I've read many threads about bumper repair, but they all deal with rips and tears. I have 2 low spots or dents in my bumper, the pic will sort of give you an idea. Is there any way to get them out?

 

My T/A has the same issue, not as severe. It may be the age of the plastic, and natural shrinkage/movement. Try a heat gun, see if that will help. Not sure which side you would want to heat it from to get rid of the dimples.

 

I'm thinking it's knee prints of a previous owner working on it maybe. I don't want to add heat and damage it worse untill I know what I'm doing.

 

heat is the only option slowly heat it and push it out. it may ruin the paint on the mask probablyy would have to heat it from the inside to lessen the chance of ruining the paint

 

I think if heating it up works, it will eventually sag again, and possibly weaken the bumper. I was wondering if there was a product that I could fill with, or if fiberglass would stick to it to stiffin it up.

 

"EverCoat Poly-Flex # 411"

 

According to Evercoat, Polyflex 411 is: "A flexible polyester glazing putty designed for spot filling and skim coating over repair areas on flexible bumpers and plastic parts. Its flowable viscosity is ideal for filling minor imperfections such as sand scratches, nicks, dings and gouges"

The dimples in your picture look a lot deeper than a 'skim' coat. The front and rear fascias are designed to be flexible. I would be careful about using a filler of any depth on the urethane fascias.

 

The best solution is the heat gun...unless the cover is reaching the brittle stage. If so, replacement is next.

There are several fillers especially made for repairing urethanes, but using a filler for that situation will be a losing battle.

 

Heat gun, that's how it's done. You have to use some supports to keep it in place while it cools. You have to use as little heat as possible and don't stretch it too far. I've repaired several bumper covers that way. The paint will most likely bubble so you will need to repainted.

 

It will settle in again. The heat is a temporary fix.

 

My opinion on the 411 is the same, and it looks worse in real life that in the pics. If I heat it up, is there a way to keep it that way? like fiberglass the back side or something?

 

the number one rule with any kind of filler is to keep it thin as possible. if you just filled anything that deep it will crack with hitting even the smallest bump. Us the heat gun from the back side to get the bumper as close to the original shape and then us the filler suggested to get rid of any low spots. I work at a body shop trust my word pal.

 

It's not if you do it correctly. You heat it up, especially the edges of the deformation, use wood blocks or something to apply outward pressure ( making sure the blocks are padded so no sharp corners and gently heat. By gently I men not bubbling the plastic. I use my skin as a guide, not too hot to touch, but too warm to hold. Repeat. Repeat light heating instead of one big overheat.

The plastic was deformed from its original mold shape, no reason it can't be deformed back. In fact I have found it will often spring back to its original shape on its own with some heat at the stressed areas.

Filler is only needed if its been gouged or cracked.

 

Are the chances high that it will sag again?

 

[quote=petrolhead;5454057]Are the chances high that it will sag again?[/quote

It will take about as long to sag again as it did to sag the first time.

 

Yes, the heat gun will work fairly well, but what I'd do after you force it back into shape, is to apply a compress of ice-cold water to help it maintain its new shape. Just be aware that the heat gun approach does not always work or that the results may not be as good as desired.

Needless to say, you want to have the bumper skin off of the car in order to reach the area properly.

Applying heat will actually make the area very maleable (as well as very hot), but without the ice-cold water, it will otherwise, sag again to its former shape, and from the photo you posted, your bumper will be a tough one to repair.

Anyway, I have a few posts on my builder's log about repairs I did to my car's rear bumper. Go to http://bit.ly/130oTfD and scroll down to post #138. The heat/ice water approach worked fairly well and it only yielded an improvement. BTW, I used the same approach on the front bumper cover and ended buying a used one that was not in as bad a shape.

You may also want to check out the Early Firebird Zone forums, http://www.earlythirdgen.com/forums/ as someone there may have additional tips.

Good luck, and keep us posted.

 

This is correct info. We have to do this to my buddy's Miata this spring. I would never use filler for somthing that deep and large. The nose is very flexable and filler will just crack easy with the amount you would need to use.

 

Thanks for the help guys! I guess there is no perminent fix for it. I will try the heat and ice trick and see what happens. I think that they are foot, or knee marks from the previous owner. maybe if I keep my feet off of it, it will stay straight!

 

I've been reading about evercoat polyflex. They say it can be spread up to an 1/8" over a large area and take 77 degree bends. This might work for what I need, anyone ever tried it?

 

I got mine back to acceptable appearance with heat. But the casting is so thin at that point that I think without supporting it somehow from the back, it will sag again. Mine was not as bad as the OPs though.

 

Heat is your friend.....But not too much. You only need enough to get it to move. A good hair dryer on medium setting and constantly moving should do it.