Need some help, this weekend, while hauling my Old Town 119 Guide, the strap holding it in the trailer came loose and it was dragged down the road causing the outer layer to be ground off down to the foam, about 1" X 4". In reading some other post, I saw where some had used JB Weld Marine. I was also looking at Kevlar Skip plates from Northwest Canoe Company.
Also, in reading on Old Towns site and also the Northwest site, they both said to polarize the plastic prior to repairing to help with adhesion.
Suggestions please
epoxy
Smear a bunch of epoxy over the affected area. I’ve had good luck with epoxy sticking to poly canoes. Get the quick-set stuff by LOCTITE. WalMart has it.
Worth a try anyway…
polarize ?
Is polarizing torching the surface ? I’m not sure this is a good idea with foam. Your hull is a plastic/foam/plastic sandwich ?
But a patch overlapping foam onto the original surface, which is not foam, may need torching as Old Town recommends.
The patch would lap onto plastic over foam maybe 1.5-2"
Or you may skip the patch slathering epoxy over the foam. This repair is brittle, probably crack out.
So if the foam would be damaged by heat then a thick aluminum foil cover strapped down with tape is protection but watch the loose edges.
Of course, this is speculation, as I don’t know the material.
I’d buy Old Town’s repair kit if price is reasonable compare to
https://www.google.com/#q=west+marine+plastic+boat+repair&start=20&tbm=shop&tbs=vw:l
Skid plates are useful for rocky seasonal streams but caws drag in long pools. The skid patch glue is the repair glue. On stern ? try the plate but you need to bring the gouged surface up to un-gouged spec.
and , of course buy a rack !
Rack?
He has a trailer. He doesn’t need to buy a rack. He only needs to buy some good cam straps that don’t come loose, but I digress. G-Flex epoxy should give you good results.
epoxy and polyethylene
– Last Updated: May-30-14 9:35 AM EST –
I have not had good results with getting conventional epoxies to durably bond to polyethylene boats. I have seen some repairs done to Old Town Discovery boats with cloth and conventional epoxy that failed pretty miserably, others that held up for a short while then began to delaminate. Rest assured that any unsuccessful repair you carry out will make it more difficult to do a proper repair later.
I have heard of quite a few people filling in exposed foam core of plastic boats using either JB Weld or Gorilla Glue but that has been on Royalex boats in which the exposed material was ABS plastic. Polyethylene is much tougher to bond to.
The best epoxy for use on polyethylene is West System G Flex which will bond to polyethylene if the surface is properly prepared. Unfortunately, it is somewhat expensive. You can buy a relatively small quantity in a kit like this:
http://www.nrs.com/product/2271/gflex-epoxy-repair-kit-650-k
Ignore the fact that the label refers to "Aluminum Boat Repair Kit". This kit also includes colloidal silica powder which you can use to thicken the epoxy to fill in the void that was created when you wore off the outer solid layer of polyethylene. The epoxy mixes easily 1:1 by volume (resin:hardener) and can be mixed by eye in whatever quantity you want so you don't need to buy minipumps for the epoxy.
Yes, it is critical to prep the surface of the polyethylene to achieve an adequate bond and this involves temporarily oxidizing the surface by passing the flame of a hand held propane torch quickly over the surface as described in the information on the Northwest Canoe Company site.
To repair the abraded area of your hull I would first remove any portion of the solid outer layer of polyethylene that might have detached from the underlying foam core. Bevel the edges of the outer solid poly layer by sanding. Remove any dirt and grit from the exposed foam core using soapy water (Dawn dishwashing liquid) and a scrub brush and rinse well. Make sure that the area of exposed foam core is dry. Give the area to be repaired a final cleaning with denatured alcohol and let the alcohol evaporate completely.
When you oxidize the surface you must be sure that the inner blue cone of the propane torch flame just touches the hull surface. You want to move the flame along fairly quickly to avoid deforming or melting the hull. Any area that you want the epoxy to bond to must be flamed. Apply the epoxy within 30 minutes of the oxidation process if possible.
Mix up some G Flex and stir in some silica powder to thicken it to around a mayonnaise consistency. The epoxy will settle down into the foam core and you will have to apply more. You can put more thickened epoxy on while the first application in still "green" (partially cured). If you apply more epoxy over cured epoxy, wash the cured epoxy first or wet sand it to remove amine blush.
It might take several applications of epoxy to build the damaged area back up flush with the surrounding hull. What you are doing is rebuilding the outer layer of solid poly that is gone and replacing it with thickened epoxy. You will probably need to "overbuild" the damaged area with epoxy (much like you would with wood putty) then sand it down smooth and fair with the surrounding hull.
If you do not choose to add abrasion plates cover the cured epoxy with some spray paint that more or less matches your hull color to protect it from UV exposure. I use Krylon Fusion but anything will work.
If you choose to use the Northwest Canoe Company skid plate kit I would call them and ask some pointed questions about what the success rate has been applying them to poly canoes. These kits usually use a two part polyurethane adhesive. I have seen some kits like this work well on poly canoes and I have seen others shear right off. Of course, those that failed may have been a result of inadequate surface prep.
If it were me I would buy precut Kevlar felt skid plates without adhesive such as:
http://www.harmonygear.com/products/9765/Harmony-Kevlar-Skid-Plate-Felts-for-Composite-Canoes.html?utm_source=feed&utm_medium=cpc&utm_campaign=GoogleHG&gclid=CMqd_YLY074CFQcSMwodOjsAgg/
and apply them using G Flex epoxy. The amount of epoxy in the 650-K kit I referenced earlier might not be enough to both repair the hull and apply the skid plates. You can buy 4 oz quantities of G Flex resin with 4 oz quantities of hardener without the dodads that are included in the kit a bit more cheaply:
http://www.nrs.com/product/2270/gflex-epoxy-650-8-kit-2-4oz
I would find a good plastic welder.
That person will know how to fill in over the exposed foam and bond new poly to fill the gap.
Whitewater paddlers in your area should know where you can find a good plastic welder.
On the skid plates, I’m not sure they would be worth the hassle. Kevlar felt won’t stick well and is likely to crack and break off.
There is a “new” approach akin to plastic welding which can be used to add poly thickness to “skid” areas. A hot soldering or tacking iron is used to iron pieces of ordinary woven plastic tarp onto the hull surface. I’ll have to try to find the link again.
old town vs west systems ?
Old Town’s repair kit repairs polyethylene AND vinyl.
West’s 655 repairs polyethylene not vinyl. In this category, vinyl glues do not repair polyethylene.
http://www.westsystem.com/ss/gluing-plastic-with-g-flex-epoxy/
Kevlar skid plate cloths are mesh. Wetting the mesh would stick the cloth to polyethylene if the glue/epoxy was meant to stick there. Unless the mix was rejected by Kevlar, unlikely - you could here the screaming no problem.
I get the idea OT’s works but West’s is best ?
Not an absolute.
Old Town repair kit
The Old Town repair kit uses a two part polyurethane adhesive much like that (and quite possibly identical) to the polyurethane adhesive that comes with the Northwest Canoe Company skid plate kit. As I said before, I know some folks who have had good results using this type of adhesive on polyethylene, and some who have not. Those who have had failures might have done inadequate surface preparation, but I don’t know.
I would not trust Old Town’s assurance that their kit will work well. Old Town has also marketed a methacrylate adhesive repair kit for their poly boats that I know has failed miserably for several people even when used exactly according to directions.
The problem with using a polyurethane adhesive for this type of repair is that the adhesive comes premeasured in two cans that are mixed together all at once. It might be possible to try to measure out smaller portions of the resin and hardener volumetrically but it might not be that easy and I don’t know how well the unused portions last after the cans are opened.
To fill in the void created by wearing through the outer layer of a three layer poly boat and exposing the foam core might require four or five applications of relatively small batches of epoxy. West System G Flex epoxy works very well for this because batches can easily be mixed up in any size including very small.
Even if the Old Town Repair kit could be made to work, it is ridiculously expensive. Most vendors are asking around $100 for it. Precut Kevlar felt skid plates and sufficient G Flex to repair the hull and install the skid plates can be purchased for less than that.
G Flex bonds just fine to vinyl, by the way, and I have used it for that purpose. But whether it bonds to vinyl or not is not an issue in this case. There is no vinyl involved in either a three-layer polyethylene hull or a Kevlar felt abrasion plate. And Kevlar felt is not a “mesh” exactly. Like all felts, it consists of compressed short fibers, in this case aramid fibers. And G Flex bonds to aramid just fine.
West
I agree. Important getting the right West numbers for polyethylene.
For example, 650 does not glue plastics but 655 does.
Glued a tool pouch with leftover vinyl from a floormat tub application. Holding 10 pounds tools with a 1.5" seam is no problem for standard vinyl glue.
Glued a cracked Walmart 5 gallon bucket with Locktite plastic epoxy. Holds.
Specificity in glues with current chemistry. Outstanding !
If searched for the subject in Google shopping , there are putty epoxies use able for possible below level gouging.
G Flex kits
– Last Updated: May-31-14 6:58 AM EST –
Actually the resin and hardener used in G Flex 650 and G Flex 655 is the same. The stuff in the 655 packages has just been prethickened with silica powder.
The "K" appearing after 650 or 655 simply denotes "kit" meaning that some additional gizmos are included with the epoxy and hardener.
For reasons that are unclear to me, West System has confused the issue by deciding to relabel the 650-K kit "Aluminum Boat Repair Kit". It does work on aluminum but works fine for the same plastics that 655 works on.
Thickened epoxy is better for bonding together cracks, filling and sealing holes, and fairing. But unthickened epoxy is preferred for wetting out cloth. The 650-K kit includes silica powder so you can thicken the epoxy as much or little as you like for bonding and filleting.
http://www.westsystem.com/ss/g-flex-epoxy/
There are some "elastomer" adhesives that will bond to polyethylene and allegedly even to polypropylene. Here is one:
http://mrstickys.com/poly-tank-repair-kit-manual-mix/
Note that the manufacturer describes this adhesive as "rubberized". The bit about this being the only glue that will bond to HDPE is BS.
I have not used that type of product but my concern is whether or not epoxy would bond to it if you needed to do a cloth repair over it.
Kevlar skid plate cloths are not "mesh"
Kevlar skid plate kits supply Kevlar felt, which is not a mesh at all.
Those of us who use “mesh” for skid plates are using bias cut S-glass or E-glass cloth.
You keep injecting yourself into these discussions as if you know what you are talking about, but instead you only raise a lot of dust and a lot of detail errors that we have to correct.
?
the words mesh and felt are interchangeable here as the epoxy bonds to itself around the mesh then onto, we hope, the hull both skin and foam.
My Rendezvous has Wenonah skid plates…the ‘fabric’ is ? as I forgot to note that for your information. The Wenonah ‘fabric’ is very cohesive, integral, well hooked together and thus not very ‘felt’ like.
I’m not sure ‘felt’ is an adequate word for the material from Wenonah as voids for wetting out are NOT felt like.
Your explanation of 650/655 leaves me confused as clearly the directions here on 650 say NO PLASTICS…no polyurethane ? I’ll check again when the garage opens.
My point to the poster was buy specifically for polethylene, be sure of your numbers and product applications.
As you read here, and as I’ve noticed in the store or online. when the chemistries apply to different materials in different degrees, we see some mislabeling …for our use if not for common household uses.
As the chemistries for nylon or polyethylene’s firm up and separate from steel wood rubber (!), then we read more specific advertising.
Beware vaguenesses. Double check online.
I research the subject and write during meals not claiming expertise but participating in a conversation of information.
If you want to clean something try your basement.
They are not interchangeable.
You need to stop pretending to knowledge you don’t have. If people seeking help here were to follow your advice, many of them would be screwed. But I don’t think that will seriously bother you, because from the moment you appeared on this board, it has been clear you are mainly interested in getting attention, not helping.
You haven’t even managed to keep track of whether you are replying to me or to pblanc.
Felt or Fabric is ‘meshed’
Looked that up in Visual Thesaurus.
Wenonah uses ‘felt.’ felt ‘meshes.’
This is a conversation not a trial.
You flame.
NRS Old Town
NRS follows Old Town’s position:
http://www.nrs.com/boating_tips/quick_guide_gflex_epoxy_adhesive.asp
Local noise chimes in with that aluminum gives stickiness onto the polyethylene.
Missing the point
You can’t re-define the method by which a material is constructed, or claim that the name for said type of construction is irrelevant, simply based on the new character the material takes on once you’ve combined it with something else. It’s clear you have no clue what you are talking about and are backtracking in the best way that you can by attempting to minimize the nature of the facts by which you’ve been shown to be wrong.
You speak of your own canoe’s factory skid plates with an air of authority, as if that’s relevant, and invite people to “look it up online” (the way you did), but Pblanc and ezwriter don’t need this kind of “help” from you to know what’s what. Their experience is decades old and hands-on, not looked-up because the need arose before stepping into a discussion. You’ve owned what, two canoes (one being aluminum), and have done how many repairs yourself? Whole fleets of canoes have been repaired and even brought back to life by these two guys whom you are only too eager to claim don’t know their stuff.
This is hardly the first time you’ve responded to challenges to your “knowledge” by saying ‘look it up online’, and there’s even been a case already where you defended a totally-wrong conclusion by pointing out that a list of references pops up when certain key words are entered into a search engine, but you never checked to see that the subjects of those articles were irrelevant. The nature of this exchange is similar.
to join together
the poster asks for suggestions…
How does plastic welding compare to current polyethylene gluing standards ?
I used a soldering iron on a Wheeleze tire, after checking on line. Tire inflates ! Amazing.
Any testimonials ?
depends on the polyethylene
Thermal welding can yield excellent results with single layer, linear polyethylene boats. Most of today’s polyethylene kayaks and canoes are made of linear polyethylene. Thermal welding does not work with cross-linked polyethylene. Unfortunately, many poly kayaks from the 1970s, 1980s and early 1990s were cross-linked polyethylene.
Linear polyethylene melts nicely at around 400 degrees Fahrenheit. Cross-linked polyethylene starts to spark and then bursts into flame before it melts in a controlled fashion.
I have not heard of people repairing three layer polyethylene canoes or kayaks with thermal welding. That doesn’t mean it can’t be done, or hasn’t been done. It just means I don’t know anyone who has done it or had it done. I heard about one guy (an ex-professional welder) who could apparently successfully thermally weld Royalex, which has a foam core somewhat similar to three layer polyethylene canoes (although a completely different material). He used industrial welding equipment. If that could be done, it seems reasonable to assume that three layer poly can be thermally welded.
My experience with oxidizing three layer poly hulls using a propane torch prior to bonding with G Flex epoxy suggests that this would certainly not be a job for a first-timer to attempt. My experience was that the foam core of three layer poly was rather easy to carbonize and blister with overheating.
foil
– Last Updated: Jun-01-14 8:39 PM EST –
I cover not to be heated parts with layers of aluminum foil...Shimano grease seals...nearby gaskets/tubing/paint. When heating to fragment red locktite.
The plastic flaming is but a pass of the torch ? so foil lapped over the poly to a 2" flamed overlap area suffices.
And the industrial welder ? who inspected the foam after welding ?
Google Shopping searching on: 'plastic welding equipment,'' plastic poly sheet/film welding rod' material and of course : 'polyethylene kayak welding' yields a utube video
and for 'plastic kayak welding forums' where the question is asked "I dropped my Old Town off a trailer at 80 mph...
I remain suspicious of the entire process even after 40 years of looking at the stuff but in those searches I see welding equipment specifically advertised for off road body parts, a more demanding market .
No, it isn’t. Mesh is woven and felt is
not.
ESOL