I have a P&H Scorpio with a running crack. The crack is located on the inside of the cockpit.It appears to be the inner layer of the 3 layer corelite.It Started as 2-3" long crack. The the crack gets progressively longer with use.Has any one else had truoble with P&H plastic cracking? If so, any recommended fixes in dealing with corelite? I talked with the P&H Reps at a kayak festival. They did not offer much in advice.
perhaps drill and fill?
I think I’d drill a small (1/16") hole at the end of each crack, to prevent it from continuing, and then fill the crack and holes with g-flex epoxy. Maybe even put a glass tape patch along the inside, since it’s not going to matter cosmetically.
I agree
Drill at each end of the crack. If the crack is only int he first layer only drill the first layer. I usually use 1/8th inch bit for that sort of stuff. If you want you could drill it today then put tape over it to keep it dry. Bring some Gflex to the symposium and we could patch it for you.
Drill
at each end of the crack. Then tape the back side of the crack if it’s all the way through and apply G-Flex to the outside. I also lay a piece of wax paper over the patch and tape it down with masking tape and smooth that out with my finger. That cuts down on the sanding later.
Thanks
Was thinking G Flex all along. The P&H Reps at the ECKF where not really sure. I hope to have it ready in a couple of days. Luckily, I have a fleet of other Yaks to play with. Thanks and Paddle On.
FrankNC, See you at CKC Sympossium.
Definitely reinforce w/FG tape or patch
I would definitely glue on a layer of fiberglass, either tape or a bigger patch, after you do the repair on the crack.
It’s always a good idea to try & identify the original cause of the crack. If you just repair the visible symptoms but not the underlying cause, it could happen again.
For instance, hull flexing may have been a factor in causing the crack in the first place, especially if there was a thin or weak spot in the middle layer and/or an irregularity in the inner skin.
Drilling & filling the ends of the crack will HELP keep it from lengthening, but if the hull flexes enough, it could pull the sides of the crack apart enough to overrun the reinforcements at the ends.
Gluing a piece of FG over the repaired crack will stabilize and reinforce the surrounding area and any materials defects that caused the crack in the first place.
And there may not be any underlying defect; it’s possible when transporting a kayak to strap it tightly enough to crack and/or deform the hull. This is why I don’t like saddles; J-cradles hold the boat more securely and you don’t have to crank down on the straps to hold it in place. J-cradles also distribute the pressure over a greater area than saddles, which can easily dent the hull.
You also need to be careful with bow & stern tiedowns; the mechanical advantage of pulling down on the ends can easily crack or deform a hull. I’ve seen people who insisted on using ONLY bow & stern tiedowns, which is just asking for trouble.
Anyway, good luck and let us know how you make out.
P.S. G-Flex epoxy works really well on plastic if you follow the surface-prepping directions in the package. You can also color G-Flex with gel-coat colorant to match the color of the boat.
interesting
I haven’t heard of this before with corelite.
Did the P&H boys seem surprised at this?
Not really.
They basically said it was no big deal. It was only the inner layer and would not hurt the seaworthiness of the craft. But, I am a bit OC with keeping my gear working good and looking good. I have trouble letting a crack run, even if it is only cosmetic.
Try this:
On my Scorpio I had great success reattaching the skeg housing to the skeg box (the inner plastic layer) with this stuff:
http://www.polymericsystems.com/epoxies-adhesives/epoxy-putty-sticks/quikplastik.htm
The product lit says it won’t stick to polyethylene or polypropylene, so I wasn’t optimistic, but it’s held tenaciously and rock solid for 2 years now. And it’s very easy to shape.
KP
That sounds very unusual…
I looked at the construction of my Delphin 155 3-layer, and the middle layer does not look like stuff that would develop cracks… It feels flexible. I can see it in a couple of places where there are cutouts made during the construction (the middle layer does not show otherwise). Are you sure it is the middle layer? Or could it be different materials in your Scorpio?
Crack is the inside layer
Crack is in what I call the inner layer. (Visible inside cockpit) The problem is not with the middle/sandwich layer.
I think some of the early Delphins had a problem with cracking the inner corelite. Which is why; I heard, they came out with the single layer Surf Delphins. They have a WW stiffiner down the middle to prevent oil canning.
I got it…
I was wondering how did you see a crack in the middle of the sandwich... Since it is on the inside it should be easier to repair and no drilling through would be needed.
The Delphins are born to be abused, so it makes sense to get a stronger construction for them, hence the 1-layer and the reinforcement beam (which might be there to compensate for the flex of the flat bottom, and/or to minimize the chance of the cockpit collapsing if the boat is pinned). So far, the rocks I've gone over have not had much effect on mine, save for a few scratches. Holding-up fine, knock on wood... In my estimation it would take a really big hit, with strong deflection, equivalent to what would cause serious damage to fiberglass/carbon/the like composite, to create a crack in the 3-layer plastic. I guess one does get these kind of hits in rock gardening - I don't do that and instead run WW with mine, where I do not hit rocks much in a way that would cause big deflection, but I do get hung-up on or slide over barely submerged rocks, so I get more scrapes than big hits and the 3-layer works well for this.