I have a used 15 foot fiberglass canoe .How do I stiffen the floor to keep it from flexing.The flexing seems a little excessive.
If you’re referring to what is called
"oilcanning", you can try adding some kind of struts between the thwarts and the floor. Some people have made them from chunks of minicell foam to minimize added weight.
If the canoe shows excessive wear or damage, you may need to make structural repairs to the hull.
It might help to know the make/model of your boat for better advice.
Excessive compared to what?
Perhaps it’s completely normal for whatever unidentified canoe you have.
its a 15 feet 8 inch River bend canoe
Googling River Bend Canoe comes up with a long list of campgrounds with canoe liveries. One suspects your canoe was manufactured for private label by some other builder.
To stiffen it you’ll need a keelson and a couple pogo sticks. The keelson is a longitudinal piece of wood cut, then sanded to lay down the keel-lone inside the hull. several coats of oil of PU are then in order. The next step is to devise telescoping, spring loaded braces from the keelson to each thwart, noting that several canoes lack a third thwart and you may need to make one.
A cooler, well stocked
After that things get complicated and are probably not worth the expense and effort.
Thank you very much
center rib reinforcement
Charlies idea is your best way to go. For the thwart to keelson (center-rib) shock absorbers you can go to a Wenonah dealer. What Charlie has described is what Wenonah offered as a Center-Rib layup. they used a foam rib laminated into the bottom of the hull that ran the length of hull. There were several spring loaded shock absorbers mounted from the rib upward to the thwarts. The shocks are very similar to the spring loaded tailgate/hatchback lifts on cars.
A junk yard and a lumberyard are all you might need to simulate the center-rib layup. I’d use a wood with a bit of flex to it. You still want it to give if you run over something in the water. And shocks that are near the end of their extension when you mount them so there is a lot of compression available when you hit something.
Centre Thwart Brace
My Oneida 18’s bottom bulges inward when the canoe is empty. The fix - a simple brace, made of a 1"x2" notched to slip beneath the centre thwart, and a 'shoe" plate of 12"x4"x1/4" cedar beneath it to distribute the load. Costs nothing, works like a charm. If there’s camping gear aboard, jamming a knapsack under the thwart accomplishes the same result.
Wise words to live by
Any chance I can find some images of what this looks like anywhere.
center rib stiffening
old Wenonah catalogs showing center rib layups. it was available on the WW solo canoes, the composite tandems for tripping and downriver. Have lots of them at home but no way to transmit images to you. Any established Wenonah dealer should be able to help you.