Wrench Tips #11 - Welding Plastic

Wrench Tips - Tip #11: Welding - It's Not Just For Metal

This tip comes courtesy of MotoIQ nerd and fellow LeMons racer John Walker. I haven't actually tried this yet, but I'm tempted to go break somthing just so I'll get a chance to.

It turns out that with the proper application of heat, zip ties and desperation, you can weld plastic. Observe Walker's welding of a broken radiator end tank on his LeMon.

Like any welding, the process starts with getting things clean. Soap and water is good enough. Next, a propane torch provides the heat, and your least favorite screwdriver transfers it to the plastic. Heat the screwdriver tip until it glows, jam a piece of zip tie (plastic welding rod) into the crack, and work it in with the glowing-hot screwdriver tip. There will be sizzling. There will be toxic fumes. You should probably wear gloves and avoid breathing. You should also be careful to work carefully around the entire seam, dilligently sealing every last bit of it, espeically if you're so bold as to be trying this on a radiator.

Welding plastic is an act of desperation. In a perfect world, when a critical part like your radiator cracks, you replace it rather than risk the consequences of a second failure. Reality is seldom perfect

Propane, a screwdriver, and zip tie welding rods in action.

We never said it would be pretty.

 -Dave Coleman

Got any tips of your own? email them to dave@motoiq.com!