Multi-hull history question

So I am on to my next project- of course, another Shark... one question I have. What kind of adhesives were used in the 1960s for building beach cats. I have seen brown, yellow and white materials that seem very strong- and have held up. Used throught the boats, but I see it most where the decks were applied to the hulls.

I'm as careful as I can be when grinding these away- mask, gloves, long sleeves, and often times a shop vac. Plus, I am doing this outdoors. Even still, would love to know a bit more about these.

Thanks,
Rob

 

Depends on the specific type of construction and builder. The brown stuff is most likely resorcinol-formaldehyde, the yellow maybe epoxy, and the white either polyester or urea-formaldehyde.

 

I have only worked with epoxy in boatbuilding- are the other materials still used at all? FYI- the yellow was a creamy color yellow, so not like any epoxy I have seen.
Thanks,
Rob

 

Of course they are still used, two part epoxy is not the end all especially for open pot laminating. If it is creamy yellow, it could just be a different formulation of urea-formaldehyde, think Titebond II or III.

 

Back in the 60's and 70's I used Weldwood. It's a resin based glue. Still available. Weldwood | DAP Global https://www.dap.com/products-projects/our-brands/weldwood/ Mixed with water. When dry is waterproof. I still have some stuff I used it on 30-40 years ago. Dries to a dark brown color. Good stuff. you can get it at home depot. They make other types of glues as well.

 

If you look at part one of the Taulua movie, you can see them applying a bucket of two part urea formaldehyde glue to the plywood deck of their catamaran. I remember that these two part glues were also popular with split cane rod builders of the period.

Also in that part of the film you can see them fortifying their tar with asbestos. Good times!

Check out 15:30 for the glue.

 

Thanks for sharing this!

 

Back in the 80s when making strip canoes and bent shaft paddles I used a lot of Weldwood. It was a tan powder one mixed with water. Nice to work with, required actual clamping, so in that regard it was not as forgiving as epoxies can be. It is apparently a UF glue. I got a fantastic case of dermatitis, which I attributed to the glue, so I stopped using it. Looking back, I occasionally used gloves over barrier cream, and that can cause dermatitis. Though with Weldwood, being "water based" I probably wasn't wearing gloves.

I don't think one can glue to Weldwood with Weldwood. Not sure. I always used it in a woodworking way, where by the time secondary bonding entered the picture, the piece had been reduced to essentially an all wood surface.