Ok, so when a kit says to "Thin CA" this or that, I would use thin CA, when it says to use the wood resin stuff, i use that and so on. But when all it says is, "glue this chunk of wood to that chunck of wood" and doesnt say what kind of glue, what is best? I have just discovered Titebond wood glue and am finding that when I get a little too excited and get glue everywhere, it is 1) easier to get out of my hair, and 2) easier to sand off. The bottle says that it "bonds wood best...." but then so does the bottle of CA. So, what are all ya'll's thoughts on the matter?

-Jim

When glueing two pieces of wood together, I use thin CyA. I built my Somethin Extra that way, and it came out lighter and stronger than any other at the field. The only place that had epoxy on it was the metal elevator joiner because I ran out of CyA... The thin CyA soaks into the wood making your joint stronger than the wood around it. I saw a guy use carpenters wood glue on an airplane, and it added about a pound of weight. Although it was pretty strong, it was so heavy it was almost impossible to fly. I'm not saying that carpenters glue is bad for everything, but I would try to stay away from it most of the time.

I agree that the alphatic resins are much superior to the CA's for most applications, stonger, more shock resistant, do not cause alergic reactions, much less expensive and more foregiving for most uses. Properly done, the wood will always break before the glue joint does.

You can use the yellow wood glue just about anywhere to replace CA (except for the CA hinges)... you can't get away with replaceing the yellow glue with CA in as many cases.

Yellow glue is far superior to CA for joining lite ply, especialy edge to face. (as in putting in a bulkhead.) You have to put in 3 times the DRIED weight in CA to get the same strength as with yellow glue.

For a neat trick in lightening a plane a bit... replace the fiberglass/epoxy dihedral joint tape with silk and yellow glue. Smoother, lighter, covering bonds better... (And she may never miss that old scarf... ) 2 layers common scarf weight (10 mm Habotai), the first 1 inch wide, second 2 to 3 inches wide, replaces a 2 inch wide 2 oz fiberglass tape.

So.. when in doubt... use Yellow glue or Epoxy.
(How'd epoxy get in here?)

Epoxy is just about the ONLY glue for putting in a firewall or mounting landing gear blocks. (yellow glue sometimes is OK for landing gear blocks) Epoxy is also the best for most dihedral joints.

I'm really a fan of the polyurethane adhesives now available, like "Pro-Bond" and "Gorilla Glue". They work on balsa, ply, plastics, even aluminum. Firewalls, landing gear blocks, and wing-mounting blocks are fine. I think the stuff is better than epoxy. They are not toxic.(but don't get them on your hands anyway...your fingertips will be black for several days before it wears off). They expand as they harden, so they fill gaps. They are sandable...probably better than aliphatics. Fuelproof, waterproof. The only down side is you have to glue stuff, clamp it in place, then leave it for a coupla' hours.

I built my last four planes using almost nothing but PU glues, and they are light, strong, and not brittle. I built a Wonder with it, and dumb-thumbed it into the ground at full-throttle. It broke a lot of wood, but not the glue joints. My Senior Telemaster has been flying (on floats) for over a year without a problem.

Thanks for all your imputs! I think I am becoming a new fan of titebond... I just wanted to make sure that it was ok to be using it rather than CA thanks again

-jim

I've gotten bit by firewall joint failure from fuel seepage every time I've tried yellow glue on the firewall.

I know... probably bette fuel proof coating would prevent that... but. Its sooo easy to have fuel seepage, and not know it. And the epoxy helps prevent it going through a cracked firewall joint. (because the joint won't have cracked from fuel seepage. A case where circular logic really does work.)

FHH:
You're talking about aliphatic resins. Titebond, Elmer's Carpenter's glue, etc. Those go on yellow and they dry ...yellow. Still, they have the rubbery consistency of a vinyl handlebar grip. In my experience they are sandable but not really...they ball up and clog the paper.

Polyurethane glues go on clear amber and when they harden they foam up a bit and become light yellow. They become a bit more rigid than aliphatics, so when they are sanded, they don't clog the sandpaper.

My experience:

Use thin/fast CA for all balsa to balsa joints.
Use medium viscosity CA for all lite ply to ply/balsa joints.
Use good old soda and fast CA for gaps in wood joints.
Use 30 min epoxy for fire wall and landing gear mounting sheet.

This not only saves weight but the job is done in a jiffy, after all who can wait for the water based glues to cure.

You can get Titebond II at most any hardware or discount store in the USA. Yes, all the alphatic resins are pretty much the same, the only reason I use Titebond II more than the others is that it seems to be much more water resistant. In fact, I've soaked joints made with Titebond II for 24 hours (after a full days curing time first) and the joints held up well. I have not tried that with the others so don't know if they would do as well or not. There are some alphatic resins that sand much easier than Titebond but that is not usually a problem for me. I usually by it in the quart size and have several smaller bottles (and one syringe) that I fill and use to apply the glue. You can get syringes for glue from some of the woodworking catalogs, they come in very handy for getting into the tight spots.

>>GLUES<<

Even after 12 responses to the CA vs. Wood Glue question, there is one advantage the aliphatics have that no one has mentioned yet:

If there is a wood joint that you may need to undo later on, such as for mods or repairs, an aliphatic joint can be separated using a single-edge razor blade! Place the blade in line with the glue joint, and press firmly on the nice, rounded edge and feel the joint being separated SMOOTHLY, with no herky-jerky jumps, cracking or splitting! This would never work with CA!

Johnny