Aluminum Fuel Tank construction using Proseal - no welding or leak fixing

[Steve]

Proseal application suggestions:

http://www.experimentalaircraft.info/articles/aircraft-proseal.php

Wear gloves, throwaway cloths and a discard-able work surface

Best price usually found at Van's Aircraft

Consider using a lighter material - say .025 6061-T6 - rolling beads to stiffen and a baffle across the middle... Don't neglect to include a finger screen at the outlet, an AS&S item and you might like a quick drain too

This is what Robert S Hoover had to say about it:

http://bobhooversblog.blogspot.com/2006/12/av-yo-fuel-tank.html

Sam Buchanan made one and also placed in a new location on his XL:

http://home.hiwaay.net/~sbuc/legaleagleXL/tank.htm

BTW: Les Homan is flying an XL with the Alum/Proseal fus tank and running the Mikuni Dual carbs without a fuel pump - he has 50 hours on the setup without a glitch at this writing...

[grdev]

Proseal is great stuff, but nasty ,nasty to work with. Used it on two different planes, no problems at all.

[Sam Buchanan]

Proseal application suggestions:

http://www.experimentalaircraft.info/articles/aircraft-proseal.php

Wear gloves, throwaway cloths and a discard-able work surface

Best price usually found at Van's Aircraft

Consider using a lighter material - say .025 6061-T6 - rolling beads to stiffen and a baffle across the middle... Don't neglect to include a finger screen at the outlet, an AS&S item and you might like a quick drain too

This is what Robert S Hoover had to say about it:

http://bobhooversblog.blogspot.com/2006/12/av-yo-fuel-tank.html

Sam Buchanan made one and also placed in a new location on his XL:

http://home.hiwaay.net/~sbuc/legaleagleXL/tank.htm

BTW: Les Homan is flying an XL with the Alum/Proseal fus tank and running the Mikuni Dual carbs without a fuel pump - he has 50 hours on the setup without a glitch at this writing...

Good info from Bob Hoover but I strongly disagree with his suggestion to slosh the tank. Slosh can come loose and if it doesn't result in a forced landing it will eventually result in the tank being opened up and the slosh removed. A properly pro-sealed tank never needs slosh.

[grdev]

After I sealed the tanks with Proseal I put some MEK in the tank and turned it round and round and upside down. If you have any pin hole leaks they should seal. MEK is the only thing I found that would thin the Proseal.

[rockiedog2]

I agree with Sam about not sloshing. I had a Cherokee way back that had a fuel tank leak. Had it sloshed by the local mech who was known as highly compotent. Coupla days later it was leaking again. And all that loose slosh in the tank. Ended up buying a used tank from a salvage yard.
It's a definite bandaid. One time was enough for me.

[Hugh Sistrunk]

I built my alum tank using Bob Hoovers guidelines with the exception of sloshing the tank.  I pressure tested it (couple atmospheres), used soapy water and found no leaks after letting the tank sealant cure for 3 days.  Then I filled the tank with fuel and let sit full for 3 days - no leaks, so hopefully I am good to go...
I used a sealant called SEALPAK - SealPak Company Inc. , Wichita, Ks.  phone 316-942-6211..
Priced at about 60% of ProSeal and is used in the same ratio as ProSeal.  Seems to be the same formula as ProSeal now that the patent has run out the clock.  You can call them and they are very helpful.  They have it in a 2 hour working formula and a 4 hour.  I used the 2 hours stuff and felt pushed for time on a couple of occasions.  You will want to have all the parts fitted, drilled and cleco'd prior to starting.  I did my tank bottom corners and baffles on one batch, then the top on the next. etc...
All previous recommendations below apply to this sealant as well.  It gets on your clothes, it gets on your work area, on your hands.  Thankfully I resisted the urge to scratch my favorite places and pick my nose while I put the tank together - Yeah self control is a good thing here
When deciding the dimensions of my tank I used this formula and adjusted to get the gallons I needed.  Length X Width X Depth divided by 231 = GALLONS it will hold.
Sorry for the long post, and now you can see why I did not enjoy losing it on the first attempt.  Hope this helps some.

NightEagle
BlackHut Ops
CoonNeck, Texas

[weasel]

Make sure you do a good job on the tank riveting.  Proseal does NOT "fix" poor construction techniques.  I have seen some shoddy work that the builder thought proseal would fix.  Started leaking within 2 years of operation.

[grdev]

Using MEK before the Proseal  sets up isn't exactly the same as sloshing with some sort of sealer, it just thins out the proseal.. It uses capillary action to wick itself with the proseal into any possible minor leaks. It is actually recommended that you thin some proseal with MEK and brush it around all you rivet heads and joints. It won't work after the prosel has set up. After I brushed all my joints with the mixture I used a little, and  mean very little vacuum  on the filler neck to pull in and  seal any possible small voids in my flanges. Just sticking a vacuum cleaner on your tank will most likely collapse it.  Nothing ever in my tanks, 4 total, ever broke loose, as the MEK just evaporates leaving the proseal to cure. My original DE tanks are several years old now, and the Proseal is still flexible and the tanks don't leak
There are several web sites explain the procedure.

[grdev]

DE tank sealed with proseal in 2009