I am wanting extra flotation in two 17ft OT Trippers. We are beginning to paddle some very mild WW but still do mostly camping out of the canoes. My question revolves around whether to lace the entire length under both gunnels as tie off points for flotation cages or many D rings. There are five in our family so someone is sitting in the center, so I am unsure if a center bag is possible but thought the lacing would provide more options for tying off gear as well. Should I buy the air bags first to see how much room they take up and where anchors should be located before making the decision?
Thanks
canoe floatation
Vinyl backed D rings have gotten rather expensive so using “many” of them can be an expensive proposition. Keep in mind you will also need to buy vinyl adhesive to bond them in.
I am assuming you have Royalex boats rather than the three-layer roto-molded poly Trippers that were around 17’. The distinction is important because most conventional adhesives will not bond well to polyethylene. If you have poly boats, West Systems G Flex epoxy will work, but you must flame oxidize the hull surface first by quickly passing the flame of a propane torch over it.
With a tandem boat like a Tripper, you will most likely only be able to use relatively short tandem end bags that tend to be about 3 feet in length when inflated. Yes, definitely get the bags first. Don’t go by the length stated by the manufacturer. The listed dimensions are for the uninflated bag flat, and all bags will be shorter when inflated. How much shorter depends on the shape of the canoe and the volume of the ends.
You will definitely require some type of lacing to keep the bags in the boat. Although canoe flotation bags generally have either grommets or nylon webbing loops built in, do not rely on these to hold the bags down inside the hull. For one thing, the grommets often tear out when under tension. Secondly, water in the boat will simply go under the bag and float it up outside the hull, even if the bags are secured down at the corners.
For any gear in the boat I would strongly suggest restraining it either under lacing, or attached to anchors bonded to the hull bottom. Do not secure gear only to thwarts or some anchor point up near gunwale level. If you do, if you capsize and the boat is inverted, your gear will hang down in the current. This greatly increases the risk that the boat will get hung up, complicates getting the boat over to shore through the shallows, and renders a canoe boat-over-boat rescue difficult or impossible.
For tandem end bags I would construct a bag cage as long as the inflated bag with lacing strands running transversely about 4 inches, but not more than 6 inches apart. I would also use a “keeper strap” of 1 inch wide webbing (nylon, polypropylene, or polyester will all work) secured at the stem of the boat, running down the keel line, and secured at the other end to a D ring anchor bonded to the hull bottom. The keeper strap will help keep the bag up in the stem, otherwise water in the boat will try to float it back toward the center.
You might have room for a smaller center bag. If you use waterproof packs, dry bags, or barrels to haul gear they will also provide some flotation so long as they are restrained in the boat.
The lacing I usually use for a bag cage is 3mm nylon accessory cord. The easiest way to rig it is to simply drill a series of holes through the hull just below the gunwales to weave the lacing back and forth across. The only disadvantage to this method is that if you need to remove the lacing it is somewhat laborious. You can also buy some nylon “inchworms” or “pad eyes” available from a variety of vendors, and secure them to your gunwales using stainless sheet metal screws. It is quicker and easier to lace and unlace a bag cage using these.
If your boats do not have end grab loops I would strongly consider adding some by simply drilling holes through the hull about an inch below the deck plates and about and inch and a half back from the center of the stem. Either synthetic rope or 1" wide webbing can be used for a grab loop. Tie the loop off using a fisherman’s or double fisherman’s knot for rope or a water knot for webbing. The grab loops will be a much better location to secure a painter then the carry handles built into the synthetic deck plates.
My preference is to lace full length
If you end up in a bad situation at some point where the gunwales are torn off the canoe the lacing may help to maintain some structure in the hull - at least theoretically. It will also provide extra tie in locations for other gear if you need that.
https://photos.google.com/album/AF1QipMDASeuzS--NImSTe3yBhA2vhni_MMNCcs4GInq
rigging
Your gear functions like flotation on overnight trips. For mild WW, you do not need to add flotation. For day trips in harder WW, you can add flotation bags.
Tying down packs
As mentioned, your gear packs will provide a fair amount of flotation. They are not as good for that purpose as air bags, but they aren’t too bad and there likely won’t be room for both in the same part of the canoe at the same time. Packs are best tied to anchor points on the floor. They can be tied down very securely that way, so they won’t budge at all. Gear packs positioned under gunwale lacing will be free to slide around, and though you could rig up ways to keep that movement to a minimum, it’s better to just tie them to the floor and be done with the problem. It will also simplify loading and unloading the boat since most types of gunwale lacing are tedious to lace/unlace, and slipping the packs out from under the lacing end-wise will be prevented by the front seat, and most likely by the middle thwarts as well.
Lacing
Didn’t get to open your links but to make I’m on the same page, lacing full length down both sides, then bag cage lacing back and forth thru inner side loops correct?
check this out
– Last Updated: Aug-09-15 3:02 PM EST –
This webpage describes the manner in which most whitewater open boaters I know construct a bag cage. It also shows how to install end grab loops:
http://www.tworedcanoes.com/canoe_endbags.php
The bag cage lacing is essentially one long length of 3mm accessory cord that is laced back and forth across the hull. The cord runs from one hole to the next farthest from the stem on the outside of the boat just below the gunwale.
The keeper strap is secured at the stem using a loop of 3mm cord inserted through the grab loop holes and tied to itself inside the hull using a fisherman's knot. The 1" wide webbing wraps around the cord and is secured to itself using a nylon Fastex triglide like this:
http://www.fasteningsystems.com/tri_glides_and_d_rings.html#tg
The bag cage shown is a bit more elaborate than you might want, using three hull bottom anchors at the central end of the bag instead of just one. The "W" shaped arrangement of the accessory cord keeps the bag corners from "pooching" out around the keeper strap very nicely, but you can get by using just one anchor to secure the inboard end of the keeper strap and making a "V" shaped arrangement of cord to help secure the bag.
The only disadvantage of this type of arrangement is that if you need to remove the lacing it is a bit of a chore. However, in a tandem boat with a tripping load you really don't want to be putting gear way up in the stems of the boat anyway.
If you construct a central bag cage to restrain gear or a center bag you might want to use the nylon pad eyes like these secured to your gunwales with stainless screws:
http://www.austinkayak.com/products/223/Nylon-Pad-Eye-Ea.html
I use this type of arrangement in addition to a nylon keeper strap to restrain packs and barrels in the central part of a tandem canoe. The lacing is very easy to undo and re-thread through the pad eyes. It is not generally necessary to completely remove the lacing to get gear in and out, just partially undo it.
To re-thread and tie the lacing over the gear takes less than a minute.
Yes,
gunwale lacing is a larger diameter cord. Bags are laced in separately.
You could do both
You could set up the center part of the boat for lacing, and put a few D-rings on then floor. That way it’s ready for using a center air bag if you want, and also for tying packs of any size quickly and securely to the floor.
If packs inside the boat are free to shift around when the boat is swamped (which will be the case with lacing unless the packs are quite large), the boat will sit lower in the water and also roll about larger radius than if the packs are secure. That won’t matter a lot of the time, but if you are unlucky it could be what leads to a pinned boat. In any case, having both lacing and anchors on the floor would provide the best of both worlds. One person here once described putting packs underneath air bags, and that would work a lot better if the packs could be tied down independently of the bag (it may not be something you would try, but I’m putting the idea out there).
At least do the lacing if you want to be ready for whitewater daytripping.
In Maine
people who day trip add a truck inner tube on class 3 and more.
Not on class 2 like the Allagash.
The Tripper is a fine poling boat, standing the poler does not use airbags in the center and I have never seen them in the ends either as there is not much footroom in front of the bow paddler.
You can do what you want and feel comfortable with but Trippers are the most used boats around my parts for tripping and I have never seen any outfitted with bags and packs too.
of course
Measure the hull for your chosen airbag after fitting in NRS DRY bags with the backpack straps…if affordable*
https://www.google.com/#q=canoe+floatation+air+bags&tbm=shop
http://search.nrs.com/search?w=dry%20bags
I have Solo equipment so following this I total out for 2 on 17’
With a large touring kayak fitting in a sleeping bag is tightx2
What paddlers do with 2 bags ?
Basically, spending $200+ bucks keeping the essentially dry equipment DRY is bottom line.
The dry bags are attached to the hull with d-ring patches and straps maybe 8 per bag for up to class 3.
Basically there’s no gain in watching your $100 bag with $200 insides go down the chute without you.
While you’re there buy 2 floating painters at walmart n stroll thru the boating and rope sections. Rope or cord on the black holder is very good.
Imagine shopping across the boards for canoe floatation? Wenonah has bags too….call.
*humour
410 Stainless Screws
http://www.mcmaster.com/#tapping-screws/=yfed22
buy 2 correct bits in jobber lengths…search MC
and a shorty screwdriver to match
you have a bit/screw chart copied ?
there is maybe here scuttlebutt abt hanging the hull upside down facilitating screwing gunwale bottoms. An idea worth considering achieving more accurate work than bending over.
look at these hull holes
eees drilling holes in the hull.
drill holes vertically down thru or up thru the gunwale
then drill several holes thru the hull below the waterline for grab loops.
nutcase !
Thanks
Thanks for all the replies so far. I’ve never seen an air bag up close and it’s hard to put it all together from just on line articles but I think I have the jist of it. Just didn’t want to drill unused holes in the hull. I know, air bags in a tripper seems anti Bill Mason, but the people I’m paddling with brought about a good point that it’s not just for us but for other’s safety who may not realize the weight of a swamped 17 ft canoe and go chasing after it. I think they make a good point. So now just got to get it sorted out to make as few on line orders as possible. The flip side is even while camping on still water, our packs will be secured much better and safer than just tying to a thawrt as we had been doing. Can’t wait to get it done and get into a little bigger water.
you are correct
Whether or not you “need” supplemental flotation in your canoe has nothing to do with what class of whitewater you intend to paddle. If you are absolutely certain you are not going to come out of the boat you don’t need it. If you do swim, the more you have the better. The same could be said for your PFD. It serves no purpose if you don’t swim.
Swimming a heavy, swamped tandem boat out of current can be a pretty daunting task and most Royalex boats when fully swamped have only enough inherent buoyancy to keep just a small percentage of the hull out of the water. Obviously, the difficulty of rescuing your boat, or losing it, goes up with the difficulty of the water you are paddling, but it is quite possibly to trap a boat under, or wrap a boat around a strainer even in moving flat water. I have seen it many times and it doesn’t even require a rapid.
Over the years I have struggled to rescue or help rescue many canoes and kayaks that were barely afloat because the paddlers (now swimmers) knew they did not need flotation.
You’re all over it.
Pete beat me to it, but his advice comes from much more experience and is spot on as always. FWIW when I added bag cages to my tandem boat (sixteen foot Explorer) I used the little plastic D rings that come in a kit from NRS. Worked/works fine, but if I had it to do over again I’d just drill the hull. You’ll be glad you did this.
Bags definitely take up room
My Mohawk tandem with end bags and center bag:
http://www.flickr.com/photos/eckilson/15022105611/in/album-72157646414123078/
This was done with metal pad eyes for the lacing. If I had to do it again I would just drill holes under the gunwale. I leave the end bags in all the time. The center bag only goes in for whitewater runs. The center bag has a D-ring at each corner that could be used to tie down gear.
I drilled and laced 3/4 of sides
Left middle unlaced and use D-rings.
I have 16’ tandem and don’t take airbags out all the time, but can if I need too. The air bags pack down small too…so you can start with them packed, and if you decide later you need them…just inflate and attach.
I practice swamped my Rx boat with and without the bags. Ultimately had to swim the canoe to shore without the float bags. I was able to re-enter with bags. If I had gear…maybe it would be a different story?
And if things were to get really bad in the backcountry, I will have several yards of line to make shelter, etc…
air is cheap until you try to contain it
– Last Updated: Aug-13-15 1:23 PM EST –
Since my last post, I did a little measuring and found that the Harmony Center Bag could work with 3 people in the canoe. Here's the skinny-
Center 37"x32"
Nylon $120 & 1.6 lbs
Vinyl $75 & 3 lbs
Ends 28"x33"
Nylon $80 & 0.7 lbs
Vinyl $50 & 1.25 lbs
I figure I would have about $360 per canoe with nylon bags and D-rings and such...x 2 canoes and that's some expensive air. (Floatation would cost about 23% of the canoe) There was no dimension given for the height, but assuming 15" deep, 2 end bags & a center bag would displace about 18 cu. ft. or 1120 lbs of water. For the 3 bags, nylon would would cost about $280 or $0.25 per lb of water displaced, and vinyl $175 or $0.16 per lb of water. I thought I could get away much cheaper by building fitted blocks from expanded styrofoam sheeting (rigid insulation from lowe's) and covering with something to make it more durable. But it works out to $0.10 per lb of water and according to what I found on line, density is about 1 pcf. Therefore same volume of styrofoam floatation would weigh 18 lbs vs 3 lbs for nylon bags. So, back to air...are both the vinyl and nylon about the same when it comes to wear and tear and I'm paying for the weight savings of nylon? Or is the nylon more durable also?
Pounds of displacement …
– Last Updated: Aug-13-15 1:02 PM EST –
... is not all that important in the final analysis. Unless the boat is somehow pushed below the surface and is held there, the bags will never displace that much water and thus provide such an enormous flotation force. What will actually happen most of the time is that the canoe will capsize and only sink to such depth that the bags displace the total weight, which is a very tiny fraction of that 1000+ pounds that you quote. If the canoe is partly full of water and upright, larger bags help more, but again, you won't see a thousand of pounds of water being displaced. Further, if the canoe is very full it likely will tip and dump a lot of that water. In short, filling as much interior space as practical makes sense, and more is better, but calculating how many pounds of flotation those bags *could* provide if fully submerged is meaningless.