Favorite Wood Construction Adhesives

[Otis]

Hey guys,

I need to head to Hobbytown and pick up an assortment of adhesives for the RRR Tide project.

What types of glues should I have on the shelf? I'm needing to glue balsa bulkheads to balsa stringers, ply transom, and light ply sheeting. I intend to paint the boat when I'm done.

[vicman]

If your Hobby Town is the same as ours, I always use the two part epoxy (either 5min for speed or 30min for strength). Both will work fine on wood, where CA tends to let go after a while especially if the boat isnt sealed good. Dont let the "strength" comment fool you though, 5min epoxy will hold forever, it just dont saok into the wood as deep. Then sand it, wipe with either epoxy thinner or acetone and then your ready to paint it. I always put it in the sun for a few minutes first to heat the hull, makes the paint flow and smooth better. Pic below was done this way.

vicman/v.m.p.

[Otis]

Thanks - that's mainly what I wanted to know - CA vs. Epoxy.

[Doug Forrester]

Otis
There are many ways to glue a model together. If you are building racing boats or at the very least high performance boats then high strength and low weight are of prime consideration. Speed of building is also a big factor to me. Chemical fumes, respiratory allergies and skin sensitivities can also influence ones choices and last but by no means least, cost is a major player as well.
Personally, as a main, general-purpose glue for building all kinds of models from raceboats to airplanes, I prefer Cyanoacrylate
(Ca). Fortunately, I don't seem to suffer much in the way of serious side effects from this type of glue, although the fumes when it cures can be quite noxious and hard on the eyes. I understand that one can build up a sensitivity to the vapours but this is also true of epoxy. Used correctly, CA is very lightweight and the speed of curing allows one to build very quickly. To me, a major advantage is to be able to hold parts with fingers rather than clamps or pins for the short time it takes to set the glue. Judicious use of spray accelerator can set the CA even faster. Another plus is the ability to assemble parts and wick in the thin CA from outside the joint. This facilitates more accurate part alignment. I use both thick and thin CA versions for different applications.
Epoxy, especially the 5 minute variety, is also useful for certain jobs where high strength and resistance to vibration is necessary. Epoxy glue is not especially lightweight and it is difficult (and expensive) to use in quantities small enough not to add extra weight. Even 30 minute epoxy can be used as well when more time before curing can be useful for application or part alignment.
Spray adhesive, such as 3M Spray 77 is also handy for some jobs. There is no one perfect adhesive for all applications, just different ones with there own characteristics that suit a variety of tasks.

I hope this helps,

Cheers

[Otis]

Wow Doug - that's a lot o' info. It makes sense, though - thanks!

[Don Wollard]

Doug is the man.

I concur totally with his insiteful reply.

I build my riggers almost entirely with CA. I have seen very little joint failure when the CA was fresh. If you have prolonged exposure to humidity with an open bottle of CA, the bonding quality can sometimes change.

I ahve also notice that a bottle CA which is expose to sun light and high UV's will change color and sometimes be brittle after hardening.

Thanks for the great post Doug. I learn something new each time you comment.

[vicman]

Wasnt poking fun at different methods, have tried all I know of. It just turns out that the sime and patience I have works better with epoxy. I do use CA when I feel I need to, but is usually for something that is hard to hold on to or cant clamp. Still, "ALL" of my boats are then "skinned" with a thin layer of epoxy to seal them if they are wood. CA has its place in boats, no doubt, I just have a different way that works for (u)me(/u). We should all have all the information that is available so we can choose our own way, dont you think? Besides, I love to grovel at a nicely put together boat, I dont care if its glued with bubble gum and painted with shoe polish.

Blood flows, boats float, once the boats in the blood, you cant get it out!

vicman/v.m.p.