Anyone know what type of material OEM bumper covers are? (plastic welding question)

[Stranger in the Black Sedan]

I need to repair an extremely small crack in the edge of my OEM rear bumper cover, from some asshat hitting it in a parking lot. I am going to get a hot air plastic welder instead of using a 2 part epoxy.

I need to know what type of urethane the OEM bumper covers are so I know what type of plastic welding rods to use. Is it TPO, TPE, TPU, PUR, etc.


http://www.urethanesupply.com/identify.php

Thanks

Steve

[Green96]

Sorry, this made me laugh. I always tell one of the welders at work that welding is just gluing metal. I like to aggravate him because he takes welding very seriously.

Unfortunately I do not know the answer to you question. I would say that you need to be careful when selecting a grade for the repair. Regardless of compatibility you need to select a grade with a similar flexibility.

[Stranger in the Black Sedan]

Yeah they sell many many types of sticks. Knowing the parent material will drive me to select the same stick and then the weld will be as if there was never a crack in the first place. If you saw the size of the crack I am repairing you would laugh. It's about 1/4" long. Any body shop would fill it with flexible filler and move on but this cover was a brand new OEM replacement and I want to make it as-new again before I repaint it. Most bumpers will have a code on the back that tells you exactly what material it is, I have not looked on mine yet and sometimes it's obstructed when mounted on the vehicle. Just thought someone might know from experience or have a parts cover they could look at.

Steve

[Phrog_gunner]

Try giving Spectragod a shout, I know he has an extra bumper. I have one, but I'm two states away from it or I'd check for you.

[Mills Marauder]

i would repair it with a good epoxy that is made for rubber bumpers. kent automotive has alot of oem/icar certified epoxies that cover all the flexibilities of rubber plastic parts. the epoies can be sanded and smoothed to make it look as if never repaired. kent has a rigid, semi rigid and flexible epoxy and it explains which to use on each application.

[justbob]

Steve, i have had a good amount of schooling in plastic welding and i'm glad to see your doing this the right way. You will still need to grind down your weld a tad and fill lightly. With that said, most all plastics are clearly marked with a stamp on the backside. I know our grille is PPE for example by the stamping.

[Stranger in the Black Sedan]

I am aware of flexible epoxies. I don't want to use an epoxy because the bond will not be the same as performing a weld, from the reading I have done online. Although the crack i have is TINY, because these bumper covers have risen unbelievably in price, I need to make sure this repair lasts forever (or until some other asshat crashes into it). I figure I will notch the crack, weld it from both sides, and then after grinding the weld, use an epoxy to do any final filling

[ImpalaSlayer]

I am aware of flexible epoxies. I don't want to use an epoxy because the bond will not be the same as performing a weld, from the reading I have done online. Although the crack i have is TINY, because these bumper covers have risen unbelievably in price, I need to make sure this repair lasts forever (or until some other asshat crashes into it). I figure I will notch the crack, weld it from both sides, and then after grinding the weld, use an epoxy to do any final filling
please post some pics, i may wana bring mine to you

[Stranger in the Black Sedan]

LOL I have never done plastic welding before, I don't know that you want me fixing any of your stuff, no guarantee of what the result will be. I'll post a pic in a minute, you will laugh at how small the crack is but I am PISSED because I had to fight with a body shop and the insurance company to re-buy me a new cover after their multiple botched repair attempts on my original with epoxy, and once I finally got a half decent repair completed someone runs into it in a parking lot.

[ImpalaSlayer]

LOL I have never done plastic welding before, I don't know that you want me fixing any of your stuff, no guarantee of what the result will be. I'll post a pic in a minute, you will laugh at how small the crack is but I am PISSED because I had to fight with a body shop and the insurance company to re-buy me a new cover after their multiple botched repair attempts on my original with epoxy, and once I finally got a half decent repair completed someone runs into it in a parking lot.

some one hit mine in a parking lot too, i think its just the paint thats cracked though.

[Stranger in the Black Sedan]

it should be pretty easy to tell if the body is cracked, push on it. Mine is a small crack right on the top edge but it is very clear when you push on it, it spreads. I have the tools to do the paint work myself but I don't have a particularly clean area to spray at this house yet. Probably gonna give it a go though and make a temp booth, I have had quite a bit of collision work done by shops over the years and I have never once been satisfied with the result. Then I waste tons of time being the bad guy and bringing stuff back over and over again, it's just not worth it.

[Spectragod]

Duramix 4030, it will never break again in the same spot.

[ImpalaSlayer]

it should be pretty easy to tell if the body is cracked, push on it. Mine is a small crack right on the top edge but it is very clear when you push on it, it spreads. I have the tools to do the paint work myself but I don't have a particularly clean area to spray at this house yet. Probably gonna give it a go though and make a temp booth, I have had quite a bit of collision work done by shops over the years and I have never once been satisfied with the result. Then I waste tons of time being the bad guy and bringing stuff back over and over again, it's just not worth it.


yeah im pretty sure it just the paint but i dont wana go and make it worse lol. tell me about the clean place thing. i just painted a hood deck lid and bumper for a buddys stang and the dust was horrible. luckily hes a master with a buffer

[Stranger in the Black Sedan]

http://bondospecial.smugmug.com/Cars/2003-Mercury-Marauder/CT-memorial-day-weekend-035/886876299_aAcdK-XL.jpg

[Stranger in the Black Sedan]

http://bondospecial.smugmug.com/Cars/2003-Mercury-Marauder/CT-memorial-day-weekend-035/886876299_aAcdK-XL.jpg

[Mills Marauder]

in my shop we dont plastic weld anything. if my guys cant get the repair it right with epoxy we replace the cover, moulding ect. ive been trained in plastic repair with epoxy and plastic welding and i will tell you that an epoxy repair done right versus correct plastic weld the epoxy wins hands down. just my experience and 2 cents.

[Stranger in the Black Sedan]

mills, if you look at my pic of the crack, would you use the same duramix the other guy suggested, and would you use a mesh from the back to reinforce it? Should I v groove the crack and also file it out? Should I drill a hole at the end to arrest the crack as well? I just don't want this thing coming back

[Mills Marauder]

you will do more damage plastic welding that small of an area than good. if you bevel that crack on both sides with 180 grit paper and feather edge the surrounding area, clean with a prepsolve let dry and apply the epoxy to both sides you can leave the inside of the cover smoothed with a squeegee and sand and prime the outside with little to no filler.

[Stranger in the Black Sedan]

would i be okay drilling the end of the crack first too? if it would make me feel better? then sand back and bevel and fill?

[Mills Marauder]

duramix is fine. you dont want to make a large spot super rigid because it will show signs of stress later down the road.

[Mills Marauder]

sure you can do that to. im not against plastic welding its just got to be a perfect match of materials and everything must be just right to achieve a structural bond, the epoxy has a little more room for error before things dont go so good.