Trying casting for the first time, is my sand too wet?

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LittleForge

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Hi all,

I bought some greensand from Artisan Foundry but I can't seem to create a mould. I use talcum powder to help the two halves separate but it never comes apart cleanly like I've seen in demonstrations and any attempt to remove the part causes the sand to crumble.

When I do the squeeze test it it tends to hold it's shape but it doesn't snap cleanly. Is my sand too wet? Or dry? Or some unholy mixture of the two?
Any other advice you can give to a novice caster would be gratefully received as well.
 
From what little i know probably yes it is too wet. i believe it should be 3 - 5% max if green sand mix
 
Casting sand.
Take a small hand full in your hand a squeeze into a ball.

Your hand should be clean, the ball should then break under firm hand pressure with out and crumbs.
Plus be a clean break.

When filling the mould.
Dust the pattern with dry chalk. You want it fully covered.
sieve the sand over the pattern and pack well. fingers and hands first.

Then fill and pack well with rammers.

Repeat for both halfs.

Cut the fill, and spues to vent.

Then using welding rod poke vent holes, near but not onto the void left by the pattern.

4 vents per 1Sq" of pattern.

Oh, when removing the pattern, tap down, then using two lifting pins, pull straight up.

The metal needs to be at the right temp, I use wax blocks to measure mine.
Pour in one smooth pour.

Do not leave in the mould any longer than you need to.

Hope this helps.
 
This, below is what can be done with a home set up.

This hammer was cast at home.

DSCN0255.JPG

I worked my way through, making coke, charcoal.
Melting alloy, very easy.
Copper. Nice to do.

Brass, need to watch the temp, very close.

Ferrous.

A few mishaps, like melting to bottom of the furnace.
Ooops.

Learning how to control the air flow, a few dead blowers and such.

The steel for this was old fittings, spacers, nuts and bolts salvaged from a dead 205 gear box

DSCN0256.JPG

Issues in the casting?
A few.
The sand in the coup dried at a faster rate than the drag, leading to a sag.

Metal was just over casting temp. The pouring poet was cooling to fast. But we got the metal in before it closed up to much.

Not enough vent pricks.
 
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