Using the correct product (primer) this time, I painted the inside of the aft hull section.  The paint was quick to flash off once applied, which led to many lap marks as I struggled to work my way logically through the whole section, which process was admittedly more of a challenge than I’d expected (and I’d expected a challenge).  However, I got coverage everywhere, which was the goal, and since the boat would be sanded before any further work, the lap marks didn’t matter at this stage and frankly couldn’t be avoided despite all efforts.

I painted the face of the forward bulkhead, and also the transom, since these areas would be primed later anyway, and it made sense to do them now.

I continued the varnish buildup on the tiller and extension with coat #2, an offshoot of my varnish work on another project.

In the afternoon, I saw a good opportunity to apply primer to the interiors of the boat halves.  For this job, I chose Epifanes 2-part polyurethane and appropriate primer for both inside the hull (white) and the outside of the hull (a custom mix to match the owner’s sailboat).  While I’d used, and liked, other Epifanes coatings over the years, I’d not ever used the 2-part specifically.

Earlier in the day, I’d pulled a package containing the paint for the job from a storage area where I’d been keeping it warm, and after confirming the label through the packaging (because I’d ordered both primer and topcoat), pulled out one of the two cans of primer inside the plastic wrapping and set it aside to use now.

I mixed the paint as required and set to work on the forward half, which was the “easier” of the two parts.  For primer, I figured I could cut in and tip with foam brushes, since at the moment I didn’t have any good brushes on hand other than the ones I used for one-part paints, but I didn’t want to start with a used brush.  Immediately, I was surprised at the nature of the primer and, since I chose to start with cutting in the difficult parts of the boat–the underside of the breasthook, and the corners at the aft end beneath the bulkhead gussets and such–I was quickly lamenting the lack of a good brush, but the product was covering fairly well (not as easily as I’d expected), and eventually I coated the whole section satisfactorily.  I was thinking the primer was surprisingly glossy and more finicky to work with than I expected, but overall the coating came out pretty well, and after all, it was just primer.  The small rectangular piece shown is the daggerboard slot cover.

I’d started with a fairly small batch, and while it had been more than enough for the forward half, I could see I’d need more for the second half.  Somewhere around here–I don’t know how exactly  it came into my conscious, it just did all of a sudden–I got a bad feeling, and felt the pangs of Captain Obvious, sometimes abbreviated as “DUH”; I rushed to check my paint can.

Did you see it coming?  It turned out that I’d mixed and used the topcoat for “primer” instead of the primer.  It seems I’d ordered one can of each (I ordered it a while back), and both cans, which looked similar enough to be roughly identical at a glance, had been wrapped in the same overwrap for shipping.  While I’d confirmed the primer label earlier in the day, the can I actually took out was the topcoat.  I was focused on the back of the can, where the mixing instructions were printed, and, being new to the paint, it never was obvious during mixing that I was using the gloss topcoat, especially when I knew I’d read the label through the packaging earlier in the day.  The cans happen to be identical except for the specific product labeling, which one might have thought was enough, but for the specific circumstances and a certain level of brain-deadness.

Doth I protest too much?  Maybe, because I’m embarrassed, but it was also easy to do even in hindsight, particularly when I thought I’d ordered two cans of primer which, naturally, would be packaged together.  Sigh.

Quick:  Which is which?

There’s no shame in mistakes, only in pretending they don’t ever happen.  I share this because it happened, and I could have easily chosen not to share it.

At this point, I cut my losses and left the aft half for another day.   This was a stupid, but not unrecoverable, error, and I planned to treat the first coat of gloss on the forward half just as I would if it was primer.  The good news in all this was that I learned some valuable things about the topcoat application, which would serve me well when I started to actually use the product intentionally later on.

If I’d had enough of the first mix left to complete the aft half, I might have just gone ahead with it despite the error, but since I didn’t have enough already mixed, I saw no reason to push forward.  That said, it’s notable that the designers of the boat write in the manual that “they don’t believe in primer” and the instructions don’t call for priming the boat before painting, even though I chose to stick with my own process and experiences and intended to use primer all along, and which I still think is the correct practice for any coating.

I might have mixed primer and done the aft half correctly, but the primer mix required a mix ratio based on weight, not volume (how annoying, by the way), and I had no means of weighing it at the moment.  It seemed better in all ways to stop and regroup, and turn to the aft half on another day.

No hours were harmed during the making of this mistake.

 

While my main focus remained now on another project at the shop, I still worked on the dinghy most days to continue various epoxy and related steps that were close to being, but not yet, done.

On Monday, I applied a second coat of epoxy to the rudder case, after sanding lightly the first coat, and with the same batch of epoxy applied another coat inside the holes bored for the rowlocks.

On Tuesday, I continued the process on the rudder case, with a third and final coat of epoxy on all sides.

I unmasked the rowlocks, now that the epoxy work was complete there.

At the aft seat, I bunged the screw holes from installation, installing the bungs in thickened epoxy to ensure that the screw holes were filled and watertight, since the installation screws had necessarily penetrated the aft buoyancy tanks.

With this work complete, on Wednesday I could get to some of the final preparations required for primer, mainly cleanup and masking.  I pared away the excess bungs from the aft seat cleats (sorry, forgot to photograph this), and, after cleaning the inside of the boat thoroughly, masked over the various new installations on the aft hull:  aft cleats, foot cleats, and rowlock risers, along with the connecting hardware.  On the forward hull, I masked the connecting hardware and the inside of the mast tube.

Since I had varnish underway for another project at the shop, it was a good opportunity to start the process on the tiller and tiller extension.

To give me better access to the inside of the hulls for painting, I dismantled the 4×8 plywood build table I’d constructed atop one of my normal shop benches, as this work table addition had increased the height by 4″ and made things awkward for reaching inside.  With the boat essentially complete, I no longer had need for the big table, and with it dismantled, I could set one half on the now-lower-and-narrower table, and the other half on a pair of sawhorses of similar height.  Now I was ready for primer whenever I had a time window.

 

It seemed a good day to finish up some of the last details required before moving on to primer and paint.  I started with the aft seat cleats, which I’d already epoxy-coated and varnished.  To install the cleats, I masked off a portion of the aft tanks, and taped the plywood seat in place so I could roughly determine the fore and aft position of the cleats.  The cleats were longer than the seat was wide, and were designed to extend beyond the seat by a bit on both sides.  By eye, I determined the placement and made a mark on one side, which I duplicated on the other.  This gave me the forward end of the cleats; then, I marked a line 7/8″ down from the top of the aft tanks, which represented the top edge of the cleats. From there, I dry-installed the cleats with two screws each, which screws would also hold the cleats later when gluing in place.

Note that in these photos, I had the boat propped vertically with the transom on the floor, which gave me the best access for this work.

With the cleats thus installed, I cut around them with a knife and, after removing the cleats, pulled the tape from the footprints.  Then, I installed the cleats permanently in thickened epoxy in the usual way, pulling the masking tape once I’d cleaned up the squeezeout.

Next, I unclamped the rudder case and spent some time sanding it clean and smooth.  I block sanded flush the ends where the 18mm plywood spacer met the edges, and rounded over and sanded smooth the edges of the plywood, with a small roundover hand-sanded on the inside edges of the plywood as well.  I built a simple plywood support stick that friction-fit inside the case, leaving all edges and sides accessible at once for epoxy-coating, the first coat of which I applied now.  I clamped the stick to the bench to let the epoxy cure all over.  There’d be a couple additional coats of epoxy over the next several days.

For the rowlocks, my next step was to drill through the gunwales for the 5/8″ bore required for the rowlocks themselves; the wooden risers had this 5/8″ hole already installed, which acted as a guide to drill through the gunwales.  I clamped a sacrificial board beneath each location so the drill wouldn’t break out and damage the underside of the gunwales.  I dry-fitted the rowlock bases to make sure the flanges fit flat against the riser; on one location I ran the drill bit through again to slightly open up the bottom part of the hole and allow the barrel of the rowlock base to fit properly and allow the flange to sit flush.

Those would get permanently installed later, but now I masked off around the holes and treated the new bores with epoxy, using a small brush to coat the insides of the holes.  I’d do at least one more coat later before calling this complete.

Now that the epoxy had cured overnight, I removed the rest of the masking from the rowlock risers.

Next, I turned to the rudder case.  Before disassembling the dry-fitted parts, I noted the reason why it was unimportant that the fiberglass sheathing on the insides of the side panels didn’t have to extend to the tips:  the area was completely contained within the area covered by the internal plywood spacer.

I disassembled the clamped-up parts and pulled the alignment nails, leaving their tips just poking out through the plywood to aid in aligning the center spacer.  Then, I applied epoxy gluing mix to the spacer and installed it on one of the cheeks (facing up on the bench), then applied glue to the other side and installed the second panel, tapping in all the alignment nails, ensuring the parts were visually and by touch, and then clamped the pieces securely.

I didn’t overdo it with the epoxy, using enough without too much of a surfeit, and now I cleaned up the narrow interior of the assembly with a dry brush to remove the minimal epoxy that had squeezed out on the inside; the way the assembly worked, the interior had to remain clean and clear for the rudder to fit and operate properly.  I checked carefully with a strong light shone into the space to ensure it was clear.  At the top of the case, where the tiller would eventually go, I smoothed the excess squeeze out into a small fillet on each side.

I left the rudder case securely clamped to cure overnight or longer.

To begin, I finished removing the masking tape from the new foot cleats.

Next, I worked on the layout and preparation to install the rowlock risers.  These were centered 2″ and 22″ on each side aft of the bulkhead in the after hull section, and at these points I installed two layers of masking tape to cover the gunwales, and marked at the appropriate measurement using a straight ruler as shown in the book.  Then, I marked a line in 13/16″ from the gunwale edge to center the risers longitudinally.

I masked off the risers, and, with each one in turn clamped in place properly aligned with its two centering marks, used a knife to cut the gunwale masking tape along the outline of the riser.

I epoxied the risers in place with the usual thickened mixture–no clamps required.  I carefully cleaned up the squeezeout from around each riser and let them be to partially cure.

Several hours later, the risers had cured enough that I could remove the tape from the gunwales, but I wouldn’t remove the tape from the risers themselves till the epoxy had fully cured overnight.

I dry-assembled the rudder case parts so I could drive alignment nails (for use during final glue-up) and check the fit of the now-completed rudder in the assembly.  First, I clamped the two plywood halves together and drilled the 1/4″ through-holes at the two locations (one for mounting the rudder, the other for the tiller).  Then I inserted the rudder in the space–it fit with only a slight friction, which I felt was correct–and, with a drill bit inserted through the hinge pin hole, checked its general orientation and operation, all of which seemed good.  The tiller as is fit nicely in the upper section of the rudder case, which meant that now I could go ahead and varnish the tiller to complete it.

I was tempted after the dry fit to go ahead and glue up the three parts of the rudder case, but it promised to be a fairly fussy process and, as I’d used up my self-allotted time for the day, I didn’t want to feel rushed through the process (there’d be a bit of fiddly glue cleanup inside the case itself), so I left the final assembly for next time.

While there were still small jobs to do, I allowed myself an hour or two first thing in the morning to accomplish what I could before shifting focus to my other ongoing project.  To begin, I flipped the foils over and applied a gloss coat of epoxy to the second side, same as the first.

Next, I worked on the rowing foot braces.  The kit came with a paper template to locate the braces, which I used quickly to locate four large patches of masking tape on each side, then replaced the template so I could accurately mark the locations with little marks at the four corners of each slot.  I repeated this process on both sides of the boat.  I held each of the eight braces in place and cut around the base with a knife, so that I could remove the tape from the footprint.  I labeled each foot brace and location accordingly.

I masked each brace completely for protection, then installed them in a thickened epoxy mixture, cleaning up the excess glue but leaving all the tape in place for the moment.

After a few hours, I carefully removed the tape from the hull, but left the tape in place on the braces themselves as I didn’t want to jar the still-curing epoxy.  I left the braces to cure overnight, and would remove the remaining tape in the morning.

 

Now that both sides of the foils were fill coated and cured, I could trim the excess fiberglass from the second side, and finalize the sanding and shaping of both pieces.  I sanded the glossy epoxy flat and smooth with a sanding block and finessed the edges by hand (especially the leading edge) to achieve the final shape.

Before continuing, I checked the daggerboard to ensure it fit in the slot.  There was as yet nothing to hold it in place, so I had to hold it while doing the check, but the board fit through both ends of the slot with no issued whatever.

Now, I applied a final gloss coat of epoxy to the first side; I’d do the second side on a different day.

I lightly sanded the outboard mounting area to smooth the epoxy fill coat and complete the construction work there.

The rudder and daggerboard required some preparation before I could install the fiberglass on the second side.  To begin, I used a knife trimmed the excess cloth from the first side.

The leading edge required some sanding and shaping to finalize the profile and bevel and slightly round the epoxy bead I’d installed from the first side.  This wasn’t difficult and didn’t take long, but one could see how it might easily be done incorrectly, as the job required a certain sense of what the shape should be and how to create it.  I masked the plywood to help gauge where the sanding was occurring, and used a small sanding block to bevel and shape the epoxy leading edge, sweetening it by hand thereafter.  Around the remainder of both foils, I lightly sanded flush the remnants after I’d cut away the excess cloth, and sanded the top edge of the cloth where it wrapped onto the plywood edges at the 18mm thick top sections of each foil.

I sheathed the second side of the foils the same way as the first, with one layer of 4 oz. cloth and, on the daggerboard, a second layer at the top, which extended an inch or two down onto the hydrofoil.  The cloth wrapped over the edges of the full-thickness portion of each foil, extending well past the seam from the first side.  As before, I let the excess cloth on the leading edge side drape well past the curve to help the fiberglass cling to the newly-shaped area as required.

In other works, I trimmed and lightly sanded the sheathing I’d installed over the outboard modification at the transom, and then fill-coated the area to fill the weave of the cloth, essentially finishing up the work on this area.

The bulk of the small parts now had enough varnish for installation, but the top, visible side of the aft seat still required a few sprayed coats, which I finished up during the day.

Later in the day, when the fiberglass on the foils had had about 5 hours’ cure time, I returned to apply the epoxy fill coat to both parts, rolling on a thick coat of epoxy to fill the weave of the cloth and prepare the second side for eventual sanding and final fairing.

Starting first thing, and throughout the morning, I applied a few more coats of varnish to the small parts using a small sprayer; this time around, I flipped the seat blank so the final exposed side was now facing up to get some varnish, as the underside was sufficiently coated for now.

Fifth coat (first on seat blank):

Sixth coat (second on seat blank):

Seventh coat (third on seat blank):

The next step for the daggerboard and rudder was to inject a bead of epoxy into the little void along the leading edges of both foils.  The shape of the leading edge, and the way the fiberglass draped over the edge (with no attempts made to wrap it beneath the rounded edge) left an small open space that was visible with the foils turned over onto their recently-glassed sides.

With a syringe, I injected a bead of thickened epoxy mixture into this void, including along the tips of the foils.  This bead filled the small space till it was flush with the top edge of the curved leading edge.  I lightly smoothed the bead with a finger to avoid leaving too much epoxy, as I’d have to sand and shape this area later, before installing fiberglass on the second side.

With the foils turned back over to the working side (glass side up), the purpose of the filling was made more clear.

Next, I rolled on a nice fill coat on the new fiberglass, heavily enough that there’d be no problem to sand and fair the foils smooth when all was said and done.

I trimmed the overhanging fiberglass from the rudder case spacer piece, and sanded flush the four filled holes in the two case sides (one hole leaked out around the tape at the bottom, so I added some extra filler now).  Then, I installed a layer of 4-oz fiberglass over each plywood panel; the fiberglass as cut to the prescribed size didn’t cover the lowest parts of the case, and the book made it clear it was not necessary.  I also installed a 2″ wide strip of 4 oz. cloth over the curvy edge of the spacer; this wrapped under and onto the straight edge by under an inch on each end..

I sanded flush the newly-glued plywood outboard mounting reinforcement, and cleaned up the fillets and around the part as needed to bring things to a more finished appearance.

Next, I installed a layer of 4 oz. fiberglass over the vertical face, which replicated a similar piece I’d installed on the original inwale and would also help toughen and reinforce the outboard mounting area.  With leftover epoxy, which I turned into a fairing mix, I cleaned up the fillets a bit to improve appearance.  I let the fiberglass run over the various edges for later trimming.

Most of the remaining parts of the boat were now in play and under some form of construction or finishing at this point, and there was literally nothing left to do while waiting for fiberglass or epoxy to cure, or varnish to dry.   I planned to come in on the weekend to continue the varnish buildup as necessary, and to glass and coat the second side of the daggerboard and rudder, but there was no further project advancement possible at the moment–and I looked through both manuals for anything at all that I might be able to do right now.

I’d enjoyed being able to dedicate full-time to the building of this dinghy till now, without too many forced early departures, but the construction was now at a stage where there simply wasn’t enough left to do in order to justify full shop days’ attention.  Plus, other scheduled projects in the shop loomed ahead and needed to get started, so this would be the last week dedicated entirely to the dinghy.  From here on out, I’d divide my time between this and other projects as needed in order to finish the boat.  This is a rough list of what remains to be done, construction-wise, vaguely in order of operation:

1. Install rowing foot cleats and rowlock risers
2. Final work on the outboard modification
3. Finish glasswork and prep on the daggerboard and rudder, and associated parts
4. Interior prep, primer, and paint
5. Exterior prep, primer, and paint
6. Rubrail
7. Final details like rudder hardware, fitting the aft seat and daggerboard slot cover, protective pads for nesting, and fitting the forward hatch