Float bag installation in Kevlar boat

Glenn MacGrady

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The reason that lacing is required is to hold the bags down within the hull. Otherwise any water that enters the boat goes underneath the bags and floats them up above the gunwales. If the bags are secured only at the corners the center of the bag will pooch way up.

I'll just have to disagree with this if we're talking about a big center bag (or tire tube in the old days) jammed under the center thwart. Water can't float such a bag up, if it's fully inflated, because of the thwart, and there will be very little stress on the corner grommets. All my whitewater canoes -- only one of which is Kevlar, the others being plastic -- have end bags in cages, which I never remove. The string cages and bags stay in the boats permanently until the bags fail.

My reluctance about cages in this post is because I am assuming the boat in question will not be a dedicated or hard core whitewater boat, but mainly a flat water boat. If it is mainly a whitewater canoe being used in class 2+ maximum, I'd end bag it with cages using one of the attachment mechanisms described above for vinyl or aluminum gunwales. I don't think an additional huge center bag is necessary for such mild whitewater unless the paddlers are quite novice, in which case I'd use the center thwart jam for it.

For the wood gunwales on my Kevlar WW canoe 40 years ago, I used low-tech screw eyes into the wood for the end bag cages.
 
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Thinking about it, and looking on the racks, nearly all of our canoes have attachment points for float bags, which double as tie points for packs or barrels on trips. I don’t paddle much whitewater, nor usually tie in gear other than a webbing strap across the don’t-want-to-go-hungry food barrel, but when I do I want easily accessible attachment points.

Only one canoe, the Mohawk Odyssey, has bags and lacing left in place full time. The reason for that is in part because it’s easier to have one canoe with float bags ready to go at a moment’s notice, and in larger part because that canoe came used with (factory) drilled through hull lacing and bags, and is/would be a PITA to unlace and re-lace if I wanted no bag & no lacing. All of the other canoes have easier attachment points.

Cathy, one more hint if you are lacing and unlacing float bag cord. If, like me, you have an assortment of cord and line and rope it helps to put the removed float bag lacing in a Zip-lock and Sharpie the bag “Prospector center bag” or “End bags”, etc.

Cutting new cord sized to the perfect lacing length when you know you already have a piece you removed, stored somewhere, sounds like something I would do. Done did. That becomes even more confusing if you have multiple canoes and different sized float bags & lacing that you remove and reinstall as needed.

Make that two hints. If you have not used float bags before be aware of over inflation with bags in the canoe; on the water, on the storage racks or on the car.

On hot days the bags will swell, enough that the bags will be bulging against the lacing or pulling hard at the D-rings. I’ve read one tale of a guy who left float bags in his canoe on his car for a couple hot sunny summer days; the over-inflation ripped the D-ring pads off the bottom of the canoe and, Royalex canoe, took some vinyl skin with them. It was at least proof of proper adhesive.

With bag installed I often let a little air out when/before the bag begins to swell alarmingly, sometimes partway through a hot summer day on the water. With the Mohawk Odyssey I let a little air out before I put it back on the outside rack, just to be on the safe side.

Eh, threefour hints. When outfitting canoes I check to make sure that there is nothing sharp or pointy in the hull that might puncture a bag, especially when it becomes over inflated, or is left in place on long highway drives where the 70mph windage might flap it around. Likewise for the force of the water pooching bags inverted upwards in a capsize.

Towards that no-sharps the shank ends of machine screws all get thread protectors or cap nuts (under the webbing loops, hint hint)

I am somewhat leery of making long highway drives with float bags already in the hull. That may be overly cautious; I’ve done 9 hour interstate drives with bags left in the Odyssey. I do check them at gas stops, found them mid-day well-swelled bulbous, and let a bit of air out. I often start long drives well before dawn; by afternoon the temperature and sun exposure may have changed considerably.

In lengthy travel with our other canoes I’ll install the lacing at home and use a high volume low pressure 12V air pump off the truck in inflate the bags at my destination, tucking them in place under the lacing and attaching the end lines to the D-rings.

Quality floatation bags are not cheap (or available like beef jerky at backwoods country stores) and arriving somewhere distant to discover the bag was damaged/holed/deflated in transport would be disconcertingly problematic.
 
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I have popped anchors off the hull floor used to secure "keeper" straps over the bags when they got too tight on hot days. Although it has not happened to me, I know a couple of people who actually broke gunwales on boats as a result of over-inflated bags. Conversely, when you put on a cold water river on a warm day your bags may quickly lose up to about 20% of their volume and need to be topped up.

I have damaged a number of bags or the filler tubes on bags when I got too lazy to take them out before a lengthy drive. I heard a tip from Paul Mason once who cuts pieces of Coroplast to the size and shape of the ends of the boat and slides these under the bag cage lacing and over the bags to protect the bags from wind when driving and eliminate the need to remove them.

I do exactly the same thing as Mike when I remove cordage from a particular canoe, put it in a zip lock bag with a label indicating which canoe it goes in.
 
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I have popped anchors off the hull floor used to secure "keeper" straps over the bags when they got too tight on hot days.

I’ve seen a bunch of anchor pad failures, most though I believe due to improper installation technique or adhesive choice, so not likely Pblanc’s work.

I don’t think contact cement, even a proper couple coats on both surfaces, dried to barely tacky and hit with a heat gun, is an adhesive of choice in vinyl pad installation.

I have an unopened tube of generic “Vinyl Adhesive” for pad installation on Royalex, but since Vynabond disappeared from the market have just used G/flex epoxy on both RX and composite hulls. No issues 10 years on with G/flex.

One coat the bottom of the pad and lay and press in a predetermined trace outline in the hull (make sure the D facing orientation is correct). I use a little hard surface roller to push down the pad, cover it with a sheet of wax paper and pile a couple Zip-lock bags of sand on top. And take the sand bag weights off every 30 minutes or so and re-roll in case any area lifted. And repeat that remove/roll/replace for a couple hours. Finger pressed would do (almost) as good as hard rollered, but a cheap wallpaper roller is all of $4, and is handy for a lot of compression applications.

https://www.acehardware.com/departme...E&gclsrc=aw.ds

(NOTE: I have not replicated the weight bearing experiment using vinyl adhesive, G/flex, standard epoxy, contact cement, MondoBond, etc to adhere vinyl D-ring pads. Even single D pads run $6 each, and I’d want stainless D’s, nylon D’s, maybe webbing loop “D’s. I would still love to know what failed first; adhesive, pad or ring, at what suspended weight, but I’d need at least a half dozen vinyl pad D-rings, and I’m not (yet) $40 curious)

https://topkayaker.com/index.php?mai...roducts_id=544

Beyond complete vinyl pad failures I’ve seen many pads where the edges had begun to lift. Water, dirt, sand and grit infiltrating under the lifted pad edge doesn’t bode well. Perhaps also improper adhesive or application, but that pad lift is an eventual death sentence.

I’m convinced that running a bead of transparent Goop Sealant (Marine Goop, Plumber’s Goop, or E-6000 adhesive sealant, which seems just as good and half the price) is helpful to prevent any water/grit/etc from creeping under the slightly raised edge of the pad.

Only takes a few seconds to run a bead of transparent E-6000 around the perimeter of a vinyl pad after the epoxy has cured, and a $4, 3oz tube would do dozens of pads. I run a bead of E-6000 around the perimeter of any contact cemented minicel for the same reasons; easy to do, inexpensive, and it works.

https://www.walmart.com/ip/Eclectic-...arent/44148643

Looking at the photos of the center bag in the Wenonah Prospector I would definitely want end bags for paddling WW solo. Maybe with the already-owned center bag in place as well. If solo paddling the Prospector is done bow backwards the bag would need to be moved to the other side of the yoke for leg room, so a stripe of painter’s tape marking on that end as well, and more lacing holes/tie downs at that end as well.

A minimalist center bag lacing approach might be:

Vinyl D-ring pads to anchor the four corners of the bag. You might get away with using a single D-ring pads, keel line centered at each end of the float bag, running the cord ties from the corners of the bag to the D-ring \ /. That actually starts a bit of a rudimentary end cage, so the bag can’t shift fore or aft in a capsize and overly strain any attachment point.

Webbing loops on machine screw ends on the yoke, and on the machine screws that hold the seats to the aluminum plate drops, would at least provide an X of cord across the top of the bag.


Plus a webbing strap across the top of the float bag, from the center of the yoke to the seat frame. I don’t often completely tie in my gear (and it’s usually trapped under a spray cover in any case), but I do like the ease of running a single pre-sized length of webbing strap over my main dry bag and food barrel, so that strap sees a lot of use, float bags or not.

That solution, while minimalist, would require drilling a lot fewer holes. Or you could just go really old school, inflate a truck tire inner-tube below the yoke, and hope for the best.

About using rope loops as tie downs; I don’t mean to disrespect paired rope loops or cord as tie down points, an honored old-school solution. I have in-out, in-out lacing under the gunwales on several canoes, some for floatation, some for spray cover attachments (or both). Not run as float bag lacing criss-crossing the gunwales, just in-out, in-out cord run every 6 or 7 inches below the gunwales on both sides.

That in-out under gunwale cord length is spacing-marked and drilling holes every 6-7 inches easy to do, and the cord can stay in place; it doesn’t look as fugly as cross lacing with no float bag underneath (just lace through in-out cord on the inside of the canoe when you want cross-gunwale cordage). It works for flotation or gear, and a length of cord, run in-out, in-out every 6 or 7 under the wales provides a lot of tie points, both inside and outside the hull.

I heard a tip from Paul Mason once who cuts pieces of Coroplast to the size and shape of the ends of the boat and slides these under the bag cage lacing and over the bags to protect the bags from wind when driving and eliminate the need to remove them.

I like that idea. Coroplast is the stiff, lightweight corrugated plastic used in better quality yard signs during election season. Waterproof and weatherproof, and cuts like butter with a band saw. Damn, I want a couple wedge shaped pieces to tuck between the lacing and bags on the Mohawk

I waited a day too long last election cycle.

https://www.canoetripping.net/forums...ction-reminder

I now know that I need to be at the polling place when it closes. Campaign workers remove the signs that same night, and those signs go in the landfill. Coroplast is quite a durable plastic, so archeologists can try to decipher the meaning of “. . . AKE . . . RICA. . . ATE. . . GAIN” in a thousand years.

Jeepers creepers, I’ve run over my allotted bandwidth once again. I do enjoy canoe outfitting discussions, and I’m still learning new and improved tricks.
 
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I have found contact cement of any type to be totally inadequate for bonding any type of vinyl patch to either Royalex or composite hulls when any type of distracting force is going to be applied. It might hold for a while but will fail IME. Contact cement works great for bonding in knee pads, pedestals, etc. I would not recommend it for D ring anchors for air bags or for knee or thigh straps anchors.

The last hull anchor I popped off as a result of a too taut air bag was one of those old polcarbonate strap-like affairs with a central D ring. It was bonded in with two part urethane 3M structural adhesive which is pretty tough stuff. That was just last October. I bonded it back in place with G Flex.

I have been overall satisfied with vinyl adhesives for vinyl D ring patches but I have yet to find one that I think works as well as Vynabond did. Closest would be Vinyl-tec 2000. But even with Vynabond I expected vinyl anchor bonds to fail after a few years. But I found that if the patches and hull were cleaned up the patches could be bonded back down with the same adhesive. I have used vinyl adhesives to avoid a permanent bond in case reoutfitting was needed, or if I desired to replace a D ring patch because the ring had corroded and rusted.

But there is no doubt that if a permanent installation is desired, G Flex epoxy results in the most reliable and durable bond.
 
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