Paint Blisters/Fuel Tank Rivets

[rv9av8tr]

My QB wings are of the same vintage, 2006 and both sides, top and bottom blistered like crazy after a year. I was so pissed!! None of the blisters showed any signs of fuel staining, so was strictly internal vapor pressure delaminating the paint. I ended up sanding the paint down to bare metal all along the rib / rivet lines. Then filled the rivet tops with wet micro balloons, laid a ply of fiberglass strip, then dry micro balloons over that. Sanded and filled, no more blisters.

[simatos]

Holy a word I cannot use
**** paint job was 10 grand
very disappointing all around. Im this close to flying the darn thing. Guess Im gonna have to add blister repair to the never ending list. Thanks for the info. I hadn't thought about your fix. You did it with the wings on, is that right??
Thx Gary

[bret]

Originally Posted by bret

Just trolling around the threads I cam across some one on the 8 sight that has noticed an oil type film around the skins at joints and rivets, apparently they coated the QBs with something for the ocean voyage. I never notice this before, but last week I epoxy primer-ed, wet blocked and left to cure. yesterday I go out to the garage and at the tank seam there was a 1/4" wet line along the seam, look like some type of oil, none of the rivets had this and maybe because I did the Loctite 290 thing. But any way I wiped with grease and wax remover and it did not come back. Painting tomorrow and hope it comes out well. Paint Blisters,Fuel vapors, uncured primer paint thinners, OIL?

Just wanted to do an update and add data on the green Loctite trick, over one year with fuel in the tanks and no problems yet, the paint was mechanical etch with maroon scotch bright pads, epoxy primer, 360 wet sand and then base clear coat, fingers crossed. (above post was from 2012)

[airguy]

I've got about a half-dozen blisters forming on my left wing inboard tank, at 40-ish hours and 4 months after paint. Very small but definitely vapor blisters, all in one cluster near the rear baffle at one internal rib. I'll wait a bit to see if any others pop up before doing anything about it, probably this summer.

[DanH]

The last blister survey was circa 2009. It would be interesting to gather fresh data. If you have blisters, and would like to answer a few survey questions, please send a private email.

[PilotjohnS]

Originally Posted by airguy

I've got about a half-dozen blisters forming on my left wing inboard tank, at 40-ish hours and 4 months after paint. Very small but definitely vapor blisters, all in one cluster near the rear baffle at one internal rib. I'll wait a bit to see if any others pop up before doing anything about it, probably this summer.

Greg, Curious if you had used ?Tank dies? on fuel tanks?

[airguy]

Originally Posted by PilotjohnS

Greg, Curious if you had used ?Tank dies? on fuel tanks?

I did, yes, as that was considered the current vogue thing to do at the time I was building my tanks. I used the wet fay-sealing method on all my rivets as well.

[rv9av8tr]

Originally Posted by simatos

Holy a word I cannot use
**** paint job was 10 grand
very disappointing all around. Im this close to flying the darn thing. Guess Im gonna have to add blister repair to the never ending list. Thanks for the info. I hadn't thought about your fix. You did it with the wings on, is that right??
Thx Gary

I did it with the wings on. It was a PITA but I?m happy with the outcome.

[simatos]

Thank you guys, food for thought. Would sure like to avoid pulling the tanks

[dtw_rv6]

Here is an interesting wrinkle on the blister phenomena - My tanks were built 10 years ago, and I only had two minor weeps that I finally made go away with loctite. The tanks have been unpainted their entire life.

Last spring I wrapped them with vinyl along with the wings. The wings are holding up fine except for the tanks - I'm getting blisters over many rivets. I've cut a few open to find fuel pooled inside. Seems like the vapors are escaping where liquid cannot. I've never used anything but proseal (and a few drops of loctite) on the tanks.

Don