Kit E76: Creating a Daggerboard Jig 

You are welcome! We share our triumphs and failures. :)

There are always other ways to accomplish things, sometimes even better, but we have to pick one and get to work.

Thanks Gary, we'll keep them coming.

We'll get to that soon, but this week... finishing the canoe with Coppercoat!

That’s great!

Thanks!

I'm a little confused. We created a blank, then built a jig with a cutout of the exact curve of the board, with slides on either side so the router moves along the shape of the daggerboard in one sweep. Then we'll use the router to take slices out and a curved sander (its foam) to smooth our between grooves. Isn't that what you just described?

Thanks for the suggestion, but yeah, our sled slides easily with the push of a hand and glides a few feet afterwards. Smooth as butter.

We generally use peel ply so amine blush isn't a problem.

@@SailingSVLynxyeah. There was just one point in this video where you mentioned sanding down the smooth surface of the epoxy before gluing beams together. Gougeon brothers (makers of west system epoxy) recommend removing blush before sanding. They say sanding might just spread the blush around and then it will be harder to remove because it will be in the deep scratches. I 100 percent agree that removing peel ply leaves a blush free surface.

Ah, that part. Well, if we had been sanding lightly with sandpaper, that might be of concern, but we were taking of a significant layer with a sanding disk on a grinder. Trust me when I say that no blush was left over. We could have saved ourselves some work if we had used peel ply, which we would normally do, but that was at the lot and we were at my garage :) We'll be using peel ply on the outer skin of basalt though.

@@SailingSVLynx Gotcha, LOL! I wasn't too worried about it anyway because there is so much surface area on that joint there is really no way for it to go wrong. I just thought I would share the info.

Our router setup is adjustable to any depth or angle, and can be set on the form for reference to the daggerboard shape. You'll see this in an upcoming video.

My thoughts exactly. Making the full leading-edge-to-trailing edge profile then running the profile, sliding the sled, rinse repeat. Since there are no concave surfaces in profile you could use a 2-3" cutter as well!

Unfortunately, I don't see how that would work.

@@SailingSVLynx here goes nothing .... 😊 You build the sled with two matching "fins" that the router base can rest upon. The fins are situated 90° to the travel of the sled. The fins are profiled in such a way so as to follow precisely the contour of the dagger plus the depth of cut. Which eliminates any adjustments between passes. Every part is static, the only variable is the depth of cut. So the sled can be anywhere along the gantry rails and the router can be placed onto the fins with no fear of cutting too deep. (unless of course the collet becomes loose and the bit extends, just ask Bono over at Sea Camel 😁) Then as far as how it gets accomplished, each of you would pass the router to one another athwart the dagger as you incrementally slide the sled astern. Pass the router, receive the router, slide the sled, pass back the router, rinse repeat. 😉 It's conceptually the same but profoundly different so-to-speak. You are cutting the entire profile in one pass. Then sliding the sled. Rather than sliding the sled then moving the router into position each time. I had an old faithful Bosch 2 1/4 horse with a custom fit slide fence that worked a treat for box work such as this. Because you always want to avoid having the cutter come into contact with the inside of the fins. Some router bases have template inserts that achieve the same goal. I'm of the opinion that it is not 6 one way half dozen t'other. Simply because you are not constrained by affixing the router to a new position with each pass. Thereby eliminating any squared corners along the parallel cuts. The profile will be very smooth and easy to overlap. But I'm sure that either method will get you where you need to go eventually. -Love the content. - Hate the local fiefdom being poop chutes. -✌🏽

The issue I see in the method you describe is that the daggerboard is tear drop shaped, not flat. That means the router plate is not sitting on a flat surface on the form guide, and could 'rock' as you pass the router back and forth by hand. If that happens, and we believe it would, the router bit will dig into the board deeper than we want. By fixing the router in position before sliding it down the full length, the human element is removed and the router will remain at the angle we set off the wood form at the top of the jig. Secondly, the board is 12' long (367cm). If we did it by your method, we would have to pass that router back and forth approximately 288 times (half inch router bit). The boards are 24 inches wide, which means we will have to set the router position approximately 48 times by going the full length with our sled. I'm do believe your method would work if we were perfect but I'm sure we wouldn't be. Those are the reasons we choose to go with our fixed position, full length sled cuts.

@@SailingSVLynx Thanks for the reply (and thanks for reading my wall of text). The next day I realized I left out the router base detail. Where you would attach runners at the leading and trailing edge perpendicular to the travel of the cutter. Describing a 3 point fixed position of the cutter relative to the sled and preventing swivel. Which then means mentioning to over run the fins to accommodate the leading and trailing edge at the end of each cut. And since it is mostly foam and not white oak it seems feasible to use a bottoming cutter with a larger diameter base. As for the amount of passes, well that's baked into the length of the D-boards so I suppose there's nothing to be done. And lastly I declined to edit my novel under the assumption that the work had already been done considering a recollection of seeing them glued up several weeks ago. Looking forward to many more episodes!!

I'm not sure where you got 0.5mm, we don't need that kind of accuracy. The casing will have a 5mm gap around the board, as the in the design plans. The plans specifically state that we should not make the boards too tight in the casings. And, after the boards are shaved down o approximate size, they will be further sanded. At that stage we will check the actual measurements to make sure the two boards are as close to the same size as possible. Then, after wrapping the boards with basalt, they will be faired and sanded again, allowing us to again adjust the thickness slightly to make the boards match.

@@SailingSVLynx If you had access to a milling machine and maybe more important use vacuum bagging the fairing should be minimal. However a 5 mm gap doesn't allow for 5 mm tolerances as you probably know. The boards must fit the casings on the entire width to not create hot spots for pressure and stress in the fibres, which would lead to short or long term cracking the boards. So a 0.5 mm tolerance is not overdone and you may achieve this with your method as well. However it would be faster with better quality if the core was milled and the laminate was done with vacuum bagging. This gives the laminate also a lot more strength as the resin is reduced and the fibre layers get closer together. Stress can be transferred easier from layer to layer this way. Resin is not designed to take the same amount of stress as fibres as you know, therefore for high performance parts such as the boards and the forward beam from carbon vacuum bagging is a must.

@@Hotzenplotz1 I'll say that vacuum bagging is desirable, but not a must. We already spoke to Schionning about it and they agree that we may roll them and the boards will be fine. I don't have the budget to setup vacuum bagging for just one instance in this boat project.

@@SailingSVLynx Not for a single project on this build, for the entire boat it would make sense. You could save some 15 to 20 percent of the total composite weight. Which saves directly money with less EP used. An experienced composite worker can do a quite good laminate without vacuum, the point is that you are not an experienced worker and you don't have one around. And I clearly disagree with Schioning on high performance parts like daggerboards and cross beams. The strength of high modulus fibres like carbon or basalt is reduced by the same ratio as the weight increases without vacuum. Therefore it's an absolute no brainer to build an cross beam from carbon in two half's without vacuum and gluing them together without a real propper bonding laminate. I'm a naval architect and have been in regatta boat building, now doing superyachts. The extra money for the carbon instead of glass spend on the cross beam is just wasted and still with glass high performance parts are possible if you want to. But I see you thrust the yard and your own research more than someone from the net. If you ask any high performance boatbuilder on the circumstances described, they will answer you just the same.

@@Hotzenplotz1 We have a kit boat. The entire kit was vacuum bagged when made. There is very little left to create in glass at this point. As for trusting Schionning, yes, we do. They have been making catamarans for a very long time, and are known for their strong and fast designs. And yes, they recommend vacuum bagging the daggerboards. However, that being said, they also said that it will be fine if we roll them in our case as we don't have the budget to vacuum bag them since that is nearly the only thing left to build that would need it.

The packaging tape we put down first is making the lithium grease work well, but we didn't think of paraffine.

We purchased some inexpensive micro fiber rollers on Amazon, they seem to hold up fine for applying epoxy, though I wouldn't use them to pain anything. Just search on' 300 micro fiber rollers', it's the first one that comes up.

I understand your confusion, but it isn't the form on backwards, the board was laid down backwards. We weren't cutting at that time, just seeing what it was like to lay down a board, so we weren't really watching which way we set it down. Good catch though, but not an issue. We will lay the board down in the proper orientation when we actually setup to cut.

We put down packaging tape first, so the grease isn't on the timber. It is working well, we can push the car with one hand and it travels on its own for a few feet, gliding smoothly.

We haven't shown the trailing edge work yet, it is not just foam. That part comes after the rest of the board is shaped. As for the direction of the router cut, we just prefer fixing it in place and moving the sled.