Casting Mold Volume

[eharri446]

I order one each of the Junior, Sierra, and Patriot series molds from pTownSubbie and was wondering if anyone who uses these molds can tell me what the volume of ALUMILITE is for each mold.

I have reached out to the supplier, however, I thought it might be faster to ask the membership the same question.

Thanks for any repsonse.

 

[whsewardiv]

to get a quick idea of how much casting material to use, put the tube in the mold with the plugs and fill it water, then divide the volume of water by the ratio of the casting material. for example if I'm using Alumilite Clear which is a 1:1 mix, then divide the amount of water you put in the mold in half. 4oz of water=2oz of part A + 2oz of part B.

this is just a rough idea, this is all about trial and error, keep a log of how much you use for each mold and adjust accordingly for the next batch
I hope this helps

 

[lhowell]

I use Alumilite for my Sierra PTownSubbie mold and usually mix 1.5oz total (0.75 oz A side and 0.75 oz B side) and usually have a tiny bit left after I pour the mold full.

You can do a simple volume calculation by measuring the mold cavity (dont worry about the bottom being curved, just treat it like a rectangle using the deepest part of the mold for your depth measurement).

Alumilite also has a great calculator on their website to figure out exactly how much you will need by typing in the dimensions in the correct field as there are fields for silicone to make molds, mold cavities, etc. Just remember that if you use this calculator page that the final answer is both A and B side combined so you will need to divide by 2 to get the individual amounts of A and B resin parts.

Volume Calculator

 

[bkersten]

When I use PR in PTowns Sierra 2 cavity mold it takes 3/4 oz per side or 1.5 oz for the 2 blanks. That is filled up level to the top, but I go higher due to the shrinking of the PR. Very little waste left over, for me anyhow.

 

[BSea]

Here is the volume calculator from Alumilite. https://www.alumilite.com/store/pg/12-Volume-Calculator.aspx Although this may not help much for tube in casting.

I respectfully disagree with whsewardiv on his method. Alumilite is measured by weight not volume. Part B is heavier than Part A. While you can probably get by with his method, If you plan on casting long term, then I'd suggest you buy a digital postage scale that measures in grams as well as ounces. I use ounces when I cast PR, and grams when I cast alumilite

 

[crabcreekind]

1)Weigh you empty molds, measure them in grams or oz.
2)Fill your molds with water, measure them in grams or oz.
3)Subtract your filled mold weight from your empty mold weight.
This will give you your weight of water in your molds.
Alumilite clear has a specific gravity of 1.04,
4) So take your weight of your water, and divide it by 1.04.
5) Then divide this by 2, this is how much each A & B you will need.

 

[Curly]

Excuse me sir. Sir! Sir! Hand vigorously waving.

If Alumalite has a specific gravity of 1.04 and water is 1.0 then wouldn't that make the Alumalite heavier and you would need to multiply by 1.04, not divide?

 

[crabcreekind]

Excuse me sir. Sir! Sir! Hand vigorously waving.

If Alumalite has a specific gravity of 1.04 and water is 1.0 then wouldn't that make the Alumalite heavier and you would need to multiply by 1.04, not divide?

My mistake, proportions...

Mw/Ma = SGw/SGa

It was late, and just got done with a bunch of homework :coffee: