For all the kits I have done, you only need two types of CA, and one type of Epoxy....

Thin CA is used for gluing close-fitting parts together, and for "saturating" the balsa. Basically, thin CA "wicks" or is absorbed by wood, and does two things, if two pices of wood are touching, then they are glued together, and it also glues the wood fibres together, making the actual wood a lot stronger. Thus, Thin CA glues mechanically tight joints together, and is often used to re-inforce the actual wood such as strengthening a hole that has a screw screwed in to it. Thin CA is also used to glue "CA Hinges" in to the control surfaces (like elevators, ailerons, and rudder). Thin CA also cures almost immediately (like in 0.5 of a second). You use Thin CA by making the mechanical joint (put the pieces together), and then soaking the joint with the CA.

Medium CA does not "Wick" at all well (it wicks a very little bit). It is used to glue joints where the mechanical fit is not quite perfect. It also takes a little longer to cure, like 5 seconds. It is used by coating the one surface to join with the CA, and then applying the other surface to the coated surface, and holding together for 5 seconds while the CA cures. Medium CA can also be used to make "fillets". Where you have parts that have been joined, but still have gaps in the joint, you can run a bead of medium CA into the gap, and the CA will re-inforce the joint.

I have never used (or owned) thick CA.

Epoxy (when used right), creates a MUCH STRONGER bond than CA. It is used to join critical strength sections. (Like firewalls to the fuse, Wings to each other, and so on). Instructions normally call for two types of epoxy, 5 or 6 minute, and 30 minute. The 30 minute epoxy is "workable" for 30 minutes (i.e. you can mix it, and you have 30 minutes to use it before you have to throw it out). Really, what it means is that in 30 minutes the epoxy is tacky (sticky) enough to hold the joint together without clamps, etc. All epoxies take about 24 hours to actually cure (for them to reach full strength). 30 minute epoxy allows you to mix the parts, and then fiddle around with the fit of the joint, apply the epoxy, fiddle some more, making things align perfectly, and then clamping the parts, check things again, and leave it overnight to deal with the next day. 6 minute epoxy gives you less time to "play" with things, but it makes it easier to handle because the 6 min epoxy is tacky earlier. In reality, the 30min epoxy is (a little) stronger than 6 min, and is used for strength critical joints. You can use 30 min epoxy where the instructions call for 6 min, although it may be fiddly to hold the parts together for 30 minutes....

Thus, I use Thin CA, Medium CA, and 30 minute epoxy. I build .40 size, and I find that I use about twice as much medium CA as thin. 1oz Thin does a plane and a half. 2 oz Medium does a Plane and a bit. Thus, I buy 1oz thin, and 2oz medium for every kit I do. I have 30 min epoxy in I think 8oz bottles (epoxy comes in two parts), giving me 16oz epoxy, of which I have used about 4 oz on two planes. Thus, about 2 oz epoxy per .40 plane.

gus