Filling Large Gap in Plastic

[Doms]

I’ll preface this by saying I have never worked with plastics. I know a little bit about different types and whatever else, but not my wheel house.

I have 2001 VW Jetta that someone retrofit some HID projectors into at some point in the past. I was never really thrilled with the job they did on sealing up the back of the headlight housing or the way some of the wiring was done, but it’s my commuter car and I never really cared enough to change it. I have the car in the garage right now to fix a few little things and decided to refinish my headlights as they were beginning to yellow. While they are out I decided to take a look at projector install.

To accommodate the size of the projectors, the original VW dust covers were hacked up, and then what looks like a universal cover was fixed in place with copious amounts of silicon. This is how these pieces fit together (silicon obviously removed)





As you can see, the gap is pretty big. What can I do to fill it other than silicone?

I don’t think fibreglass is the best option with it being plastic and all but I have worked with it is the past and it could be done.

A friend suggested possibly using some aluminum to shape a filler piece which would rivet to both of my existing pieces. I haven’t looked at this since he mentioned it to see how that would work out, but it’s probably another possibility.

Do I have options for plastic welding? Is there some sort of plastic filler I could use to build up and then eventually fuse these two parts? Like tig but with plastic?

Anything better that I am complete overlooking? I don’t need it to look like a factory part, but I would like it to be better than it was.

Thanks.

 

[corn chip]

maybe find some oe units from a salvage yard and return it to stock ?
im sure plastic welding is feasable but that looks like many hours of work and a half decent plastic airless welder is near $200

 

[ez-duzit]

Replace them.

 

[Doms]

maybe find some oe units from a salvage yard and return it to stock ?
im sure plastic welding is feasable but that looks like many hours of work and a half decent plastic airless welder is near $200

That was the original plan. Figured I would look into a low cost option to fix these if there was one. Wrecker had one car, but the headlights were trash. A new set off RockAuto isn’t ridiculous though.

 

[gearhead1]

Plastic welder option:

80 Watt Iron Plastic Welding Kit

Amazing deals on this 80 Watt Iron Plastic Welding Kit at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Plastic welding rods:

Plastic Welding Rods, 50 Pc.

Amazing deals on this 50Pc Plastic Welding Rods at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

 

[gearhead1]

I use a lot of epoxy with support material when repairing plastic parts. Support strips are usually strips of sheet metal, wires, or rods.

 

[welder4956]

I used some epoxy from this company to repair a plastic bumper and it worked very well. Your headlight housing is very likely a different type of plastic than my bumper, but they seem to have a product for either epoxy repair or plastic welding of most types of plastic.

https://www.polyvance.com/PlastiFix-Grille-Repair/

 

[Doms]

I use a lot of epoxy with support material when repairing plastic parts. Support strips are usually strips of sheet metal, wires, or rods.

Thanks, that looks likes a reasonably priced option. I think that’s what I am after. I was thinking I would use some stainless wire that I have kicking around to affix the two parts and form a skeleton by melting an end into each piece.

 

[Doms]

I used some epoxy from this company to repair a plastic bumper and it worked very well. Your headlight housing is very likely a different type of plastic than my bumper, but they seem to have a product for either epoxy repair or plastic welding of most types of plastic.

https://www.polyvance.com/PlastiFix-Grille-Repair/

That looks like it would work too but unfortunately it looks like it isn’t compatible with polypropylene which is what I have.

 

[NYBODYMAN]

As others have already said, I would find used OE or get some aftermarket replacements. I hate to say it but just about no matter how well you seal those up they will leak and have condensation in them at some point.

 

[Modern Garage]

Anything can be fixed - some things maybe shouldn't be. You said it's apart to clean the yellowed lenses so I think now's the time to kill two birds with one stone. In my shop I always explained to customers that the headlight polish job lasts a couple of years while a new headlight assy stays clear for at least five to ten yrs. More money but lots of time to amortize the cost. Here's your chance to put in new assys and enjoy the better visibility especially now with shorter days and longer nights.
As always, my opinion is worth every penny paid for it...

 

[welder4956]

That looks like it would work too but unfortunately it looks like it isn’t compatible with polypropylene which is what I have.

Yes, you will need a plastic welder and filler rod for polypropylene.

 

[welder4956]

Anything can be fixed - some things maybe shouldn't be. You said it's apart to clean the yellowed lenses so I think now's the time to kill two birds with one stone. In my shop I always explained to customers that the headlight polish job lasts a couple of years while a new headlight assy stays clear for at least five to ten yrs. More money but lots of time to amortize the cost. Here's your chance to put in new assys and enjoy the better visibility especially now with shorter days and longer nights.
As always, my opinion is worth every penny paid for it...

Good point. I squeezed a couple of years out of the lenses on my Montero, but wound up replacing them eventually. If you replace them now, you won't have to redo them in a couple of years. The hack job on the buckets is just more justification to replace them.