Canvas and tar boatbuilding

Using asphalt roofing tar (like Henry 208) can be a cost-effective alternative to expensive bedding compounds like Life Caulk. It should work for sealing the canvas, as it's designed to perform in wet environments. However, keep in mind that asphalt tar might not have the same longevity or flexibility as marine-grade sealants, and could crack over time due to constant water exposure and boat movement. Test it on a small area first to see how it holds up. If it works well and you’re okay with occasional maintenance, it could be a good budget-friendly solution for your build.

 

I finished the boat! I ended up using butyl rubber to seal my canvas and putting the canvas in between the double plank. In comparison to single plank, It was alot more work and heartaches, between the planks splitting so easily and swelling so easily. (I made a big mistake a while back building it outside and didn't tarp it up one evening. The bottom turned into a mountain range! Once the planks were unswollen, I made quick moves to fasten them to the runner going down the middle, which will prevent the individual layers of planking from going mountain again once they're in the water). Thanks everybody for all the help and advice you guys offered!

 

What is the weight of the finished boat?

 

130 lbs

 

For thick planks you can bolt mahogany dovetails profiles and assemble all planks that way. It's glueless and chemical-less and i don't know why boatbuilders haven't included dovetails in hull construction, both for joining strips to frame and between strips

Also fabrics can be waterproofed with wax (nontoxic soy wax will do) or vegetable oil (coconut oil doesn't get much rancid) and you con use that fabric in tension to reinforce the hull using rather hemp fabric in curved hulls

With veneer cold forming and tensioned waterproofed hemp fabric sandwich construction you can apply several layers that deliver both compression from wood and tension from fabric, and this can move epoxy and all these toxic nanoplastic chemicals from boatbuilding

 

I think you may be smoking the boatbuilding supplies.