Mr. Surfacer 1200: the odd bubble

Dukat, S.G. · Post by **Dukat, S.G.** » Sat Aug 09, 2008 5:26 pm

All,

First, my apologies if this has been covered before. I looked and looked but didn't find anything in the archives about it.

I really dig Mr. Surfacer 1.2k. Wonderful stuff, really.

However, I sometimes notice pecularities when I use it. On a heavily-paneled model -- think the wings of a Klingon Bird-of-Prey -- I'll get a handful of 1-2mm long bubbles in recessed areas, particularly near sharp-edged raised panels.

What are these, and what causes them? This rarely happens with light coats (and I do mean light), but the model I'm working with is so small that, to get complete coverage, I almost can't help but to spray enough for a couple of the bubbles to show up.

Kylwell · Post by **Kylwell** » Sat Aug 09, 2008 7:07 pm

Er... I'm @ a loss. I'll have to experiment to see if I can duplicate the results. Have you tried thinning with Mr. Color Leveling Thinner?

Dukat, S.G. · Post by **Dukat, S.G.** » Sat Aug 09, 2008 8:04 pm

Kylwell wrote:Er... I'm @ a loss. I'll have to experiment to see if I can duplicate the results. Have you tried thinning with Mr. Color Leveling Thinner?

I've not, but my apologies: I was using a Mr. Surfacer 1200 spray can. I should've been clear about that from the get-go

I should also note that these "bubbles" are a minor problem at best. They can usually be "deflated" (more like flattened out) with a toothpick; and if things get too out of hand, I can always eliminate them with denatured alcohol.

Still, as I said, they are a curiosity. I wouldn't be surprised if they're a result of spraying in high humidity; I live just outside Charlotte, NC, and this area's infamous for its humid, "breeze? LOL! What's that?!" summers.

Kylwell · Post by **Kylwell** » Sat Aug 09, 2008 11:16 pm

Ah, yes that might well be the issue.

And would be tough to duplicate here in the land of 25% humidity.

Post by **TER-OR** » Sun Aug 10, 2008 8:52 pm

I've seen it.
What I think is happening in a recessed area is the surface tension is a bit high, and the corners trap just a tiny amount of air. When the tension does its thing, the bubble coalesces via gravity or capillary action from a ring to a single spheroid.

Now I usually wipe my pieces down with some PolyScale Plastic Prep and it makes a big difference. When I forget, I see a big difference.

Balok · Post by **Balok** » Tue Sep 02, 2008 4:41 pm

Huh... I know in our woodworking shop we never put a newly stained or finished piece out in the direct sun. It can heat up the wood and send gas out that causes spotting on the surface. I wonder if resin might outgas when warming in sunlight. I realize you didn't say you set in in the sun or that it was resin. Just my prolly faulty 2 cents.