Using Paper Models and Casting Foam For Lost Foam Casting

 

It almost seems absurd using paper models for metal casting and I will add that this technique is entirely experimental at the moment. Pictures will be posted soon.

 

OK So what we’re going to make is a rammer. The plan for the folded paper model is here. The plan is based on dimensions provided by Tim Williams.

 

Materials:

Cardstock

Hobby knife

Straight edge

Glue (White school glue works fine)

Paraffin or Bees wax or a bunch of candles.

Casting foam (Available here or here)
  * Forget the spray foam, it's given me nothing but problems.

 

1. Download the pattern and print it out on cardstock, its 4 pages.

 

2. Cut out the handle, roll it around a pencil to set the curve, and glue the tab on the outside. All tabs will be glued outside except for noted exceptions. This keeps the tabs from being translated into the foam. HINT: An hobby knife and a straight edge helps here.

 

2a. If you’re going to be using pour foam, glue the Handle Cap onto one end of the handle form. If you put the cap on for spray foam, air will get trapped at that end of the handle and the foam won’t be able to displace it.

 

3. When the glue has dried, give the handle form a good wax dip. This keeps the foam from bonding to the paper.

 

4. When the wax has cooled, spray or pour your foam into the handle

 

5. Wait for the foam to harden according to the manufacturer’s directions. The spray stuff from Home Depot, which is what I’m using, takes about 8 hours to cure completely. The other stuff is advertised as curing much faster.

 

6. Once the foam has cured, cut the ends that have oozed out with a sharp knife or a saw and peel off the paper. You now have a 1 inch foam dowel 8 inches long.

 

More to come…..