Spindrift 10N #1621 Build Log

[Bryan Rolfe]

After a lot of deliberation, we decided we are going to build a Spidnrift 10N as our tender for our Westsail 32. We have big plans for our Westsail, so this boat will be our primary means of transport for groceries, hauling supplies, snorkeling, diving, etc. I had a 27-foot boat prior to our current boat, and cruised with an inflatable dinghy. We went back and forth for a long time on whether or not it would be practical to have a hard dinghy, but in the end I think we've made the right choice. I'm especially excited to be able to sail around anchorages and in our home port here in Monterey Bay. 

 

Currently though, I work way too much, and decided that if there's any chance of this project being finished in a timely manner, that a kit was the right approach. I don't know exactly how many hours we're saving not having to source marine plywood, transport it, loft patterns, and cut the pieces, but I suspect it's a decent chunk. I am lucky that I get to work from home, so I will probably be spending about 2 hours a day on the boat during the work week, and likely one full weekend day a week. I may also take a week off work just to push the project through when it's at a stage where that time can really be spent (rather than time waiting for epoxy to cure). 

I have no experience with stitch and glue, but I did build a hollow wooden surfboard a few years ago, and have plenty of additional experience with epoxy from my big-boat projects, so fingers crossed all goes well! 

 

[PadrePoint]

Nice. You’ll have good success. 
I helped my neighbor (9th grade girl) build her Spindrift 10.

If you hit some snags or questions, people are quite free on the forum to offer experience and solutions. 
Be sure to spend time on Alan’s CS15 video series for all KINDS of detail and help in building.  
2nd video on this page:

https://bandbyachtdesigns.com/cs15
 

[Bryan Rolfe]

Went down a rabbit hole and watched all of Alan's videos on that build, that was super helpful!

 

I started the build this week:

• Glued the side and bottom panels together (finger joints)
• Glued the re-enforcements on the bulkheads and transom
• Glued the panels together to create the "butterfly"

Mistakes I made:

• Did not adequately wet out the first finger joint and there are some gaps on the underside I'll need to fill in later
• Glued up the wrong bottom pieces to one another (such that the CNC-ed lines are not on the same side). Not a big deal, but means I got to transfer some lines

 

I used peel-ply throughout so far, mostly to experiment with using peel ply, but also it has made things a lot easier and has helped ensure things are wet out (when done correctly) and help reduce the amount of sanding.

 

 

[PadrePoint]

On 9/3/2023 at 10:54 PM, Bryan Rolfe said:

Glued up the wrong bottom pieces to one another (such that the CNC-ed lines are not on the same side). Not a big deal, but means I got to transfer some lines

Been there; done that, leading The Weezer’s S10 build to its first error… and learning to “transfer lines.”  . No idea how I managed to do this, but do it I did.  At least the kit can be forgiving. 

And, a satisfying ultimate success was the end result. 

[Bryan Rolfe]

Well, bad news. While going "3D" tonight, the plywood near the bow tore in much the way warned against in the build instructions. I did not use the hot wet rag method as suggested in the build-guide because my garage is not air conditioned, and the humidity here, near the ocean, is about 60%. 

The tare happened not while I was doing anything, but while I was looking for some clamps, I just heard a terrible cracking sound and looked around to see the horror at the bow. I think it was a result of the sides not being fully supported, and via gravity, putting a lot of force/twist on that section of the bow. 

However, I also was having an extremely difficult time getting the nesting bulkheads into position by myself -- is it even possible with one person? As you can see in the photos, I was attempting to use a ratchet strap to assist with this, and before the tare, I was getting ready to pass a board under the bottom and clamp it to either side to "force" the centerline up into the nesting bulkhead. 

 

In any case, I I have time to think about how to approach that, but right now I need to figure out how to repair this piece of plywood -- if it it's even possible?

 

[Bryan Rolfe]

Here's another photo prior to trying to insert the nesting bulkheads (and also before I removed one of the braces on the right). 

 

 

[Captain Tim]

I think the block with the two screws was your problem. the block should have had one hole with a bolt right at the end of the taped seam.

I think the two screws caused a hard spot in the plywood that could not bend.

 

[Bryan Rolfe]

Hmm. I was going off the build instructions which just specify to use a 2" square piece of 9mm plywood, or similar, and to screw them tightly together. The photo included directly under that part of the build instructions shows two screws in each of the blocks as well. It might be different for other builds. 

Anyway, wouldn't the hard point be formed by the edges/corners of the wooden block, not the screw locations? 

[Captain Tim]

You are probably right about the hard spot. I think the hole at the end of the taped part stops it from ripping open the seam. Looking at your plywood better I'm guessing you tortured the plywood to the max.

I really wanted to send the video so you could see the half mold of my Westsail 32' hanging on the wall. Great boat. Hope you have as much fun as my wife and I did on ours.

 

[Bryan Rolfe]

Haha, I never would have spotted that. Very nice -- I'd like to make a half-hull of my last boat, which was an Albin Vega 27. 

[Alan Stewart]

Bryan, defenitely repairable for another go folding. I'm out of town this weekend away from my pics from other builds but basically just glue the crack with epoxy and put a piece of glass over the crack inside and out and clamp nice and flat. At least half a dozen builders over the many years have sucessfully repaired from a crack during folding. Wait a few days before second attempt epoxy is still pretty flexible after 2 days. Full properties in about 7 days in my testing. I'd give it a full 72 hrs maybe a bit less if you apply some gentle heat. (Not more than 100 deg or so so). 

 

On the nesting bulkhead in this picture it looks like your ratchet stap is actually keeping the bottom from flattening. The chine edge needs to be able to extend past the corner of the bulkhead but the strap is holding it back. Instead just slide some boards under the keel at the bulkhead and support the keel at that point and the gap should easily close. That sounds like maybe what you were going to try next. 

 

 

[Bryan Rolfe]

Thanks for the reply Alan.  

 

For the repair, I ended "chamfering" down the plywood around where it had cracked (on both sides, but only one side is shown below).

 

 

I then traced the area on plastic, and then onto fiberglass cloth, and cut out incremental patches

 

 

Then on this same piece of plastic (since it acts as a guide), I wetted out the patch in order of smallest to largest, then took this wetted patch "assembly" and flipped it upside down so the largest patch was on the bottom. I then applied this to crack, added peel ply, and plastic. I repeated the process for the other side. 

 

After the patches were cured enough to not be tacky (overnight), I removed the peel ply and added an epoxy fairing compound to both sides, since the patches do not perfectly "fill" the chamfer. I then sanded these down to be flush with the surround ply -- I did sand into the glass a little since it was proud in some places. 

 

 

[Bryan Rolfe]

Once the repair had cured for 24 hours, I continued where I had left off, but with some new strategies. I wetted out the interior of the forward two lower panels with hot water and rags for ~45 minutes. I only wetted the exterior (as I should have probably) later. 

 

I also added a "batten" to the side that had not cracked, just to prevent something similar from happening. I ended up adding a batten to the repaired side too, but only later in the process. The photos below only show the forward section after I removed the starboard batten. 

 

 

 

 

 

For the most part things went well. To secure the nesting bulkheads, I used the rachet straps again, but instead I used them, with a board running along the underside of the boat adjacent to the nesting bulkhead location, and with each end of the straps hooked over the edge of the lower panels. I then racheted to "open" up, and flatten, the floor at this location, which allowed the nesting bulkhead to settle in place, and I could then use my screws to secure it. 

 

The only hiccup was again at the bow. I thought everything had gone well, but then noticed a hairline crack developing along the same extended line as the original blow out. I suspect that either the interior plywood was slightly damaged here when it originally tore, or the glass/epoxy repair has added a hard point which has caused this area to crack. After I noticed it, I liberally wetted out and steamed the area (with a steam cleaner) before proceeding to tighten up my wires. I also added the port-side batten at this time to maybe relieve some of the bowing stress here. 

 

 

 

The crack can be felt as a little "bump", even though it doesn't look significant in the photo. My question for Alan, or anyone else is, should I be concerned about this? The hull will ultimately be glassed, which will certainly help, but should I take other actions now, or in the build  to prevent this from worsening over time? 

[PadrePoint]

This area is inside the bulkhead that will be placed later, so inside aesthetics aren’t important.  Note: I am no expert in all this, I just offer a thought as to how I might approach this.)

 

The hull in the bow area should now be formed to the desired shape.  I’d be inclined to place a layer of glass onto the inside to back up the crack (and split) area. I might then back that up with a four inch wide 1/4” piece of plywood that could be pulled in in with a few Sheetrock screws.  I’d likely do both at the same time.  I think I’d feel confident with a repair like this. 
 

When flipped over for glassing the outside, I would think that any bump on the outside of the hull could be sanded out to be even and fair.  (Any screw holes can be filled then.)

 

By the way, The Weezer put in an 8” sealing port into the bow bulkhead for inspection and maybe to store something. Getting the cover off with the mast in place might be a little tight; I don’t know if she tried to do this.
 

Again, just my thought on this. 

[Bryan Rolfe]

That's a good idea in terms of re-enforcing the inside. My plan was, before I close out the forward compartment, do apply some glass on the inside, but also sand down the outside slightly and apply an extra patch of glass there as well. The bump is pretty small, but it would give me peace of mind to know the area has been toughened up. 

 

This morning I continued with the build and got the bow breast hook, transom, and transom knees installed and epoxied in place (epoxy is currently curing). 

 

Dry-fit:

 

I noticed that I made a mistake with the transom and cut the strengthening pine pieces flush with the transom, rather than chamfering them at an angle to match the hull shape. In hindsight, it makes sense that Alan would not have arbitrarily had these pieces cut oversized for no reason. 

 

It's not an issue, and I just made sure the gaps were adequately filled with thickened epoxy. I only mention it so others may learn from my mistakes.

 

My latest question is what I should do about the chine near the FWD bulkhead. The lower panel is still pushed out slightly on both sides, and I cannot get the copper wires tight enough to pull it in. 

 

 

I was thinking of adding a copper wire to the lower section of the forward bulkhead and pulling it from there on both sides:

[Alan Stewart]

Good job on the repair, i had little doubt you could repair and re-fold. I've seen the additional crack before too. I think gluing a ply doubler on the inside isn't a bad idea but I also think the normal keel fillet and chine glass and a bit of extra glass should be sufficient. An additional glass patch over that area on the inside would be a good idea as well. This will also give you some thickness there for when you eventually need to sand down the "bump" the crack created. Maybe do the keel and chine glassing first and then decide if you want to put the extra ply doubler over the new crack spot. 

 

As for the chine gap at the forward bulkhead. I think you should just live with it. The forward bulkhead has always been a tricky shape to fit to the developed ply which doesn't always bend exactly on the ruling lines we tell it to in the computer and also the computer can't take into account the slight amount of compound curvature that the ply does take on in real life. Gaps of say not more than ~1/4" on the edges of the forward bulkhead against the hull bottom are ok in my book. Thickened epoxy is a great gap filler! 

On the chine itself, I wouldn't worry too much about getting it to close that last little bit. If it really bothers you I would tweak the bottom of the forward bulkhead (take off some material) say at the keel where it looks like it's hitting in your picture but the most important thing is just getting it as close to the lines on the ply sides as you can and at the right height vertically. If it's sitting a bit high then yeah feel free to trim it a bit. Also, on the outside you can use a one sided block to pull the edge of the bottom panel in a bit if it's extending out beyond the side panel This helps keep the chine line from drooping at the bow if you do have a gap. Like the picture below. 

 

[Bryan Rolfe]

That's a good idea! I think you're right though, if I can live with it, then I probably will. once the fillets and glass are in on the inside, I should be able to afford to plan off the portion that sticks out while I'm rounding over the chines without compromising the integrity of the hull at that location.

I've been thinking ahead about what I want to do with the mast and sail, and I'm wondering what solutions are available to make raising and lowering the sail easier while in the dinghy, on the water? I don't have any experience with sleeved sails, but it does seem like lowering the sail isn't really an option with a sleeved design, or it has to be lowered and unzipped at the same time.  Obviously a track is out of the question on a mast that breaks down into 3 sections (right?). Are "hoops" an option, or is there too much loss in efficiency/issues with the tapering? We'll be using the dinghy as our tender, and anything that makes sailing it easier, including setup and breakdown, will mean we'll be more like to sail the boat, over motoring it. 

[PadrePoint]

Here is one person’s attempts. 

 

[Bryan Rolfe]

In that thread, I found the link to the seabiscuit build, where he used a lacing technique:

 

I think this method could work, although it does seem to be a bit of a pain for the initial setup. I imagine it probably works better, aerodynamically, than using velcro "straps" though.

The other thing I was thinking was to utilize and entirely different rig, like a sprit rig.

[Bryan Rolfe]

I'll be making the gunwales tomorrow -- unfortunately I can't fit 12' lumber in my car, so everything I have is < 10'. I'll need to scarf and glue strips together, and I think I'll make a temporary jig for that process to make sure everything gets glued together straight and flush.

 

My plan was to use some redwood strips I already have from a surfboard I built a few years ago. These are already 5/16" thick, and just need to be trimmed in width a little. For the outer layer, I was planning to use ash, since I happened to have some, and the assembly guide suggests it for durability of the outer layer. 

 

Any reason I shouldn't use redwood in place of fir here?