I got no input into what went wrong, but just wanted to tell you that I feel for ya.  Sorry it didn't go as planned.

10 hours ago, Patcon said:

https://www.chevelles.com/threads/nason-primer-sealer.344661/

This might be an apt description

"looks sandy"

Based on the comments on the Chevelle website, there is a least anecdotal evidence that this product degrades over time.  The problem, of course, is that 'over time' doesn't mean how long since date of purchase, but instead how long since date of manufacture.  And the degradation process might depend on the storage conditions.  A call to the manufacturer's support line might provide some better insights or guidance.  

Your side experiment with the spare piece of sheet metal will probably* indicate whether your particular batch is flawed (* but not necessarily, because the spraying conditions won't match the conditions that existed within your indoor booth re temp and humidity).  Regardless of that outcome, I think that the safest route would be to write off what you have left and buy new.  Unfortunately, the law of paint system mix-and-match says that you should go with the same manufacturer again, so that all of your layers are Nason. 

The comments on the Chevelle website provide some useful thoughts on how to determine whether the new batch is also flawed.  Maybe there is more/better guidance available on other paint-and-restoration websites.  Also, the manufacturer may have their own guidance for pre-application checks on their product. 

I had a similar outcome with a vinyl paint that I applied to a Z upholstery panel.  Fixing the bad result was a PIA... but it was successful.

Crappy way to start the holidays.

I made a test panel today. Pulled an old junk hood out of the yard. Covered in green funk.

Scrubbed it with warm soapy water, degrease, wet sand at 600, then sealer.

Still have some funk in the sealer but maybe not as much

So I spent over an hour at finishmasters today. The general consensus is the sealer wasn't mixed enough but we can't account for the specs. He did some testing on the can but it didn't show a problem. It's possible the catalyst is going bad. Either way I'm not going to use any more of the sealer going forward. I will use white base coat like I originally did. The bad news is all of the white sealer needs to come off. It's not very thick but it's hard! I've already cut through in some areas and my blocking is already ruined in many areas. So I won't have a car ready for Zcon this year 😞

I have pushed pretty hard this fall to get the car ready for paint and now I have 60-100 hours of sanding to get back to GO. Then I will need to reprime, block, retape, rebuild the booth, etc.

Pretty demoralizing...

37 minutes ago, Patcon said:

Pretty demoralizing...

Stay strong.  It will all work out.

12 hours ago, Patcon said:

So I won't have a car ready for Zcon this year 😞

So sorry for the issues and frustrations you are going through Charles! I know you were making every effort to get Lily finished in time for Birmingham. It may still happen!

My Christmas wish for you is that everything goes smoothly from here onward. You've paid enough "dues" to the Z gods for the things that went south.

It will take a while for the sting of this to diminish, but you know Lily WILL BE beautifully finished. You won't accept anything less.

On 12/23/2021 at 3:02 AM, Patcon said:

I always have some trash in my paint no matter how hard I try

Just a thought.. could it come from lose (rusty) dust from a compressor tank?  Is there a airfilter on the system? 

I also can feel your pain.. i once had to paint a bike (motorbike) and i had terrible problems with silicone in the paint... after 4 ! times i was happy with the result... pfff... 4 x high gloss black..

Congratulations.. you have 30 followers! must give you a extra boost to plow on!

Have you asked the boys on autobody101.com? Got to ask, are you filtering the sealer through a 50 micron mesh cone filter into the cup? Do you have dry staticy conditions at the moment that could be attracting trash ?  A ground cable to the frame and a final alcohol wipe can help.

I have had so many problems with sealers that I just don't use them anymore, high build urethane primer sanded to 800 then colour coat on top of that.  I feel for you man, get Cody in there and put a block sander in his hands.

3 hours ago, dutchzcarguy said:

Just a thought.. could it come from lose (rusty) dust from a compressor tank?  Is there a airfilter on the system? 

I also can feel your pain.. i once had to paint a bike (motorbike) and i had terrible problems with silicone in the paint... after 4 ! times i was happy with the result... pfff... 4 x high gloss black..

I don't think air could be an issue. I have a very high quality redundant air filtration system.

1 hour ago, grannyknot said:

Have you asked the boys on autobody101.com? Got to ask, are you filtering the sealer through a 50 micron mesh cone filter into the cup? Do you have dry staticy conditions at the moment that could be attracting trash ?  A ground cable to the frame and a final alcohol wipe can help.

I have had so many problems with sealers that I just don't use them anymore, high build urethane primer sanded to 800 then colour coat on top of that.  I feel for you man, get Cody in there and put a block sander in his hands.

I am filtering through cone filters that are evidently 150-200 micron filters. I haven't seen 50 micron filters

It is possible that static is an issue sometimes. Although it had rained the day before and was fairly humid so static risk should have been low. I have not been onto Autobody 101 to ask. I guess that could be an option. At one time I did have a ground cable to the chassis but have not done it in a while. The alcohol wipe is a good idea.

I don't know that I will use sealer again after getting burned like this.

800 seems pretty fine?

2 hours ago, Patcon said:

I I don't know that I will use sealer again after getting burned like this.

800 seems pretty fine?

Charles, if I didn't live 2,289 miles away, I'd drop by and help you sand.

On 12/14/2021 at 7:08 PM, grannyknot said:

Charles, have you heard about these Acrylic Linear sanding blocks? There is a number of vids on Utube, very impressive how flat they get your panels, I just ordered the the 12" set and will try them out on the 240z this winter.

https://linearblockingtools.com/our-products

Chris,

So I was shopping for some new blocks, since I will have to reblock the whole car. They don't have a complete sets but they do have individual blocks.

If you were going to buy one flexible block and one straight block, what lengths would you want and why?

The 18" flexible would be great for the gentle curves around the edges of the roof and back fenders, 12" flex would be good just about anywhere as would a 12" straight. It would also be nice to have a 6" straight for the tight curves and edges of the front fenders and hood.  I mentioned I ordered 2 12"x12" 3/16th acrylic sheets, when they arrive I'm going to make a 12" flex, a 12" straight, 6" straight and bunch of 1"&2" blocks of various lengths.   The 18" would be nice but I think you could do everything with a couple of 12"'s and a 6" block of hardwood.