Hi All
For those that have been advising me on my other two threads. I will be using much wetter passes from now on.
Do you advise for my first base pass and my first clear pass that it be a tack coat?
Could a tack coat promote orange peel?
I understand a tach coat to be useful in setting up a sticky surface before spraying wet coats, in order to reduce the chance of runs.

No idea why you would think starting with a dry coat will stop your dry coat problems. Seems counterproductive to me.

I am imagining that a tack coat is so thin that any dryness/orange peel will not project through the following wet coat.

No amount of discussion can replace experimentation on scrap.

A tack coat is generally used on a vertical surface to try to prevent sags and runs. The theory is put on a very light coat that is still wet, but thin. When you go back over it again it has had a bit of time to off gas and thicken up. This thickening is suppose to help hold the next thicker wetter coat that you put on top of it.

If you're not shooting at vertical substrates then you do not need to use this technique.

Hi Leo
I'm also shooting onto a vertical surface. That's why I was wondering about employing a tack coat. I practiced today on scrap and got some unexpected results. I set my inlet air to 29psi. I set my fan to 4", my distance to 4". I opened up my fluid to 4 full turns and then sprayed onto vinyl lacqur sealed MDF. No issues but hard to tell as the MDF texture shows through. No runs but is there OP? Can't tell. Doesn't look like it. I opened up the fluid 2 more turns and sprayed onto MDF again. Seemed a tiny bit smoother and again, no apparent issues. So I decided to spray onto some smooth plywood using the latter settings. Interestingly I started getting the grainy texture again, like dry overspray. Maybe the untreated plywood immediately soaked up the lacquer, drying it too fast. Don't know. I think this is why I've never been interested in testing on scrap. I'd rather stick to prepped guitar bodies and then resand them when things don't work out. But I am happy about the extra fluid output and no runs. I've been running my gun at only 2 full turns of fluid output.

If you are spraying vinyl sealer then that's to be expected. Even out of my Kremlin AAA it's hard to get a smooth finish with vinyl sealer. Seems to be the nature of that beast. I use MLC products so it could be entirely different.

If you are getting this with lacquer then there is still more figuring out to do.

There was no vinyl sealer on the plywood. The vinyl sealer was on the MDF, which did not have the grainy issue.

Most lacquer thinners are reconstituted junk.
Not really good for thinning high end finishes.
I switched to auto grade urethane reducer
in place of lacquer thinner years ago at the
advice of a paint chemist at a auto paint mfg.
It has worked a lot better than the lacquer.
And I can get it in really slow grades.

Hi Jim, any recommended brands?

I really haven't noticed a difference on
the different brands so I buy the off brand
that my car paint store sells.
I pay $25.00 a gallon but some of the
major brands are more than twice that.
It's cheaper for the 5 gal.