Fuel tank sealant

[Rich Pulman]

I’ve reached the point where I’m building the fuel tanks for my RV8. The destructions call for “MC-236-B2” for the sealant. Unfortunately I can’t find that sealant in the aviation aisle at any of the local retailers, and it’s on back order at the mothership (Van’s aircraft) with no predicted date on availability. 

For the people here who do this stuff for a living, can you offer any suitable (or better) alternatives? Thanks.

[mrlupin]

Hi Rich,

Go for Pro-seal. It's what's inside most aircraft.

https://www.ppgaerospace.com/Products/Sealants/Fuel-Tank-Proven-Standards/P-S-890-Class-B-Fuel-Tank-Sealant.aspx

You can buy it in varying thickness and cure times. It's awful stuff to get off your hands so use gloves and maybe even barrier cream. I am pretty sure Aircraft Spruce And specialty will carry it.

Éric

[Maverick]

This is a common one we use on the Boeings. the "B" number is the working time in hours although that varies with temperature. The B2 is generally a bit runnier than the B1/2 but either one will work for you. Just make sure the surface is clean and dry and you really mix it well. It's a 2 part kit but really hard to mess up tbh.

Edit: as Éric said it's awful stuff to work with and is also a known carcinogen so wear good gloves!

 

https://www.aircraftspruce.com/catalog/appages/ps890.php

Edited March 19, 2022 by Maverick

[Rich Pulman]

Thanks guys. I am definitely not looking forward to the mess, and will take precautions. Luckily, it’s only two 21-gallon tanks. Can’t imagine what you professionals get to deal with in real size fuel tanks. My hat is off to you! 

[J.O.]

I recommend a respirator too. Manganese dioxide is a primary ingredient and that stuff is nasty. I wouldn’t put any of the other ingredients on my peanut butter sandwich either.

Edited March 25, 2022 by J.O.

[Rich Pulman]

9 hours ago, J.O. said:

I recommend a respirator too. Manganese dioxide is a primary ingredient and that stuff is nasty. I wouldn’t put any of the other ingredients on my peanut butter sandwich either.

I have one of these for the smelly jobs.

[J.O.]

Well done Rich! That's even better than a filter-based system, especially if you're using aviation paint that contains isocyanates or any product that contains chromium (aviation has several of them). No one can tell you how long a filter cartridge provides protection against that stuff. Forced air respiration eliminates that concern.

Edited March 25, 2022 by J.O.

[Kip Powick]

Rich,

By the look of your face, I would suggest you get outside and get some sunlight

Park the "hobby" for awhile.