The whole point of this site is to share not just the joys of the project, but the sobering moments as well. Here, I will summarize some of the lessons learned, as I go along:

1) Planking selection: The decision to use 1/4" bead-and-cove planking on a 15' catboat is still questionable... I'll have to wait and see how it turns out. However, it is already clear that there are advantages and disadvantages. The reasons I decided to go this route are a) I didn't want to have to rip the strip planking myself, since it's tedious, and my table saw is a cheapie, b) the cost of Eastern White Cedar strips from Classic Boat Kits looked fairly competitive to what it might have cost me to rip my own strips, and c) I figured that 1/4" with two layers of outside glass, and one layer inside, would be adequate, considering the permanent frames.

I thought that the bead-and-cove would be a big advantage, in terms of helping to lock the strips together and give me a smooth result. However, it actually might have been a disadvantage. The 'cove' side of the strip is fragile, and I often broke the edges during handling. Furthermore, since the hull is going to be fully glassed and faired, I could have easily used square-edged strips and have still gotten the same result.

In retrospect, I might have been better off to rip my own strips, and used a 1/2" thickness, so there would have been enough 'meat' to edge-nail or dowel the strips together... this would have eliminated the 'valleys' where adjacent strips twisted somewhat to give me low spots. As to whether the thickness is adequate, I'm encouraged by what I see so far (12/30/03).

Update on thickness: at this point (3/16/04), I think the 1/4" planking is just fine... the exterior/interior glass adds tremndous strength, and the framing and deckbeams will add even more.

2) Stapling: Speaking of bead-and-cove strips, it is important, when stapling, to bias the staple towards the 'cove' side of the joint, not the bead. Too many of the joints weren't fully seated because the staple caught the 'cove' too close to the edge, and didn't hold the strips together well enough.

3) Checking fairness of the setup: The biggest mistake so far: not spending more time with test battens to prove the fairness of the frame setup before planking. The problems at the 'B' frame resulting in a gawdawful bulge which required drastic measures to fix, and the repair isn't pretty... luckily, it's all below the waterline.

4) Height of the setup: The strongback could have been a bit higher; the sheer dips fairly close to the floor, making sanding down there difficult.

5) Sanding disks: I've always used sanding disks for my Bosch random orbital sander which are red in color, and have a closed-coat surface; I was able to buy these cheaply at Woodworker's Warehouse for about $12 for a 50 disk package. Since Woodworker's Warehouse has gone bankrupt, I was forced to buy my disks at Lowes, in a box of 25, for $9. Much to my surprise, the new disks, made by Norton Abrasives, are far superior. They are yellow in color, are 'open coat' (i.e., there are spaces between the individual grit grains), and don't load up nearly as much as the red resin-coated disks. They seem to last just about as long, as well. They're not quite as heavy, and rip a bit more easily if I happen to catch an edge... but, on the overall, they're much better.

6) Dust Control: I have always been far to cavalier about the issue of dust control. Back when I built a few smaller boats, I simply resigned myself to the fact that the garage would load up with sanding dust, and I only sporadically used a cheap paper dust mask... very foolish. When I started this project, I did the same. Soon, the garage was filled with white sanding dust, and the cold I had gotten around New Years didn't seem to be going away; I was still very 'phlegmy' when I coughed. Finally, it occurred to me that I might have gotten sensitized to the epoxy. I went out and bought a top quality respirator, one which would be comfortable to wear and do a really good job of keeping the dust out of my lungs... it cost $40, but was worth it. I also decided to hook up the shop vac to the exhaust port of the Bosch sander. It's cumbersome because of the hose, and rather loud with both the sander and vac operating, but the net result was barely any dust being generated. I'm extremely sorry that I didn't do it this way from the beginning.

7) Recycling sanding dust: In the course of cleaning out my shop vac, it occurred to me that I might recycle the dust generated from the sanding process as a filler. The Microlight 410 I've been using is wonderful stuff, but it's very expensive, and it seemed to me that I could supplement it with what I could reclaim from the shop vac. I scooped out a container's worth of the sanding dust, picked through it to remove the obvious contaminants (specs of glass cloth, minor wood chips, etc.) and used some of it to make up a pot of epoxy for a final fairing of one of the low spots. It turned out to be a BIG mistake; the resulting mess was VERY hard to sand, and there was a LOT of crap in the compound that had escaped detection, including some staples which the vac must have sucked up from the floor. Perhaps the dust could be recycled after careful sifting, but I think I'll stick to virgin materials from now on... it wasn't worth it.

8) Notching the frames for inwales: I had decided, when first setting up, to not attach the inwales to the frames before planking, reasoning that it would be a simple matter to notch the frames after the hull was turned. I didn't want to mount the inwales to the frames before planking, because I was afraid that the stiffer inwales (3/4 x 1 1/2 fir) wouldn't lie fair to the same curvature as the planking. In retrospect, this was a mistake, because cutting those notches afterwards was something of a pain to do, and not a neat job. What I probably should have done was to pre-notch the frames, start the planking below the notch, and add the two final strips to the planking after the inwales were mounted. It's not a big deal, just a minor annoyance.

9) The cradle design: I didn't think very hard, at the outset, about being able to reach into the hull to do the interior 'fitting out'. The cradle I built, albeit simple, wasn't designed to allow a good 'reach' into the hull (it's too high), and certainly won't support my weight if I try to climb into the boat. I'm probably going to have to modify/rebuild it, at some point, to be able to get inside safely, especially when I need to fit the coaming.

10) Using the wrong bit: I have a number of drill bits with countersink collars, but most of them do not have the correct 3/8" countersink to mate with my 3/8" plug cutter, for using bungs. When I went to assemble the centerboard case, I had only #8 screws... but only a #6 tapered bit with 3/8" countersink. I've gotten away with this mismatch in the past... but only in softer wood. In oak, it doesn't work too well. I snapped a couple of screws (necessitating the use of a screw extractor), and also broke a couple of phillips driver bits. The lesson: use the correct tapered drill and countersink to match the screw size!

11) Underestimating material needs: Twice now, I've gone to the local fine hardwoods dealer, to pick up white oak, ash, etc., and bought less than my needs. It's not that big a deal, since Downs & Reader is just around the corner from my office, but it's wasteful of time, and since the milling charge (for surfacing both sides and ripping one edge) is a flat $25, it's wasteful, as well. From now on, I need to estimate more carefully and buy enough to meet the needs, plus a little extra (I'll probably use it eventually, anyhow).

12) Measurement error: When I used the laser to establish the level for the floors, I made a mistake. The boat wasn't perfectly level athwartships. Part of the fault lies in my crummy cradle design, which is a bit rickety... I should have spent more time in building better bedlogs on the cradle. Regardless, I can see now that he cockpit floor is tilted a little bit. functionally, it won't matter, but from the perspective of appearance, it might be visually obvious after the deck and coamings are completed. Fortunately, a 'fix' won't be to bad; I can shim the edges of the floors so that the floorboards are level. It will be tedious, but possibly necessary. The lesson learned: check and recheck your measurements before making an important installation.

13) Deckbeam slope: I took some care in scribing the crown on the deckbeams, using the trick described in both Wooden Boat, as well as the West System Boat Construction book. However, the net result isn't quite what I wanted. When building the deckbeams, I decided to scribe and cut the crown before mounting each beam, because it might have been difficult to do it after mounting. That judgment turned out to be correct... but I should have left a generous margin on the deckbeams before mounting, in order to have enough 'meat' to level them with a plane after mounting. Without sufficient margin, I lost a bit of the crown in the process of leveling... not enough to want to rip them all out, but still... another lesson learned.

14) Clamping the tiller lamination: The raw laminated blank for the tiller came out pretty good... but not perfect. During the process of tightening the clamps, I could see that there was a bit of a gap between the uppermost mahogany strip, and the ash strip beneath it, right at the peak of the arc. I tightened up near there to close the gap... but as I tightened elsewhere, I could see the gap return. I did the best I could, and when the lamination cured and I planed away the squeeze-out, I could see that the gap was still there.... very small, and filled with cured epoxy, but there, nonetheless.

After thinking about it, I think I know the reason why. I should have tightened the clamps from one end, progressively, instead of trying to tighten down all the clamps evenly. What probably happened is that there was a bit of a bulge in the top strip, and due to the fact that clamps on both ends were tight, the top strip couldn't slide laterally to take out the bulge. If I had tightened progressively from one end, the top strip would probably have conformed better to the stack, because the loose part would have been free to move laterally as I tightened. It's no big deal (I'm certain no one else will notice it)... but I know it's there.

15) Springback on the curved carlins: this error is discussed on the page named 'Deck Framing Continued'. I think this failure was a compound mistake, consisting of several parts: #1, making the form itself just 90 degrees, without any margin, #2 insufficient clamping at the ends, and #3, letting the lamination cure in the cold, rather than bringing it into the house to cure at room temperature. A good object lesson in not thinking things through clearly, which will require me to re-saw some more ash strips, and build a whole new form. The old form can still be used for bending the coaming, though.

16) Clamping screws and washer for teak strips: I used the common method of driving screws with washers in between the strips to serve as clamps for bonding the strips down to the sub-deck, as well as to space the strips evenly. The idea of using hex-head self drilling screws as a very good one; they were easy to drive and exerted a lot of clamping pressure. However, I used ordinary #8 and #10 washers, which were too small; the result is that there are some depressions of the teak strips near where some of the screws were driven. I should have gotten larger washers, possibly plastic ones, to minimize or eliminate this problem. As a result, I'll have to sand the deck somewhat aggressively to get rid of these depressions.

17) Bending plywood: Before building the coaming, I tested whether the 1/4" marine fir plywood would bend to conform to the 24" radius of the curved portion of the cockpit, using a scrap left over from the subdeck. It seemed to, but when I finally got around to building the real thing, I broke two of them. I'm not really sure why the test piece seemed to make the curve, but perhaps it was because it was narrower than the final coaming. In any event, since the coaming was going to have two layers of 1/4" ply, I recalled the trick of sawing a series of shallow kerfs to enable plywood to bend more easily... and it worked beautifully. I should have thought of that before wasting a sheet of plywood.

18) Masking: Before coating the outer surfaces of the coaming with epoxy, I laid out a plastic film sheet and taped it carefully along the deck, so as to avoid epoxy drips on the decking. However, I left this masking tape in place as the epoxy cured. This was a big mistake: the epoxy migrated a bit beneath the tape, bonding some of it to the deck. It would have been far better, and a lot neater, to have removed the masking after coating. Therefore, my new rule is to NEVER leave masking tape in place after coating anything... always remove it, even if it means re-taping for successive coats.

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