Poulsbo Pram Construction Continues

[Jim Cav]

Yup - you sanded through the epoxy coats and down to raw wood. You don't need to coat the entire boat
again though, just the places you did too much sanding. The important thing is to avoid sanding through
the veneer. Once that happens you'll have a blemish that can't be fixed by anything but a coat of paint.

And no need to be embarassed, sanding through the epoxy happens to most everyone, myself included...in
MANY places on my PMD.

Jim

[drpaddle]

Thanks (again), Jim. Clearly, next time I'm in Mass. -- hey, it could happen -- I'll have to buy you the beverage of your choice. In the meantime, now I know what to do (the garage space heater is once again engaged ...). Seriously, thanks!

[drpaddle]

Hmmmm, yet another dumb question. Will I touch up the overly-sanded spots with a foam brush or roller? What I mean is, would the foam brush work? It's cheaper than a half-roller ....

Maybe I'll try a spot and see what happens.

[Jim Cav]

As you've probably already figured out, a foam brush will work fine for small areas. I wouldn't want to do too large an area with one though...that
would take forever and use a lot of epoxy.

And did someone say beer?

[drpaddle]

I have figured out that I won't gain weight during boat building, even if I eat the wrong stuff and don't exercise -- because I will worry away all excess calories.

I stitched together all the hull panels and they seem okay. But I plopped the transoms up there, thinking I could stitch them on this weekend, and, well, it seems like the notches in the transoms, which ideally would match up with the edges of the strakes, uh, don't.

This is because, especially at the ends, the strakes aren't pulled in tight. As in:



and



See what I mean? These gaps really don't want to close up. I might be able to get 'em tighter if I pull my wife out of her deathbed -- well, she really just has a bad cold, but still -- but they're tough.

But, unless I get 'em tight, it seems like the transoms won't match up very well with all those strake-ends. As in:



and



So, sure, I've read that getting the transoms on require a certain amount of foul language. I'm up to it. But ... should I step back and find a way to pull those strakes in tight first?

[Jim Cav]

If it REALLY REALLY bothers you...you can add a few more stitches to help reduce the gap along the strakes, but for the most part you
will never see any of the gaps between the strakes and transoms again. Well, you do on the outside a bit, but it's barely visible and any
gaps are filled with epoxy.
The fillets cover over most all joinery in these boats. As you'll find when you install the front seat, there are places where you just won't be able to get
a tight fit, and that's okay. All of the strength in this construction comes from the epoxy, and trust me...it is STRONG stuff!

So get the strakes and transom "close enough", but don't hurt yourself stressing about it. It'll come out looking great.

[drpaddle]

I ended up adding a couple of stitches at each end to pull the strakes together more tightly, to give me a comfort level with stitching on the transoms. The result? The transoms went on pretty easily -- I was able to do it on my own, which is just as well because wife Susan still has a nasty cold and wasn't too jazzed about helping.

Pulling the strakes together so I could add the stitches required more than two hands, though, so I employed bar clamps -- one small one on each of two adjacent strakes, then a slightly larger one pulling the two small clamps together. Yeah, Rube Goldberg, etc., but it worked (probably better than using a spouse).



I'm reasonably pleased with how the transoms have gone on -- the largest gaps are in the bow transom:




... the widest of these gaps comes in at less than 1/8". I think it will work fine. Not much overhang with the strakes -- just enough. I may not even need to use the saw much when the time comes -- I may be able to just sand off the ends. We'll see.

You can see below that there appears to be a bit of twist in the hull (of course the bulkheads are just propped in there for the moment). Not much of a twist, but it's there, depending on how it's sitting on the sawhorses, and could have me sailing circles around my friends without meaning to.

Applying quite a light torque straightens it ... and I'll have to figure out the correct way to ensure it IS straight before I get much epoxy into the boat. Adjust stitch tension? Glue a heavy fishing weight onto the port side? Hire a college kid to lean on the port side? I dunno yet. But it seems doable, somehow.

[Jim Cav]

Looks good!

Don't worry about any twists just yet. You worry about that when you're gluing the bulkheads in. It's easy to get the twist out, just shim under
the hull where it rests on the saw horse. Even then you'll still twist a bit as you move things around. It's the seats that REALLY tighten things up.

Jim

[drpaddle]

I got the transoms tacked Sunday afternoon -- my first experience with wood flour and the peanut-butter variety of epoxy. Fascinating! Also the the first time I've noticed epoxy warming up as I worked with it. This could have something to do with it being in my hand (in a freezer bag) for a bit as I tried to fill up the seams, but still it seemed nice and warm. It's curing up nicely in my 62-degree garage -- I have to give it 48 hours because I'm too cheap to heat the garage to 75.

I made 2/3 of the recommended amount and still had a bit left when I finished -- I'm going to have to start making up just half the recommended amount going forward.

My first fillets go on this evening (if I ever meet all my work deadlines today). I've read everything I can find on fillets, so it's just a matter of executing. I'm sure I'll get it at least 37% right.

[Jim Cav]

The thickened epoxy can get hot in larger amounts. I made up a batch once that was WAY to big, and as it sat in the plastic bag it got downright hot!
Small batches are certainly the way to go. This stuff is too expensive to toss into the trash.

Take your time with the fillets. Make sure you have time to be able to monitor the hardening. You really really really really need to be there when the
epoxy gets firm enough to allow for the smoothing with the denatured alcohol soaked (and gloved) finger. If you don't smooth them out at this point,
you're looking at significant sanding later. You can only imagine how many hours it takes to fix substandard fillets. I don't have to imagine.....unfortunately..

[drpaddle]

Last night I got the the transom fillets on. As with most tasks in the build, I learned stuff and should improve my results on future fillets. Maybe.

This masking job looks okay, but afterward I think I should have not masked quite this tightly. I needed to allow for a wider bead touching the wood.


You can see how far the bead -- and I use the term loosely -- extends onto the tape. Yes, I cleaned up this bead some, but there was still a bit of a 'raised edge' on the bead when I removed the tape.


After a couple of hours, I pulled the tape and smoothed everything. The edges of the fillets ended up not being as straight as I'd like, but I could have done much worse. Next time I'll remove the tape right after beading and tooling, and clean up the edges with a plastic squeegie (or something).


The stern transom came out neater, overall -- easier to do, I think because the more acute angle with the hull meant a narrower fillet. But here you can see -- darn it -- one of the little ridges left when I removed the tape, and which I somehow managed to ignore last night while smoothing. So here will be a bit of sanding to smooth this out. I can live with it though.


Next up: stitching in the bulkheads. The sense of progress is highly rewarding.

[drpaddle]

Last night I got the stern transom stitched on. Measuring and re-measuring and pondering and related activities accounted for 98% of the time I spent.

Following the manual's instructions, I measured along the bottom panel, out from the transom, and also measured one the diagonal from the top of panel #4 at the bow. The manual says the bulkhead, placed thusly, will be approximately plumb with the floor if the boat is level--which, of course, begs the question "what's level?" With all the rocker the PMD has, and without the ability to float it in some water to see where it settle, it's kind-of hard to tell.

I decided to use the diagram in the manual as a means to determine level. Who knows if I got it right? It's sort-of close, surely. But, having done all that ... no, the bulkhead didn't seem particularly plumb.

So I temporarily abandoned all that and grabbed the stern thwart, using it to fit things together and see where the bulkhead needed to be. At the end of the day, the cut-outs in the thwart MUST straddle that bulkhead, right? So I went with that approach. Of course, the resulting location wasn't very much different from what I had determined by measuring. But it was different.

I attribute this difference to ... any number of things. There's room enough, in all the different instructions, for variance (such as how much the strakes extend beyond the transoms at this stage -- mine, very little).

So, it seems okay, with one issue: though I was able to pull the panels in pretty darn close to the bulkhead, the sides of the bulkhead extend maybe 1/4" - 1/3" ABOVE the gunwale (or what passes for a gunwale now). I can find no evidence of anyone else having this issue. I seems like it will be easy enough to sand the bulkhead down a bit at the ends ... but, darn it, how come everything doesn't come out perfectly? This is far too much like real life.

I plopped the seat back in just to see how things fit -- it's sagging a bit at the stern here because I couldn't find anything, at the moment, to prop it up.

[oldboater]

I had that trouble with the rear seat, it kept tipping down away from where it's supposed to be. I marked the correct position on the transom and glued some scrap hardwood blocks to stop this 'tipping' and act as a support under the seat. These worked out great as the rear seat became more stable and made the final filetting easier.
Alan

[Jim Cav]

Same here. I glued a "tripler"...1 more than a doulber...to the lower part of the transom to 1) support the back of the seat and 2) to give the
screws from the rudder hardware something more to dig into.
And I also had bulkheads that extended up past the sides. These are simple to sand down to the proper height later on.

[GORP]

The "ears" of my bulkheads also protruded - about the same as yours. Just don't be an idiot like me - a happily start sanding them off - not realize that they nicked the sandpaper, and gouge out a hole in the pad on the sander.

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