Just a couple small points.
Adding an alcohol to epoxy to thin it, even in small quantities, costs a lot of strength in final cured properties. Not a good idea. If you need thinner epoxy, use a thinner epoxy. Or in some cases, brief application of heat, if the epoxy is slow cure as is the case for laminating resins.
If you find your epoxy getting thick too quickly, spread it on a plate rather than leaving it in a mixing cup. Cure time is somewhat a function of thickness of the layer of epoxy. This is particularly true of systems which exotherm a fair bit - System 3, and West with fast hardener, for instance.
I would not count on pumps providing the correct ratio of epoxy to hardener. Yes, it may still set up, but the results won't be as good as they could and should be. Weigh the epoxy and hardener.
West Systems is nice epoxy for general gluing, but one should be aware that it has one of the lower glass transition temperatures. That may be a problem for some applications with rockets. It will even soften in hot sun, depending on your location. It never really becomes fully hard (at least compared to some other systems) in that an applied load will cause yielding. When the load is removed, the part will not return fully to the original position. That is fine for a glue, as it allows some stress relief, but it may not be fine for your specific application.
My preference in general laminating resins is MGS. It has some of the best mechanical properties for room temperature cure. It is even better with hot box curing.
Most laminating resin quoted properties are for product cured according to manufacturer's recommendations - which generally includes a post-cure heat cycle. Without that, the glass transition temperature will be lower and the mechanical properties will be inferior to properly cured product. In many cases, full cure will not be achieved without a post-cure heat cycle.
I have used a fair bit of (laminating resins) System 2000, System 3, West, MGS. Of these I no longer use System 3. I use System 2000 more for mold making than anything else as I typically have a few gallons of it laying around. West, I use for gluing applications where heat is not expected. MGS I use for laminating. It has rather low viscosity and nice working properties, and some of the best mechanical properties. I use West fillers at times - worth looking into if you haven't. MGS can and particularly System 2000 should be post-cured. I don't think it will help West, unfortunately.
I use MGS for small production of fuselages for radio control sailplanes, where highest strength and stiffness to weight ratios are desired. These are thin walled parts using various combinations of high modulus carbon through low modulus carbon, Kevlar, S-Glass, and E-Glass. The low viscosity of MGS helps me to achieve proper fiber to resin ratios for good properties. The mechanical properties help in the finished parts.
I can't comment on systems I have not used enough, such as high temperature systems.
Gerald
