welding plastic bags - mylar plastic sheets
Plastic bags can be welded together with soldering iron.
The resulting seams are sturdy and waterproof.
This is a very useful technique for making kites.
You need some oven paper and soldering iron.
I use a soldering iron with a flat tip and temperature control.
Place the first piece of plastic on the oven paper and mark where you want to make the seams.
Then put the other one on the first one aligned with the mark.
The plastic pieces are slippery and they like to run away.
You can make them stick in place by slightly moistening them.
Now put another piece of baking paper on top of the plastic.
You should be able to see the mark through paper.
That's why it's a good idea to use light colors and avoid black plastic.
The pressure on the soldering iron is very small, and it will move along the seam to melt the plastic sheet.
It is important to keep the tip so that the entire surface of the tip is in contact with the paper.
The correct speed depends on the thickness of the plastic.
Because HD is thinner, low density plastic is easier to weld than high density.
When you finish the seam, check it and test it by taking it apart.
After some practice, you will know the correct speed and pressure of different materials.
Make a kite or inflatable item or something with your new skills!