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Problems with the sand mix?

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shipto:
I have added a few pics of the results of my attempts to create a green sand mold but despite putting plenty of powder the sand is sticking together.
I first thought it was too wet so added a bit more sand to the mix and tried again, the results of which you see in the pictures.
I am now thinking that maybe there isnt enough clay in the mix but would like to see if anyone thinks its possible. I origionally used approximatly a 10 to 1 mix but that was before adding the extra sand.
The drag? actually turned out pretty well concidering I forgot the powder on the pattern it pulled away a little (circled) and the core? pulled away too but i think I need to increase the angle on the pattern for that to work.

awemawson:
Do a 'squeeze test' on the mix. Take a handful and clench your fist with it in it. Relax your fingers to a flat hand. The sand should take the impression of your fingers, but the bit you've squeezed should be able to be picked up. Holding both ends with thumbs and two fingers, bend the sample. It should break cleanly showing exposed edges like cracked cast iron.

Too much clay and moisture and it won't leave your hand cleanly.

Too little clay and it'll crumble and not break.

Moisture content should be about 4%   by weight

shipto:
I did try to take a pic of the squeeze test too but trying hold sand in one hand phone in the other and press the button with my nose didnt work out too well  :lol:
However mine was much more crumbly than that so more clay may be in order will try it tomorrow.

NeoTech:
And to much clay it will stick to everything and just not let go. =)

shipto:
Added more clay tonight and got much better result on the drag but I need to mix it more I think the cope pulled a big lump away but it was very rich with clay where it happened. This is the problem with having to work for a living you rush stuff.
Anyway car has to go in for new brake cylinder on friday so I am going to take the day off and can spend the full day in the shop getting it right which usually means it goes right in a short amount of time, if so I might even try for a part. Fingers crossed.

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