Moulding sand

[Frank Erskine]

Does anyone know of a source of small quantities of moulding ("green") sand and parting sand? Preferably in the NE.

TIA -

[Andrew Mawson]

("green")

John Winter & Co (01422-330493)

AWEM

[Frank Erskine]

Many thanks Andrew.

[Holly, in France]

Have to ask, what sand is this?! Moulding as in making moulds or moulding as green and mouldy? :-) Parting sand?? Do tell......

-- Holly, in France Holiday Home in Dordogne

[Chris Bacon]

That's it.

[Andrew Mawson]

("green")

Moulding sand - used in foundries for producing the female form into which molten metal is cast in the 'green sand' process. Typically the sand is actually a redish black colour in fact. Sand from the Mansfield area was used historically - the sand needs to have suitable sized particles (to give permeability and the required finish) and some form of binder to keep it in shape. Sand is now screened to size and blended with bentonite (a clay) to give the required properties. However the green sand process has largely given way to the resin bonded process (resin pre-mixed with sand in a hopper, and mixed with a catylist as it is drawn off for use) or the Silicate process (dry silica sand mixed with sodium silicate - {waterglass or issinglass} and hardened by blowing carbon dioxide through the mould.

Parting sand is silica flour, and is put between the two halves of a mould (cope and drag) and on the pattern to prevent them sticking and allowing the pattern to be removed to form the cavity without sand clinging and marring the finished item.

AWEM

[owdman]

I used to use slightly damp builders soft sand to make moulds for lead sash weights. It usually has enough clay in it to keep its shape. Come to think local (Matlock) builders merchant sand is often reddish and probably comes from Mansfield area. Are industrial sand moulds re-used or just once only?

cheers

Jacob

[meow2222]

I've seen the old sand process in action in industry: the sand form comes apart as the item is released from the mould. The sand is reused is another mould.

Perhaps the more modern versions allow the sand form to be reused to some extent?

NT

[Holly, in France]

details....

Many thanks for such a detailed explanation Andrew. I have vague memories of seeing sand moulds during a school trip to a bell foundry in Loughborough (?) in the early 70s. I really should have paid more attention at the time :-)

-- Holly, in France Holiday Home in Dordogne

[manatbandq]

We used it *in* school in the 70s, for casting. That was when we had proper lessons.

MBQ