FL 96 Owner

I have a 96 with lots of broken plastic tabs on various parts. In looking through the forum I have seen several possible solutions and after reading through some of them I decided to try the Plastex kit (it's about $30 from Amazon). I repaired one small tab and then went on to a much bigger one. This is the courtesy light cover from my halo.

The first image shows the broken tab and the unbroken one I used as a template to re-make the broken one. Note that I got the clear plastic version of Plastex but it comes in black and other colors. Since this tab is totally hidden I didn't care that it would be rebuilt in clear instead of black.

The second image shows the dam I built out of the included heat sensitive molding bar they send with the kit. You heat it in hot water and once it softens up you mold it around the part you want to replicate. Note in this image that I put a piece of scotch tape on the outside of the part and rubbed it down hard so that if any of the liquid plastic leaked from the mold it would not damage the visible outside of the part.

I put the dry powder into the inside of the mold holding the mold tightly against the plastic part so no liquid would leak out when I applied it and then using the dropper supplied wet the dry powder completely with the liquid. One bad thing about the instructions that come with the Plastex kit is that they don't say now long to let it "cure". I even e-mailed them with that question and they never responded. So when I did my first small repair I let it cure overnight. The one shown here cured for two hours before I removed the mold and it appears to be totally hardened even though it was a fairly large repair - I may just let it sit overnight just to be sure all the liquid has dried out of the part.

The third image shows the completed tab on the left (clear) with the existing tab on the right (black). It's hard to see but when I created the mold on the existing tab I added some strength to it before I removed the mold to make the new tab. I did that by adding some of the Plastex powder to build up the inside of the existing tab and added the liquid. I let this cure for only about 15 minutes before removing the mold and when I probed the surface with a toothpick point it was not totally hard but since it had the existing tab to support it I went on to build the replacement tab. You can see in the image the result (I had also applied some really soft and flexible weatherstripping to replace the factory ones that had degraded over time.

The last image shows the tab on an angle from the outside. You can see that it faithfully recreated the tab including the sharp angle that snaps into the housing. That is a result of being sure that when the molding compound is soft and pliable that I forced it completely around the existing tab insuring that it exactly matched the existing tab so the new one would be an exact duplicate.

What I am doing is replacing most of the high heat, low life bulbs in my car with low heat, long life LED's so hopefully I will never need to open each light housing ever again and that will eliminate any need to break tabs off in the future. But if I do I have a fix.

BTW, I got my LED bulbs at www.superbrightleds.com - their prices seem competitive, shipping is fast and cheap and when I got a DOA bulb they immediately shipped a replacement. You can't ask for more than that.

In all I think this Plastex stuff works fairly well and since I got some help with my problem from the forum I thought I would add my two cents so others know what I did and how I did it.

hcbph

Good to know. I bought one of the Plastex kits last fall in black. I have not had a chance to try it out yet on some of the broken tabs I need to do something on one day so it's good to know it works as described.

Well done and thanks for the review on the product.

Dt86

I also have used plastex and it works pretty well. It dries very hard and if you are using it on a surface you can see and have to paint, it is a pain to sand down.

ghlkal

Thanks for the info.

I have several tabs with screw holes that are broken off. Does it seem like the Plastex could be drilled after it cures?

Dt86

I haven't tried to but I don't see where that would be a problem.

FL 96 Owner

I posted my original thread on this topic back in April 2014 - you can see it on the forum. Now it's February, 2015 and I am in the process of putting two layers of soundproofing, new carpet, new leather seats (with foam) and all new weatherstrip on my 96 C4 - making the interior like new. To get to the tunnel side panels I had to remove the shifter console plate and the radio bezel. Sure enough the two tabs at the bottom of the radio bezel were all but gone. So here is how I fixed them - see my earlier post for info on the product I used - Plastex. This is what I started with - two broken tabs:




You can see the tab on the left broke off at it's base and had very little left outside the hole - the screw would not have anything to hold it. The one on the right was literally crumbling away and would not hold over time. The next step was to use the molding compound to make a mold - BUT I didn't have a complete tab to mold it from. So I searche around and found a measuring spoon that had just about the size I needed:




I used that to make my mold:




I found the hole was a bit small so I reheated the molding plastic and used another measuring spoon with a smaller hole forcing the soft plastic up through the smaller hold in the measuring spoon. I then put the cool mold in place under the first tab I wanted to rebuild and then put in the dry powder and saturated the dry powder with the liquid that creates the actual plastic:




As in my first post I have no idea how long to let it cure but I left these tabs cure for an hour and then carefully removed the mold leaving one of the tabs done (the one that had broken off at it's base). I didn't feel good about reinforcing that tab on one side so I turned the piece over and filled the cavites on the backs of both of the tabs with power. I didn't use a mold for this, just filled the cavity with powder and put on the liquid - they looked like this when I was done:




Once the dry powder was soaked with the liquid the backs looked like this as they cured (only one shown):




In the image above you can see one of the tabs finished (from the back side). I used the mold to fill in the other tab and after letting it cure for an hour removed the mold. After a little clean up with a fine file here is how the two tabs looked (from the front):




The one on the right in the image above was the one that broke off at the base. If you look closely you can see that I put a lot of power in the indentation at the base hoping to strengthen that area. And in both you can clearly see that I now have two full tabs that should work for many years in the future. I hope this helps you if you have broken tabs.

hcbph

I made some missing tabs for my 86:


Biggest thing is don't get the solvent anywhere you don't want it as it will turn the original black plastic white:


Overall it went well for me and things now bolt back together as they should.

kenpeindl

Great information to have. With it getting harder to find some of the plastic trim in good shape for the C4 something like this would be priceless.

Thanks for posting.

Crossed Flags Fan

This is great to know. Question - when you make the replaced tab, does it just "glue" itself to the larger part? Any prep work necessary to get them to adhere to each other?

Cliff Harris

I found that you really need to drown the area with the Plaster liquid so you get a good bond between the new and old plastic.

hcbph

I can only speak to what I did. I put the center bezel on a kitchen sink cutout, formica covered. I used shims and duct tape to put it down solid. Then I used some thin pieces of wood about the thickness of tongue depressors down to the formica to make a form where I was going to rebuild the tabs. I then filled the void with the plastic powder and soaked it down with the solvent (didn't work for me like the website showed). Let it sit a couple of hours, the stuff shrinks in volume so fill it up again and soak it down. Once it was solid and dry, I filed it flat with a file then used a die grinder to make the holes needed having marked the holes with a white pencil after a temporary reassemble of the parts.

Where I was fixing cracked screw holes, I used a die grinder to v-groove the crack then did basically the same thing to the groove except I put tape on the good side. What I found is don't scrimp, get very good tape to do the job and keep the solvent off the good side.

That's pretty much my experience.