G110 DA burned my bumper =(

[RamAirV1]

Re: G110 DA burned my bumper =(

Do fiberglass bumpers react the same or differently than plastic bumpers? Specifically with regards to polishing.

Both do heat up more quickly than aluminum or steel body panels. The same of course would apply to fiberglass hoods.

RamAirV1

[Tim Lingor]

Re: G110 DA burned my bumper =(

Your best bet, IMHO, it to have it air brushed. One of the problems when buying a vehicle used or even a new vehicle for that matter is that you have no idea if that bumper was painted or not. Usually when using a rotary polisher one must be VERY careful as the composite bumper material does not dissipate heat very well, which could cause a person to burn through or wrinkle the paint.

Now with the G110, while it is possible, it is pretty rare. My guess is that it was a repaint which was especially thin on the edges. The shop may not have used the proper flex agent and as a result, the paint pulled off. The other possibility is that the paint was already damaged/cracked though not visible. As soon as the pad touched it, it chipped away. Your damage does not look like a burn through but rather the paint chipped/flaked off...as the edges are too crisp. A burned through spot would have smooth edges...

Tim

[seth1066]

Re: G110 DA burned my bumper =(

This blow up also seems to confirm a repair/repaint, but it's not quite in focus. Scratches or sanding marks? And the curved ridge doesn't seem to be perfect, as in a virgin bumper.




One would think that it takes a bit of work to cause this damage with a G110.

That said, I've repaired a few bumpers and the product to fill in various dents and dings (or worse) is a special filler that has flexibility. That filler may have a lower temperature threshold than the normal factory formed bumper. Also, some of the repairs are done with a heat gun which may also change the original characteristics.

A bumper also requires a flexible type of paint, for obvious reasons. From the factory this paint is noticably softer (as anyone who has used a rotary on a BMW bumper can attest to). Repaints though, typically tend to be even softer.

Here's my wild guess:

The bumper was damaged, repaired and then repainted with non-flexible paint and without any adhesion promoter (usually suggested in this application).

The pad may have lingered too long, which might have been ok perhaps on a factory virgin surface, but the repaired surface underneath this paint heats up and then the paint being non-flexible, breaks off causing the ragged edge. Perhaps some extra heat and/or damage occurs as it gets on the pressurized and moving pad.

BTW, technically these things are bumper covers for the the metal structural assembly that lies behind the cover and styrofoam.

[seth1066]

Re: G110 DA burned my bumper =(

The sentence beginning with "From the factory this paint is noticably softer..."

should read with the added wording (in italics) :

From the factory this paint is noticeably softer than the rest of the car...

[CieraSL]

Re: G110 DA burned my bumper =(

Both do heat up more quickly than aluminum or steel body panels. The same of course would apply to fiberglass hoods.

RamAirV1

Not to thread hijack here, but since we're on the topic of bumpers I might as well ask. I would like to get a DA within the next couple of months. However, both my front and rear bumper are fiberglass. The front bumper has been replaced and painted, though to look at it you can't tell. Can I polish the bumpers with something light, like Swirl X or DC1 on a polishing pad, or am I best to leave them alone. I'd rather leave them than risk ruining them.

[seth1066]

Re: G110 DA burned my bumper =(

Do fiberglass bumpers react the same or differently than plastic bumpers? Specifically with regards to polishing.

What kind of car/truck?

[Markus Kleis]

Re: G110 DA burned my bumper =(

That doesn't look like a normal "burn through" to me. Any chance you could get some more pictures, macro and standard?

Also, typically when you begin to burn through you will notice it first in a very small spot, and then as you keep working it will spread.

This spot looks quite large- how long were you working in the exact same spot without moving the G110 or checking your work?

I'm also a bit puzzled by the total lack of paint/pigment transfer to the pad.

Some more information would certainly help us to find the cause and solution.

[benedict]

Re: G110 DA burned my bumper =(

I will try and get a macro pic tomorrow. The spot is only about the size of your pinky nail.

The G110 was moved around and it did not stay in one place for long. As for the pad being clean, I took the picture of the pad after putting it in the washer.

[reasoned]

Re: G110 DA burned my bumper =(

It looks like the paint is chipped, not burned - and the pad got snagged on the chip which is why your pad almost ripped.

This is either a bad repaint or a touch up job that was on its way to failure. I do not think this is paint 'burning'. Not much you can do about it now other than repaint I think.

[benedict]

Re: G110 DA burned my bumper =(

here are a few more pics. also, how would i be able to tell if the bumper was repainted, without the obvious- asking the previous owner? ..haha

[seth1066]

Re: G110 DA burned my bumper =(

here are a few more pics. also, how would i be able to tell if the bumper was repainted, without the obvious- asking the previous owner? ..haha

Tough to tell from those pics. You could check it against the paint grain, surface, peel, etc. with the front bumper. Look underneath for overspray on anything that is not the bumper cover itself. Tape lines and sanding marks in the finish are also a giveaways.

[al_h]

Re: G110 DA burned my bumper =(

here are a few more pics. also, how would i be able to tell if the bumper was repainted, without the obvious- asking the previous owner? ..haha

I think I am seeling the plastic wrinkling in this picture. The DA can still get very hot even with the polishing pad when the lubrication of the product is completely evaporated.

Using a smaller pad may give you more precise polishing around corners.

[cnfowler]

Re: G110 DA burned my bumper =(

That clearly looks like a burn through. The plastic is wrinkled. Given the clockwise rotation of the DA, the paint probably began to wrinkle as it heated up, then the whole piece of paint was torn off hence the clean edge on the left side and the smeared/smooth edge on the right side.

Colin

[RaskyR1]

Re: G110 DA burned my bumper =(

Based on the texture in this pic, I would say it has been repainted. As the paint cures it shrinks down a little and can leave the panel with this tight textured orange peel like you see cicrled in red. You can also look for dust specs in the paint as another sign of a repaint.




Here is an extreme example of the texture on a panel that I know was repainted.



factory orange peel usually looks more like this...

[seth1066]

Re: G110 DA burned my bumper =(

Based on the texture in this pic, I would say it has been repainted. As the paint cures it shrinks down a little and can leave the panel with this tight textured orange peel like you see circled in red. You can also look for dust specs in the paint as another sign of a repaint.

I agree.