JEM Watercraft

Started my build last week. Third homebuilt, first JEM Watercraft. Test photograph post from FB.

https://www.facebook.com/photo.php?fbid ... =3&theater

Extended the work table to 16'. Epoxy and fiberglass arrived Tuesday. Tonight I glued the hull panels together. I'll be glad to see it looking like a boat in a few more days.

https://www.facebook.com/sandy.milliken ... nref=story

Things are beginning to move faster. I cleaned up and edge matched the hull panels and got the bottom panels loosely stitched before I called it a day. By this time tomorrow it should actually look like a boat. Matt, you do a great job with the building plans. The suggestion for the jig to drill the stitch holes worked like a charm.

https://www.facebook.com/sandy.milliken ... 532&type=3

Got it stitched together today. I really like the lines of the Cape Fear. Now that I can see its shape, I can hardly wait to get her finished.

https://www.facebook.com/sandy.milliken ... nref=story

So sorry everyone. I thought I had set my album on FB for public viewing, but Al Gore's amazing internet got the better of me. Here are the pictures in photobucket:
http://s300.photobucket.com/user/Sandy_ ... t=3&page=1 Please let me know if you have trouble seeing them.

Ah, that's better! It's looking good Sandy - keep up the good work.

Thanks, Bob. How do you like your Laker? I had a tough time deciding, settled on the Cape Fear partly because that's near my home town in NC. And I like the looks of it.

Okay, I'm thinking ahead about setting up for storage and have some experimenting to do. I want to use the narrow fore and aft sections for flotation. But I don't want to buy an access hatch. I saw an ad for some Gore-Tex vents for surboards and paddleboards- has anyone tried making their own breathable vents? I'm going to try gluing a piece of Tyvek in a sandwich of ply with about a 1" hole, and using that as a breathable but watertight vent for the floatation chambers. Is Tyvek okay or should I use Gore-Tex? or should I have an access hatch?

I am no engineer by any means, but my untrained, inexperienced intuition says to me that breathable and water-tight cannot co-exist.
Are air molecules all that much smaller than water molecules, that you can keep out water and let air pass through? Maybe so, I don't know.

If you're just only concerned about blocking spray or the occasional wave, and don't care whether it gets somewhat damp inside for a while, I guess breathable would be okay, but if you're aiming for totally dry, I doubt breathable would do it.

LesForgue wrote:I am no engineer by any means, but my untrained, inexperienced intuition says to me that breathable and water-tight cannot co-exist.
Are air molecules all that much smaller than water molecules, that you can keep out water and let air pass through? Maybe so, I don't know.

If you're just only concerned about blocking spray or the occasional wave, and don't care whether it gets somewhat damp inside for a while, I guess breathable would be okay, but if you're aiming for totally dry, I doubt breathable would do it.

Thanks Les The main idea is to take advantage of the technical fabrics to let air pressure equalize in the "sealed" flotation chamber. They let air and water vapor through but keep liquid water out. The downside is not having physical access inside the compartment.