Sunday, October 08, 2006

Woode boat Construction -- glues and adhesives

John F. Howard (Star-45 discussion forum, July 31, 2006)

"Gorilla Glue does foam a bit, but nothing like foam-in-a-can and has minimum stink. Forget trying to smooth things out, the foam is very, very sticky and keeps growing until it sets up (about an hour) at which point it will still be a little soft (keep clamped for 3-4 hours). Any squeeze/foam out once hard, can be cut, chiseled or sanded smooth. Run a strip of tape along the edge of the glue line and most of the foam out will end up on the tape. The best joints are tight ones that use a minimum of glue. For narrow or thin pieces (planking), squeeze out a little puddle (just enough to use in 15-20 minutes) and use a Popsicle stick to spread along the edges. Wear gloves, the stuff stains and is sticky. GG is great for laminating larger areas (spread with an old credit card or playing card)."

"If you use epoxy resin such as West Systems (best, you can adjust the cure rate with the different hardeners) or one of the 30-minute or longer (5-15 minute never gets hard and remains rubbery) such as sold by Great Planes or Tower, stink will not be a problem. The polyester resin does STINK in a big way, it what you can smell in a new fiberglass hull.
CA glues are ok for "tacking" stuff in place until the epoxy sets up, but watch the fumes. CA will fail if used in a wet location for long and also cause a problem with the wood accepting stain. Work with plenty of ventilation and or respirator and wear gloves with any of the above glues and resins, staining of the skin and sensitivity, either skin and or breathing can occur."

"These are base on my experience with the glues mentioned (full size boats, cabinet work and models). Yellow glue such as Titebond or Elmers Carpenter Wood Glue (not waterproof) works fine when encapsulated with epoxy (cedar strip canoe builders use it all the time)."

{ http://groups.yahoo.com/group/Star45/ }

Phil Geren adds a warning note about Glue Fumes:
I have a serious allergic reaction to CA fumes - causes fluid to build up in the lungs, like pneumonia. I still use it, but with a fan blowing air between me and the work. Trying to avoid it.

Phil Geren on Gorilla Glue:2006 August 1
Is it rock hard or rubbery when dry?
I bought some, but have the same reservations as Dave M about foaming, trimming, and sanding. If it doesn't sand well, the finished product won't be as good as what I am aiming for.