At some point in the past I'd managed to hook my front spoiler on a parking barrier, and had put a pretty bad rip in it. Finally decided to take a crack at fixing it.

Warning, this is going to sound like a Polyvance ad. I'm sure there are other vendors' systems for plastic repair. Their stuff was available from Amazon, so I went with it.

First challenge was figuring out what material(s) would actually work. There are no resin ID codes molded into the spoiler, and all of the plastic identification algorithms are a bit ambiguous RE: narrowing down the spoiler material non-destructively. So I bought a plastic welding kit from Polyvance and tried a bunch of their welding rods. Finally decided that the front spoiler is just polyurethane. So- I started by backing the crack with some 3M 06930 aluminum body repair tape and v-grooved the back of the crack:



Here is the welder (a glorified soldering iron) and the polyurethane rod- it has a very low melting point, you're basically pushing the rod through the head of the iron and flowing it into the crack.



It does bubble some, so there's a bit of porosity in the material (or maybe I had it too hot, entirely possible).



The material is more or less clear:



The rest of the spoiler is pretty badly scratched up, so 1) to fill some of the porosity in the crack repair, and 2) to fill a bunch of the deeper scratches along the length of the mid-spoiler, I used some 2-part epoxy flex filler (Polyvance 2000T)



Let it cure overnight (thought supposedly it's cured in 45 minutes) and sanded it to 220 grit:



There were still a few divots so I did a second skim cover, cured and re-sanded:



Then I sanded the whole thing to 220 grit, cleaned the whole thing with a tack cloth and then a spraydown with Super Prep, and sprayed a light coat of water based All-Seasons primer. (This is California, Polyvance won't sell the high-VOC stuff, their website is amusing on the subject- see under Product Description:

Post prime:


Then I shot a topcoat with their FlexTex low VOC stuff - 1:1 with reducer, 1.8 mm nozzle, 25 psi. Wear a respirator, it’s nasty fumey stuff, and requires mineral spirits for cleaning the gun.


Final product:



Hanging the spoiler in the air to ‘stress-test’ the repair. Pre-repair the whole end would have just ripped off.

 

dp

 

Great job Rob!

 

WOW that is a smooth job !!

 

That looks great. Your plastic welder probably was too hot which caused the bubbling but I'm glad the repair worked for you.

 

Yes, the rheostat on the welder is very loose and I accidentally turned the **** when dragging the iron's cord against it. So that was some of the bubbles....:ducking:

 

 

Looks great and no one will see any defects when you are going by at 100 miles per hour........or care. Great job!

 

Great job, Rob! That looks amazing.....

 

I mixed up a half dollar-sized blob on a plastic bag and let it cure for a couple of hours. Peels right off the baggie. Short answer is that it has plenty of strength in tension but it's not terribly flexible. Easily snapped it between two vice grips.

 

Nice repair Rob

 

Great job. Thanks for the tutorial.

 

I recall fixing one of the 86 type lips that was completely split through. I used a couple pieces of 22Ga aluminum backing plate, and countersunk screws from the front. Then I notch welded the front side, like this was done on the back, and used the belt sander to get it knocked down. Some of that matte wrinkle paint worked wonders to hide a lot of the scrapes. I bet that spoiler is still on the car.

 

Very nice, Rob! If you ever do it again or have to do touchup, I think you'd be happy with SEM Texture Spray to give it the orange peel texture. I had a can laying around from when I did the dash on my 84 and tried it on the scrapes on the bottom of the GTS' bumper. It blended in perfectly.

 

Thank you Rob, I have to fix my S3 spoiler, so I will keep this link in my to do list.