Search My Blog

Wednesday, October 6, 2010

Greensand casting Step-by-Step Sand Casting Instructions

Step-by-Step Sand Casting Instructions

Foundry Sand/Greensand

In commercial foundries the sand is used over and over thousands of
times. Between uses, the sand is rejuvenated by adding water and mulling
(mixing and smashing). If you do not let the sand dry out all the way,
you do not have to mull, just add water. Sand grit is determined just
like sandpaper. 150 is very fine and 50 grit is coarse. Fine sand will
give good detail, coarse sand will give a pebbly or rough texture. I
If you look at the sand through a microscope there are gaps and spaces
like a sponge. Any moisture that turns to gas during pouring can escape
out the pores (gaps).
Other materials like plaster do not have gaps for the gas to escape.
The sand used in greensand is silica, common/ordinary sand. You can use
beach sand, desert's all good as long as it is clean and
fine. The sand is held together with bentonite, a powdered clay.
Bentonite is also used for wine-making, well drilling, patching dry lake
beds, cosmetics, farm-feed additive and milkshake thickener. Bentonite
is also sold in health food stores for abdominal problems. You can
purchase bentonite locally at well-drillers or well-drilling suppliers.

Helpful Hints:
1.Start casting with aluminum (low-melting), then try brass or bronze.
Practice with easy metals.
2.Finish molding before you start your furnace.
DO NOT light the furnace then start molding.
3.Greensand is about 6% moisture. DO NOT let your sand dry out! Keep it
covered or in a sealed container when not in use.
4.DO NOT melt aluminum cans. Can metal is covered in vinyl to protect
the can from the contents. All other aluminum is good to melt.

Molding tools needed:
Riddle (Sieve/screen), large hole cutter (1/2" copper pipe), dowels
(1/4" and 1/8"), rammer/striker (wood 10"x1.5"x1"), runner bar pattern,
spoon, trowel and parting dust (in the black sock). Mold on a clean
surface. Keep your sand in a sealed container to retain moisture when
not in use.

Civil War Plaque

Go there



High Quality Castings said...

Thanks for providing nice information about green sand casting instruction

Don's Deals Blog said...

Thanks for the info. It got me to looking around more and I found some good info and Videos too. See my new Post called, Investment Castings Lost Wax Investment Castings Research and Videos at...
Investment Castings Lost Wax Investment Castings Research and Videos
Go there...