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stripperguy 02-09-2017 01:11 PM

Oh those!!
They go in the back of my Element haven't had them in the vehicle for the last 4 or 5 years
Each one is over two times my target weight for the canoe!

stripperguy 02-23-2017 08:47 PM's been a while.
Since my last post I've:

1. Added to that pile of window air conditioners that sneak into the photos
2. Ordered and received 4 inch wide bias woven carbon fiber tape for the gunnels
3. Found my roll of 9 oz, 4 inch wide fiberglass tape for the gunnels
4. Ordered a 4 ft x 8 ft sheet of 1/8 inch thick Divinycell for bottom stiffening
5. Spent a week and a half in Florida while missing the best powder skiing in two years.
6. Washed away all traces of the PVA release film from the inside of the shell

Today's record warmth was just the ticket to drag the shell outside and scrub away the stuck on PVA release film. I was trying to use a rag and bucket, and that just wasn't doing the job. So I dug out a garden hose, turned on my outside water line, and scrubbed and rinsed until the inside was ready for some stiffening foam, resin and a little more cloth.

While I had the shell outside, I took the opportunity to snap a few photos, in the basement (or boat shop ) I can't get far enough away to gain the proper perspective.

Here's the shell, with sporadic patches of PVA still stuck inside, and the ready for epoxying foam gunnels sitting on the wavy sheer line.

But here is another view, better showing the warts and all...I should be able to smoothly profile the foam gunnels before applying the carbon and glass tapes.

Here's the business side, which is all that I care about. In fact, other than a Dynel wear patch and some paint, the outside is as done as it's gonna get!!
I'll worry about aesthetics on the next boat.

Zach 02-24-2017 01:47 PM

It's looking great, thanks for the update. The outside of the bottom looks very well shaped, you must be pleased with how well it matched the plug.

Cold River Bob 02-24-2017 05:45 PM

When you took the carbon copy off the plug how did the plug clean up?
My other question is wouldn't the seat stiffen up the bottom like in the Blackjack?
I'm thinking about trying it on one of of my canoes either the 14 ft or 12ft, want to see how yours turns out.

stripperguy 02-24-2017 08:09 PM


Originally Posted by Zach (Post 256346)
It's looking great, thanks for the update. The outside of the bottom looks very well shaped, you must be pleased with how well it matched the plug.

I am very pleased with how well the shell followed the plug..but those "if only's" haunt me.


Originally Posted by Cold River Bob (Post 256349)
When you took the carbon copy off the plug how did the plug clean up?
My other question is wouldn't the seat stiffen up the bottom like in the Blackjack?
I'm thinking about trying it on one of of my canoes either the 14 ft or 12ft, want to see how yours turns out.

The plug (my red Kite) looks terrible!! But it's mostly adhered release film, sloughing chunks like some kind of leper. There must be spots where the paint is missing, but once I wash the boat down, it shouldn't be too bad. It doesn't take too much red paint that stuck to the inside of the shell to really stand out.
I bought a big (4 x 8) sheet of 1/8" thick Divinycell foam, same stuff that many commercial builders use. I'll cut a big football shaped piece to epoxy in the bottom. Then I'll use a bunch of excess carbon to laminate the foam, finally covered by a single layer of 6 oz glass. As it is now, the bottom sections are pretty flexible. The bilge, crease, stems are incredibly stiff.

I plan to make a pair of seat supports similar to the red Kite, maybe a little smaller in section. The supports couldn't stiffen enough of the bottom by themselves.

Oh sure, let me be the canary in the coal mine!! ;);)
Actually, I held off until I watched another couple guys (on another canoe forum) do their composite builds. Any of your boats would be a great plug for a composite shell.

In retrospect, the Kite was about the worst first composite build I could have chosen. The radical crease and the existing gunnels presented the biggest challenges. A more conventionally shaped hull would be a cake walk, or so I say sitting behind the keyboard!

Cold River Bob 02-24-2017 08:18 PM

Thanks Mike You pretty much ans. all my questions. I been following it on the canoe forum you sent me the link . I;m thinking more about my 14 ft doing it.

stripperguy 02-24-2017 11:33 PM


Originally Posted by Cold River Bob (Post 256352)
Thanks Mike You pretty much ans. all my questions. I been following it on the canoe forum you sent me the link . I;m thinking more about my 14 ft doing it.

The clincher for me was the cost of the carbon fiber being equal to the cost of the wood. Add that to the substantially lower work effort, it was a no brainer!

Go for it, I say.

Cold River Bob 02-25-2017 09:03 AM

I'm going to get stuff around an that will be next winter project . You'll have it at the camp out in May Ill see it then if we decide to go

timberghost 02-27-2017 11:19 AM

The "business" (waterline) side of the hull looks to be perfect. The gunnels are tough on the kite. Maybe a strip of wood clamped to the gunnels could help or might cause more problems with creasing...

As an arm chair observer, here's a 'stupid' question (of laziness variety):
With all the mess and fuss of PVA, do you think wrapping the plug in boat shrink wrap (the thick blue heat shrink material they use on powerboats) could work? It probably won't be quite as nice and smooth on the inside of the composite hull and gunnels would be a problem on this boat, but would the polyethylene film release from the new hull resin? (it would probably have to be peeled back after the plug is out as it would not stick to the plug at all)

stripperguy 02-27-2017 07:58 PM

Mr ghost,
I frequent "another" forum that has grown to have a large group of us builders.
One of the fellows uses window shrink film. He has had his challenges with it, particularly with a hull that has much tumblehome. Not sure how that film would handle the crease.

The PVA was actually quite easy to work with, water soluble, so removing the residue was too simple.

As I mentioned upthread, those "if only's" haunt me.
If only I had forced the shear to more closely follow the plug, everything would have been peachy.
Even now, I can conceal my poor workmanship with the shaped in place gunnels, but it sure would have been nice to make up the gunnels off of the hull. So it goes...

On the plus side, I received the 4 x 8 sheet of 1/8" thick Divinycell today. So I guess it's time to quit goofing off!

stripperguy 03-01-2017 10:45 PM

The 1/8" thick Divinycell arrived yesterday. It was rolled for shipping, pretty dramatic unleashing! Here's a look at the left over chunk. BTW, it feels about as hard as cedar.

I laid the foam into the bottom of the shell, and penciled in a trim line a little ways above the bilge. I trimmed the foam with a utility knife, and marked the location of the foam in the shell with a red Sharpie so I reposition the foam in the same spot. And also so I could apply just enough epoxy.
The foam was a bit stiff. I played around with the heat gun to thermoform it, but that was taking a lifetime. I also filled many zip lock sandwich bags with water, to use as a conformal ballast. Every bag leaked, so that was out too. So, due to excess excitement and a shortage of forethought, I decided to wing it!

I mixed 12 oz of epoxy and added Cabosil to give it some body. I poured the thickened epoxy directly into the shell, and spread it out with a squeegee.
Here's a look at the partially spread out epoxy, you should be able to see my red traced line, and the poured in epoxy.

From there it was a simple matter to place the foam back in the shell, lining it up as it was before. And....wait for it....yup, I paid the price for my haste!
While the Divinycell laid in the shell nicely, it didn't fully conform to all of the contours. For the next 30 minutes, I was scrambling around, looking for every piece of compliant (and not so compliant) ballast that I could find. Window casing, baseboard, short 2 x 4's, paint cans, 6 ft level, bags of grout, bags of plaster, more paint cans, yup, I even have a bag of Weed n Feed in there...It wasn't pretty.
But, I think I have all of the foam intimately in contact with the shell.

Here's a look at my near disaster

Once the epoxy is firmed up, I'll add a layer of carbon and a layer of glass.
And that should stiffen the bottom adequately. The rest of the shell has enough curves and creases to provide plenty of stiffness. The stems are particularly rugged.

JohnnyVirgil 03-02-2017 08:07 AM

I'm soooo curious what the final weight will be!

stripperguy 03-02-2017 09:42 AM


Originally Posted by JohnnyVirgil (Post 256478)
I'm soooo curious what the final weight will be!

Uhmmm, me too!!
Just weighed it this morning.
19.5 lbs so far!!

Zach 03-02-2017 09:47 AM

That's a lot of ballast. I would have been worried about that much weight deflecting the outer skin too, but it looks like it worked for you. I know when I buy foam chair cushion material it comes rolled up and I'm supposed to wait a few days for it to resume its untrammeled shape, but I don't know if that applies to Divinycell or not, or if it would have helped since the bottom is not really flat anyway. It looks nice from here.

stripperguy 03-05-2017 04:22 PM

Sad, sad news...

I used my scrap pieces of carbon cloth yesterday to laminate the inside of the Divinycell foam stiffener.
And when I say scraps, I mean scraps. The smallest pieces were about 4 x 6 inches, although most of it was the off cut excess that tapered from 10 inches to a few inches for a length of 5 or 6 feet. It looks kind of patchy, and I'm sure I paid the price in extra weight for my refusal to buy more carbon cloth. So I had plenty of spots that ended up with double overlaps (that's 3 layers) and of course extra resin to saturate all those joints.

I do not like this particular weave of carbon, way too stiff and it takes forever to wet out. I am not satisfied with the quality of my wet out, I have a handful of small bulges.

Anyway, I checked on the shell a few minutes ago.

It is stiff!

I do wish I had performed some load-deflections tests on the shell before adding the foam, and after adding the foam and compare to now, with the single layer of carbon fiber. I dare say I could likely walk in the shell with a good bit of it unsupported. Very much like my stiffest wood strip hulls.

Now for the truly disappointing news. Weight so far = 22.5 lbs. And I still have gunnels, thwarts, seat pedestal and seat to add.

Based on how stiff (relatively) the shell feels and the resin saturated carbon binge, I think I'll will only add a small bit of glass, nearest the seat pedestal.

I apologize for the lack of photos, I'll post some later tonight after the added glass is in.

This has been a baptism by fire for me...lots of lessons learned.
The next boat (you knew there would be a next boat) will nothing like my last boat.
I will use a more supple and compliant weave of carbon cloth.
I will build a glass/carbon/foam/carbon/glass laminate.
I will build in a set of female forms, starting with the foam and working in, then wrap the outside after freeing the shell from the forms.

As promised, a few photos of the patch work carbon. The flash makes the patches more prominent than in person. Do I care? Not in the least, this is a practice boat!

Zach 03-08-2017 07:28 PM

I'm sorry to hear about the weight, that must be a bit frustrating. The use of scraps is a sign of thrift, in my opinion, and therefore nothing to regret. I did a similar thing with the fiberglass on the inside of my second canoe but it doesn't show as much, being fiberglass. I had bought enough cloth to make two Wee Lassie IIs and instead the second boat was over a foot longer, so I had at least a dozen pieces, including some long triangles, as I recall.

stripperguy 03-08-2017 08:36 PM

I consider this a practice build, the lessons learned are far more valuable than the boat created in the process.
I did add a few more patches yet, to cover some of the spots where the carbon shifted as I was butchering the wet out.
On the bright side, however, this is one of the stiffest hulls I've built, and I see the path to a much improved version.

Take a look at the photo below, I have my full weight (no camera tricks) in the hull, with the hull supported in the cradle. Roughly 8 feet between supports. There is maybe 1/16" deflection when I apply my massive 155 lb, fully dressed load. Remember, there are no gunnels and no thwarts, just the bare hull.

Fisheater 03-12-2017 11:44 PM

The strength is impressive! Would you consider using carbon fiber rather than glass for a strip build? I can't wait to see how you do the tractor seat also.
I hope you penciled in a day off this week, big snow is coming your way. In MI the weather lady is predicting 3"- 5", it has been such a poor winter I may take one of the vacation days I have been hoarding to ski. I have all sorts of deadlines, but it seems like there is always a deadline. The little kid in me could really use a snow day.

stripperguy 03-28-2017 07:10 PM

Wow, it's been like 2 weeks since I updated this...
MDB and I put food on the table with our rental properties, getting two units ready at once for April 1 occupancy kind of slows me down!

I cut the Divinycell foam gunnels to be 3/4" x 3/4", with a narrow slit 1/2" deep to fit over the sheer. I used Allen's cut the corner off a baggie trick to fill that narrow slit with Cabosil thickened epoxy. I gotta say, it's a great technique.
Epoxied the gunnels in place with a healthy overhang at each stem.
Then I sanded the foam gunnels to true up the profiles and allow an easy transition for the bias woven carbon fiber tape. Really just a bevel.

I used that cool flex board to sand that bevel. I carefully placed the hook and loop 40 grit paper slightly offset, so there was no danger of digging into the hull as I sanded. In the photo below, see how the paper is offset to the left?

Well, despite my precautions, I somehow got the flex board flipped around for a time. The result in the photo below.

Yup, sanded clean through!! No big deal, that area will have carbon fiber wrapped on the foam and both inside and outside of the shell.
So maybe tomorrow, I'll clean up all the clingy residue and wet out the gunnel wrap.
I have a trip scheduled for the end of April. Depending on how many casualties we have, we may have an odd man out. That odd man would be me, so I have to stop fiddling around and get this thing ready to float.

Zach 04-02-2017 12:18 PM

It looks like lots of progress being made. I sanded through the wood in a couple of spots on my last canoe, but that's life. I'm sure yours will turn out well. Can you take your red Kite if the new one's not ready in time? I'll be very interested to see how the gunwales turn out.

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