You can use epoxy and JB WELD in places, but how do you keep them from flowing down or drooping?

The answer is polystyrene...

 

good old polly, even used as the filler between layers of fiberglass in boats to make them stronger and increase flotation
then look at what is used to form cast in place house foundations? sheets of polly

 

Polystyrene (I meant to do a video on it, and may do that still if the rain lets up) is what saran wrap and soda bottles are made out of.

The story behind that is that I used to build wooden (BALSA) model airplanes, and always wanted to build a Guillows kit with a clear skin, so that it showed off the inner framing. I thought naturally about using plastic wrap for the skin - but I found out the hard way that NOTHING makes that stuff stick to anything else permanently.

Polystyrene calls for a special adhesive that you are not going to find anywhere, and so the bottom line is that no matter what kind of glue you use, even EPOXY, it will not stick to it...

*This is plot material

So what that means is that if you use plastic wrap or cut up soda bottles to hold any kind of glue in place - you can peel the polystyrene off after the glue or whatever sets, leaving a nice smooth surface behind!

NOW: We all know the only reason J B Weld is a pain to apply and shape is because it runs, drips, droops, etc...

If a layer of plastic wrap is used to hold it in place and in shape - it will dry and cure to the shape it is held to, and after that the plastic wrap can be peeled off like peeling a sticker backing!

I also noticed that you can massage and shape the goop through the plastic wrap without getting any nasty sticky goop on your fingers. You can form it with straight edges, and drive air bubbles out. You can use masking (or other) tape to hold the forming material (plastic wrap or salvaged bottles) in place so that it stays where you put it as it sets and cures. Different kinds of paper tape in fact help to maintain straight lines and edges


NOW - The obvious advantage of BONDO is that it tends to stay where you put it.
The advantage of Epoxy or J B Weld is that it is not porous, and forms a more solid bond.


And if you lay it on so that it bulges out, you can bring it back down to straight with a belt sander or file.

But who in hell wants to do a lot of sanding when you can get it close to right to begin with?


The bottom line here is that there are uses to plain old plastic wrap that can make our lives a lot easier when we are trying to match body lines, and also we can use materials that we normally would never even consider

 

Sorry guys. While I am sure both applications work as described. Neither are supported with polystyrene. Saran Wrap, by any name is typically a PVC derivative or even LDPE (low density Polyethylene). "Soda'' bottles are typically blown from PET (Polyethylene terephthalate). Two related but, much different products. Where's Bill Nye the Science Guy when you need him?

 

I was using a LOT of it on a dent that had to be shaped back out because there was no way to punch it out from inside. Under that circumstance it would have made a big sloppy run or drip, but the plastic held it almost perfectly. It ended up being a flat clean well formed match that I may just finish with glazing putty.

Best of all, since JB is non-porous the rain these last few days isn't messing it up.

 

You'll use a LOT less body filler if you use a stud gun Dutch. I have one and it's made body work a ton easier!

 

It's on my list - we have a Harbor Freight at the 6 O'clock point of the interstate loop around Memphis, roughly.

I have to have it to get the sills and over window areas pulled out of several of my toys, where either straps or slipped jacks punched in some largish dents.

If it can save the hood on the MX3, I won't have to hunt all over the place to find one of those either.