Brian.

I have built 4 MC 13's. The First by kit the rest on my own.  If you have glassed the bottom and have enough glass to glass the deck in one piece, I would do it.  It will save you from trying to smoth out the seam in the deck if done in two piece's.  Also I don't think it makes any difference on the drection of the glas weave. 

My kit had enough to do the botton in one piece, the deck two.

Its a great boat I think you will like it.

Lance

If you can do it in once piece, it will be fine and easier than dealing with a seam.  I don't believe that orientaiton will be a problem - I've always done the deck fiberglass in one piece and at a bit of an angle on my boats.  I think that being on the bias (at an angle) is actually a bit easier because the cloth has more give to fit around curves in that direction instead of straight on.  (I just put the fiberglass on the deck of my Wood Duck this morning, all in one piece and on a slight angle; waiting for it to cure a bit more before trimming the overlap onto the hull and then the fill coats).

Thank you both for the responses. I will go with the one piece versus two. I am looking forward to finally being able to paddle it.

Brian

Not only will be easier not dealing with a seam, as both respondents have already said, it also makes the boat stronger to have long unbroken threads in the deck cloth. There's more tensile strength on the outer layer of the deck that way.

Laszlo - Okoumefest survivor

Disagree about the "stronger boat" claim. First, this is cloth (woven, not stitched) we're talking about. The fibers already zigzag in each direction due to the geometry of the weave. Second, the light cloth used on a kayak isn't strong enough to make a global difference- it barely changes the panel stiffness. Rail to rail is generally the smaller dimension of the boat's panels, and the relavant distance to be studied. So with zigzagging small fibers, a pretty small splice (overlap) will transfer 100% of the loads.

How far does the damage extend beyond the dent in any of the puncture tests you've seen? The cloth rarely shows damage more than an inch away in pics I've seen...

But eliminating a seam is a good thing for smoothness.

Nemo,

The threads don't zig-zag, they fold over and under each other. It's quite possible to get a continuous mostly straight thread for the entire length or width of the boat. Yes, the folding caused by the weave has less tensile strength than if the threads were laid over each other as in bi-directional cloth.

Puncture-resistance is different from, though related to, tensile strength of the external layer. I was talking about tensile strength.

You are right, depending on the weight of the cloth there's probably no practical difference. But I must say that 6 oz cloth perceptibly stiffens 3 mm wood, especially if one waits for the full cure.

And I'm in total agreement with you and everyone else who says that a seam is a good thing to avoid.

Laszlo

I cam see that having no seam would be quite a bit less work, but I actually have four layers of glass on the keel of a 10 foot skiff that I built. There are two layers of tape (narrow & wide) and then the bottom was covered in two overlapping pieces. Finally, there are two two coats of graphite and epoxy.

I can understand the desire to keep the weight down in a kayak, and for strength, a single layer would be strong enough, but my rational was that if it was going to be dragged on sand or shell beaches, having more epoxy and glass on the keel would be a good thing.

Of course, after re-reading your original post Brian, it is the deck you are getting ready to glass! Go for the one piece solution!

Keith (13 days on the water so far!)