Author Options:

Green sand options? Answered

I finally finnished my testing prototype of my metal melting furnace.
Did a few casts to get short rods for the lathe work and noticed a big problem.
I used washed play sand as itwas the finest sand I could find locally.
The result was good in shape but very bad in terms of surface quality.
For another test I used the leftovers of my crushed perlite and mixed it bentonite and the surface was really smooth - but using perlite is not really an option.

Real green sand is hard to get in my area and the postage costs for a 20kg bag are just too high on top of it.
So, before I start hunting down all sand and soils shops nearby: Is there a proper name for extreme fine sand or a good alternative for a reusable casting media?



Best Answer 3 years ago

Hi Downunder Ive done a little bit of casting but haven't done it for a while, I found a local foundry and bought some sand, resin and catalyst, and mixed up in with a cake mixer. They said that green sand it pretty much obsolete, and they hadn't used it for years. Ive used both systems and one you tried the resin system you would never go back to green sand. You get fantastic detail and it just much better to work with. As i understated it you can use any clean, fine, dry sand and just add the resin and catalyst. Now where you get the resin from in your area i another question.

here is some info,


Where abouts in OZ are you?


Answer 3 years ago

That looks indeed great but I don't think for the little bit that I do it would be justified to invest in a binder like this.
If I really need fine details I revert back to a sand and plaster mix but cleanup is a pain.
Found some much finer sand today and might do another test next weekend.
Although I am in the Melbourne area, which is not totally "bush" getting certain things is a challenge in AU.
Where you might pay 20 bucks at a local store the price for the same item can be as high as 40 bucks down here.
On top of that comes the problem that most companies refuse to sell to the public unless you want to buy in bulk.
Could get "ready to use" and extreme fine green sand here but only in batches of 50kg or more.
Can't justify for the 5 to 10 castings I do in a year :(


Answer 3 years ago

I was just thinking , the resin Looks and smells very much like fiber glass resin. It might be worth a little experimentation. Mix the sand with the resin thoroughly before adding the catalyst


3 years ago

Have you thought of asking existing foundries if you could have "spare" materials for an art project?

Google says there are several foundries specialising in fine or art castings in and around Melbourne. Depending on their size, attitude and your persuasive skills, you might even get to do the casting on their premises...


Answer 3 years ago

Have to check them out one day it seems.
But doing any work there will be impossible thanks to our health and safety regulations.
As said I only do a few castings a year and usually collect a few projects until I fire the oven to make it worth the work and time.
Had a local guy doing wood fire oven parts and for most things his sand was good enough but now with some detailed aluminium work I would really avoid the cleaning and polishing as much as possible.
If all fails I will use the plaster mix again and just clean the fine details with a knife or thick needle, at least this way I have a nice and smooth surface finnish already.