How to Make a DIY Ingot Mold for Aluminum, Lead or Zinc Casting

Difficulty Level (Easy, Medium, Hard, Insane):
Easy

Process:
I've used a square corn bread muffin pan to cast my left over aluminum but because the material is so thin, the 640 degree (C) molten metal warped the muffin pan quite badly to the point where it was hard to get the ingots out so I decided I was going to make a more permanent solution.

My brother in law generously gave me 3 feet of 2.500" by 1.500" square tubing (1/8" thick) so I took my metal band saw, set the vise to about 3 degrees and cut 8 pieces at 4" long.

After deburring the edges, I used my angle grinder to cut off the top piece of the square tubing (the end where the tubing was welded together. Then I used a grinding wheel to grind off any protruding metal that could prevent the ingots from sliding out.

Then, I used the vise and a 2.500" diameter piece of brass to press it into the c-channel pieces to widen out the top.

After that, I took some 1.500" wide by 1/8" thick flat bar, cut 16 pieces at 2.500" wide and welded them to each side of the square tubing pieces.

Lastly, I used some 1" angle iron to weld all the 8 finished individual ingot molds together into one unit.

Videos:

 
Pictures:

Some zinc ingots made using a square corn bread muffin pan

Some aluminum ingots made using the same corn bread muffin pan

The muffin pan taking its toll because the metal is so thin

The bottom of the muffin pan quite heavily warped

Starting out with some 2.500" by 1.500" square tubing

Cutting 4" pieces with a 3 degree angle on the sides

Welding some flat bar on the sides

All 8 molds welded and laid out to connect together

Using some 1" angle iron to tie the individual molds together

Reinforcing the outside with some more 1" angle iron

The finished ingot mold

Trying it out with some lead

Thirty four-pound ingots later

The ingots turned out really nice

Another view of the lead stack

My stash

Cutting up two square bars for the handles

After I bent and welded the handles to the ingot mold

Tools:
Metal band saw
Measuring tape
Marker
Square
Angle protractor
Angle grinder
Eye and ear protection
Belt sander
MIG welder
DIY MIG welder cart
Aluminum foundry
Foundry burner

Materials:
32" of 2.500" by 1.500" square tubing
28" of 1" angle iron
20" of 3/8" by 3/8" square iron bars

Cost:
$0.00

Time:
4 hrs

Savings:
$50

Conclusion:
Ah, it's so nice to have some decent ingots! Yes, go ahead, roll your eyes at me, Melanie!