There are many ways to glue coroplast. You need to get the production oils out of the glue areas for most methods although I'll admit to just GOOP-ing pieces together sometimes. Goop holds better when you prep it though.
"Flashing" involves running a flame, as from a small plumbers torch, over the coroplast to just see the "wave" of heat on the plastic. Don't aim the torch at the coro, just lay the nozzle right on the sheet so the flame is parallel with the surface. Then slide it along. KEEP MOVING! Once that's done clean the coro with Windex glass cleaner.
Another method to prep coro is to lightly clean/scrub the coro using Mineral Spirits and a scotch brite pad. Again, clean off any residue with Windex or rubbing alcohol.
For gluing, polurethane glue, such as Gorilla glue, works well if you
woodpecker the surfaces first. Before I bought the tool I just used a group of Pins stuck in some wood. The holes allow the PU glue to expand into each piece like many rivets. Folks that are allergic to CA or just want more working time only use this method.
If you use CA to glue coro to coro, put one drop every 1/4" or so in two lines. Too much glue and it will not set up. You can run a bead of glue on wood to coro joints. Here's a shot of the glue dots at the trailing edge joint on a plane I just built.
The old plans and hints are at
spad to the bone. All the new hints and designs are at
spadworld.net.
It sounds complicated but it really is easy and fast. I've been meaning to make some "how-to" vids with my new GoPro if you're interested.
OH! Hot glue does work fine but the weight adds up fast. At least it did for me. I prefer to use CA or PU glue.