I am working on my third stripper. I have built a Great Auk kayak and a Wee Lassie II. I am now starting a Freedom 17. I reading the build notes, I did not see any mention of using a second layer of fiberglass over the stems. I was under the impression that this bias-cut reinformcement was necessary.
How do you do your fiberglass lay-up? Single 6-oz layer in and out> Additional layer of 6-oz on the football? Reinforcing strip along the stems? Opinions are solicited.
Fiberglassing the stem
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Charles G. Clark, Jr.
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Glen Smith
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"Traditional" canoe stems have a brass stem band on them for protection and the outer stems don't have glass wrapped around the end. If you don't plan on using brass stem bands you should apply a few layers of bias-cut cloth over the outer stems for added protection.
As for extra layers of glass on the hull, if you think you need it you could add an extra layer over the football area both outside and inside. Extra glass outside increases the abrasion resistance and extra glass inside increases the puncture resistance.
My personal boats only see light usage and I just use one layer of 4 ounce glass inside and out. For heavier usage I would apply 6 ounce glass and if I was planning on using a boat in places where I would have to drag it over beaver dams, across rocks or fallen trees I would add a second layer on the football inside and outside.
As for extra layers of glass on the hull, if you think you need it you could add an extra layer over the football area both outside and inside. Extra glass outside increases the abrasion resistance and extra glass inside increases the puncture resistance.
My personal boats only see light usage and I just use one layer of 4 ounce glass inside and out. For heavier usage I would apply 6 ounce glass and if I was planning on using a boat in places where I would have to drag it over beaver dams, across rocks or fallen trees I would add a second layer on the football inside and outside.
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Erik, Belgium
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I can't add anything to your building method: Single 6-oz layer in and out, an additional layer of 6-oz on the football, and reinforcing bias strips along the stems. Build it like you intend to, and it will turn out perfect.
I can't comment on the 'traditional' brass band, since I don 't like it. (and never used it)
Erik, Belgium.
I can't comment on the 'traditional' brass band, since I don 't like it. (and never used it)
Erik, Belgium.
In addition to the above, instead of a brass stem band, strips of thicker fiberglass matting were epoxied in where the stem band would normally be. Ordinary fiberglass cloth creates a very thin layer and doesn't offer much protection in high-abrasion areas. To fair the strips into the hull, I used chopped glass fibers mixed into epoxy to build up fillets and a skid plate area underneath the stems where abrasion tends to occur the most.
The thicker areas of glass and epoxy turned out to be an amber color, not transparent, but still allowed the color of the wood to come through. My plan was to use several coats of tough marine paint to add another abrasion layer over the entire exterior of the hull, to act like gelcoat and help prevent ongoing wear from getting at the fiberglass and wood. The paint color complements the interior wood tones very well, and IMO enhances the overall look.
All these measures added on several more pounds of weight... LightJay would never have included these, but then he damaged his hull in some rapids in Temagami... that would have meant another shaky duct tape repair job with more work needed in the shop.
The great thing about strippers is that you can build whatever you want... I like 'em durable, others will prefer lighter. Being cedarstrips, they all look better and have more individual character than those that are factory-built.
The thicker areas of glass and epoxy turned out to be an amber color, not transparent, but still allowed the color of the wood to come through. My plan was to use several coats of tough marine paint to add another abrasion layer over the entire exterior of the hull, to act like gelcoat and help prevent ongoing wear from getting at the fiberglass and wood. The paint color complements the interior wood tones very well, and IMO enhances the overall look.
All these measures added on several more pounds of weight... LightJay would never have included these, but then he damaged his hull in some rapids in Temagami... that would have meant another shaky duct tape repair job with more work needed in the shop.
The great thing about strippers is that you can build whatever you want... I like 'em durable, others will prefer lighter. Being cedarstrips, they all look better and have more individual character than those that are factory-built.
I also prefer glass to brass on the stems. With 6 oz cloth inside and out, and three layers of bias cut glass reinforcement on the inside and outside of each stem, I'm confident of my last canoe's strength. It does not add much weight: the total for the 18' wilderness lake canoe is under 50 lbs.
The bias strips are added after glassing the hull, but before the fill coat(s). Each of the three layers is an inch or two narrower than the one applied underneath it. (Something like 6", 4", and 2" wide.) All three are wetted with epoxy, and applied one immediately after the other with careful stretching to avoid any wrinkles. To avoid sanding to feather in the edges of the strips, a sheet of polyethylene is used to cover the wet epoxy, and a brayer (hard rubber roller) is used to roll the edges down thin and smooth. After the epoxy sets, peeling off the polyethylene leaves a smooth surface that needs very little sanding to remove steps at the glass edges, and even little filling of the weave where the plastic pressed. (Do not use saran food wrap for this film. It sticks and shreds as you try to remove it.)
The reason to apply the narrower strips on top of the wider ones is so you don't cut through and weaken the wider ones as you sand smooth the edges. It's plausible that using the plastic film and brayer method, that would not be a concern.
The bias strips are added after glassing the hull, but before the fill coat(s). Each of the three layers is an inch or two narrower than the one applied underneath it. (Something like 6", 4", and 2" wide.) All three are wetted with epoxy, and applied one immediately after the other with careful stretching to avoid any wrinkles. To avoid sanding to feather in the edges of the strips, a sheet of polyethylene is used to cover the wet epoxy, and a brayer (hard rubber roller) is used to roll the edges down thin and smooth. After the epoxy sets, peeling off the polyethylene leaves a smooth surface that needs very little sanding to remove steps at the glass edges, and even little filling of the weave where the plastic pressed. (Do not use saran food wrap for this film. It sticks and shreds as you try to remove it.)
The reason to apply the narrower strips on top of the wider ones is so you don't cut through and weaken the wider ones as you sand smooth the edges. It's plausible that using the plastic film and brayer method, that would not be a concern.
Alan
Ed:
I think the polyethylene was 4 mil, but I am not sure, and don't think it would matter much for the places I used it: the stems, and once on a small patch. If you were to try this on a large area of a hull, you might want to stretch it to match the compound curve. I have not tried to do that, but the weight would probably matter, and heat would probably help to stretch it. I'd probably try covering it with a towel and using a clothes iron. Only after making it fit would I begin to mix the epoxy.
By the way, I made sure to avoid creases in the plastic, as a test run had shown me it's difficult to smooth those out enough simply by rolling. I expect that ironing first would remove creases.
Alan
I think the polyethylene was 4 mil, but I am not sure, and don't think it would matter much for the places I used it: the stems, and once on a small patch. If you were to try this on a large area of a hull, you might want to stretch it to match the compound curve. I have not tried to do that, but the weight would probably matter, and heat would probably help to stretch it. I'd probably try covering it with a towel and using a clothes iron. Only after making it fit would I begin to mix the epoxy.
By the way, I made sure to avoid creases in the plastic, as a test run had shown me it's difficult to smooth those out enough simply by rolling. I expect that ironing first would remove creases.
Alan
Alan