Pegging for part sandwiches

Hey pals,
If I’m gluing several layers of material together, like the spacer and cheeks for a kick up rudder, I like to dry fit the parts, clamp ‘em tight and drill two through holes. Then when I’m gluing the stack together I can pin them with dowels to align them and keep things from sliding around when I turn my back. After cure dowels are cut flush.This leaves dowel end grain exposed but the outer surfaces are then encapsulated in epoxy.

Can anyone dream up a scenario where this would cause a problem?

Also, does anyone who has already built one have tips for building CLC’s kick up rudder?

Thanks,

e


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RE: Pegging for part sandwiches

That's a classic woodworking technique.  In old wooden boats, they pegged the scarf joint on the keel with pegs called a stopwater because if water weeped up the scarf, the softer wood would swell up and plug the leak.

But I digress.  I would definitely use a red oak dowel, which are easily available at big box stores.  It will accept epoxy or waterproof glue readily.  When pegging, I also take a moment to align the end grain of the peg with the grain pattern on the part if possible.  Red oak has high shear strength, and will be more dimensionally stable to match the plywood parts.

In some ways it's actually a better solution than using fasteners which could have corrosion issues.  There was even talk on another thread about using screws just until the epoxy cures, then backing them out and pegging the holes.

RE: Pegging for part sandwiches

I pegged the rudder for my Skerry when I built her SS and it was one of the best ideas I had.  Everything went together very simply. I don't know about tips, I just cut the bits and glued them together  :)  however I did encapsulate a bit of platic pipe in the build to allow the rudder pull down line to move a bit easier and I did my best to make sure the inside edges of the cheeks were as smooth as I could get them after epoxying them. 

RE: Pegging for part sandwiches

   

It’s usually a good idea to follow CLC recommendations when building. Every time I’ve departed from said to make a “stronger” boat I’ve only succeeded in making a heavier boat and more complex build.
But I keep trying.

As you said Yambo, pegging the cheek spacer assembly worked great!

I didn’t like the idea of having rudder blade pivot bolt threads eat away at the drill fill drill epoxy hole in the blade. It will see a lot of use (yes, that’s a brag;-)

Outside of each cheek and both sides of kick up blade got a shallow counter bore with a forester bit. I had one to exactly fit OD of fender washers in the kit. Washers sit not quite flush with surface they mate with but are well enough seated to stay in place. They’ll get epoxied in place. This will keep the pivot bolt riding on metal tracks and should protect the epoxy fill. It was a real head scratcher drilling both sides of cheeks and blade so the bolt passes through perpendicular and washers are exactly coplanar. Drill presses are good, presses with no runout in the chuck are great.  Wish I had one.
Insides of cheeks have three layers o pox with the last being cabocil/graphite mix. Blade will be entirely covered with same. I found if I hit the timing just right I could smooth the surface of cheeks nicely when the goop was stiff but still movable. I’ve been careful to keep the same number of epoxy coats on spacer between cheeks and cheeks the same. That should make a perfect fit for the blade to slide easily. It’s been a fiddly process with a lot of short little steps dictated by cure time but I’m in no hurry. It’s still winter here. I can post pics if anyone cares.

Next up, figuring out a bomb proof break down system for the yoke. Anybody?

RE: Pegging for part sandwiches

   In a separate post about tillers https://www.clcboats.com/forum/clcforum/thread/40789.html  I show a picture of how I beefed up the rudder head and used a large 1.25 inch oak dowell as a removable tiller arm to replace the yoke.  I hated the idea of having to store an unwieldy "L" shaped rudder/yoke thing forevermore.  Now I shove my kick-up rudder, tiller arm and dagger board all into the sail bag that came with my NE dory sail, with a piece of closed cell foam slid in between the rudder and daggerboard just to keep them nice. Makes a nice flat package about 2 inches thick, and maybe 18x40 inches (or whatever the dagger board dimensions actually are).  The sail bag isn't long enough to tie shut, but that is little matter.

 

RE: Pegging for part sandwiches

   Bubblehead, good idea. I like the dowel but have in mind something a little different. I will definitely use the lashing technique. Could only think of metal fixtures, line is better, thanks.
What did you determine about the "bite" of your extra large rudder compared with the stock version? On the up side, it is easy to replace the kick up part of rudder at any time.

RE: Pegging for part sandwiches

"Everything that can go wrong..."

When I was coating my CLC kick-up rudder cheeks before final assembly, I made the mistake of leaving the areas to be glued mostly bare.  This was suggested in assembling parts of the CLC Teardrop to increase adhesion so, what could go wrong?.  After "several" (four) coats of epoxy on the blade, itself, it was too thick to slide between the cheeks.  Had I coated the surfaces to be glued, I assume the build-up would have allowed the blade enough space.  CLC was kind enough to send me a new blade gratis, but I have had to sand much of it down a lot to clear the cheeks.  I will be using a carbon mix on that portion to strengthen it, but I have also had to use some fiberglass cloth to reinforce the now-thinner wood on either side of the hole drilled for the cord used to raise and lower the blade.  I will keep the too-thick blade hanging on the wall as yet another reminder to "measure three times..." 

 

 

 

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