What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

RV-12 Firewall rivet sealant

08FATBOY

Member
First time post. I have a question about what type of sealant to use , fuel tank sealant or firewall sealant and is it required to cover all pulled rivets? Also, if covered, is their any thought about viberation causing rivets to loosen that might be masked by sealant, or just overthinking. Anxious to start on engine. Thanks for all input!




sn#120162
 
I used 3M Fire Barrier 2000+ on the firewall and to seal the pulled rivets. You need a fire retardant sealant here, not Pro-Seal. There is no reason to think that vibration would loosen a properly set rivet.
 
I used Hi temp RTV. You don't need to goop every rivet because the mandrel a plug them. Just plug everywhere you see daylight.
 
I used Hi temp RTV. You don't need to goop every rivet because the mandrel a plug them. Just plug everywhere you see daylight.

This is not correct if you are building E-LSA.
The KAI stipulates that you are to seal each rivet (along with the panel seams and other gaps).
A major reason is, regardless what you think, the blind rivets are not sealed.
Oil, etc., can and will pass through them.
High temp RTV is not a good choice of sealant because it is not fuel resistant.
 
I am building to E-LSA, and will cover all rivet heads. Plans show both fuel tank and firewall sealant which to use? Would appreciate any photos of firewalls as i am trying to make this as neet as possible. Thanks again!



SN#120162
 
I am building to E-LSA, and will cover all rivet heads. Plans show both fuel tank and firewall sealant which to use? Would appreciate any photos of firewalls as i am trying to make this as neet as possible. Thanks again!
SN#120162

Some fuel tank sealant is used in the joint between the vertical and horizontal sections of the firewall, as called out in the plans. Fire sealant is used generally where the fuselage skins met the firewall, and to seal the rivets and any other gaps. The plans tell you where to use it. This picture is from Tony Tessitore's build site. I'm sure he won't mind me posting a link here. If you want to see masterful workmanship, have a look through his collection of photos.

http://tonytessitore.smugmug.com/RV...010094_cSz8X5#!i=632922820&k=Db8dhkj&lb=1&s=A

I used masking tape to make neat little squares around each of the rivets before applying the sealant, but it still looks pretty ugly.
 
Last edited:
Here's the simple answer!

I have a question about what type of sealant to use , fuel tank sealant or firewall sealant and is it required to cover all pulled rivets?

Sorry Rod. Sometimes when you ask a simple question you don't always get a simple answer here on the form. The answer is use Pro Seal, otherwise known as FlameMaster. The same stuff you use to build your fuel tank. Here is the link for purchase.;)
http://www.vansaircraft.com/cgi-bin/store.cgi?ident=1364652651-232-576&browse=misc&product=proseal

Yes cover all Rivets or gaps that might let any fluids or exhaust gases into the cockpit. Neatness doesn't count.
There is a bit of a learning curve when it comes to ProSeal. If you want after you apply it you can try patting it down some with your finger. Put good old fashion spit on your finger before you touch the proseal to keep your finger from sticking to it.:p
 
Last edited:
Rod, welcome to the forum. When I put the goop (proseal) on the rivet heads I was concerned about slopping over. So I cut up a bunch of sticky labels into smaller pieces and punched them with a hole punch. Then centered the holes over the rivets. Put on the proseal, waited for it to partially cure, then pulled off the labels. Yeah, I know, neatness doesn't count, but sometimes my OCD just gets the best of me.:eek:

John
 
Instead of punching a bunch of holes in sticky tape (I couldn't punch out consistently round holes!), I just used some lengths of old electrician's tape (long runs crossed by short stub pieces) to "frame" each of the rivets. A little dab o' ProSeal on each rivet head, smoothed out with a wet fingertip, let it set a bit, and tear off the tape. VIOLA -- a series of neat, squarish, well-sealed rivet heads. Tape is your friend when working with the gooey stuff. :)
 
Scott,

I can't challenge the position that the KAI specifies gas tank sealer, but it seems an inconvenient choice for the following reasons: the rivets are tight enough to prevent engine compartment gases from getting into the cockpit, HI tempo RTV gives a convenient and durable seal for gaps, and there is no long term exposure to gasoline that would degrade the RTV. How does the gas tank sealant hold up to the engine compartment temperature?

It just seems Hi Temp RTV is a convenient and adequate alternative Vans may want to consider.

Rich
 
Flame test posts

Take a look at Dan Horton's posts regarding his flame tests. Date was around 13 June 2011. Takes a while to read, but very informative.

I've about given up on my "neatness score" with Proseal and Flamemaster, but here's what I ended up doing for sealing the shop heads of pulled rivets...

Get a syringe. Use a drill bit and slow drill speed to open up the hole so the material will flow thru easier. Otherwise its VERY hard to extrude the material as it begins to set up.

I used a short piece of 1/4" OD plastic tube and widened one end by forcing it onto an awl and heating it with a heat gun. This way the tube fits over the end of the pulled shop heads with a little room the spare. Install the non-expanded end of the tube onto your syringe.

The syringe can be loaded from the rear using a popsicle stick. Put on your nitrile gloves, loader 'er up, insert the plunger and go to work. Place the expanded end of the plastic tube over the shop head, extrude enough goo till you see it coming out around the base of the rivet. Spin the syringe once around to be sure sealent is applied all the way around the base, then pull it straight off and move to the next one. After a bit of practive, I was able to "seal-by-feel" even in areas of the tank that I could not see because the short tube keeps the rig located on your rivet as you sqeeze the material. Worked for me. Your results may vary.

Embrace the goo!
 
Thanks to all who responded. After seeing the photo i made my decision.
Found my gasket punch, green masking tape, and a flat piece of plastic and went to work. A farm store syringe drilled out worked great for the pro seal. Many hours later a firewall to be proud of. Thanks again!


Rod
sn#120162
 
Back
Top