filling with polystyrene or melted bumper

[pmarc]

I wonder how important it is to know exactly the type of plastic my car bumper has to be in order to fill cracks by melting a used bumper or placing polystyrene foam into acetone to produce the filler.

[Bob K]

It’s only important to know the name of the material the bumper cover is made of to choose a product that is compatible with it or otherwise find a patch material recommended by the product manufacturer to use for repair purposes. If you are going to make up your own patch material and test it then I see no reason to bother to identify the bumper material unless you want to inform others what works and what doesn’t on a particular kind of material.

Bob K

[Len]

I wonder how important it is to know exactly the type of plastic my car bumper has to be in order to fill cracks by melting a used bumper or placing polystyrene foam into acetone to produce the filler.

If you purchase a "Surface Modifier" and some repair adhesive you don't need to know anything except how to sand it smooth. I use Fusor #602 and Fusor #142 or 143 (depending on the amount you need) they work great and I've never had it fail when done properly. Check out our plastic repair page located HERE.

If all you need is a small tube you can avoid spending a lot of money on a dispenser gun and just get a "caulk gun conversion kit" for $6.50.

[pmarc]

It’s only important to know the name of the material the bumper cover is made of to choose a product that is compatible with it or otherwise find a patch material recommended by the product manufacturer to use for repair purposes. If you are going to make up your own patch material and test it then I see no reason to bother to identify the bumper material unless you want to inform others what works and what doesn’t on a particular kind of material.

Bob K

I think getting a used replacement bumper - same model as car - will guarantee it's the same material. This doubles my bumper cost since the salvage yard has other [crap] bumpers hanging around they can't sell as well. But a melted bumper gives me probably 1 - 2 quarts of filler. I'll need it all, considering amateur mistakes and it's a big job.

[James M]

I think getting a used replacement bumper - same model as car - will guarantee it's the same material. This doubles my bumper cost since the salvage yard has other [crap] bumpers hanging around they can't sell as well. But a melted bumper gives me probably 1 - 2 quarts of filler. I'll need it all, considering amateur mistakes and it's a big job.

What year, make and model of vehicle are you working on ?

[Henry]

I think getting a used replacement bumper - same model as car - will guarantee it's the same material. This doubles my bumper cost since the salvage yard has other [crap] bumpers hanging around they can't sell as well. But a melted bumper gives me probably 1 - 2 quarts of filler. I'll need it all, considering amateur mistakes and it's a big job.

I see no gain to what you want to do and you would still have to skim coat the proper filler over your repair. Your idea does have merit but too much against it.

How do you plan to 'melt' the donor plastic? You DO NOT want to be breathing that stuff. Not sure if this is something you want to experiment with or create your own filler.
If you use a flame to melt then you will have charcoal film over the parts which will hinder the adhesion.

Proper repair materials are more than available so why even bother unless as an experiment. You might be able to use a plastic welder kit to do what you want. Not sure if you thought of that. On a split bumper you would still need somthing to bridge the two pieces. Let us know what you do.

Henry