I picked up a used Esquif Avalon for my daughter and boyfriend. The ends have the vinyl worn down to the ABS layer. I want to used Gflex and S-glass to cover the area and act as skid plates. Does this sound reasonable and will it hold well to the Royalite?
The Avalon reminds me of a MRC Explorer but a bit narrower and almost as light as the Kevlar version. Kevlar Explorer is 54 and the Royalite Avalon 59 pounds. The Avalon has a sliding front seat and kneeling thwart which the Explorer does not have. Anyone have any experience paddling this canoe?
First, G-flex may be reluctant to
wet out the very fine strands of S-glass. Do a trial run on a hot day on any old plastic surface. If you don’t get a reasonable wet-out, you should use West 105/205 which is thinner. Either resin will adhere very well to the base layer.
Second, the S-glass layers must be bias cut so that the fibers cross the line of the stem at 45 degrees. This will allow the glass to conform to the convexity of the stem. Do straight cut and it won’t conform well. You will need at least 3 layers of glass, 5 is better, and the largest should go on first, and so on down to the smallest.
I use plastic food wrap and stretchy electical tape over the glass layers before the resin sets. Makes a smoother result and allows you to work some air bubbles out of the laminate.
This is not an easy project, unless you happen to have done similar convoluted work before, plus worked with S-glass. But S-glass is the hardest commonly available fabric one can use, and has good compression strength such as is needed on the stems. Plus it is much more repairable than Kevlar felt skid plate. Good luck.
If you use plain weave S 'glass
– Last Updated: Jan-12-15 4:34 PM EST –
you should be fine. I have used G Flex to do repairs using E fiberglass, S fiberglass, and aramid with no problems. But I have always used plain weave 'glass of either 4 or 6 oz/sq yd weight and I have not tried to wet out more than one layer of cloth at a time.
Some satin weave S 'glass can be reluctant to wet out so I would avoid that. I have used (and recommend) the S 'glass sold by Sweet Composites. Model 6522 is the 4 oz plain weave, and model 6533 the 6 oz plain weave variant. It is not cheap but either comes in 60 inch widths so one yard should be enough to do a multi-layer patch. If you are not worn into the foam core I would think that 3 layers of 6 oz/sq yd cloth would be plenty: http://sweetcomposites.com/Fiberglass.html
If you have not used G Flex before you will find that it is more viscous than conventional epoxies like West System's 105 resin with 205 or 206 hardener. It wets out fiberglass or aramid fine but it takes longer for the fibers to absorb the resin so be patient and allow it to work in. I would avoid doing the repair in cool temperatures. Warming the epoxy reduces the viscosity but also reduces pot and working life. You can also waft a heat gun over the hull which will help epoxy absorption. I find putting a thin coat of epoxy on the hull before laying on the first patch also helps.
I would do the repair basically as ezwater describes. The core of Royalite is ABS just as it is for Royalex. I would remove any acrylic from the area of the hull you want to bond to and rough the surface with 120 grit sandpaper. Next clean it well by washing with soap and water, then rinsing, then using denatured alcohol. I often also use acetone but avoid prolonged contact (or any contact with the foam core) since it does dissolve ABS. Wiping off intact solid ABS is not a problem since it flashes off so quickly.
The instructions with the G Flex suggest flaming the surface of the ABS with a hand held propane torch as an optional step for Royalex. It is essential to do this to get an acceptable bond to polyethylene, but I have omitted this step when repairing ABS and gotten good results. The data West System provides indicates a somewhat better bond after flame oxidation and it is easy to do, but keep the torch flame moving along quickly to avoid overheating and distorting the foam core of the Royalite.
Some people have used conventional epoxies like West 105/205-206 for repairs to Royalex with good results but I have seen repairs done this way delaminate and flake off sometimes months later. These were not repairs I had done and I don't know how good the surface prep was however. But I would use straight G Flex epoxy to bond down the first patch that contacts the hull. If you happened to have West 105 epoxy you could use it mixed with G Flex, or straight, to bond on the remaining patches that go onto the first one since it will bond strongly to G Flex.
To get the best chemical bond it is best to apply the subsequent patches while the epoxy for the prior patch is still at least "green". You can apply all three patches at the same time in quick succession, but again, when using G Flex I would not try to wet out 3 layers of dry fabric all at once. If you want you can then use peelply or poor man's peelply (plastic wrap or waxed paper) so as to get a smoother edge. When I try using wax paper or plastic wrap I always get wrinkles so I either use peelply or nothing. Sweet Composites sells a nylon fabric that will serve as a peelply:
http://sweetcomposites.com/Polyester.html
This is not a treated, mold-release fabric, however, so if you use it you need to remove it while your epoxy is still somewhat green or it may prove very difficult or impossible to get off, short of sanding. If you use this I would apply all my patches in quick succession, then cover with the nylon and work out any air bubbles under it. Sometimes it is necessary to apply a bit more epoxy over the nylon. As the epoxy cures keep trying to pull the nylon off and when the fibers at the edge of the patch no longer lift up you can peel it off.
To get a completely smooth result, whether you use peelply or not, you will want to apply another coat or two of epoxy to completely fill the weave of the cloth. You can then wet sand the patch and further feather the patch edges after the epoxy is fully cured if you want a really nice result.
I like to mix powdered graphite into my epoxy for a job like this. It produces a glossy black (if un-sanded) or matte black (if wet sanded) appearance that presents a nice contrast and looks good with nearly any color boat. You can alternatively paint your patch with spray paint but any scratches will show through whereas the graphite impregnated epoxy will scratch black and not be as noticeable. Either paint or graphite will protect the epoxy from photo-degradation from prolonged UV exposure.
This thread is rather long but it contains a lot of pictures of stem repairs and/or abrasion plates that Mike McCrea and I did on various canoes (many of them Royalex) that you might find helpful. There is also more discussion of technique and Mike presents some alternatives:
http://www.canoetripping.net/forums/forum/general-paddling-discussions/diy/17299-%E2%80%8Bskid-plates-an-evolution
Thanks ezh2o
My experience is I built a Shearwater Merganser from a kit, and repaired a MRC Guide that had a delaminated spot mid hull on the keel line and added a layer of glass over the previous work on the stems. i haven’t used s-glass.
I thought I would use S-glass tape, but have cut bias strips from e-glass for contour work, and it can be hard to get an edge without run out strands. Thanks for the tips and response. I hesitate to do this as i react badly to uncured epoxy. Each time I say not again, but…
This boat was used for 4 years on the rocky lower Saluda and Congaree in Columbia, SC. It just has the colored vinyl worn at both stems. They don’t plan on much WW but well use it on some of the Ozark Rivers and OK.
Wow thanks
So I need to remove all the colored vinyl/acrylic? layer above the light colored ABS in the area to be patched?
I thought I would loosely roll each layer of glass and soak in a small container of mixed s-glass precoat the area to be covered by the glass and then unroll the layer of glass. I have used a stiff bristle brush to poke out pockets of air in woven glass before.
My MR Guide is also devoid of vinyl
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at the stems, but I'm thinking I may be lazy and just put some paint or varnish over the bare spots. I really don't put much wear on the stems of that boat. The wear is from the previous owner. If running rivers like the Saluda or Tyger, I would use my MR Synergy, which has blunt ends and lots of rocker.
If you have to remove much vinyl from ABS, you may be able to speed the process by using a sharp 1/2" chisel, held at a low angle, and at a slight angle to your direction of "push". The vinyl may skim off the ABS right at the junction line, leaving very little sanding to do and avoiding sanding into the ABS. Let's see if I can link to a picture....
https://flic.kr/p/9hZANQ
I would try
– Last Updated: Jan-12-15 5:41 PM EST –
I have heard different things about R-84. Instead of the vinyl color layer bonded to the inside and outside of Royalex, R-84 has a "weatherable plastic" surface ply which I have heard some say is an acrylic material.
I have done quite a few repairs to Royalex boats. When it is easy to do I have removed the vinyl layer so as to bond directly to the ABS. But it is not always so easy to do. Older Royalex boats often develop a rippled surface contour as they age and deteriorate. Trying to remove the vinyl from a concave or irregular surface using a chisel or sanding/grinding without going through portions of the solid ABS can be difficult or impossible, I have found. I have also repaired quite a few livery canoes that I did not own and was not getting paid for my time. In these such cases I did not remove all of the vinyl. I always roughed it up with sandpaper and cleaned it well, however.
I have not had any patches or abrasion plates delaminate from Royalex boats even when the vinyl was not completely removed. I, and others, have also used G Flex to bond anchors to the interior vinyl layer of Royalex boats with good results. But the surface ply of R-84 is different and I don't have any personal experience with how well G Flex bonds to it. So whether it is acrylic or something else, I would try to remove the outer color layer if possible. I know G Flex bonds well to ABS.
The technical support people at West System are quite helpful and they might have some info on how well G Flex bonds to R-84 after surface sanding only.
As to allergenicity, it is only my anecdotal experience but G Flex seems to be considerably less allergenic for me than conventional epoxy including West Systems 205 or 206 hardeners. It is usually always the hardener, rather than the resin, that causes the allergic skin reactions.
The picture shows how the chisel
peels the more flexible vinyl layer from the harder, stiffer ABS. This method should work well on flatter surfaces, but on concave or convex surfaces one would have to be careful to keep the chisel from digging in or rising off the vinyl/ABS boundary.
https://flic.kr/p/9hZANQ
Royalite bonding
I did the ends of my Sojourn, which is royalite. I used e-glass tape and West 105/205, with graphite mixed in. It’s been on there a year now with no sign of delamination.
Use peel ply, you’ll love it.
I recently repaired the stems of my Appy with s glass and West 105. I used the peel ply over only two layers of glass–seemed like enough layers but more are suggested in this thread. Whatever–at least the sunlight isn’t hitting the ABS anymore, and if I need more layers later I can add them. I used the graphite powder.
I did not peel the vinyl off the royalex. I have added several skid plates on different boats and have never removed the vinyl. I had one old boat that the bottom was so beat up I covered the whole bottom with dynel/West 105. There was no peeling off, so I think we can conclude that West 105 sticks to royalex. Removing the vinyl seems like needless work and a risk for damage by chisel.
It was the first time I’d used peel ply and I loved the result. First of all, you get the entire job done with a single application of resin. No having to sand it down and go back later with more coats of resin to get the weave to fill in. Secondly, I got a nice smooth (but textured) result.
On the ends of the boat where the hull curves upward, I couldn’t get the peel ply to lay smoothly. On the second end I cut the peel ply into 2" strips that I laid across the repair like multiple band aids, and taped down the ends. That worked much better. It left little ridges between the strips but they sanded out very easily.
Oddly, Sweat doesn’t sell peel ply. I got mine at Chesapeake Light Craft.
Good luck with your repair.
~~Chip
Good to know, Steve
I take it you did not try to sand or otherwise remove the exterior ply of the R-84?
peelply
Peelply will leave a textured surface because of the imprint of the weave. It is not unpleasant in appearance but for an abrasion plate you might prefer a glassy smooth surface. It is pretty easy to achieve this by applying another thin coat of epoxy after the peelply is removed.
The non-treated nylon fabric sold by Sweet Composites actually works quite well as a peelply I have found, so long as one is mindful not to leave it on too long. How long is too long? Impossible to say since it varies with the epoxy resin and hardener used and the ambient temperature. I generally start checking about 45 minutes after I have finished applying it. I have used this stuff a good bit simply because Sweet doesn’t sell treated mold release cloth, and I usually am ordering other fabric from Sweet for which I have already paid the shipping costs.
Treated mold release fabric is no doubt more convenient and fool-proof to use. There are doubtless many sources for this stuff. Two others are Express Composites:
http://www.expresscomposites.com/vbag.html
and Jamestown Distributors:
http://www.jamestowndistributors.com/userportal/show_product.do?pid=3754&familyName=Vacuum+Bagging+Release+Fabric
Good Info Here
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One thing I might add, however, is that the lighter royalex layup used on Esquif and Novacraft canoes I'm pretty certain is a different royalex layup than the R-84 version seen in boats like the Mohawks in R-84? Especially when you talk about the ends "Wearing" down. My experience with R-84 is that it "Peels" away. I had a R-84 Solo 14 that ended it's life with me with 'glass covering much of the bottom where the R-84 "Peeled" away.
IMHO, the Esquif and Novacraft royalex "Light" (I own a Novacraft Royalex "Light" boat) models will not be nearly as much of a headache to repair and maintain as the old R-84 layups I've worked on in the past. I think you picked up a good boat?
Royalex light, Royalite, R-84, R-lite
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I am pretty sure that Nova Craft's "Royalex light" is just a thinner sheet of regular Royalex material with vinyl bonded to the inside and out.
Dagger called their light weight material R-lite. I think it was R84 but I could be wrong. Steve Scarborough of Dagger canoe says a few words about R-Lite here:
http://groups.google.com/forum/#!topic/rec.boats.paddle/cOeoXX8-usk
I believe that there were various versions of thermoplastic material that were called Royalite (which is a registered trade name) but I think that all of the Royalite material used for canoe construction was Royalite R84. If anybody knows this to be incorrect, please chime in.
Here is a spec sheet from Spartech, erstwhile maker of Royalite R84:
http://dss.polyone.com/docs/Royalite%20R84.pdf
Esquif calls their lightweight thermoplastic material "Royalite" so I assume it is Royalite R84. I have not worked on an Esquif Royalite canoe but I did demo an Esquif Royalite Spark whitewater boat. I noted some of the flotation bag anchors had come loose from the hull interior which was also a common problem encountered when outfitting the Mohawk R84 whitewater boats. The interior and exterior surface ply of this stuff is not vinyl, and many of the adhesives commonly used for whitewater outfitting of Royalex boats does not bond to it reliably.
For small jobs, food wrap has always
worked well for me. I can see bubbles under the film if they need to be worked out, or dry areas where the resin hasn’t fully penetrated. Flexy tape pulls the layers of cloth together and squeezes out a bit of excess resin.
I tried the Sweet product, still have some of it, but it is too stiff for the small patching jobs I do.
I recommend that people try food wrap film to find its limits before jumping onto the peel ply wagon with both feet.
Thanks Steve
I also have a R-Lite Dagger Sojourn in off-white color. It has factory wooden gunwales. I LOVE the canoe and will soon have to make stem repairs as the light green layer under the exterior color layer is showing a little. One thing about Daggers method of manufacture in their R-Lite canoes is that I find them to be very rigid and stiff compared to all other brands of canoes made of Royalite or R-84. I have owned quite a few Mohawks and Wenonahs and others in this material and they are much more flexible and the Wenonahs seemed actually flimsy!
OH BTW
BTW I was actually the guy that directed Castoff to the place selling the Avalon. We were meeting there to look at a Kevlar MR Malecite that needed some minor work but the Avalons caught Castoffs eye. After we had lunch and he thought about it,… he went back and bought it but not before he convinced my to buy a nice 18ft SOT Sea Kayak at another outfitter a few miles away. It was a very memorable day for us both.
Roughed it up a little, Pete…
…but didn’t remove any skin.
Of course, it’s not a whitewater canoe so I’m not bashing it on boulders.
Roger that
The Dagger /Wenonah thing, I mean.
So…who got the Malecite?
Nm