremels. there is one made that is round except the shaft.
dehusman Check out Alumilite products. Many of them are available at Hobby Lobby.
Rich
Alton Junction
Most of the Alumilite products I looked at on Amazon look like they are similar to Famowood Glaze Coat which is also a 2 part resin product and which I also have a small amount left over from using it on water features on the layout. If this type of product is the best choice to make the vents, the question then becomes what to make the molds from. In searching for Alumilite on Amazon, this product also was listed:
Environmental Technology 1/2-Pound Kit Casting' Craft Easymold Silicone Putty : Arts, Crafts & Sewing (amazon.com)
That looks like it would easy to work with although a bit pricey just to fabricate one small part. I could probably vacuum seal it and use it later if another need arises.
Alumilite makes a 2-part kit. The mold is formed over the part to be cast. Then, the casting material is poured into the mold.
richhotrain Alumilite makes a 2-part kit. The mold is formed over the part to be cast. Then, the casting material is poured into the mold. Rich
https://www.alumilite.com/silicones/amazing-mold-rubber-3-4-lb/
The resin mix is then poured into the rubber mold to cast the needed part or parts.