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Tank Sealant.. About to get messy (starting tanks)

Daniel S.

Well Known Member
Morning guys-
I'm starting on my fuel tanks this week (WoooHooo!!!)... I'm kind of curiuos as to the "best" brand of "ProSeal". I've been shopping around for a bit now & I'm seeing that there are a few different brands, prices and I'd assume grades for what we all call pro-seal (flame-master, 3M AC-tech, etc.). With that said, Is there any preference among my fellow builders here? I know the end product usually comes down to craftsmanship while building the tanks but I want to start with the best know products.. Thanks all!!!
 
Tank Sealant

Daniel,

I used the VANS grade. It's made by FlameMaster. As long as it's mixed in the proper proportions it seems to work fine. Yes, it is messy but with a little planning the work goes by fast. Get an apron, a box of gloves, heavy duty paper towels, and MEK. Oh, did I mention I need another quart of sealant? I wasted quiet a bit starting and stopping and cleaning up. I had as much time in my left tank as I did in the whole left wing.

Also, I meant to send you some pictures of my flop tube installation but forgot. Good luck.

Chuck
 
Daniel, my brother...

You can't go on without reading this document written by our very own Paul Trotter.


Paul is a great guy and has compiled quite an intensive document on the subject.

Hope this helps!

;) CJ
 
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Just wanted to throw one more quick tip out there to ya before you get started.

Go to the Feed Supply Store and get some Horse Syringes, the big fat ones, after you have mixed up a batch of proseal fill the syringe and it makes it far less mess and application is so simple.

-david
 
CJ- Thank you for the article! It definately clarifies the "classes" of sealant(s), something I was a bit confused about but now I see the light..

It seems most are just going with the Flame-Master supplied by van's. I wonder how many folks have used the PPG or the 3m AC&T Brand sealants. With the big names out there, I'd personally tend to lean twords the AC&T brand or PPG band rather than the Flame Master... But MIL-Spec is MIL-Spec if directions are followed properly. Hmmm! Still a debate for me though :confused:
 
I went with what Van's recommends. I suspect the problem people have with their fuel tanks is rarely related to the sealant and more related to the technique and amount used. There's no reason to make the inside of your tanks pretty as I've seen in some builder logs. I used a quart of ProSeal (or whatever it actually was) on each tank -- way more than one would expect.

I was guided by George Orndorff who drilled into us that (a) ProSeal is cheap; use plenty and (2) If you look at the part and say, "this CAN'T leak," it won't. But if you look at it and say, "I don't think this will leak," it probably will.
 
Thank you Bob. I promise to have the nastiest looking tanks (on the inside). :D I was planning on using 2 quarts. I NEVER want to worry if these things will spring a leak.
 
One note. Make sure that you figure out the vent line before installing the end ribs. This isn't that well spelled out in the instructions. I put one on before I realized I shouldn't have. One you can deal with, both would be very difficult.
 
CJ- Thank you for the article! It definately clarifies the "classes" of sealant(s), something I was a bit confused about but now I see the light..

It seems most are just going with the Flame-Master supplied by van's. I wonder how many folks have used the PPG or the 3m AC&T Brand sealants. With the big names out there, I'd personally tend to lean twords the AC&T brand or PPG band rather than the Flame Master... But MIL-Spec is MIL-Spec if directions are followed properly. Hmmm! Still a debate for me though :confused:

You are welcome!

Yes, MIL-Spec is MIL-Spec is MIL-Spec. Use them interchangeably.

Have fun with that pro-seal!!!

:) CJ
 
For minor repairs or "other" uses any of them will do, if I was doing a set of tanks I would stick with the PRC-Desoto/PPG stuff.
 
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Sorry to see this Bob!!! :(

An addtional thought I recently had concerning sealing my tanks was to get an additional quart of class A or C sealant & brush the thinner sealant over the cured sealant right before installing the rear baffle. This would serve as an addtional insurance policy against any possible "fine" leaks... Probably overkill & not needed But I like overkill :eek:

Any thought on this idea?
 
Be sure to read...

everything on this forum written by Rick Galati (RICKRV6, I believe) about sealing tanks. All you need to know--and they won't leak when you finish. :) Be sure to let them cure thoroughly before you pressure test.
 
I agree

I agree with Jarvis, read Ricks post and follow carefully. I have some experience with proseal on kc135's, so doing my tanks were not as bad as one would think. Kudos to Rick, if you follow him you will have a good set of tanks. Only thing I would like to add is this: More is not always better. Applying it properly is way better. Using Ricks method, I did actually use more than Van's says it will take, so plan on two cans, one other thing I did as others was to use proseal instead of the cork gasket supplied with the kit. Make sure you have enough clecoes before you start, and Cleco every hole. Investing in a semco applicator and disposible tubes will make life much easier and enable better control for applying the sealant. Good luck and you will soon be the proud owner of two leak free tanks.

Bird
 
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Thank you Bob. I promise to have the nastiest looking tanks (on the inside). :D I was planning on using 2 quarts. I NEVER want to worry if these things will spring a leak.

You don't HAVE to be messy when using a lot of proseal. I spread mine with acid brushes with the bristles trimmed to 1/4" -3/8". I found that "painting" on the sealant with these was way less messy that trying to spread with a tongue depressor. I spread a 1/32" to 1/16" thick stripe on the skin, and the same on the ribs.
FP02102012A0004V.jpg


I also used the same brush to make the fillets. This result is with little to no cleanup.
FP02102012A0004X.jpg


On the left tank, I had to clean sealant (I used MEK) off the skin outboard of the outboard rib to prevent interference with the joint plate. On the right tank, while the rib was installed dry, I masked the skin, which made the cleanup MUCH easier; after installing the rib, making the fillet, and encapsulating the rivet heads, just peel off the tape and you're done.
FP18102012A00035.jpg


I used 60cc syringes from drugstore.com to apply the 3/16" beads for baffle installtion, per the instructions. It took a couple of loads of sealant per baffle. The masking tape is to ease the cleaning after forming the fillet between the baffle flange and skin.
FP29102012A000PH.jpg


LOTS of proseal, but it came out nice and neat.
FP29102012A000PJ.jpg


I used about 3/4 can of sealant per tank. No leaks on the left tank, and I haven't yet tested the right one.
 
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