Spindrift 10N #1621 Build Log

[Bryan Rolfe]

One other thing I'll share is that I discovered you can iron peel-ply with no consequences -- at least as long as you don't over do it and turn the steam off your iron. A lot of the peel ply I've bought online has shipped folded, and then you get pronounced crease lines in the fabric that absolutely will show up in the resin, somewhat defeating the purpose of peel ply in this application (e.g. to reduce sanding time). 

Since I learned this, my results with peel ply have come out worlds better.

[Paul356]

Your work looks great.  I'm especially impressed by the long, smooth whitish fillets.  Good tip on peel-ply, too.

[Bryan Rolfe]

Got the trunk box situation fixed. I had to switch it to the starboard side, which also meant, because I had already glued on the spacer pieces to the stbd piece of plywood, that I had to cut and laminate new port piece so that I could properly match the hull shape. 

 

I decided to approach the trunk installation a little different than the manual, because I think it will be easier to trim the top of the trunk flush as needed once installed plumb and straight, than trying to iteratively go back and forth with my block plane. So instead of assembling the trunk completely, I kept one side open. I then fit this to the nesting bulkheads and hull the best I could, using a long piece of straight plywood, a machinist square, and a digital level to make sure the one half of the trunk was aligned to the boat axis, and plumb relative to the gunwales at the center of the boat. Only after that did I clamp on the other half of the trunk box to "close it" and ensure everything fit correctly.

 

 

 

Then, I tack welded in the starboard side of the trunk so that I could remove most of the clamps/braces. After that cured, I drilled a hole through the hull inside of the trunk box, taking a lot of the guess work out of cutting the slot later. Now I can just use my router and flush trim out the slot. 

 

 

I then glued on the port half of the box with some thickened epoxy. 

 

 

And clamped it all up and clamped on a piece of hardwood at the front of the box that is clamped to the gunwales, this was to correct a slight tilt out of plumb at the front of the trunk box (since the tack welding really only makes the back, where it's welded to the nesting bulkheads, plumb). I had to use one screw through a piece of plywood to apply clamping force on the nesting bulkhead side of the box.

 

 

 

Once that was cured, I went around and added fillets, glass tape, and peel ply to complete the job. 

 

 

Peel ply on over the glass tape:

 

Peel ply removed:

 

I complete most of the glueing of the trunk assembly today, and then flip the boat over tomorrow probably to cut the slut and add the keel.

[Bryan Rolfe]

Got the slot cut, which was pretty easy with a flush trim router bit. Only difficulting was on the side where the box is angled, as the angle prevents the flush trim bit from cutting all the way to the edge, so I had to file/sand that side down the rest of the way. Gaps were filled with thicken epoxy.

 

Also glued on the keel -- I used a lot of ratchet straps to achieve the required bend.

 

I also applied a light fill coat of epoxy to one side of the boat to  try and smooth out the surface -- it was peel plied, but there were defects that I wanted to correct to make for a nicer finish. Unfortunately this coat didn't go on very well, as my cleaning was not completely adequate, possibly residue from the acetone or lacquer thinner I used. Now I have started to use a scoth-brite type pad with RO water as my last step before coating with epoxy (in addition to cleaning with a solvent and removing all dust), and following up with a tack cloth. If the water beads up at all, then it's not clean enough. 

 

After sanding this semi-failed coat down, I decided to add epoxy fairing compound to all outer surfaces, and have got about 2/3rds of the boat sanded fair. Might go back and hit a few spots again. This has greatly improved the surface smoothness, but I think I would have been happy either way in the end. In the photo below, the transom has not yet been sanded. 

 

 

I also decided to add 2 extra "strakes" or mini keels on either side of the hull. I couldn't really find photos of anyone else doing this, but I'm sure someone has. The reason I added these is because the boat will be our primary tender, and hauled out on shores of various conditions. It probably wouldn't take very long for the paint to get scratched up. These additional keels are tall enough to prevent any part of the hull from touching the grand when hauled out onto a relatively flat surface. 

 

The only thing I stupidly didn't think about is how this will affect the nesting. There's only about 1' protruding into the forward half of the boat, and the keel height is only 0.62", but it might be enough to interfere. Guess we'll find out! 

 

I also don't know how this is going to affect sailing performance, but honestly, I think I'll be able to live with it. 

 

 

 

 

[Aphers]

I added bilge strakes, or runners if you prefer. Three good reasons:

- they stiffen up the floor

- they protect the hull from damage

- they gave me a solid place to add through bolted eyes for lifting the dinghy in davits

 

Mine are on the aft half only so don't interfere with nesting.

 

I'm not the only person to have done this, Sailing Florence of YouTube fame did the same.

 

https://messing-about.com/forums/topic/12813-spindrift-11n-build-in-scotland/page/2/#comment-111096

[Aphers]

.

[Bryan Rolfe]

Great to hear! I thought I remembered seeing them on Matt and Amy's dinghy, I think that's actually what gave me the idea. 

if they end up interfering with the nesting, I can plane/sand them off pretty easily.

[Bryan Rolfe]

Got the bushings completed on the mast sections. will probably sand down the front of the bushings a bit more to provide a smoother transition between segments, since I plan the sail to be laced to the mast, and I don't want it to get caught on these transitions when lowering.

 

 

 

 

After sanding:

 

 

[Captain Tim]

This is the way Peter McCrary did the top of his mast. As he points out it makes nesting the mast sections doable. I copied his idea and it works well. Here are a couple of photos.

 

This pulley arrangement is an alternative to a cheek block at the head of the smallest mast section — which would  prevent “nesting” of that section into the middle section of the mast assembly. 

[Bryan Rolfe]

That's a great idea and definitely one I'm going to adopt. The smaller we can pack away the mast, the better. 

[Bryan Rolfe]

Work has progressed slowly the last two weeks owing largely to strong storms here in California that also knocked our power out for 3 days and projects on the big boat.

That said, the hull has been faired (two passes with fairing epoxy fairing compound and lots of sanding). After the first pass and the 2nd application of compound, but before the second sanding:

 

You can also see in this photo that I wrapped the rubrail around the stern. 

Once the boat was flipped again, I spent a lot of time sanding down the edges of all the tape as well as other places that were not very smooth. This was honestly a lot of work. Most of my fillets are pretty good, but the last ones I did on the trunk were superb in comparison. I recommend anyone doing glass fillets for the first time to practice a few and nail down a good technique. It will save a lot of sanding and back-filling later.

 

I also fitted the wooden pieces that support the middle thwart. Here I am just using weights to hold things in position as the epoxy cures for the supports:

Tonight I got 2 coats of epoxy on, and will put a 3rd on tomorrow. I'm using a slow-cure epoxy for this, and temps are low, so I should be well within the tacky window tomorrow still. I'm using a roller, which works ok. My epoxy (and probably all epoxies) seems to be really sensitive to any sort of surface contamination. Despite what I thought was a rigorous cleaning, I still have places where the epoxy wanted to bead up. It's possible I sanded blush into the surface, but I thought I cleaned all my epoxy surfaces before I began sanding. 

 

I still need to fit the mast step, and re-enforcement at the bow for the tow line. I also need to finish shaping the rub rai and add coats of epoxy to these as well as a few other bits. Then I'll probably go back around the boat and add a bit of thickened epoxy where it's needed to correct any imperfections.  

Next week and weekend I'm travelling for work, but hopefully I can have paint on the boat before the end of the month. 

 

[Lille Ø]

5 hours ago, Bryan Rolfe said:

That said, the hull has been faired (two passes with fairing epoxy fairing compound and lots of sanding). After the first pass and the 2nd application of compound, but before the second sanding:

That’s looking great! I wish we had the time for a couple of more rounds of fairing. Oh well, whenever the boat needs a repaint…

[Bryan Rolfe]

Sometimes I wish I was on a tight schedule so I'd have an excuse to stop fairing!

 

Got the boat outside to more easily clean off the amine blush, as well as fit the mast step (can't get the first mast section to fit inside the garage).

 

It was actually pretty satisfying to hear water sloshing around inside the dinghy for the first time. Made me excited for when we get it out there for the first time. 

 

Mast step epoxied in place:

 

Back in the garage I spent a solid day sanding. I've really about had it with the Total Boat epoxy for coating work. It does say that it's not designed for finish work, but it's hard to decipher for what reason exactly. In my experience though, it has a tendency to bead up more easily, and doesn't self-level as well. 

 

Here's an example of the sorts of imperfections I'm still left at in places after sanding. I didn't want to sand them completely out yet since I think I'll burn through the adjacent areas in the process. 

 

I decided to do another coat of epoxy. Partially because I sanded so much of the other ones off, but mostly because I wanted to reduce the imperfections as much as possible before switching to fairing compound, if that's what I decide to do.

 

Luckily, I have some Resin Research epoxy from a few surfboards I built. This stuff is designed for finish coats and you can add a bit of xylene (they call it Additive F) to it to improve it's self-leveling qualities (at least I think that's what it does). I figured I might as well give it a shot. 

 

I think the result came out a lot better already, though it hasn't yet cured. 

 

 

I think maybe one problem I was having with the total boat epoxy is my own fault though. I was using a tack-cloth as my final prep step, and I think this is a mistake. I think some of the wax in the tack cloth contaminates the surface. I should have followed the tack cloth with an acetone wipe down. 

[Don Silsbe]

I’ e started using a dry microfiber cloth as a tack rag. It sucks up a lot of dust.

[Steve W]

Brian, I built an 11N about 11 or 12 years ago. Your build is bringing back a lot of memories, so thank you. 

 

Also, I noticed my link to pictures of my build was not correct so I just updated it for future posts. Here is the link: https://photos.google.com/share/AF1QipMlU_1VC8tTkcQQrtwHpU0YSOjUznp0Kz2C0tbHR0uaWbor3cClQKHbcb_cIcCbGw?key=Q3JhMGRjeHpOMjFOakR6VnNpbXd0bVFxTHUyVGNR

[AmosSwogger]

Interesting observations concerning the epoxy beading up; I've never seen or heaed of that (I've only used B&B epoxy).  Thanks for letting us know.

[Bryan Rolfe]

I am now in the phase of the build that really seems to be the slowest. I haven't had a lot of time to work on the dinghy, in the last few weeks, but when I have, a lot of my time has been spent sanding and fairing. I think I'm letting perfect be the enemy of progress now though, and honestly, this will be a working utility dinghy for us, it's not going to be a show boat. 

 

In any case, here's where things are as of today. 

 

I've added the bow-eye reinforcement, and drilled the hole for the painter. It is very slightly off-center, but that's ok. I used a block of cherry cut to fit the bow, epoxied it in place, and added 6 layers of glass tape tapering outward. I'll need to come back here later and add some thickened epoxy to clean up the tape lines/etc. 

 

 

For the rest of the interior, I spent a few days sanding everything thoroughly, and went around inspecting for defects. After a lot of consideration, I decided to use fairing compound to correct some of these. Again -- they wouldn't have been noticeable at any reasonable distance, but I couldn't help myself. 

 

 

 

 

Afterward I added one last coat of epoxy over everything. I think this is 3-4 coats in total, depending on the location, but I sanded pretty aggressively in the fairing process. I'm hoping this finish coat will only require an amount of sanding purely necessary to provide the mechanical adhesion for the paint. 

 

 

 

 

 

I also got most of the rigging hardware. 

 

This week I plan to paint if time/conditions allow. I should at least be able to get the primer on. Once the interior is painted, I'll separate the two halves and flip the boat over. I need to do a quick repair on one of the nesting bulkheads, and apply some epoxy to the strakes and keel, but otherwise the hull is ready for paint too. 

[Bryan Rolfe]

Ah, the day is finally here. Painting has begun! 

 

I'm using Epifanes 2-part polyurethane paint and primer. So far I've only put 1 to 2 coats of primer down -- a few places still need their second coat. 

 

The first coat I did on the aft side I did not have brush thinner for, and as such, it went down very thick and was not at all easy to apply, especially in corners. I also was using a nap brush rather than a foam brush. After this coat cured, I sanded it pretty good with 220 grit to flatten out any drips etc. But for the fwd end and subsequent coats, I am not sanding, as long as I re-coat within 24-48 hours. 

 

The fwd end and subsequent coats I used a foam roller and 10% Epifanes brushing thinner. Those were a piece of cake, and for the detail areas I used a synthetic brush. For the hull corners though, I actually just pressed the roller into the corners after I had laid out most of the paint from the roller. That worked very well. 

 

For those wondering about quantities, I used 1 x 750ml can of primer (2 parts) and that got me almost 2 coats. I think it might have gotten me 2 coats if I had used brush thinner the first time around. 

 

 

 

It's honestly not totally clear if I needed the primer. Epifanes says a primer should be used on epoxy, but I also know people directly paint their epoxy boats with paint. 

 

I'm waiting on a fresh order of paint and primer, but I think I will get into actual painting this weekend. Then I will need to flip the boat. 

[Bryan Rolfe]

After finishing the primer coats, I found some defects/pin holes that I wanted to address so I went back with fairing compound in a few places. 

 

I should have followed up with a primer coat in these areas, not so much for paint adhesion, but to reduce the number of paint coats I'd need to obscure the green fairing compound. But, I was out of primer, and my order for more primer and paint just got delayed a week. 

 

 

 

In any case, I moved on to painting with the 2-part Epifanes Polyurethane. I also only have one 750ml can of this as I'm waiting on the same delayed shipment. It seems like 1 can gets me about 2 - 2.5 coats. It's really unfortunate that the paint is delayed, as I was assuming I'd be able to apply the 3rd and maybe 4th final coats without having to sand -- since the recoat window is 48 hours. 

 

I'll try to see if I can obtain the paint locally, but it's not looking good. 

 

But hey, the boat is starting to really look professional now!

 

[Aphers]

Looks great! It's such a huge transformation.

 

I painted my boat with it in two halves, hanging from overhead beams. This let me access almost every part of the boat in one go, instead of having to do it in stages.

 

My paint supplier said I didn't need primer. I only actually did two coats initially, but I generally add a full coat once a year now that the boat is in daily use, plus patch repairs where necessary.