OK. Interesting paint mystery.

I just put a couple of coats of pricey automotive lacquer on my Estes PS2 "Sahara."

It fogged up a bit, which is something that happens in high humidity and not alarming. Drying in a hot place, or buffing, gets rid of the haze. I'm planning on polishing and buffing before the clear coat goes on anyway.

But look at the stripes in the haze on my Sahara. . . . pictures 1 and 2. Shiny, haze-free stripes, around the tube in two places, and leading forward from the fin.

What's happening there?

I know why what's happening is happening *there*, but not *why.*

The ring-shaped spots are where the plywood centering rings are that support the interior motor mount tube. The stripe leading up the tube is on the other side of the basswood strip you see inside, as seen in photo #3.

It is a long known "thing" that some adhesives shrink a bit as the dry or cure. This can cause a very, very slight drawing in and flattening of the body tube over an interior piece.

But given that, why is the haze avoiding those spots?

Attached Thumbnails

     

__________________
NAR #27085 - Oregon Rocketry - SAM

Just a guess, but could it be that the adhesive you used is seeping through the tube
Just Enough to cause the glossy sheen?

__________________
SAM #0031

Some background:

Model was built in late 2018.

Primed (Kilz) 2019.

Primer sanded off last month. More primer went on, and mostly sanded off.

Two or three coats of white paint. Waited a week. Another coat or two of white.

Wet sanded and compounded (polishing compound).

So, little chance of any adhesive working its way through!

Something *mechanical" is happening.

__________________
NAR #27085 - Oregon Rocketry - SAM

Oh. The only other explanation, then, is FM.

__________________
SAM #0031

No static at all.

__________________
Bill Eichelberger
NAR 79563

http://wallyum.blogspot.com/

I miss being SAM 0058

Build floor: Estes - Low Boom SST Semroc - Marauder, Shrike, SST Shuttle

In paint: Canaroc - Starfighter Scorpion Centuri - Mini Dactyl Estes - F-22 Air Superiority Fighter, Multi-Roc, Solar Sailer II, Xarconian Cruiser Semroc - Cyber III

Ready to fly: Estes - Solar Sailer II Semroc - Earmark

Maybe not static, but that steely grapefruit wine might make things fuzzy, Dan.

__________________
I love sanding.

"The girls don't seem to care..."


Good stuff, however I was thinking more along the lines of 'F****** Magic'.

__________________
SAM #0031

The fogged areas are where places on the tube got colder from the sprayed paint and allowed moisture to condense from the air and form on the surface of the paint.

My guess is that more than likely, the areas where the glue is are denser. Therefore, it took 'more' cooling to get them cold enough to condense moisture. In your case, those areas did not get quite cold enough to condense enough moisture to fog the paint.

I stuff the inside of my body tubes with paper towels or whatever to 'insulate' them somewhat. Even though it is on the inside, it helps prevent the tube from getting so cold as to condense moisture out of the air. Well, at least it helps. And here in the south, we need all the help we can get to fight moisture and humidity. It REALLY affects spray painting big time.

Earl

__________________
Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

I think we have a winner.

__________________
I love sanding.

Interesting! That sounds reasonable.

It is getting sunny. I think I will relocate the parts up to my balcony.

__________________
NAR #27085 - Oregon Rocketry - SAM