Possibly epoxy/ mat on customized teo plastic bumper

Doing another front end conversion custom reshaping & fitting this time a 2016 Camaro nose to an 83 el camino, replacing my 2010 conversion I did in 2009'. Did the first conversion reshaping with heat & hot air. plastic welding. Repairing this stuff is one thing, fabricating with it is a whole different tedious job. I've seen poly resin & duraglass stuck onto teo & other plastic bumpers before, but no way in HELL I'd trust that.

Better products open up new possibilities.

Haven't had spi epoxy long enough to test it much. Wondering if I applied it over sound sanded factory paint or over adhesion promoter on non painted parts, could this give enough adhesion to use epoxy resin & mat to extend & reshape an area? This would be a ton easier than reshaping & welding plastic parts together, especially on making a new flange.

You never want to use resin or chopped fiberglass over epoxy, as they all made different and some work and some peel right off.

Thanks Barry. Not the answer I was hoping for, but it was a thought.
So is it a possibility that some manufacturers epoxy resins could chemically bond strong enough to epoxy primer in the 7 day window, or just not worth checking into further?
Another possible thought I had IF some brand of resin could have decent enough adhesion would be to bend the plastic back inwards a little extra &drill small holes at the ends to allow a mechanical bond from inside to outside.
If there is some chance of some types working, doing a few stress test experiments could be worth it.
If not, back to making 2 sided forms to reshape & hold plastic in to hot air weld.

As with many of my projects, if it was easy ,other people would be doing it.

I know 3m 8115 and SEM 39767 will stick to SPI epoxy, it might be possible to bond cured panels to metal with the 8115 and use 39767 to help shape the TEO.

Thanks crash, I was kinda wondering if 8115 or something could be used to bond a cured fiberglass part to the epoxy primed teo part since Barry said resin on the epoxy may just fail. Guess i'll do a sample test of it. As far as bonding teo to itself, hot air welding with my steinel lcd gun & ribbons or donor material strips has held out excellently. Haven't tried the sem stuff yet, but a red lord fusor I tried shadowed badly on a critical joint.
​I have to split the 2016 bumper in the center to narrow it &reattach, as I did on my 2010 conversion. This part was easy enough with welding.

Making the side profile of the 2010 bumper blend into an 83 el camino was no small task. Having to extend the sides with donor material, reshape, & make a flange was pretty difficult. Kept the forward profile of the 83 fenders, but shimmed out the center & reflanged the lower section to make less round like the newer cars. The 2016 looks to be even harder to blend in, so being able to just make the side from fiberglass & bond together would be much easier.

Well, after a little more research it seems there's still not much you can do even these days to get the kind of bond I want to a thermoplastics type bumper. So I might just do a minimal amount of plastic reshaping & welding & modify my steel fender flanges to match part of the new part AS IS. At least bonding metal with a tig is a sure thing.


​Crash, have you seen any long term results with the sem 39767 on plastic parts in areas with a little stress on them .?? Having bumped my modified 2010 front fascia lightly a few times & scraping a guard rail, the hot air plastic welding held out pretty good, but this red colored lord fusor product I used in a few spots failed miserably.

The test is not long term as to what crash said, the test is it will peel off in 24 hours or not at all..
I have used the duramix over epoxy both the semi ridged repair and the controlled flow and the self leveling seem sealer and it works fine, never fooled much with the sem to know.
If Crash says it works that is all I need.
Let epoxy set over night and then apply within 24 hours.

What is the difference between fillers with resin or chopped fiber glass (short or long stranded fillers) and resins or chopped fiber glass that will not stick to epoxy?

Never over the years had a problem until a shop called me where fiberal was peeling off and he had used it over epoxy for years, like I have.
I had two older bags of fiberal at home, tested and it was perfect, bought a newer batch and peeled easier then a band-aid.
So bottom line is these companies are not going to call you or me and say we changed the formula, so don't chance it.

Products suddenly changing can bite you. Manufacturers tend to without notice cheapen the formula, which may get by some test of theirs, but not your real world use.



Couldn't find any new info that I wanted to hear towards bonding to thermoplastics, so I'll stick to plastic welding that will hold up. Worst problem for me on projects like this is that pretty much all info on plastic bumpers pertains to repair, which is far less demanding the actual fabrication with it.

On some areas that I may need to modify plastic, the hot air welding may not be completely possible such as new inside corners, so I would like to know from experience if some have found certain plastic repair products to be better than others in a stressful application, such as attaching tabs.



Well, almost done with initial figuring to start cutting. Used lazer lines at night among other things to help figure things out.
​If I had any damn sense at all, I'd pick easier projects.



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Well, got the front nose conversion project to the bodyfiller before paint stages before getting my left forearm cut open from a section of falling window glass at work yesterday . Did hot air plastic welding on everyting needed.

​Tried the sem on a sample & stuck fine till stressed. Went to use it for real & it was hardening before I could fully spread a small area & later pealed off. Even a 2nd mixer tube clogged in a minute & was burning hot. Maybe the 94 degree evening temperature? So I sprayed spi epoxy & applied some poly flex to start, following with some z-grip I had since my built up areas won't flex much anyways &; polyflex doesn't sand that great.



Started an experiment sample. Sprayed 1 coat epoxy on a sample strip of rough sanded teo plastic with adpro. Then sprayed a heavy coat & stuck fiberglass mat to the wet spi epoxy. . Seems to be bonded ok, will try some resins & more mat on top of it when I can work again. Sometimes there's only one way to find out something new;;;;; on a sample Figured if some resins could work, it's worth a little experiment time.



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Update on my little experiment of sticking raw fiberglass mat into wet spi epoxy primer on t.e.o. plastic strip . In my stress test I gradually pulled harder & harder on the on the mat I had hanging off the test strip. Finally the epoxy pulled off the plastic, the fibers didn't let loose from the epoxy.
So I'll try it again later. I think I random rotary sanded the test strip with 120 grit, probably a used pad, wiped with the 700 water based w&g remover, let dry, & used SEM aerosol adpro spray , 2 coats before epoxy. Obviously something here in my process could have been better. If I get this better, this method could work for another project.