[BarryK]

Powder bill,
Here are the photos. There is a heavy industrial fallout coating on the panel but all I did was wipe with rag. Really need buffing but still looks good.
I have an 8 Pix camera and by the time I edited down to download I may have killed the pictures as I should not be allowed to use camera.

The paper is covering other companies paints that I was testing and there is labels so that why its covered.

[powderbill]

Barry,
Very interesting! This certainly does appear to be working much better than I would have predicted. You know what might be interesting as an experiment, next time you check it give a corner a real small little scribe line down to the primer, and then lets see if it starts to delaminate sometime in the future at the scribe, before any other failure mode is evident...just if you want to, of course.

Another thing I wonder is if a clear without UV absorber would also work...maybe you've hit upon a good test for UV absorbers in clears! ?

Well, Barry, you've definitely taught me something I wouldn't have expected here!

[BarryK]

Thats a great idea!

What I will do is with a flathead screw driver is X the whole area down to bare metal.
In 30 days I will do an adhesion test or chip test as I have been looking at a new piece of equipment in the paint magazine and this would be a good excuse to buy it.

Most important with the X is wonder how it will react for corrosion creeping?
Have we killed the Phosphate or weakened any other properties?

Corrosion test this way may be guess by-golly but I don't want to do a salt spray test and ruin the panel this soon.
Wish I had made more panels!

[crashtech]

Another two cents on the epoxy-UV thing. In the case of GM, as far as I know it was a matter of too little paint being applied, to save money and reduce VOC emissions. All epoxy primers are sensitive to UV to some degree. It's surprising to me that the black epoxies seem to hold up so much better. I know that I would NOT want to apply it as a topcoat in my shop, and have instead been using POR-15 Chassis Coat Black.

[BarryK]

Originally Posted by crashtech

It's surprising to me that the black epoxies seem to hold up so much better. I know that I would NOT want to apply it as a topcoat in my shop, and have instead been using POR-15 Chassis Coat Black.

************************************************** *
No surprise as black is made with carbon.

Your statement here shocks me as I'm in a 1000-1500 body shops a year and you never see a bodyshop use por.
This is a big item for the do it your selfer. (thats who they market.)

If you think its better than an epoxy, do your self a favor and spray a scrap panel with any black epoxy and another panel with por and set outside in sun.
Compared to the worst epoxy made, the epoxy will out last it at least 6-8 to one in time of chalking.
Your por will chalk in side of 1-3 weeks.

[crashtech]

Originally Posted by BarryK

************************************************** *
No surprise as black is made with carbon.

Your statement here shocks me as I'm in a 1000-1500 body shops a year and you never see a bodyshop use por.
This is a big item for the do it your selfer. (thats who they market.)

If you think its better than an epoxy, do your self a favor and spray a scrap panel with any black epoxy and another panel with por and set outside in sun.
Compared to the worst epoxy made, the epoxy will out last it at least 6-8 to one in time of chalking.
Your por will chalk in side of 1-3 weeks.

Well, I did not intend to be shocking or controversial. I have seen impressive results from POR-15 products. My personal belief is that shops tend not to use them because POR-15 product's slow cycle times are not easy to work into a production schedule. Or, maybe they are just ignorant.

Standard POR-15 does not contain any UV protectant, and will discolor quickly. Chassis Coat Black is NOT the same as regular POR-15. As to testing, you might say that there are several tests already in progress, and so far I have no reason to withdraw my recommendation.

[BarryK]

Controversial, no was not taken that way at all, its a subject I chose to leave a lone but when you said you owned a shop felt it should be brought up because your new.
Your happy with it, were happy with it.

[crashtech]

Well, I went ahead and introduced myself over in the Lounge. Forgive me if it's considered rude to just dive in!

As far as me thinking that something else might be better than epoxy as a topcoat, it seems like a no-brainer to me that epoxy was never intended to be used in the way guys are using it, no matter what pigment has been added. I'm sure that any paint chemist would agree with me that no matter what the anecdotal evidence is, it's just not advisable. I'm sure a lot of guys will think they can just sand it and paint the weathered epoxy when the time comes, when in reality it will likely have been damaged by UV whether it shows it bad or not, and will be WAY more likely to delaminate the topcoat in the future...

P.S. I don't own a shop. When I said "my", I meant where I work. Sorry.