I can add a couple off observations to the innie-outtie debate, lol. I have always put a football on the outside (football first, under the full sheet). However, the only major destructive events that have happened with my canoes have been inside hull separations, which lends credibility to the inside football idea.
There is another however, however.
I had an 18 foot J. Winters Quetico that I had built early in my canoe building experience, and I only used a single layer on the outside hull. It held up fine, however, on one port clearing trip down the Steel river, a particularly difficult log jam made for some interesting acrobatics at the end of the port. There was about a six foot cliff that one had to negotiate, and once the canoe was in the water, I simply jumped off the cliff into it. Unknown to me, there was a large tree underwater, and when I landed, the glass on the inside hull split for almost 2 feet in a line running up the centre of the canoe. We were still several ports and around 40 miles from an extraction point, and it was a very hairy trip, with the big split winking at me with every paddle stroke. I was sure the exterior glass was going to separate at some point and we would end up Titanic-ing.
I know that if I had a second layer of fibreglass inside the canoe, the catastrophic failure would most likely not occurred. However, I also believe that of I had a football on the outside, it mightn't have occurred. Or, even if the results were still the same, I would have at least had 12 ounces of glass holding the winking gap together for the final push.
The other similar event happened in my first Raven. On that one, I used 4 once cloth for the football, covered with 6 ounce for the whole sheet. I had a single layer of six inside. I was on a trip with the school, paddling at full speed, when I ran up hard on the point of a rock. The contact was right under my feet, impact was severe. Again, the glass inside the canoe fractured, but only for about 3 inches. I was able to conduct a repair in the field, as I usually took a small resin/glass repair kit.
If weight were not an issue, I would say do the inside and outside. On my 20 foot freighter, due to the size and use of a motor and the unimportance of weight, I did multiple layers of 10 and 6 ounce cloth, inside and out.
For some unknown reason, despite evidence to the contrary, I still continue to put the football on the outside, perhaps because I treat my canoes so rough, lots of dragging, etc.
I did stretch that Quetico out to a 20 foot canoe, and on that one I used a single sheet of 10 ounce cloth on the outside and the inside. That was a bomb proof layup, and after 20 years of hard use, that canoe is still going strong. On the Quetico the students are currently building, we will be using the standard exterior football (under the glass). The Under-over football is a discussion where I think everyone should just do what they like best. I haven't experienced any adverse effects from doing it my way, and our canoes probably get beat up a lot more than the average stripper, so I'm going to speculate that the under/over debate is more a matter of personal preference than one of structural integrity.
There is another however, however.
I had an 18 foot J. Winters Quetico that I had built early in my canoe building experience, and I only used a single layer on the outside hull. It held up fine, however, on one port clearing trip down the Steel river, a particularly difficult log jam made for some interesting acrobatics at the end of the port. There was about a six foot cliff that one had to negotiate, and once the canoe was in the water, I simply jumped off the cliff into it. Unknown to me, there was a large tree underwater, and when I landed, the glass on the inside hull split for almost 2 feet in a line running up the centre of the canoe. We were still several ports and around 40 miles from an extraction point, and it was a very hairy trip, with the big split winking at me with every paddle stroke. I was sure the exterior glass was going to separate at some point and we would end up Titanic-ing.
I know that if I had a second layer of fibreglass inside the canoe, the catastrophic failure would most likely not occurred. However, I also believe that of I had a football on the outside, it mightn't have occurred. Or, even if the results were still the same, I would have at least had 12 ounces of glass holding the winking gap together for the final push.
The other similar event happened in my first Raven. On that one, I used 4 once cloth for the football, covered with 6 ounce for the whole sheet. I had a single layer of six inside. I was on a trip with the school, paddling at full speed, when I ran up hard on the point of a rock. The contact was right under my feet, impact was severe. Again, the glass inside the canoe fractured, but only for about 3 inches. I was able to conduct a repair in the field, as I usually took a small resin/glass repair kit.
If weight were not an issue, I would say do the inside and outside. On my 20 foot freighter, due to the size and use of a motor and the unimportance of weight, I did multiple layers of 10 and 6 ounce cloth, inside and out.
For some unknown reason, despite evidence to the contrary, I still continue to put the football on the outside, perhaps because I treat my canoes so rough, lots of dragging, etc.
I did stretch that Quetico out to a 20 foot canoe, and on that one I used a single sheet of 10 ounce cloth on the outside and the inside. That was a bomb proof layup, and after 20 years of hard use, that canoe is still going strong. On the Quetico the students are currently building, we will be using the standard exterior football (under the glass). The Under-over football is a discussion where I think everyone should just do what they like best. I haven't experienced any adverse effects from doing it my way, and our canoes probably get beat up a lot more than the average stripper, so I'm going to speculate that the under/over debate is more a matter of personal preference than one of structural integrity.
