Don41

I had this bright idea (I hope it was) to use Titebond III as fuel proofing in the engine compartment of my Elder40. Now I'm having second thoughts.

Do you fellows think it's fuel proof?

Anyone ever test it?

tstotts

I brush on a thinned down solution of 30 minute epoxy. I know it's fuel proof.

Gray Beard

My Feedback: (-1)

I too use the thinned down epoxy, I know it works.

vicman

My Feedback: (10)

I wouldn't do it.
It won't seal the wood and may not even fully cure properly. There are many great opportunities for Titebond, this aint one of them. Hold a firewall in yep, but go back with thinned epoxy like is mentioned above. I would also recoment using 20 min and denatured alcohol. It works perfect.

jmv

An excellent discussion of various glues, their uses and their properties can be found here:

http://www.airfieldmodels.com/inform.../adhesives.htm

Don41

Thanks guys. I wanted to get the job done today (I live far from town and I don't have the thinning agent on hand) so I'll coat the glue with some clear dope.

Unless of course that's still another bad idea (:-)

Regards

Don41

Thanks JMV. The following snip pretty much says it all (:-(. One thing though,,, I disagree with him on edge gluing. I find Titebond III to be excellent when it comes to not leaving the dreaded bump.


SNIP
Aliphatic Resin
Also called Carpenters Glue

Aliphatic resins are inexpensive, light and strong. Carpenter's glue is the primary adhesive I use to build flying model aircraft. It's longer working time allows me to ensure everything is as it should be before the glue sets up.

Because it is water-based, aliphatic resin also allows neat glue joints because excess glue removes easily with a damp sponge or paper towel while the glue is still wet.

In addition to common aliphatic resins, there are also so-called "sandable" resins. I do not use them because the additive to make them sandable probably weakens the glue. I do not know this for a fact, but it makes sense to me. Carpenter's glue sands easily enough that it is not an issue in most cases.

*

Fuel proof

No. They are fuel resistant to a point, but extended exposure to raw fuel or exhaust residue will break them down.
*

Clean-up

Water while wet. Acetone when dry.
*

Examples
o Titebond
o

Elmer's Carpenter glue
o

Pica Gluit
*

Use for
o

General construction.
*

Do not use for
o

Non-porous surfaces.
o

High-stress areas (firewalls, landing gears, etc.).
o

Edge joining sheets of balsa — it does not sand as easily as soft balsa and will leave a nasty ridge when you try to sand the sheet flat.
o

Laminating broad areas — it will cause severe warping. These glues are water-based and dry by evaporation. If you place the part under a lot of weight until it has dried thoroughly then it might work for laminating, but I wouldn't do it.

However, it can take several days for it to dry — even longer if you have put plastic on both sides to prevent the part from sticking to the bench or whatever weight is used. Generally it is a better idea to use a different type of adhesive for laminating parts.

Kaos Rulz

Don41,

If all you want to do is fuel proof the wood, use the clear dope and forget about the glue. The glue is not fuel proof, but the dope is. Just use the dope.

jmv

Don41,

I agree with you about sanding Aliphatic glues. I find that they sand very well (I've used Sig Bond). I'm a new builder, but I love to work with Sig Bond. No fumes and burning eyes. You can wipe off undried glue with a wet cloth, so there is less mess to sand away in the first place. I know it may sound counter-intuitive, but I found that the fact it dries slow was a major advantage in building my first kit. Sure, I had to clamp/pin/weight down things, but there were a few times where I made a mistake that would have been a real pain to fix if I had been building with CA. For example, altough Great Planes did everything but have a big hand come out of the instruction booklet and slap me across the face, I actually DID manage to make two left fuse sides. However, since I was building with Sig Bond and I noticed after a few minutes, I simply pulled the pieces apart, wiped them down with a wet cloth, and then set them up right. I don't like to think where I would have been had I just hit the joints with thin CA. Anyway, I'm hooked on building with Sig Bond and Epoxy (where needed). I am curious about Sig Bond vs. Titebond II vs SuperPhalic. Guess I'll have to try them all and see for myself.

vicman

My Feedback: (10)

You would be like me and many others with an extra fuse side sitting in the balsa box.

jmv

Now that's funny!

Charlie P.

If you want to sand it afterwards use good old fuel proof dope.

Getting kids high since 1930.

Flypaper 2

Make sure it's butyrate dope. It's fuel proof . Nitrate ain't.