Need some help repairing my daggerboards...

[catsketcher]

Cedar daggerboards are quite fun to make. You will need a power planer, some large clamps, circular saw, jigsaw and hand tools and nice bench.

To do the scarfs in a boatyard is harder as you will not have jigs. Set multiple planks back 10 times the thickness from each other. Use the power planer to remove the material on the end. As you get closer to the end stages switch to a long hand plane to get the final details right. It is not hard but look carefully to ensure the scarf is flat.

Getting the scarfs right on the board will be harder. Cut the board off (STOP here and see below - don't scarf straight away) and attack it with the power planer too. IF you go glass reinforced (and go glass reinforced) the scarf will not be critical - just important. I haven't scarfed a shaped board before and it will be trickier than the planks. Do the planks first.

(When you have the board nicely cut off and you are about to get the scarfs made on the board get some scrap ply. Draw and cut out a template of the board on this ply. This scrap will be your template for the bottom of the board)

Then glue the whole lot together. You want the epoxy to squeeze out when clamped - not peanut butter consistency, but not runny honey. Somewhere in between. If you can't get clamps use small timber pieces with wedges pushed in. You can make any type of clamp you need with scraps and wedges. Check for straightness at the join - be very careful here.

Carefully align the template with the rest of the board and nail it onto the bottom. Run over the board with a 7 inch polisher with 40 grit paper and just clean up the glue and edges. Any grinder will do.

Use the circular saw to make cuts up the board. Start at the base and set the blade depth just above the template. Run up the board. You don't have to remove all of the timber. Just give yourself some depth guides.

Then go back to power planer and carve away. When you get close to the guides you will be getting pretty good at this. Be careful again as power planers are very nasty if you get them on their sides at all. Move to the hand plane when you get close after reducing depth on the power planer.

You will then need to make the board straight. Use the template end and the top as you datum ends. Find a straight piece of angle iron. Run it over the board, up and down. This will show high spots. Rusty angle iron is best as the rust marks will stay on the board. Plane down the high spots.

Eventually you will get close BUT YOU DON'T WANT THE BOARD TO BE STRAIGHT! After the board is perfectly straight sided you attack it again with the hand plane. You need to recess the middle for the uni reinforcing. I have 6 pieces of 400gm uni - about 3mm worth when packed together. This tapers up and down.

Then you are onto glassing. Unis first and then a layer of 600gm db over the lot. The back of the board is always tricky. I like to get some sheathing cloth (like surfboard cloth) and cut it at 45 degrees to the roll in 10cm strips. They accordian like crazy. This is really light double bias cloth you make yourself. Use a couple of layers of this on the trailing edge. 600db will have voids. Then fair and you are away again.

Get started with scarfing. Things will fall into place if you take things sequentially.

cheers

Phil

[UNCIVILIZED]

I'm hoping that you realize that if you have access to a decent amount of say Douglas Fir, you could use that to make entirely new boards. Glassed over of course. Ditto any number of other woods. And that the "difficult" part of the build is the foil sections. So that were you to do build entirely new boards, it wouldn't be much added work.

Anyway, don't rush, build everything & execute each step in your mind a few times before you reach for your tools, & good luck. Plus of course ask us if you need anything.

[Cavalier MK2]

Dick Newick often had the first third of his boards Douglas fir for impact resistance and extra strength. The back 2/3rds was cedar. His trunks had crush boxes to take the impact of hitting a rock at speed but if it went beyond that the cedar part of the board would give way before the trunk.

[Sunsetslim]

Originally Posted by catsketcher

Cedar daggerboards are quite fun to make. You will need a power planer, some large clamps, circular saw, jigsaw and hand tools and nice bench.

Sweet. Exactly what I needed. Thank you very much. I've got the boards epoxied together and as soon as I clean them up will nail the template. Sounds pretty straight forward. I've got the tools.

Again, I appreciate everyone's input. I've got cedar, so I'm going with that. Nice to know other types of wood are fine.

What are your thoughts on using biax instead of uni? I just can't get uni here, and it'll take forever from the states. Is it a big deal? I've got heavy heavy biax and not so heavy biax... If this will work to reinforce I'd prefer to use what I have. What say you?

-James

[Ken Z]

use what you ve got. epoxy raw wood , let dry to tacky use the thinnest glass first, then thicker glass. good luck

[44'cruisingcat]

Originally Posted by Sunsetslim

Sweet. Exactly what I needed. Thank you very much. I've got the boards epoxied together and as soon as I clean them up will nail the template. Sounds pretty straight forward. I've got the tools.

Again, I appreciate everyone's input. I've got cedar, so I'm going with that. Nice to know other types of wood are fine.

What are your thoughts on using biax instead of uni? I just can't get uni here, and it'll take forever from the states. Is it a big deal? I've got heavy heavy biax and not so heavy biax... If this will work to reinforce I'd prefer to use what I have. What say you?

-James

Biax will work, but 1/2 of the fibres won't really be contributing as much as the other 1/2.

Orient the fibres at 0 and 90'.

Be very careful to not make the board too big for the case. Better to aim a little on the small side. If it's loose it's easy to add material. If it's tight you may end up sanding off structural material trying to get it to fit.

[catsketcher]

It is possible to make your own uni. Cut the glass into strips about 300mm wide. Then pull the crosswise fibres out one by one. It will reduce the bulk. You may have to leave some in

[Cavalier MK2]

To be honest at a certain point it is worth while spending a bit more and waiting longer to do the job once versus the quick patch and later new build. One can scratch the head and contemplate splitting differences and running biax 45 degrees or just order what you need in wood, epoxy and fibers to do it right once. It comes down to economics, timelines etc.... Do you need to get out of Dodge for seasons or safety or can you embrace a wait and explore till the materials arrive? I've sailed with field repairs but it was always because of a time line. Some of them last forever but you always wonder which detracts from the fun. In any case the practice will make you a better sailor.

[UNCIVILIZED]

There's some great info on building boards in this thread, some of it useful even if you've already built your new boards. http://www.cruisersforum.com/forums/...ml#post2067761

[ronazon]

Were you able to get her fixed up?


Following on YouTube. Hope it's working out.

[Cormorant]

I stumbled on this thread late, but I'll post this link here just for future reference. . . . It's a handy technique for getting good NACA section foils. Basically you draw out your foil shape and build a router jig to match. Run the router back and forth on the jig over your lumber and you get a good foil shape. I've used it for both rudder and leeboard on my boat.

Duckworks - Another Approach to Shaping Foils

[UNCIVILIZED]

Originally Posted by Cormorant

I stumbled on this thread late, but I'll post this link here just for future reference. . . . It's a handy technique for getting good NACA section foils. Basically you draw out your foil shape and build a router jig to match. Run the router back and forth on the jig over your lumber and you get a good foil shape. I've used it for both rudder and leeboard on my boat.

Duckworks - Another Approach to Shaping Foils

An interesting idea to be sure! Just be certain to deduct for the board's reinforcements thicknesses when building the jig. Especially if the amount of added reinforcements vary in different locations on the board.