e53 Bumpers-what plastic are they made of?

[omodos]

Sorry for stupid sounding question,but can someone shed some light on what exact type of plastic is used in the back part of the x5 bumpers? (please see pic) Guy at a hardware store was convinced that it would stick my pdc sensor&housing back to where it had become detached from the bumper.....checked out glues properties I used and says Bonds: Hard Plastics, Metal, Concrete, Glass, Ceramic, China, Acrylic, ABS, Vinyl, OVD Fiberglass, Wood, Styrene, Corian. Does not bond to Polyethylene or Polypropylene Plastics. Checked out what bumpers are made of in general online and there is good chance they maybe made of this type of plastic.....be a MASSIVE help if anyone has a bumper lying around and can tell me if it has any markings on the back of it like ABS or PPor PE?

[omodos]

Hmmm I think this, so assume the from bumper is the same, darn the plastic welder i bought to stick by pdc sensor housing back to the inside of the bumper aint gonna do the job.....

BMW X5 Rear Bumper Hitch Cover OEM 8 402 327 Pp Epdm Tx10 | BMW X5

[oldskewel]

Originally Posted by omodos

Hmmm I think this, so assume the from bumper is the same, darn the plastic welder i bought to stick by pdc sensor housing back to the inside of the bumper aint gonna do the job.....

You say it won't work because that plastic is not weldable, or that plastic is not compatible with your plastic welder kit?

[80stech]

I did mine last year and I think I just used loctite weld (like J-B but 15 min. set time). If I remember right it has a big surface area to stick to, but just make sure you rough-up and clean the surfaces.

[omodos]

Originally Posted by oldskewel

You say it won't work because that plastic is not weldable, or that plastic is not compatible with your plastic welder kit?

Thanks for reply...Nope doesnt weld this type of plastic to itself , to check what type of plastic it was I took off the tow point plug off the front bumper that I guess is the same material as the rest of the black part of the bumper it plugs into?....markings on back say made of PE+EPMD ( polyethylene+ethylene propylene diene monomer) , put a blob of the plastic weld i bought onto this part and next day I was able to just scrape it off with my fingernail....nutty things is this : I applied this mix on the pdc housing/mount the sits behind the bumper and forced as best possible back into the bumper yestrday and today the sensor+mount seems quite rigid when i touch it, so not sure what happened and it stuck?...I also tried stock silicon and again that just peels off this plastic...just curious what damn glue can hold this plastic to itself? the mount for the pdc seems to be part of the sensor and despite the pic showing indents for where you may think the bumper clips onto it I am sure it is not the case, its just attached by some fused plastic to the bumper at those 4 points.....

[oldskewel]

I don't completely understand, but it sounds like this "plastic weld" is actually a glue, with maybe some chemical reactions, but no thermal welding.

If I am right in this interpretation, and the plastic you'd like to weld does not need to be extremely strong, you might try actually welding it with a plastic welding kit that uses what looks like a soldering iron with a special tip and lower temperature (to melt without burning the plastic).

My understanding is that a critical aspect of making this welding work is for the weld filler material to be a near-identical match (type of plastic) to the pieces you're welding. Often the kits will come with plastic rods. So my suggestion, if you just need a little welding done, and you need a good match for the plastic, is to find a section of the bumper on the inside that is not critical, and shave it away and use that as the filler welding rod. It is probably much easier to do this than it is to identify the plastic and find matching welding rod.

Sorry I did not really understand your question. Hope this helps, though.

[omodos]

Originally Posted by oldskewel

I don't completely understand, but it sounds like this "plastic weld" is actually a glue, with maybe some chemical reactions, but no thermal welding.

If I am right in this interpretation, and the plastic you'd like to weld does not need to be extremely strong, you might try actually welding it with a plastic welding kit that uses what looks like a soldering iron with a special tip and lower temperature (to melt without burning the plastic).

My understanding is that a critical aspect of making this welding work is for the weld filler material to be a near-identical match (type of plastic) to the pieces you're welding. Often the kits will come with plastic rods. So my suggestion, if you just need a little welding done, and you need a good match for the plastic, is to find a section of the bumper on the inside that is not critical, and shave it away and use that as the filler welding rod. It is probably much easier to do this than it is to identify the plastic and find matching welding rod.

Sorry I did not really understand your question. Hope this helps, though.

No worries correct doesn't need to be super strong, basically see pic I posted to see what side needs bonding to what... the housing of the pdc sensor( smaller pic above or replacement part with 3m adh shown below ) came unstuck from the inside of the bumper (after a collison I had) so dropped bumper coated one side of housing with the plastic weld and pushed it against the inside of bumper so it sits true and pdc is where it is supposed to be..both bumper & pdc housing are the same black type of plastic.The plastic weld i got and tested (too late alas) simply scrapes off this type of plastic once dry...I am not going to go through trouble of removing bumper to get the sensor and housing again as it is somehow holding in place (even with the non-holding plastic weld)... I will take out the toe point plate so i can have a little access to the sensor/housing next to it in the bumper find a suitable glue put it in a syringe and squirt some in there and press sensor/housing against bumper n hope it holds or somehow wedge in there some foam polystyrene cut to side so as to keep it from moving if it comes loos.....again thanks for all the feedback

[upallnight]

Probably made with Teflon that's why nothing sticks to it. LOL

[omodos]

Originally Posted by upallnight

Probably made with Teflon that's why nothing sticks to it. LOL

hahahah Yup everything just peels off this type of plastic, think only fix is to heat weld or get shavings of the same type of plastic heat em and fuse to it as mentioned....either way not gonna fret over it anymore....the pdc & housing is sitting tight and after poking around through the toe plate hole (from where i can see and feel the sensor/housing) seems there is also a little tooth or clip in the bottom corner that has clipped the housing into place on the bumber (so in essence glue not required) and on the other end of the housing I know for sure that the flat plate sits under the polystyrene that sits in the bumper......I WISH had taken pics the night we removed so as to clear up the conundrum......IF anyone takes off a facelift e53 bumper will make my day for them to take pics of the pdc sensors so as to show how they sit in the bumper.....cheers to all