I found this forum posting about making a homemade Sandbag. These are important tools if doing sheet metal forming, especially in steel. Here is the original posting.

If you've ever done any metal forming odds are you've used a sandbag. These are about as fundamental as you can get. The problem is though, if you’re not a professional your rarely going to use it enough to justify the cost. Eastwood sells a nice one for around $50, I own one... I have no idea where the hell it’s at, and I’ve only used it a few times. So it came time to do some metal shaping, and after not being able to find it (guess someone borrowed it or it walked off… happens) I decided I was going to make one. So I get to thinking- what’s cheep, easy to find and is pretty strong, only thing I could think of is leather- which is what most are made of. So later on I went to get something out of my closet and see an old pair of jeans hanging there, knowing I wouldn’t wear them anymore they should have been thrown away years ago. So that sparked my imagination (as scary as that is sometimes...) and here is what happened.

1. Take your pair of old jeans (or buy a pair if you don’t have any laying around, can probably pick up a pair at the salvation army or thrift store for a couple bucks, big some that are big) and cut about a foot and half off the bottom of the legs leaving you with a demin tube.

2. Head to your local hardware store and pick up a tube of silicon chalking ($1.50) and a bag of sand ($3.50).

3. With silicon in hand run a large bead of it about 1.5" inside of the leg on the bottom all the way across and lightly press the sides together, now you have a pouch.

4. Do the same with the other end only leave about a 1" opening at one end.

5. Let silicon dry for a few hours. Sit down and drink a bottle of water or coke, you've did a lot of work already.

6. Take that bottle you just finished off and cut it in half, leaving you with a funnel and a cup pretty much.

7. Take your sand, pour it into a bowl. Take the top part of the bottle (the funnel) and stick it in the hole that you did not silicone, take the other half and start filling the bag up with sand. You don’t want it rock hard, but full enough to completely fill out the bag.

8. Fill that hole where you filled it at with silicone and run another large bead down both ends of the bag. Let it dry.

9. I took the other leg of mine and slid it over the bag and then silicone it also to make it a little thicker, this is not required though.

10. You now have a sand bag, go beat some metal to your hearts content.

I've used mine for several hours so far without a leak or tear. This wont hold up to constent use, but if it springs a leak just add a little silicone. You could also sew the legs shut... but I dont sew. The feel of it feels just like any other sandbag I have ever used, the denim has a nice soft feel to it also.