Infuse Strip-Planked Kayak Using MTI hose?

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#1

I’m seeking feedback. I am gearing up to infuse carbon fiber to the interior of a strip-planked kayak. I’ve typically done this with a hand layup but I want to improve on it.

The mahogany strips are 1/8" thick. To provide some structure I plan to apply a light layer of fiberglass to the exterior using a hand layup. This may not be 100% airtight so I intend to put the whole thing in a bag.

Because the CF is going directly against the wood, not a smooth mold I assume the flow of resin may be uneven. To reduce the risk of issues I am thinking of using MTI hose all the way around the upper perimeter.

I don’t have any flange so I’m thinking of temporarily taping some 1/8" thick plastic sheet along the top edge. This will provide a foundation for organizing the hose.

I would introduce the resin from a EnkaFusion line down the full length of the keel.

Attached is an illustration of my thoughts for the setup, plus what the intended final result should look like.

This would be my first effort at infusion. There is a lot of labor getting the boat to the point of doing this infusion. I don’t want to wreck all that work.

What are my risk factors and potential pitfalls?

#2

Guillemot
I think your plan will work.
Start by doing a flat test panel that is the same distance from the enkafusion to the edge of your double bag. The panel only needs to be a foot or 2 wide. set it up exactly as you intend to do the real deal. This will tell you if you will have any issues and will give you a good idea how long the infusion will take.
Ensuring you are using resin, peel ply and bag that is intended for infusion, will help avoid disappointment.

You build really nice boats.
Martin

#3

I wonder what will keep your epoxy from penetrating the wood. Besides that I suggest putting perforated plastic on top of your peel ply under the mesh to ease in mesh removal.

#4

I suspect the epoxy will penetrate into the wood some. The grain of the wood does absorb some resin even in a hand layup.

Also note that the strips are hand fitted together with a rolling bevel made with a block plane. As a result there may be some gaps between some of the strips. I’m assuming the resin will flow into these gaps and fill them up.

Since these gaps run the length of the boat, they will primarily be perpendicular to the flow of the resin, so I don’t expect detrimental race tracking.

Thanks for the suggestion of the perforated release film. I was worried about pulling out the flow media/peel ply. The film would let me break it down into easier steps.

I will have to do some sanding of the interior prior to applying a clear coat finish. I usually brush on an epoxy “fill coat” on my hand layups. I’m thinking of laying a layer of 2oz or lighter fiberglass to protect against sanding into the carbon.

I’ll be making some test panels first. I’ve not done any infusion before and my last experiment with vacuum bagging was about 20 years ago.

#5

Yes, release film is something you’d wish for when you’re removing the vacuum bed :wink:

Looks good, but with thin laminates like this the extra work and materials are inefficiënt. But usefull when you have to do a lot on your own, or demand a high quality laminate!

#6

I keep waffling on this project because it would be easiest to just go ahead with my standard hand layup, but I’m hoping to get a quality improvement.