Reshaping urethane bumpers
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Reshaping urethane bumpers
I searched, but couldn't find anything that really told me what I was looking for...
Where the front license was mounted/screwed into the front bumper over, I've moved the plate but now have 4 holes to fill. But that's the easy part.
Al 4 are also "raised". Feels almost like all spots are being pushed out from the back side. Not simply 4 holes in a flat surface.
Can they be heated & "pushed" back down, the urethane "puttied" back flat? Or do they need to be sanded down thinner, to be flat again? Or even, God forbid, just cut out and replaced sections?
Where the front license was mounted/screwed into the front bumper over, I've moved the plate but now have 4 holes to fill. But that's the easy part.
Al 4 are also "raised". Feels almost like all spots are being pushed out from the back side. Not simply 4 holes in a flat surface.
Can they be heated & "pushed" back down, the urethane "puttied" back flat? Or do they need to be sanded down thinner, to be flat again? Or even, God forbid, just cut out and replaced sections?
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Re: Reshaping urethane bumpers
you could remove the raised part and fill in the hole with fiber glass resin. or if you are good with a soldering gun you could "weld" the holes up with plastic but it has to be the same stuff your bumper is made of or it wont work it all depends on how big the holes are.
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Re: Reshaping urethane bumpers
you could remove the raised part and fill in the hole with fiber glass resin. or if you are good with a soldering gun you could "weld" the holes up with plastic but it has to be the same stuff your bumper is made of or it wont work it all depends on how big the holes are.
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Re: Reshaping urethane bumpers
I have some urethane mix to fill the holes with, that's not my problem.
The problem is the RAISED sections around the holes. Its kinda like something PUSHED the areas around the holes, into zit bumps!
I need to lower the raised sections. I could just sand them down, but then those areas would be thin & I dunno if being thin, would cause the the flex & distort in heat & cold.
What do I do about the RAISED portions, to lower them?
The problem is the RAISED sections around the holes. Its kinda like something PUSHED the areas around the holes, into zit bumps!
I need to lower the raised sections. I could just sand them down, but then those areas would be thin & I dunno if being thin, would cause the the flex & distort in heat & cold.
What do I do about the RAISED portions, to lower them?
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Re: Reshaping urethane bumpers
Mine was the same way before I painted it the first time. I just filled all 8 of the holes with bondo and sanded the humps around the holes down smooth. You've looked at it several times....can you see any evidence that a plate was ever mounted?
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Re: Reshaping urethane bumpers
Yours looks good. My only concern is how thin it might be after sanding the bumps down.
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Re: Reshaping urethane bumpers
The urethane will soften and reform to some degree if you use a heat gun on it and push it into shape. be careful because it can get very hot.
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Re: Reshaping urethane bumpers
C'mon Stephen...
The only reason that you would have to take your fascia off is to put your extra one on after you've already filled the holes, reinforced them, sanded them down flat, and repainted it.
You do still have that extra one in your shed don't you?
The only reason that you would have to take your fascia off is to put your extra one on after you've already filled the holes, reinforced them, sanded them down flat, and repainted it.
You do still have that extra one in your shed don't you?
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Re: Reshaping urethane bumpers
Yep....I do still have the extra parts from the 89.
I suppose I could clean that one up, then just swap them out......Hmmmmm.....
I suppose I could clean that one up, then just swap them out......Hmmmmm.....
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Re: Reshaping urethane bumpers
.....At this exact moment in time Stephen has already pulled the spare fascia out of his shed and is already working on it.
#16
Re: Reshaping urethane bumpers
I've tried to reshape the top of my 86 firebird bumper because it sunk in areas or something and it worked decently with a heat gun.
If the area you are trying to work on is flat, maybe try an iron (the one you use to iron clothes). Have something flat on the backside. A small iron like something from fisher-price(a toy) would be ideal but I don't know if they make such a thing. You're going to want on even distribution of heat to smooth them out and I'm thinking a heat gun won't do that. Just an idea, I've never tried using an iron.
If the area you are trying to work on is flat, maybe try an iron (the one you use to iron clothes). Have something flat on the backside. A small iron like something from fisher-price(a toy) would be ideal but I don't know if they make such a thing. You're going to want on even distribution of heat to smooth them out and I'm thinking a heat gun won't do that. Just an idea, I've never tried using an iron.
Last edited by Firebat; 12-09-2008 at 10:38 PM.
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Re: Reshaping urethane bumpers
I'd definitely try a heat gun on it, the plastic expands when you drive a screw into it and should come back into shape. Warm them up good and press them flat ... or even in slightly. I use a body hammer as an iron after the plastic is hot. If that fails make a bigger hole, since you're going to do a plastic repair on it anyway. And please don't use fiberglass and resin. Weld it up or use a plastic repair material ... either urethane or epoxy. We use this companys products for welding plastics at the shop. http://www.urethanesupply.com/ and they have a lot of good "how to" info on their site.
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Re: Reshaping urethane bumpers
Here is one of the bumps I'm talking about, that need to be flattened down, from the license plate mount screws.
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Re: Reshaping urethane bumpers
Now I see! It's not just the hole it's the whole area. The heat gun is your best bet. If you're familiar with shrinking metal with an acetylene torch and water you can do the same with a heat gun and an icecube. But it should be much better with just heating it and ironing it out.
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Re: Reshaping urethane bumpers
It's not the whole area. Just 4 bumps where the front license plate mount was screwed in to.
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Re: Reshaping urethane bumpers
If you really want to reshape it, you could try. My experience is, to not bother with it, and just replace the bumper. Its one of those things, that if it bends once, it will stay that way. You may be able to unwarp it temporarily, but i bet it will come back.
Either swap out the nose completely, or id recommend scuffing the urethane around the bumps, building up some urethane on top to be flat with the highest points on the bump, and then sand the larger area smooth.
If you just filled the holes, i bet the "raised" area will keep coming through every few months after a few heating and cooling cycles.
Either swap out the nose completely, or id recommend scuffing the urethane around the bumps, building up some urethane on top to be flat with the highest points on the bump, and then sand the larger area smooth.
If you just filled the holes, i bet the "raised" area will keep coming through every few months after a few heating and cooling cycles.
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Re: Reshaping urethane bumpers
I had a feeling that it was larger than it initially sounded. That is very common deformation from the license plate bracket. I'd have to agree that if you want it truely straight again, you need to replace it. You will be able to improve the condition with a heat gun though if you aren't looking for a perfect bumper to repaint.
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Re: Reshaping urethane bumpers
i had the same problem, i had my plate removed and used a bracket that mounts under the front of the car. The body shop used the heat gun method to flatten out the bumps, im sure there is some re-finishing involved after that, sanding and some plastic filler im sure. But it worked, my bumper is smooth and there is no sign of the bumps. But like said before, dont get the material too hot, it will burn.
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