Freestyle Carbon Kevlar Rickter FS-2

[Dirtbikeking42]

I’m building my first “flat water ski” or just rec ski also. It’s an old wammer hull that was abused and needs a lot of work. Not trying to jump your post but just gunna follow along to get tips for carbon and Kevlar repairs!!!View attachment 452512

I’m building my first “flat water ski” or just reck ski also. It’s an old wammer hull that was abused and needs a lot of work. Not trying to jump your post but just gunna follow along to get tips for carbon and Kevlar repairs!!!View attachment 452512

 

[Diametunim]

I absolutely LOVE the look of that Kevlar, the strength of it , and the flexibility of Kevlar.
I ABSOLUTELY HATE that Kevlar when it comes to working with it.
Kevlar does not cut clean , even when it’s encapsulated in resin epoxy. It was properly applied in one of my builds in the tray area, perfect area to use it, lots of flexing going on in the tray. I had to cut thru it to install footholds, and even with a cut off it doesn’t really cut, it more like burns. And it doesn’t sand for chit. If I were dealing with that hood I’d probably just lightly sand a little around the chip, you don’t want to fray that Kevlar, and lay some UV inhibited 2:1 clear on it, buff it and polish it in, and call it good. Cured 2:1 is pretty flexible, should stay attached while preserving the original look.

Thanks for the information about working with Kevlar. I'm really going in blind here so every bit of information helps, even if it is disheartening to hear that Kevlar can be a pain in the ass to work with. In the end I think I'm going to end up working with Kevlar regardless, you'll see why here in a bit. I'm still on the fence on whether or not I want to try and lay Carbon / Kevlar down in the interior of the hull or stabilized carbon because it's easier to work with and I won't have to worry about fraying the material as I work with it.

Didn’t see that last pic, maybe some chopped carbon, epoxy and cabosil. Build it bigger , sand it back, flip it so it’s hanging down , clear UV resin build up hanging off the corner for a finish.

How would you recommend I sand around the chip in the hood? Would I be safe hitting it by hand with 220 grit or should I hit it with a sanding disk on the Dremel? I do like your advice on mixing up epoxy, chopped carbon, and cabosil. When working with Cabosil is there anything I can do to maintain the clear color of the epoxy? I assume that mixing cabosil into epoxy will turn the epoxy into a white slurry similar to adding corn starch to food.

Keep an eye on the pump alignment with that 148mm Torrent

Any particular reason you aligning the pump out? I was able to get the pump aligned spot on in my SJ hull using the Cold-Fusion alignment tool though it did take quite a while to get correct.

 

[Diametunim]

Time for some quick updates. Using a hammer, chisel, and a Dremel with a 9905 Carbide Bit I was able to knock all of the old inserts out of the hull without too much trouble. Turns out that epoxy doesn't bond to stainless steel so the "bond" truly comes from the epoxy encapsulating the mount. I started by knocking the large globs of epoxy from the circumference of the mount using the hammer and chisel. I used the 9905 bit for detail work where needed to grind out any leftover epoxy keeping the mount glued down. The 9905 bit was also a godsend when clearing out any small bits excess epoxy from around the hull.

Cleaning up the excess epoxy from throughout the hull was easy enough. Again, liberal hammering combined with the chisel was enough to knock the large pieces of stuck epoxy off the hull. Just be cognizant of where the head of your chisel is in order to ensure you're not going to dig into or damage the hull as you whack on the chisel. The remainder of the detail work was accomplished with the 9905 bit mentioned above and 1 inch sanding discs on my Dremel. I worked with several grits ranging from 80-220.

There's quite a bit more more detail and prep work to be done but my plan overall plan is to finish the interior of the hull in carbon Kevlar or stabilized carbon. to reinforce the bottom of the hull as well as clean up blemish marks leftover from removing the old UFO mounts.

 

[Diametunim]

Lets finish stripping the hull. I've never done turf before and now that I have I cannot recommend an oscillating tool enough. I picked up a cheap oscillating tool off Amazon for this job and so far so good. The chisel attachment combined with the sanding heads have made "quick" work of all of this.

I can't imagine having to do this poop by hand.

Just gonna leave these here.

 

[fastgtfairlane]

Does the tray have foam in it? If not then repairing the cracks shouldn't be too bad.

 

[Diametunim]

No foam under the tray at all. It's completely hollow. At this point though I think I'm at the point of cutting the tray out, re-sealing everything under the tray, possibly replacing the rideplate & pump inserts (because why not I'm there), adding foam and reinforcing the tray. Anyone have any arguments against adding foam? Based on some very quick googling I think I will need roughly 5 cubic feet of foam to fill the tray (I'll calculate the volume shortly) if I used a 2lbs density , 2-part closed cell foam like Sharkthane I should only add ~10 lbs to the hull while greatly increasing flotation should I ever sink the hull.

 

[fastgtfairlane]

If it were me I would not foam the tray. Your tray will start leaking at some point and youll end up with a waterlogged tray. I would imagine there's some stringers under the tray ro add support like is in the superfreak skis. I cut the tray open on my freak when I was going through it so i could inspect the cooling lines. When I sealed it up, I had some 4 inch fiberglass "tape" and cut 4 layers and laid them up. Once cured I cut and fit the straps and riveted them to the bottom side of the tray with some cabosil in between. That gave me a solid shelf to rivet the piece of tray I cut out, then spread thickened epoxy to fill the gaps then laid 4 layers of 8oz cloth on the entire tray to reinforce and seal everything up.

 

[Diametunim]

Alright, it's time to make an executive decision on how to repair this thing. At this point the main thing I'm still debating is whether or not it's worthwhile to cut the tray out and reseal the innards under the tray (cooling lines, driveshaft, exhaust..etc..). I pressure tested the hard-lines (cooling + trim tube) with an air compressor and did not find any leaks. The outside of the exhaust tube is integrated into the composite layup of the hull so I don't believe it's possible to have a leak there. The only thing left to leave concern is the scupper tube and driveshaft tube between the pump. Ultimately I know I should bite the bullet and re-seal regardless, there's not going to be a better time then now. Still, I find myself cringing at the amount of work I know I'm about to undertake.

I'm planning to use my oscillating tool in conjunction with a thin blade or half moon saw blade to make my cuts. The obvious thing is to take as much care as possible when making the cuts in order to not damage anything hiding beneath the tray. my fear is damaging the pump tunnel or midshaft housing making these cuts.

Below is a picture that shows where I'm planning to make my cuts. I'll follow along the edges indicated by the arrows on the blue painters tape. You'll notice that I have "Option #1" and "Option #2" indicated at the back of the tray. I'm not sure which one I should cut along.

Option #1 is forward of the pump tunnel & pump inserts by a fair amount and provides a safety net

Option #2 splits the middle of the two pump inserts. Theoretically, this would allow for more of the tray to be removed and therefore provide more access to the innards.

Below is the underside of the hull for reference.

Would someone smarter than me mind reviewing my homework? I've running out of time to write this post in its entirety. Tomorrow I'll cover the measurements I took in further depth.

 

[Jyzmbe]

Trevor don’t cut the tray out. I recommend sanding the area where the bucket and the tray separated with a piece of folded up 36 grit so you get top and bottom and squirt some thickened epoxy in there (West systems six10 is just easy) and use rivets like mentioned before and do a layup over the tray and bottom of foothold buckets. That will really help strengthen and tie everything in.

As far as prep work goes before laying anything up. Clean everything before hand then go over with wax and grease remover before you sand. You don’t want to work any contaminants into it. Mechanical bond is your friend. I do 36 grit then clean again.

In my opinion worrying about using a resin with UV blockers or something that doesn’t yellow inside the hull is unnecessary. I usually add a little black pigment into my resin. Never see yellow also make sure you squeegee out any bubbles and excess resin.

Looks like those black inserts in your tray are the plastic inserts for foot straps. One set for front and rear already setup regular foot for you like your sj

 

[Diametunim]

Trevor don’t cut the tray out. I recommend sanding the area where the bucket and the tray separated with a piece of folded up 36 grit so you get top and bottom and squirt some thickened epoxy in there (West systems six10 is just easy) and use rivets like mentioned before and do a layup over the tray and bottom of foothold buckets. That will really help strengthen and tie everything in.

As far as prep work goes before laying anything up. Clean everything before hand then go over with wax and grease remover before you sand. You don’t want to work any contaminants into it. Mechanical bond is your friend. I do 36 grit then clean again.

In my opinion worrying about using a resin with UV blockers or something that doesn’t yellow inside the hull is unnecessary. I usually add a little black pigment into my resin. Never see yellow also make sure you squeegee out any bubbles and excess resin.

Looks like those black inserts in your tray are the plastic inserts for foot straps. One set for front and rear already setup regular foot for you like your sj

I thought a lot about what you wrote here and what we discussed over the phone.

I'm sorry buddy, the nagging voice in my head won. Hopefully this is all worth it in the end.

Someone's been here before.