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Fuel Tank + Proseal

Palamedes

Well Known Member
How much proseal should I prepare when doing the tank? I have everything ready to go, but want to get a rough idea of how much of this stuff I should mix up.

Also, what is the suggested method of application? Would using a cake decorator squeeze tube/baggy (or just a ziplock bag with a hole) be the best way? etc..

Suggestions welcome =)
 
I made batches in the 40 gram and 10 gram sizes pretty often. After a bit I kind of knew how much I wanted.

I applied mine with popsicle sticks and later, for the type A stuff, a syringe. Both worked well. Other people used pneumatic tools and all sorts of things. I don't think it matters; use what's comfortable.

I did put a thin layer on both surfaces.

Dave
 
Here is everything you need.

IMG_8019-M.jpg


The syringe was obtained from a feed store for $2. The plastic knife from a local fast food restaurant and the stir stick from the local coffee shop. I used a toothpick to pre-apply proseal to the dimpled skin under the rivet heads. Practically free.

Make up just enough to fill about half of the syringe. The proseal won't set up and get stiff until about an hour. Lay down a bead with the syringe on the flanges of the ribs, then spread it out with the knife. The serrated edges of the knife act like a notched trowel and will put just the right amount down. Cleco in place and then come back in a day to rivet. After riveting, use the syringe to plop some over the rivet shop head. Also use the syringe to lay down a bead along side the ribs, and use the stir stick to make a nice fillet.

I went through more than 1 quart of the proseal for the tanks, so my advice is to get 2.
 
Proseal

I also used a feed store syringe. Price was right and matched my financial condition at the time (couple of years ago). Downside, proseal is quite viscous and the syringe was hard on my hands. Made a wider body flange where your fingers go out of aluminum which helped.

If I was doing it today, I'd look on eBay for a pneumatic proseal tool that you could mix and load by hand and apply pneumatically.
 
good times, good times

I used cheap 10 cc disposable syringes I got from the drug store or Amazon. For a mixing substrate I went to Home Depot and bought a single 12" x 12" white (smooth) ceramic tile. It's great for mixing and with a little MEK cleans up very easily. And lots of large, thick popsicle sticks you can get from Amazon or a craft store.

I used slightly more than a quart of proseal (total) for both tanks.
 
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For what its worth, I did the first tank using a ziploc bag. I stuffed the corner down in to the core of roll of paper towel roll then folded the bag around the outside of roll of paper towels to fill it. These were definitely one time use and still messy and I think alot of the sealant was wasted.

For the second tank I ended up scoring a pneumatic dispenser off ebay for $30. If I would have known how much cleaner and easier that made life, I probably would have waited to do the first tank until I had one of these available.

If you'd like you are more than welcome to use it for as long as need.
 
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I too bought a pneumatic set-up off of ebay and some spare tubes, both 2.5oz I think and 7.5 oz. I really liked the control of the pneumatic, and was surprised when I was done that I could just let the proseal cure in the plastic tubes and it would wipe out clean, so one or two tubes and tips was all I needed. Now mixing batches in a solo cup and packing them in the tubes was the messy part, but after all the horror stories of Proseal getting everywhere, I was ready for a mess and worked with multiple gloves and such, but overall it wasn't bad. I also found the pneumatic easy to go back and encapsulate the tails on the rivets after they were set.

Just my $.02
 
Search for: SEMCO Sealant Gun with 6 oz and 2.5 oz retainers Aircraft tools

Here's one, but they make one that doesn't have the pistol grip that I think works better for tight spaces:
http://www.ebay.com/itm/Semco-Pneum...:g:Zi0AAOSwubRXJsNH&item=391446942941&vxp=mtr

Here's one without the grip, I used the 2.5 oz retainer a lot more than the 6 oz, but the 6 is nice for the bigger jobs.
http://www.ebay.com/itm/Excellent-S...025789?hash=item210e5ef87d:g:JlwAAOSw3mpXDtr8


Is the pneumatic dispenser just a caulk gun basically? Can you link one somewhere?
 
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Home made pneumatic

I made a pneumatic.
Buy some of the huge liquid nourishment syringes from a pharmacy or ranch supply. Buy a caulk gun from any big box store. Load the syringe with Proseal. Place it in a caulk gun and squeeze.
I used more tounge depressors and popsicle sticks than anything else.
For mixing I found hard plastic disposable cups worked best.
Buy a battery operated Harbor Fright digital scale for weighing.
 
I just used craft store popsicle sticks, messy but it got the job done--I tried the cake frosting bag method but it didn't work well for me. I ended up using 1 1/2 cans of Proseal via a combination of Rick Galati's seal, cleco, and set aside for a few days method and the traditional set when wet method.

I've got 111 hrs on the plane now and had one weeping rivet: left wing, 2nd inboard most top rivet on the T-1005 Tank attach bracket. I used the wicking green Loctite 290 with a slight vacuum repair method and so far so good after about 20 hrs or so.
 
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There's the "what you need" list, as mentioned before, and then there's the "make the job as easy as possible" list. I went with the later and ordered a used pneumatic sealant gun from Brown Tool. They have a package deal for VAF members which includes everything you need for $60 (item# SURP-VAF25OZ). I had them send both the 6 oz. and 2.5 oz. retainers for an extra $10 or so. Then order the appropriate extra tubes and nipples from them.
 
I will also vouch for the pneumatic sealant gun. Well worth the $60 that I paid for it and plenty of spare tubs and tips. Clean up consisted of throwing the tube away. I had zero mess on the actual tanks and feel much better not having a ton of extra proseal inside my tanks (just my opinion).

You can do it either way, just depends on how many gloves and acetone you want to go through cleaning up!
 
I will also vouch for the pneumatic sealant gun. Well worth the $60 that I paid for it and plenty of spare tubs and tips. Clean up consisted of throwing the tube away. I had zero mess on the actual tanks and feel much better not having a ton of extra proseal inside my tanks (just my opinion).

You can do it either way, just depends on how many gloves and acetone you want to go through cleaning up!

Pretty much sums up my experience as well. I also had every intention of fay sealing my tanks, but decided to try the wet set technique first. I had so little mess doing it wet that I did both tanks that way. Will do it the same on my next build as well 😊
 
Pretty much sums up my experience as well. I also had every intention of fay sealing my tanks, but decided to try the wet set technique first. I had so little mess doing it wet that I did both tanks that way. Will do it the same on my next build as well 😊

Conversely, I tried the let-it-set-up method and found it no less messy than wet-sealing.

I also just used popsicle sticks and lots of nitrile gloves. Tried the ziplock cake decorator method and found it was messier and wasted more sealant, too.

If I were to do something different on another build, I'd mask off parts of the tank that don't get sealant.
 
Fay sealing is not the opposite of wet setting

The method in the Van's build manual is "fay sealing", because the sealant is applied to faying surfaces. If you read Rick Galati's post, that's what he says as well.

The term does not refer to whether or not you let the sealant cure before riveting - that's a separate issue.
 
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