Clam shells

[graham]

Hi guys.

Sometimes the damage causes a piece of the glass to pop out, a thin "ear" shaped piece a bit like a clam shell.

I know it need to be filled with pit filler first before repair, but is it ok to pit fill and cure as it is, or should I score the area first with the tapered bur to give the pit resin something to grip onto? (Obviously I will remove any loose shards etc first if necessary)

I think that scoring will leave an uglier finish maybe, but not scoring may mean the resin may pop out over time?

Thanks

[Brent Deines]

If a high quality acid based resin is used no scoring is necessary. The acid lightly etches the glass and I have never seen a pit "pop" out of one of my repairs, regardless of how many years it has been since filled. That said, I have tested some resins that do not stick well at all, in some cases even flaking off the glass or coming out of the pit as the cured resin is being scraped flat.

Resin...all resin...will however age over time. How much it changes in appearance depends on the quality of the resin, how well the vehicle is cared for, climate, miles driven, etc. The larger the pit area the more noticeable the aging process will be.

[Nomad]

I usually score these, rough them up a little for a better bite from the resin. I have not found that this reduces the clarity or cosmetic appearance of the pit. Many times I will use a little regular repair resin so as to make sure that all the little marks are filled before putting pit resin into it. I usually tell the client that the pit is exposed to all the weather and sand and chemicals that are used in washing the car and using the washer spray so will deteriorate in a few years. If that happens just bring it back and I will replace the pit filler at no charge. If I see a repaired chip on a car I'm working on that needs the pit filler replaced I will usually do it at no charge, the customer really appreciates this. Next time they'll be more likely to come looking for me, at least I hope so. I think they do.