Thinking of dabbling into metal casting.

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Kaleb

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After a few talks with my reluctant Dad, I'm going to try and start doing some metal casting in zinc(the type used for diecast stuff), lead, aluminium and possibly brass or bronze. The plan is to melt the metal in a wood fire using a steel can as a crucible (the coals get a nice bright red glow in a good fire, so it's pretty hot in there). I intend to make greensand by mixing clumping cat litter with cement-making sand, using wooden patterns made using a router. Is there anything I need to know before I start?
 
I have heard the fumes can be toxic, expecially with lead.

Handling lead is not recommended either.
You may consider a lead-free alloy if it is not too expensive.

I would recommend a full face shield and some heavy gloves/clothes.
If you have moisture in the sand or molds, I have heard it can explode when molten metal hits it.

I would err on the side of caution, you can always buy more gloves and faceshields.

Pat J
 
Kaleb said:
After a few talks with my reluctant Dad, .............. Is there anything I need to know before I start?


Kaleb, your Father obviously has his reservations about you carrying out this undertaking into metal casting and probably for good reason. Check out some publications at the library and study the material until you can recite it from memory. DO NOT use clips from the internet and Youtube as subject matter, there is far too much stupidity on there from some real dumb-assed individuals that have gotten lucky in the past and have put there exploits up for the world to see but escaped injury only by shear fate alone. Not all of them are idiotic but there are so few good ones that for a rank amateur beginner, it is hard to tell the good from the bad. Use ALL of the proper safety equipment such as leather boots, safety glasses and full face shields as well as a full leather apron, full length trousers (no shorts) and cuffed gloves. This may seem over the top but if you have ever witnessed the resulting scars let on the ankles and toes of some schlep that was wearing tennis shoes while doing a pour and got splashed, you will understand. I have and still think the fellow to be a moron for having done so. The guy was extremely lucky to not have lost a foot in what did not have to happen. Pattern making is an art unto itself. The patterns require a percentage of oversizing and side tapering in order for them to be removed cleanly from the sand after ramming. You have a great deal to learn but above all, be smart, be careful, and be safe.

BC1
Jim
 
Read up on casting A lot.How to cast small metal and rubber parts ,William A Cannon. The metal casters Bible C.W. Ammen and the Complete book of sand casting Are a few that come to mind.

Lead and zinc will likely melt over an open fire a bullet casters lead pot will melt low temp stuff as well. Lead and its alloys are no that usable for model applications. pure lead is very soft wheel weights and Linotype harder. Can lead be handles safely at home by a teenager ? Yes,I have done it. When I was your age my dad and I melted probably over a hundred pounds of lead and cast sinkers and various projectiles. I was never seriously burned no property damaged and I grew up healthy.
Plenty of ventilation out doors under cover is best if indoors serous active ventilation like range hood. Wear gloves and face protection. Aluminum makes great molds for lead. You do need the mold up to temp or your "part gets all" wrinkly"

I would never use a metal can on an open fire for a crucible. Get a plumbers cast iron pot or a old cast iron cook pan at the very least. a steel can is just too thin and dangerous.

Aluminum can be melted in and enclosed furnace fired by charcoal or propane and forced air. Again at the minimum a plumbers pot for a crucible. Bronze higher temp . you will likely need propane and a real crucible not steel.

All molds and patterns need draft. ( Min 2 degree angle per side ) make you sprue larger cross section than your part that is where the bulk of shrinkage should happen.

Safety first and always Foundry work can be a fun hobby but a lapse in judgement can maim you, kill you, or burn down the family homestead.
Do your homework. Foundry work is an old trade but much to learn .
Regular clothes will not protect you from molten metal.
leather gloves leather jacket leather chaps and pull on boots . Face shield and safety glasses ie double eye protection.
Under the leather wear fire retardant clothing.

Do not pour aluminum or brass over a concrete floor spilled metal can make the concrete floor explode at the surface. And moisture in a piece of scrap placed in the melting pot can also go boom.
Tin
 
Don't use a can.

I made a crucible from a 4" diameter steel pipe 1/4" wall thickness with 1/4" steel plate welded over one end and a 1" water pipe 4 ft long as the handle. I built 2 of these one is 4" long the other is 6" long. It works great in my home made gas burner.

I have a 3 legs gas burner that runs on propane it takes about 30 minutes to melt the zine I need to pour a casting.

I have two 5 gallon buckets of sand.

I have not done any castings in 10 years. I am planning to move 1640 miles west to Phoenix area so about 75% of the stuff I own is for sale. I have about 300 lbs of zinc I can sell to the scrap yard for a good price but I was hoping to sell this to someone that can use it.
 
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