Thursday, August 31, 2017

Armor

Way back in February soon after I started the build I ordered 18 feet of 3/4" x 1/8" 316 stainless steel flat bar from online metals and it's been sitting around the shop until now.  Raw stainless flat bar is reasonably cheap and it should do a good job of protecting the bottom.

The whole process only took a few hours. I started with measuring and cutting the four lengths I needed;  1 for the skeg, 2 for the side pieces surrounding the daggerboard slot and 1 for the keel strip forward.  Next I measured and tapped equidistant #10 holes in each of the pieces.  Finally, I countersunk all the holes so the screws would sit flush.  This is where most of the time was spent. With the drill press at slow speed and periodically adding lubrication while cutting it took quite a bit longer than I expected.  

I bedded the skeg and foward sections with LifeSeal and then screwed them home with epoxy dipped screws.  Before I mounted the strips alongside the daggerboard opening, I cut and fitted some slot gasket material (mylar with dacron scrim backing) and fastened it with 2 strips of wood that I had previously cut, shaped, and painted.

Once that was complete, I bedded and screwed down the stainless pieces and called it a day.  So with that complete, the bottom is officially done.  Of course I still have to build the daggerboard and I guess that will be part of the bottom some times, but I'm not counting it now.






Thursday, August 24, 2017

Hull Fairing and Paint

I took a break from finishing the rudder last week to get the boat flipped over and take care of the hull finish.  I'm not a good judge of weight, but I'd guess the hull is now in the 175 - 225 pound range. The boat is still pretty light but if I keep adding chunks of wood and various pieces it is going to get much harder to turn over, so I decided to get it done now.  My son and I had little difficulty turning it over and I setup some boards on the trailer so the boat could rest upside down on it, allowing me to still wheel it in and out of the shop for the upcoming sanding sessions.

I washed the hull to remove any amine blush on the surface although I've found that the Raka epoxy is fairly low blush.  The hull had a layer of 6 oz cloth and 2 filler coats of epoxy to smooth out the weave, but there was still a bit of a rough weave texture, so once it dried out I sanded the whole thing down with 120 grit on my random orbit sander.

I did a few spot fills of noticeable low spots with TotalBoat TotalFair fairing compound.  I've been using this for a few years on various projects and like working with it.  It uses a 1:1 ratio and one part is colored bright yellow, the other bright blue.  You know that it is all mix well when they turn a uniform green.  I've had trouble in the past with not properly mixing other fairing compounds because both parts are the same color and it's easy to miss fully mixing when you can't see a color change. Other than that it spreads out nicely and works just like any other fairing compound and cures to sand in about 3 hours.

After sanding again, I rolled on a coat of high build one part primer (also TotalBoat) and let it harden up for a day or so.  Now that I had a uniform color on the hull I could really see where filling was needed.  The vast majority was on the hull panels in between the chine tape, although the bottom two panels starting from the keel were in pretty good shape.

After sanding most of the first primer coat off, I mixed up several batches of fairing compound and slathered it on to get rid of the tape lines and waited for it to cure.  Then it was time to sand again, and if you detected a pattern, you'd be right.  Sanding was officially getting old now, but I kept telling myself that the prep is what matters, not the actual painting.  Once sanded, it was again hard to tell where the low spots were because of the mottled color, but I was pretty sure I had gotten most of it.

Another coat of primer, another round of very minor fairing, followed up by a final coat of primer and 220 grit sanding and I was ready for real paint.  When I say ready, I mean good enough for me.  I like a nice finish, but I can only go so far before I call it quits.  Other's may be much more meticulous here, but I know that the boat is going to spend it's life getting rammed up on beaches and rock shelves and trailers and I want to use it, not show it.

For the real paint, I went full stack with TotalBoat products from Jamestown Distributors and chose TotalBoat WetEdge one part polyurethane paint in Kingston Gray.  I've used 2 part paints in the past (Interlux stack), and they do produce a very nice finish, but they are expensive and a bit finicky to use.  I hadn't used TotalBoat polyurethane before, but I've used Brightsides in the past with decent results and I suspect they are probably made in the same factory (TotalBoat is slightly cheaper too).

I mixed up a quart thinned to 10% with their 'special brushing thinner' and went to work with an enamel/urethane 6" foam hot dog roller and did the margins with a good brush where the roller couldn't reach.  The first coat took about 2 days to harden up enough to sand (it has been really humid here in Central NH) and I did the second (and hopefully final) coat last night.  The humidity levels dropped yesterday afternoon and when I closed up the shop for the night I put a heater underneath the boat to speed up dry time.  When I checked on it this morning the shop was a nice warm 85 degrees and the paint was dry to the touch.  From what I can tell so far, I think it looks pretty good.  With the thinner added, it leveled nicely and I don't see any brush or roller marks.  It's not perfect by any means though.  I can vaguely see where the panels are scarfed if you follow the reflection across the bottom of the hull, but there isn't anything I can do about that now.  I'm ready to move on.






Thursday, August 10, 2017

Rudder Time

Despite life being way too busy to fit everything in, I am still hoping to get this boat done before the end of the season, but I'm beginning to think I'm dreaming about getting it done. All the little things are adding up and you can only do them so fast.  Even so, I've spent a few long nights in the shop this week and knocked out the rudder assembly.

The plans call for a swing up rudder accomplished by 2 cheeks that capture the blade on a pivot bolt. It's all hung on the boat with standard pintles and gudgeons that I sourced through Duckworks Boat Building Supply.

For the cheeks, I epoxied together 3 - 6 mm sheets of marine plywood.  I cut them quite a bit larger than the overall dimensions of the cheeks so I would have plenty of room for trimming later on.  Once these cured, I cut them down to the rough dimensions of the assembly and then found a nice piece of cherry to serve as the filler block and cut that to size.  After a few trial fits, I mixed up a batch of epoxy and glued and screwed the cheeks with the cherry filler block together and set them aside to cure.

For the blade, I dug out a 1x6 douglas fir board I had and cut it into 2 - 1120 mm pieces (1097 mm finished length) and then ripped them into 4 - 45 mm strips and 2 - 35 mm strips to get a total glued up width of greater than 244 mm (max design width).  I turned them end for end and then mixed up another batch of epoxy and slathered them up and lightly clamped them together before calling it a night.

The next morning I came back to find everything hardened up nicely and I got right to work whittling the blade down to size.
While I probably should have waited for a full cure to avoid gumming up my thickness planer blades, I went ahead and planed it down from 25 mm to 18 mm.  Fortunately, the planer didn't seem to care and all went well.

I located the final blade dimensions on the freshly planed rudder blank and then cut it out with a combination of the table saw and band saw along with a small helping of the Shinto rasp for the final details.  Now I dug out the tool that all wood should fear.... The belt sander.  I don't use it often because it is not a precise tool, but relies on brute force to make wood disappear.  This is good until you go too far, but I needed to remove a lot of material from the trailing edge for shaping and this can be a good tool for that when used judiciously.

It made quick work of the douglas fir and within 10 minutes I was close to final shape on the trailing edge.  I left a little for some finish work later on, but it's pretty close now.  For the leading edge, I used the low angle block plane, the Shinto rasp and some sandpaper to achieve the bull nose I was looking for.
I finished up the day by tapping the pivot hole for the blade and test mounted it in the cheek assembly.  It was a bit loose, but I will be glassing the blade and the extra width from the cloth should take up any space in the cheeks.

I still have to add about 5 pounds of lead to the blade before I glass it over and I'm currently waiting for some wheel weights I ordered on eBay to show up before do so.  I also plan on mounting a replaceable delrin bushing at the pivot hole so the 5/16" bolt holding it to the cheeks doesn't dig into the blade.

Knowing that I was about to start on the rudder project late last week I found and ordered a set of Racelite RL490 pintles and gudgeons from Duckworks Boat Building Supply in Port Townsend Washington (Racelite RL490).  I've ordered a fair amount of stuff from this place over the years and they have been very reliable and shipping is surprisingly fast even though it is literally on the other side of the country from New Hampshire.
The pintles and gudgeons showed up yesterday afternoon so I got right to work.  I had previously epoxied up a gudgeon cleat blank (as specified in the plans) with one of the batches of epoxy from the rudder blade so I fitted the cleat along with another thinner one that didn't require a multi-piece glue up.  The plans call for the top cleat to stand off 15 mm from transom and the bottom cleat called for 60 mm standoff.  To fit them, I basically held up the rudder cheeks where the corresponding pintles will mount and guessed since the plans don't actually specify where on the transom they should be mounted.  I screwed both cleats right on the vertical centerline with temporary screws, and screwed the gudgeons in place with more temporary screws.

At this  point it was just a matter of lining up the pintles with the gudgeons and marking their location on the rudder cheeks.  More temporary screws and I was ready to test mount.  I could feel the bottom gudgeon binding a bit on the first fitting, so I took the bottom cleat off and ran the face through the table saw at a really shallow angle.  That fixed the binding issue.

So by now, it all fit well, but the cleats were looking pretty ugly, so a few passes on the table saw at a 25 degree angle followed by a 45 degree cut on the ends knocked down the boxy look and then I took the low angle block plane, rasp and sandpaper to soften up all the edges.  I fitted the hardware again to make sure I didn't screw anything up and then epoxied both cleats in place.

I still have lots to do before I can sign off on the rudder project.  First, I have to do some shaping of the rudder cheeks to give a bit of curvyness to them.  I also need to ballast the rudder and add the Norwegian tiller arm as well as permanently mount the pintles and gudgeons, but that will wait until after paint.





















Monday, August 7, 2017

Seat Tops Complete

When I left off last week I had cut out some of the seat top planks but I wasn't entirely sure how I was going to fix them in place.  On the woodenboat forum (here) I had a number of good suggestions with various methods that would not require me screwing them to anything, which would be ideal, but after a number of tries with various temporary fasteners I pretty much gave up and went back to the original plan.

I did learn a new term along the way though, the strips that I intended to epoxy in place to hold the seat tops were called 'cleats'.  So with my new terminology in hand, I got to work.  First I tried cleats that were 18 mm tall, but once I put everything together, it just didn't look right.  I called my wife over to the shop who seems to have a good eye for all things aesthetic and she thought that the cleats were too prominent.  She suggested making them a little less tall.

So I cut them down to 10 mm and both of us felt it looked much better so I went ahead and glued them all down with a thickened batch of epoxy and called it a day.  The next morning before work I coated the newly glued down cleats and all the seat tops with unthickened epoxy.  By the time I got home it was dry enough to test fit the planks and I was happy with the look.

After that, I cut out all the middle planks that will cover the rear hatch and deck and rough fitted them.  I cut the outboard ones a little bit longer than the middle two because my plan was to strike a slight curve on the aft deck planks to make it a little less boxy.

I screwed down the side planks and further refined the aft deck/hatch pieces before taking it all apart again and rounding over all the planks top and bottom with the router.  Once again, I screwed everything back in place for a few final fitting adjustments and then drew an arc on each of the hatch corner pieces to cut out.  I tried a bunch of different curves, but finally decided that part of the curve on the bottom of the 5 gallon bucket laying in the corner was just about right, so I drew it on and took the pieces over to the band saw followed up by a roundover with the router.

So now I have to pull everything apart again (this is getting old) and sand and finish the planks. My plan right now is to use Deks Olje 1 for a matte finish, but I may change my mind on that.  Also, I think it's time for a serious date with some sandpaper and get the interior sanded down for primer.  I still have the removable thwart to do, and a bunch of work forward, but I'm getting close.  I may sand and then flip the boat for final finish work there, but  we'll see.