Jump to content

Spindrift 10n- Adding forward flotation


Starboard

Recommended Posts

The Spindrift 10n by it's very nature has less built in flotation than the non-nesting version. In order to nest the bow into the stern, the side seats must be removable to make room for the forward hull. The non-nesting version has no such requirement and the seats can be built in permanently and with water tight compartments which provide plenty of lateral flotation the entire length of the hull. When capsized, the 10 will float higher in the water and take in less water when righted than the 10n.

 

I've been stuck when my 10n capsized and I couldn't possibly bail the water out fast enough- I basically had to return to shore to recover properly as it was a very windy and choppy day. The flotation is adequate to prevent it from sinking, of course, but not quite enough to prevent it from scooping up a lot of water when righted. That's fine for me sailing on my own or with another experienced sailor, but since I have little kids who I'd like to take sailing I want a little more of a safety factor.

 

Graham, feel free to correct me if any of the below is wrong.

Top: The non nesting Sprindrift on top has plenty of flotation on both side as well as in the forward hatch.

Middle: The 10n as I built it has small flotation chambers in the stern as well as the forward hatch. Some people have built the stern chambers a little bigger to conform more to the shape of the bow. I didn't.

Bottom: I'll be restoring some of the forward flotation and it won't interfere with the nesting

 

spindrifts.thumb.jpg.b9f6ec31d94e227eeec49c4234c5ad37.jpg

 

 

 

I don't expect this to add too much to the total weight, if anything at all.  The 3/4" thick spruce seats are being replaced with 1/4" marine plywood on the top and sides, plus a few thin backing strips and some epoxy to hold it all together.

 

I built my 10n with removable forward and rear seats, which look very nice but don't add much in the way of flotation.

Spin_a.thumb.jpg.7a6939f52a6928b8bf7324fce8dc771e.jpg

 

I've decided to build in the forward benches and make them water tight flotation chambers very similar in design to the far aft flotation chambers. I have just a little bit of leftover marine plywood and spruce from the original build, and I thank I'll be able to get the pieces I need from it.

 

I very roughly cut the basic pieces to make the seats. I hadn't decided the angle for the side support. You can see the original line I had planned on- it matches the angle of the flotation chambers in the stern. My wife pointed out that it makes the footspace too tight for the forward crew- her, in other words. So listening to her advice I pushed the angle back to give a little more room. Yes, it will take away a little flotation but result in a happier crew. It still leaves enough room for the inspection ports I'm installing to give access to the nuts for the nesting mechanism.

Spin_e.thumb.jpg.4bebdc2b212de42b12c89da63865f867.jpg

 

 

I refined the shape to fit very closely to the hull. I then epoxied the backing blocks to strengthen the joints between the seat and the hull. I used a piece of scrap oak for the curved piece- it already had a bunch of curve to it and was already beveled.

Spin_b.thumb.jpg.04d5aa79cfb04074f611026377ba1a37.jpg

 

I have a unique mechanism for holding the seats in place using these custom blocks I built. This photo is from the original build before I painted the hull. They're fairly strong as they are screwed in from behind the bulkhead.

forward_bracket.thumb.jpg.09047166a9009abb855a9140d90703f7.jpg

 

I cut the tabs off and added some shims to get them to the correct height.

Spin_f.thumb.jpg.e476f394aca30f6af271d4ce3cfb4a45.jpg

 

 

Seats are glued in.

Spin_d.thumb.jpg.781e0746f4b86af871599c73581f4132.jpg

 

Spin_c.thumb.jpg.53f1786ef79ef7215d12879c41a4e29b.jpg

 

The next step is to install backing strips and then the side supports. I'll do a little fairing and then I will then paint it and install the inspection ports. I can't wait to see how it looks and how it sails with it's new carbon fiber mast- that's for another post.

 

-Starboard

 

 

 

  • Like 1
Link to comment
Share on other sites


Looking good.

The other way I've seen to add buoyancy to the bow section is to build in a compartment amidships encompassing the centreboard casing.

I've wondered about how the boat will cope when swamped. Buoyancy bags fitted low down in the bow section might be another approach.

Link to comment
Share on other sites

I like  the ideas here and those removable seats.

When I was contemplating a Two Paw build with a removable seat I was thinking about gluing/glassing foam under the seat as added buoyancy. I think you could do that with your removable aft seats to increase buoyancy even further- you might be able to put enough foam to achieve half the flotation of a built in chamber in the aft hull. They'll be bulkier to store but still very light. Maybe the last piece of the puzzle to achieve full self rescue?

Cheers

Peter HK

Link to comment
Share on other sites

I've epoxied in all the support strips and done the final shaping of the side support panels. I ran out of West systems 205 fast hardener, which is good down to 40ºf. I still have a bit of slow hardener but it is good down to 60º and it's been hovering around 62-63º during the day and will certainly be below that at night- it was getting down to 42º the other night. California problems. So a little trip to West Marine is in store this afternoon.

 

I'm looking forward to measuring how much extra flotation this will give. My visual estimate is 10-15 gallons of flotation per side. That should make a big difference when capsized, and when it's recovered and upright again will be a lot less water to bail out.

 

There's just enough room to install the hatches. Everything is ready to epoxy in once I get the fast hardener.

 

Spin_g.thumb.jpg.896633c3cfd61e7a9abe5bf0e53fa931.jpg

 

This phase always looks so messy but a coat of paint makes it look great.

 

 

  • Like 1
Link to comment
Share on other sites

4 hours ago, Starboard said:

This phase always looks so messy but a coat of paint makes it look great

I did the same thing 10 years ago to a non nesting dinghy. Made a huge difference re capsize and looked like a new one after paint.

Cheers

Peter HK

Photo 6...Capsized waterlevel AABB.jpg

Photo 5...Adding side tanks.JPG

Photo 9...Water in boat.JPG

Link to comment
Share on other sites

Peter,

That's exactly the flotation I'm looking for- I hope that my on-the-side waterline is similar to your upgraded dinghy. With version 1.0 of my Spindrift, the waterline is much higher- about up to the mast. When you right it, almost the entire boat gets scooped with water. Many other small dinghies I've sailed, like a V15, have lots of flotation built in and you can almost dry-capsize if you hop onto the centerboard quick enough. I don't expect that from a Spindrift- it doesn't have a self draining cockpit after all.

 

No boat can be all things for every occasion- there will always be compromises. The Spindrift is an incredibly capable small boat that is an excellent sailboat, rowboat, and motor tender. The nesting version notches it up one step higher by splitting itself in two and stowing in almost half the space. It's pretty amazing how clever Graham's design is. The compromises for the nesting version are as a little less convenience with the interior layout as well as less flotation than the non nesting version. I'm adding a fair amount of flotation back which will mitigate that compromise. This may not be an issue for some people as they probably won't be capsizing very often- but I plan on using this boat to teach my kids to sail and it's almost a guarantee they'll go over. I want them to have it easier to recover from the capsizes.

 

The side are epoxied on. Tomorrow I'll round off the sharp corners and get it ready for paint.

 

IMG_0683D.thumb.jpg.bda8a747a0f87386b615c222e408d616.jpg

 

 

Link to comment
Share on other sites

What if you attached flotation to the bottoms of the two back seats in a shape that would allow you to store them in the front half when nested ? If the back seats could float they would need to be held in very tight so they stay in place when capsized. Just a thought. As I wrote this I thought why not flotation bags that just deflate when not in use so no real storage problem. 

If kids learn that capsizing is fun it takes a lot of fear away when learning to sail.

Link to comment
Share on other sites

57 minutes ago, Captain Tim said:

What if you attached flotation to the bottoms of the two back seats in a shape that would allow you to store them in the front half when nested ? If the back seats could float they would need to be held in very tight so they stay in place when capsized. Just a thought. As I wrote this I thought why not flotation bags that just deflate when not in use so no real storage problem. 

If kids learn that capsizing is fun it takes a lot of fear away when learning to sail.

 

I'm thinking along similar lines. I intend to use eye-nuts rather than wing-nuts at the nesting bulkhead. I will also have pad-eyes on the floor near the aft seats, as lifting points.

The distance between these points is about a metre. I'm trying to track down a suitable inflatable fender or buoyancy bag that can be strapped fore and aft, one on either side. This would give useful extra flotation nice and low in the boat, and reduce the amount of water shipped in a capsize. And if partly deflated they would also create a nice padded cushion for the bow section to sit on when nested.

Hopefully what I'm describing makes sense- if not I'll show off my MS Paint skills :D:D 

Link to comment
Share on other sites

It's always amazing what a coat of paint can do.

 

IMG_0732D.thumb.jpg.c6d3205d110f2fd8b43a1c2507e51a90.jpg

 

I applied two coats of primer after all the epoxy had cured. Last night as I was about to prep the paint, I noticed that the daggerboard trunk had a little bit of a ledge on it, and wasn't a nice rounded corner that it ought to be. I'm not sure if it was built to plans that way or if it was an oversight when I built the boat seven years ago, but either way I decided to round it off and make it a nicer shape. This will be good for my little crew and also looks a lot better. I did two layers of epoxy last night and sanded it this morning, after which I applied the first coat of primer. That's why I skipped painting the top of the daggerboard trunk until tomorrow, to let it dry.

 

I figure since I was already painting the bow I might as well paint the stern too. I'm using the same Interlux Brightsides Hatteras Off White (1990) as I did seven years ago, but in the unlikely event the colors don't match exactly I'll have done both bow and stern. The stern had a number if dings and scratches too, so another coat of paint or two will cover that up.

 

IMG_0735.thumb.jpg.0ad22a88872886e891382c26ee57f3a0.jpg

 

I masked off the brightwork and the hatches, as well as most stainless hardware and the Harken cleats. I thought about masking the locknuts and washers but in the end I just painted them. The paint may not stick very well, but then again it'll probably be fine.

 

It's getting close!

 

  • Like 1
Link to comment
Share on other sites

  • 5 weeks later...

I have been thinking along the same lines for my Two Paw 8.  But I like to lay in the bottom while sailing.  Those rear seats would be annoying.  My solution for the rear chamber will be a removable box that goes clear across, side to side.  I’ll make it out of 4mm, since I don’t plan to ever sit on it.  Sorry, no sketches yet.  Been busy on other stuff.  I’ll probably do that next winter.  In the meantime, I’ll watch y’all’s developments.  
 

(I’m not a native “y’aller”, but I’m learning.)

Link to comment
Share on other sites

  • 2 months later...

Sorry for the very long delay in responding. We were at our house in Maine and to get there I had to drive cross country with a large cargo trailer- in which was my Spindrift which will now live in Bar Harbor for the next little while.

 

While we were there I got her on the water for a little ride- carried the halves of the hull down the rocky pathway to the even rockier shore. It was a little difficult boarding from the rocky ledges but we managed- the only one who got wet was me when I stepped on a slippery rock and went for a swim while getting ready to haul the boat out of the water.

 

As for the forward flotation, it looks good and functions well, but we didn't really have a chance to swamp and capsize the boat and see if it floats better.

 

1283284106_flotationA.thumb.jpg.245c89f73ba10f534c79d1be361ab868.jpg

Forward view of the built in flotation.

 

2106420908_flotationb.thumb.jpg.5d5ecaf8e5791045ed5a9195b22f3ea3.jpg

I really wanted to keep the nice fair sweep of the seats from fore to aft- it was a lot harder building it that way but I love the look of it.

 

1324459776_flotationc.thumb.jpg.5f5acd27816439c929500d5a30415783.jpg

I used the same inspection ports in the forward section as in the aft section- the plywood has a slight curve here but when I installed it I used a little extra 5200 in the middle and didn't tighten the screws too hard- so the actual bend is less than 1/32 on an inch. The foam seal on the hatch more than covers the rest.

 

1941900778_flotationd.thumb.jpg.f9c02babb0c6467ebb9bf31c0cac7bf3.jpg

Weight for the forward section is 55.9- maybe a little heavy compared to other builds but still about the same as before I built in the benches. The weight of the plywood was similar to the weight of the spruce seats that it replaced.

 

1796955445_barharborA.thumb.jpg.7b0981a863621f5bc511c56d0383f0a7.jpg

Here she is on Frenchman's Bay at our house in Bar Harbor, Maine.

 

799633015_barharborb.thumb.jpg.d40f8ed32536d40c9a43156f848a79d7.jpg

I repurposed my trailer cradle to fit on a Gorilla cart to walk to boat down to the shore from our house. The Tohatsu 6hp 4 stroke outboard fits in the cart. 6hp? Yup, that's what I have- it's actually a 4hp but I bought the 6hp carb for it since it also gets used on my J/24. The Spindrift handles it just fine, but I also have an older Tohatsu 3.5 2 stroke.

 

Link to comment
Share on other sites

I didn't get a chance to capsize it- the tide was coming in (10 feet in Bar Harbor) and I also fell in the water, so the real test will have to come later, since I'm back home in California.

 

The Gorilla cart is great- I bought it to pull the kids around, right? Of course I had other ideas, and it works perfectly- I couldn't have guessed that the outboard would fit with less than an inch to spare, so I lucked out on that one. The cradle also works with the boat assembled.

Link to comment
Share on other sites

  • 2 weeks later...

I somewhat expect the possibility or turtling to go up when the side flotation raises the mast up from the surface a little bit. I used to teach Sailing 1classes on Capri 14.2 dinghies, which are sealed fiberglass boats with a lot of side flotation when they capsize. They would turtle easily, which isn't great for a beginning sailing class. The solution was to basically seal the top of the mast- no problem since it didn't have any halyards or other lines down the center. That made them much more buoyant, but the could still turtle sometimes. Eventually they put mast top floats from Hobie 16s on as well. They never turtled after that.

 

I originally used my Laser rig, but I have since sold my Laser. I'm building a new rig using a heavy duty windsurf mast made from Carbon Fiber- it may or may not work, but I'll be sure to seal it up so it's buoyant too. I won't get to test this new setup until next summer, since my Spindrift is in Maine now.

Link to comment
Share on other sites

  • 1 year later...

@Starboardhow are you getting on with your modified Spindrift? Having just had a capsize yesterday I was a bit taken aback by just how full the boat was- and that was without the rig on.

 

Looking back on my previous comments on this thread, I had been talking about adding buoyancy bags in the stern. In hindsight I'm not sure if that would help much. Based on what happened yesterday, it's the bow that needs the extra buoyancy, because the centreboard casing is very close to being awash. I think raising the stern wouldn't help that much, if at all.

Link to comment
Share on other sites

  • 4 weeks later...

I did something similar to my Two Paw 8.  I did not alter the aft half, because I am a lazy sailor— I lay in the bottom of my boat when I sail.  I am pleased with the results.

First, I did a capsize test, beachside, with the original floatation scheme.  She took on a lot of water.A5D4541C-40DE-4C42-AD9C-FE565AAB5317.thumb.jpeg.e0505254681a8dc40d19ad6babcb8f5f.jpeg7876D21B-17F1-4DF8-853D-DFC7E4C59B53.thumb.jpeg.89052ff5d42eed40b406a9b4f72f6c6b.jpeg

 

 

Then, I added some temporary floatation tanks to the forward section.  (I wanted to test their effectiveness, before making the tear-up.). Much less water intrusion!CBE2805E-0CC5-49BF-9A03-F72B96D0EED3.thumb.jpeg.52bde1a5f6c7d5904188352dc3c327a3.jpeg8687C83E-75ED-4800-A92A-03B4F062A06D.thumb.jpeg.3ca90d48af5d82aa363bd5897e4157b8.jpeg

 

Then, I made my permanent changes, opening up the less-effective foredeck for open storage.ED968155-EEB2-4B8C-974C-1A729289B399.thumb.jpeg.5c8e2b5786fcbb76c68d2436f150afea.jpeg42A4DB0F-1F79-4258-B721-D67FFC6CBD15.thumb.jpeg.b5ab9ec1759dda11c1d286744697069d.jpeg

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...


×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.