I lost my DS III centerboard!

Regarding the DS3 only. Note that the DS3 is not a class-legal Day Sailer.

Moderator: GreenLake

I lost my DS III centerboard!

Postby SMichelsen » Wed Nov 11, 2020 12:26 am

I was taking my DS III out for one more trip around Rehoboth Bay today. It was at low tide so I was certain to NOT secure my centerboard, in case it contacted the bottom. What I was not expecting was a hard strike that shook the boat. I found the steel cable that connects to the CB torn off in the cuddy. I brought the boat in and hoisted out of the water with my club's crane. The centerboard was GONE! Well that's the end of my season, for sure. Now the question is, how to replace it economically? I see that DR Marine sells them, with no hardware or even a hole drilled in it, for $600. Yikes! Any suggestions? I

I have learned today that the steel cable that raises and lowers the CB is apparently its only real connection to the boat, and that the pin that the CB rotates on is not actually attached to the hull; it simply rests in a slot. I guess the strike was enough to break the pin allowing the CB to break free.

Thanks,
Steve
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby tomodda » Wed Nov 11, 2020 1:08 am

Build one. GreenLake posted instructions around here somewhere. Nice winter project!

Warning, if you don't have access to the needed tools, then it'll be cheaper to just buy one.
tomodda
 
Posts: 450
Joined: Sun Aug 12, 2018 9:04 am

Re: I lost my DS III centerboard!

Postby SMichelsen » Wed Nov 11, 2020 2:33 am

Tomodda, thanks for that. I will look around for Greenlake's file. I have plenty of woodworking tools here; I assume that's what you meant.
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby GreenLake » Wed Nov 11, 2020 5:40 am

The "slot" that the pin rests in should have had a metal bar across it, with a screw on either end. See whether you can't see evidence of that.

In any case, you would have to secure a suitable pivot pin. The one thing I'm not sure of is whether the pin should go in a bushing or epoxied into the blade.

Other than that, the details are similar to a rudder. However, while I built a rudder successfully from plywood (it's still hanging in there), I would not recommend that approach for a centerboard.

For that you start with some suitably rot-resistant and suitably strong would that you rip into slats. You then assemble them into a board by stacking them so the cross-grain alternates (and the long direction of the slats aligns with the centerboard). There's this special waterproof wood glue (resorcinol-formaldehyde) that would be ideal for something that's immersed. Better than epoxy or Titebond. (Epoxy is generally a good glue, but it can separate from waterlogged wood).

Once you have a board, you need to cut the correct outline - details and drawings to be found on the DSA main website https://daysailer.org as part of the bylaws. (Above the bottom of the hull it's squared off with rounded corners if memory serves). You then cut the tip off at an angle and glue it back on. That glue line will impede any water wicking up the board should the tip get damaged.

Then you need to locate a suitable foil shape, something like the NACA009 profile. You need to find a way to take the correct excess wood off to be left with the shape you want. (The part above the bottom the hull should not be shaped and left flat).

Finally, you drill the holes for the pivot and attaching the cables.

Now you can seal the whole board in epoxy and also give it a very light sheath of fiberglass. After that you can fair and paint it.

One thing that some people do is to route a shallow channel running the length of either side at the widest part of the board and embed a couple of layers of biaxial or woven rovings, for extra strength in a crucial direction).

In a way, from a woodworking perspective it's just a specially shaped cutting board. :)

There are some old DaySailer Quarterly magazine articles on how to build one, but you may have to spring for DSA membership to access the archives. (A steal at $35.00 and also funds the hosting of this forum - if you do, be aware that the two sites use unrelated and therefore potentially different username/password credentials).
~ green ~ lake ~ ~
GreenLake
 
Posts: 6028
Joined: Mon Jun 18, 2007 3:54 am

Re: I lost my DS III centerboard!

Postby jalmeida51 » Wed Nov 11, 2020 10:10 am

Steve,

I have an old c/b from my Daysailer 1 and you can have it free. Pay the shipping via U.P.S. It will be over $100.00 to ship it from Florida to Delaware. You will have to figure out where to drill the pivot hole. The only thing wrong with the c/b the square hole is worn which shouldn't effect you. PM me if you want the c/b.

Good luck,
John
jalmeida51
 
Posts: 142
Joined: Fri Mar 02, 2018 9:51 pm

Re: I lost my DS III centerboard!

Postby tomodda » Wed Nov 11, 2020 10:39 am

Steve: There you go, John appears to be your Good Samaritan for this issue. Good luck, and thank you John!

Just for future reference, one way to carve out your NACA profile, assuming you have an electric router, is to use wooden "ribs." Make a series of plywood templates (1:1 scale) of your intended profile at - say 6-inch intervals along the CB. Half-profiles, actually. Glue the profiles to your board blank, every 6 inches, perpendicular to the board. Then run your router across the top of each template/rib with your bit set to carve into the blank at appropriate depth. Voila! You've carved the CB to the same profile as the template. Cut off the ribs and use a chisel and sander to cut away the remaining wood (under the template). Done.

Anyway, just throwing that out there. Reusing John's CB is easier, even if you gave to rebuild the pivot hole.
tomodda
 
Posts: 450
Joined: Sun Aug 12, 2018 9:04 am

Re: I lost my DS III centerboard!

Postby SMichelsen » Wed Nov 11, 2020 1:35 pm

John: That's a fantastically generous offer - I will surely take you up on it. I will PM you with my address and such shortly.

Given that I will be setting up a new CB from scratch, I may look at the idea of creating a raise/lower mechanism similar to the DS I/II - an arm, rather than a collection of lines, pulleys and cables. For me there are three advantages - the arm is just simpler, it more clearly indicates the position of the CB, and the CB would then be physically attached to the rest of the boat, rather than resting on a pin sitting in a cavity, just waiting to be broken and lost with a good enough bottom strike. I suppose one could argue that if I had the same thing happen with a CB that WAS more secured to the boat, there could be more damage. I am not sure that's enough to dissuade me. Any thoughts on this whole concept?

If there's anything good about this incident, it's that it happened on what was likely my last sail of the season, and not the first! I still can't figure why it happened - I didn't secure my CB, allowing it to bounce up and float down in the likely event of contacting the sandy bottom. Rehoboth Bay has it's share of "stuff" on the bottom - abandoned crab traps and such - maybe the CB got caught up in something that didn't belong down there. Will likely never know.

Steve
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby GreenLake » Wed Nov 11, 2020 5:50 pm

Shallow water is usually not a problem here, only the last few feet as you approach the beach. So I usually don't care. There are a few isolated boulders strewn about, and one day I confidently told my crew that we wouldn't hit a particular one of them, when "thwack!". On a DS1, the CB is held down by friction, so it can always kick up. Mine showed a nice dent near the tip that I took care of the next time I had the boat on its side.

You can purchase the bronze lever from D&R. You would need to fashion a bronze plate w/ a square hole to insert into your CB, to make the connection between board and handle. This needs to be well-anchored, because the forces are big.

The main advantage of doing your own CB would be in better hydrodynamics (foil shape), so it's worth reading up on that subject. Having a used one for the interim allows you to approach your project with deliberation and forethought, which means it'll turn out awesome.
~ green ~ lake ~ ~
GreenLake
 
Posts: 6028
Joined: Mon Jun 18, 2007 3:54 am

Re: I lost my DS III centerboard!

Postby SMichelsen » Sat Nov 28, 2020 11:11 pm

OK, I have received the centerboard from John. I took a little video of the underside of my DSIII, pondering the install process. Here it is: https://youtu.be/hW-TdyD7C6c
I had planned to rebuild the raise/lower mechanism to work as a DS I would, with the handle rather than the cables and pulleys. I was talked out of it by a guy with a lot more experience than I at my sailing club. So then as I see it, the steps are to:
- Order and wait for the cabling and CB pivot pin from DSMarine.
http://www.drmarine.com/proddetail.asp?prod=DS106b
Once the parts arrive,
- Figure out where the hole needs to be on the CB, so that it sits squarely in the DSIII trunk
- install the cabling and pin to the CB
- remove the plates and blocks under the boat, install the CB, replace the plates and blocks.

That's the jist of it, at least. I BELIEVE I can calculate the spot the new hole needs to be (assuming the old hole won't just work) by measuring the distance to the top and front of the trunk from the location of the pin. Even better would be to have a schematic of the DSIII CB that lays out the dimensions...
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby SMichelsen » Mon Nov 30, 2020 9:13 pm

I spoke to Rudy at DR Marine. He warned me that he thought that the centerboard trunk on the DSI is somewhat wider than that of the DSIII, so the DS I CB might be too wide to fit in the DSIII. I am beginning to believe he's right. Hopefully at worst, this means a sanding and refinishing job for me, to make what I have thinner. Please see the photo of the CB; I took some measurements of the widest part of the board. Also see this video wherein I peer up into the DSIII trunk from below, ruler in hand... Any thoughts are much appreciated.

Steve

By the way, pardon my ignorance but can you please confirm which side of the centerboard faces forward when going through the water? I -- THINK -- it is what is seen as the top in the picture; is that correct? If so then the CB rides in the trunk the same orientation as in the picture, yes? Also, the measurements are taped to the CB at the thickest part.

Watch the video under the boat here

DS_I_centerboard v2.jpg
DS_I_centerboard v2.jpg (155.46 KiB) Viewed 543 times


EDIT: I see now that the flat edge is DOWN when installed. I checked my crane video and there was the answer.
This is good, as most of the taper is on the curved side, and should fit well into the tapered trunk. We shall see.

straight_edge_down.jpg
straight_edge_down.jpg (78.26 KiB) Viewed 540 times
Last edited by SMichelsen on Fri Dec 04, 2020 12:23 am, edited 6 times in total.
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby GreenLake » Tue Dec 01, 2020 12:20 am

I'll have a look when I'm back at my desk. Currently at the remote storage site for my boat which does not have good connectivity for extended viewing.
~ green ~ lake ~ ~
GreenLake
 
Posts: 6028
Joined: Mon Jun 18, 2007 3:54 am

Re: I lost my DS III centerboard!

Postby SMichelsen » Thu Dec 03, 2020 11:54 pm

I had hoped to do a test fit of the DSI centerboard today, but there was only daylight enough left to remove the hardware that holds in (and holds up) the centerboard pin. The bars and supports were covered by all manner of caulks and waterproofing products - mostly unnecessary, and only made the job of removing it all that much harder. Tomorrow I plan to use the club's crane to lift the boat a few inches, move the trailer forward a few feet, place a sawhorse under the stern, and lower the crane JUST ENOUGH to stabilize the bow and stern on the trailer and sawhorse, while leaving space to access the trunk. This should reduce reliance on the lines holding up the boat.

Here's the bits, getting removed from the boat and out, waiting to be scraped clean.

removing_the_hardware.jpg
removing_the_hardware.jpg (227.11 KiB) Viewed 541 times


centerboard_retaining_hardware.jpg
centerboard_retaining_hardware.jpg (158.78 KiB) Viewed 541 times
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby SMichelsen » Fri Dec 04, 2020 5:45 pm

Here's today's update. I can now authoritatively say that a DS I centerboard does NOT fit into a DS II/III CB trunk.
I used my club's crane to set the boat on the ground, then tipped it on it's side to access the bottom. The picture of the CB shows how far it can fit in at this point. On the next nice day, I will set the boat up like this again, and bring along a belt sander and power planer, and flatten out the CB until it fits.

checking_the_centerboard_4.jpg
The boat held up by two of three lift points
checking_the_centerboard_4.jpg (228.33 KiB) Viewed 528 times


checking_the_centerboard_1.jpg
also a post provided backup support
checking_the_centerboard_1.jpg (131.64 KiB) Viewed 528 times


checking_the_centerboard_3.jpg
Here's how far the DS I centerboard fits. It needs to be flush with the hull.
checking_the_centerboard_3.jpg (171.67 KiB) Viewed 528 times
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby SMichelsen » Sun Dec 13, 2020 10:34 pm

Today I shaved down the DSI centerboard to fit (with a tiny bit of slack) in my DSIII CB trunk. I believe I removed about 3/8" of thickness. I used a power planer and a belt sander. I cut MOSTLY through fiberglass but did go through to wood in a few spots. Can someone recommend a paint to seal and protect this CB? Please note that the boat does not live in the water, so exposure to the sea is limited to a few hours at a time. Here are a couple of pictures from today's adventures. I am still awaiting a delivery from DR Marine of CB hardware and cabling, at which point I will sort out a spot to drill a new hole in the CB and install it into the boat.

One awesome aspect of this project is having the run of my deserted sailing club - working on the boat at the edge of the water, making use of one of the two cranes for hours, was quite the luxury.

planing and sanding CB to fit in trunk.jpg
planing and sanding CB to fit in trunk.jpg (177.9 KiB) Viewed 403 times


lifting the boat.jpg
lifting the boat.jpg (214.85 KiB) Viewed 403 times


boatyard.jpg
boatyard.jpg (193.02 KiB) Viewed 403 times
SMichelsen
 
Posts: 27
Joined: Sun Mar 18, 2018 1:29 pm

Re: I lost my DS III centerboard!

Postby GreenLake » Mon Dec 14, 2020 12:30 am

For sealing the wood use neat laminating epoxy. (Neat: as in unadulterated). You do want a vapor barrier - just make sure to seal the whole board, including the inside of any holes.

Simple as that. You do need to cover the epoxy from UV - for a CB that UV exposure is limited, but over the years some parts even of a retracted CB will accumulate enough exposure, unless your boat is garaged.

Almost any paint will do on top of epoxy, even cheap spray paint. Only problem is that most paint will be at risk of scraping off when you lower the CB. I believe if you used Pettits EasyPoxy (and let it cure for a weak or two) it would be tough enough to handle the stress. (I used some on the bottom of a silverware drawer and all the kitchen tools are thrown loose on the bare paint: it stood up to that test amazingly well, better than the cheap laminate surface that the furniture maker had been using).
~ green ~ lake ~ ~
GreenLake
 
Posts: 6028
Joined: Mon Jun 18, 2007 3:54 am

Next

Return to Day Sailer III Only

Who is online

Users browsing this forum: No registered users and 1 guest