View Full Version : Question for Coguina Builders
09-29-2010, 08:57 PM
I am making snail-like progress on my Coquina build, yet I am moving. I have 22 of the 24 strakes cut, the molds set up on a rolling frame, inner keel (hog, as they call it at Hylan's shop) attached to transom and inner stem, walnut crook milled transom knee attached, as well as the mast step assembled and attached. In short, I believe I am ready to hang the garboards.
In the detailed photos, it appears that they did attach the OUTER KEEL to the inner keel before any planking starts (or milled, rather than attached I guess).My keel is two piece, which is an alternative construction in the plans. I would note here that I am building in ply, and they used primarily a solid wood boat for most of their build pictures. I don't know if that matters, just mentioning it. They also used what appears to be a one-piece beveled keel, rather than an inner and outer, as is specified for the ply build. I know this sounds contradictory, but it looks like they used a solid one piece keel with the solid cedar planking, and there are no photos of how they did the two piece keel, which is the alternative for plywood.
My question: did any of you Coquina builders attach outer keel after the planking? If this were a skiff, I would say that attaching the outer keel--in essence the rub sole--would be best left for the last step.
But if the outer keel is necessary to get out the proper lower plank edge shape, I can see how it might be better to attach that before the garboards.
Anyone have an opinion on the order of attachment?
09-30-2010, 09:27 AM
Dave, You are correct, the outer stem is attached to the inner stem after the planks have been installed and trimmed flush with the inner stem. The outer stem is then spliced on to the keel and glued as a cap over the inner stem. I am finishing up the floor boards (sole) of my plywood lap Coquina. This is a great build! Good luck with yours.
09-30-2010, 07:44 PM
When I made my stem I laminated the outer part over the inner half, with a layer of plastic between them. I also glued the garboards on and planed them to a level faying surface before adding the outer keel. I think this method is shown on one of the construction drawings. (pause...) Yes, it is, on sheet #8, with the offsets for "Keel Layout for Glued Lapstrake Construction".
Dave, if you have their CD of construction photos you'll see they show the building by both glued-lap ply and solid cedar-on-oak methods. John Brooks is the builder in the pictures, and glued-lap is his specialty. He says in his book on the subject that planing the garboards to give a flat surface for the outer keel to land on gives a stronger structure than a rabbeted joint. I think the best time to add the keel is after you have hung 3 or 4 pairs of planks, so that you can still reach the centerline of the boat without stretching. Then you can add the outer stem, scarfing it to the outer keel, after you have completed the planking. That's how I did it, anyway.
The book, How to Build Glued Lapstrake Wooden Boats, by John Brooks and Ruth Ann Hill, is well worth getting for this project. It's full of little nuggets of wisdom.
09-30-2010, 08:00 PM
Photos would of course be hugely appreciated by everyone, I'm sure. It's always nice to have lots of stuff to compare.
10-01-2010, 01:28 AM
Since I posted this, Hylan wrote me a letter and said, to paraphrase, put the hog, transom, transom knees, and inner stem together, then plank. Next, outer stem, with outer keel last. This sequence made the most sense to me (which I compared to skiff construction sequence). I bought the Brooks book last weekend, coincidentally. For some reason I missed the section, or didn't notice, the Hylan manual photos of the ply. It appeared that everything was from the cedar build. No matter: I have the garboard and the number two strakes now hung and rough fitted, but not glued on yet. My plan is to hang one plank, fit it, then rough fit the next, then glue the first set. This might sound laborious, but I am afraid of getting one or two planks way out before I catch it, and then having to re-cut. Thus far I have been stunned by the accuracy of the plans transfer. They have really been on. That doesn't mean I won't screw it up. I am just getting warmed up, but I have at least a case of wine stockpiled.
10-01-2010, 01:38 AM
ash laminated stem. what appears to be a bad fit was actually just one strip that was slightly narrower than its neighbors.
10-01-2010, 01:40 AM
getting the molds on. the transom is laying along the jet.
10-01-2010, 01:44 AM
these photos are about three months old.
10-01-2010, 05:57 AM
Dave, it sounds like you are right at the point where I hit the only snag in the building. As the garboard and the second plank roll from Station 4, through station 2 and land on the stem they do quite a bit of twisting. You want to be sure that they stay tight to station 2 without bending away. I think I let them spring out a bit (~ 1/8") and only discovered the unfairness when I laid plank #3 on the hull. The way I fixed it was to remove the forward half of the first 2 planks and scarf in new sections. The rest of the planking went on without trouble.
10-01-2010, 02:10 PM
ash laminated stem. what appears to be a bad fit was actually just one strip that was slightly narrower than its neighbors.
I would have put that narrow strip on the outside so when you bevel the stem it disappears.
Or put it where the rabbit goes. OR...Put it on the inside because no one will see it in the dark forepeak.
Three ways out of that problem!
10-01-2010, 06:53 PM
That narrow laminate will get planed flush in the beveling. No worries!
10-01-2010, 11:25 PM
Donald: Rob is correct in that the little narrow strip is inconsequential when beveled. Rob: YIKES on having to scarph in a new section. Sheesh. I will double check my fits. I am hoping to have three planks glued all the way around by Sunday. That is a damn troubling development. Will continue to post, if people are interested.
10-02-2010, 07:52 AM
Yeah, Dave, as I said, that was the one snag in building my boat. I realized I had a problem just before Thanksgiving and hemmed and hawed over it until after New Years. My wife and a couple friends advised me not to obsess over it, that it's just a boat, etc, but the shadow of Capt Nat was hanging heavily over me and after the holidays were over I marked out the 4 scarf joints and went at it. And I'm glad I did. That hollow bow is an integral part of the beauty of Coquina's hull and it's worth getting it really right.
10-02-2010, 09:49 AM
Rob: I woke up at 5 this morning worrying about your post. I reread it again, and I think I understand what you are describing. When you say hollow box, in actuality, there is a little reverse hollow just before those two planks hit the stem, right? This would have the effect of being knifelike with little resistance when the boat is heeled while under sail. Therefore, you must have had a bit of outpush with your first effort. Thanks for the info.
I am running into a little hesitation on the next-to-last station before the transom. Either there is a bit of reverse run there (meaning, a break in the boat's rocker towards flat) or I have one mold about 1/4" low. It is not eye sweet, and easy to compensate for--unless NGH wants it that way. Will post a photo of the mold under a batten later this morning.
10-03-2010, 05:57 PM
What did you find, Dave? There shouldn't be any reverse curve in the after end of the boat. The only hollow is in the waterlines forward, approaching the forefoot. I can tell you from experience that it's easier to fix now than it will be any later in the game!
10-03-2010, 10:44 PM
Rob: I tried to photograph the slght dip but it just didn't translate well to the camera. I re-checked the plans and I thinks it is clear that I have one mold slightly low. This means the plank edge hash mark is out by maybe 3/16s. The others are in so I can and did compensate. I have cut my planks slightly oversize for compensation. I now have both garboards fitted, hung and glued permanently. I have the second strakes fitted and hung. Hopefully glue will start tomorrow on the second planks. It feels like now things are starting to move. I spent way too much time on the damn molds and rolling carriage, but we all know that being meticukous at that stage pays off later. So I was super, super careful.
I think I have the right slight hollow at the stem on the garboard. You can just make it out with the naked eye. I haven't sprung a batten on it but it looks right.
10-04-2010, 06:30 PM
Dave, does the "low" mold show a gap under the hog? If it's too low there would be a visible gap in there. Even if you have already glued the garboards on you would be able to shine a light in there and see it. I'm leery of compensating for a misalignment in one dimension by altering something in another dimension. It always seems to bite me on the ass. A photo would help. (You know how photo-challenged I am!) Anyway, on the after half of the hull a batten should lie easily over it along any strake and touch all the molds with no dips or hollows.
Picture a round-shouldered old man with a beard, granny glasses and a snap-brim cap peering over your shoulder... It's the ghost of Capt. Nat! :D
10-05-2010, 02:13 AM
Rob: the gap is about an 1/8" under the hog. This puts the first plank edge hash mark out accordingly. Because all the others are dead on, I think I am OK. In other words, I ignored it, and tapped a nail through the hog just slighty, so maybe I am out 1/16 when all is said and done. The eye can't see it. I am satisfied with it. I finalized fitment on the second planks tonight but could not find time to glue. WIll post some photos later this week. I hope yhou will continue to offer advice; much appreciated. I probably wouldn't have caught that hollow at the second station had you not pointed that out.
11-02-2010, 02:02 AM
It's starting to plank itself. I feel like it is moving now. I still have that damn droop of 1/8" over the slope of that last 24" of planking as they come into the stern. It is barely perceptible, but I know it is there. I have tried wedging (and therefore elevating)planking over the last mold, allowing the second molding position to raise by an 1/8", and increasing the bevel angle of the stern contact. Further, it is only happening on this side. I am sure somthing is out by an imperceptible amount 12' from where the error is--and since error increases over distance, it is popping up right at the transom union. But as they say, No worries--it is cosmetic only and easily faired when I get around to painting.
11-02-2010, 02:03 AM
If you are watching, Rob, I managed to get the hollow box in the first few planks, but now it is really torturing the plank to pull it in to full contact with the last mold. I am starting to ease up on it.
11-02-2010, 02:31 AM
11-02-2010, 04:54 AM
Interesting I found my station 12 was about 1/8" low and put it down to an error when I marked out the mold. I adjusted the mold before fixing the transom to the hog and planking seems to be going OK although it seems the novice builder keeps looking for fairness and starts imagining problems.
With regard to your original post I glued the keel after fitting the garboards then cut the slot in the hog. My thinking this would be easier to do before all the planking goes on. I figure the outer stem can be fitted last and the keel section at the stem can be glued and faired from there.
Looks like you are a plank in front of me.
Good luck with it.
11-02-2010, 12:44 PM
Dave, I believe many of us, perhaps most experienced some hollowness in the forward 24" of planks 3 and 4. It wasn't much, perhaps an 1/8". I used some temporary bracing inside the hull to hold the glued plank out so that a fair joint could glued to the next plank. After about plank 4 everything seemed OK with forward section. The glued laps held the plank seams tight. Good luck, it's great build. - Mick
11-02-2010, 09:12 PM
Dave, your boat looks fine from here!
You're at the stage I was when I added the outer keel to my boat, before it became a stretch to plane the garboards off flush with the inner keel.
When you say "full contact with the last mold", do you mean the one closest to the transom? If so, I would think that fair curves are more critical than tight fits to the mold, since that mold may be a trifle low. So long as the planks come in sweetly to the transom.
11-02-2010, 09:52 PM
One of these days I'll take time to read my posts before I put them up, instead of whipping them off my cell phone while I am sitting waiting for a judge to come at me. Rob, I should have said THE FIRST mold coming into the stem. I think it is eye sweet, and a little tight coming down flush to the mold. My "droop" problem arises from the very last mold before the transom. It is just enough to see daylight through with a 24" straight edge on it. Let's face it, if that is my worst error on this boat, then Hylan has done a fantastic job. So at this point my post should read, "Coquina update" rather than the original questions. I'll start another thread as I have a photo or two coming later. I am six planks all the way around as of today. It's almost halfway--when you consider that shear is going to take some real effort. I might skip the molded part and double up on the strake. The tedium of building the rolling carriage and assembling the molds is well past now: I am at the joyful boat stage. It is just wonderful. Everyday it gets more like NGH's dream (not that I will ever be able to duplicate his yard's work, but you know what I mean...).
11-03-2010, 10:21 PM
Back to your search for photos: I used the Doug Hylan / Maynard Bray CD and I also documented the detailed steps from building my Coquina on my site. I hope you like it, and that it is helpful.
I attached the outer stem after planking.
Let's stay in touch.
11-04-2010, 12:35 AM
Thank you Breeze. You may recall that I was especially impressed with your documentation of your build--the build photos looked like a professional photographer did them. I will continue to post as I stagger forward on this, both for my own edification and the amusement of others.
11-04-2010, 12:41 AM
Here is a photo of a paid actor reenacting cutting bevels by wrack of eye with a handsaw. It is something I remember reading by Tag Freid on furniture building, I can't recall what he was using it for, but I can get better bevels this way than with a beveling gauge. The saw blade(which incidentally is turned teeth up) acts like a batten. Of course, I still dry fit the plank before I do anything drastic--I have been getting them dead on so far.
No drunks were harmed in the making of this photograph.
11-06-2010, 05:43 PM
That paid actor looks a little small for a full grown man, you need a standard reference for size in there so we can know for sure:D
11-07-2010, 01:07 AM
That's actually an eight foot saw.
11-08-2010, 08:19 PM
I try to read every word and study every photo. I can only imagine how instructive it would be to perform an exhaustive evaluation of your wine, while sitting back in a chair at your shop watching the progress. Thanks for taking the time to post photos.
11-09-2010, 12:50 PM
Yes. It is instructive to watch what to avoid.
11-09-2010, 07:43 PM
Certainly a design on my short list. After I finish the Redbird canoe as well as start and finish my catspaw........ then maybe Coquina?
11-09-2010, 10:19 PM
Ain't it the truth, brother. I am thinking I am going to start on a Fiddlehead around the time I get this hull turned, and it might be as early as Thanksgiving. The thing is, I think it would be interesting to stretch the Fiddlehead to 15ish and row it. It's such a good looking hull, and only three strakes. I should be able to build that in three days, right? You know, IF EVERYTHING GOES WELL.
11-10-2010, 10:47 AM
Though a catspaw is a great boat, I'd skip it and go all out for the Coquina.
You won't regret.
Keep us posted...
11-10-2010, 11:00 AM
I love both. The issue is that the catspaw has a designated duty. I need a tender that can be hoisted up into the stern davits of the yet to be built yacht I will cruise in upon retirement. She's also a go at practicing some skills that will be needed to build said yacht. Guess I'll have to have them both. To me boatbuilding is more a means to an end than many others. Don't get me wrong, I thoroughly enjoy the construction, satisfaction and oos and aaahhs from onlookers when using the craft but I want a boat that is out of my means. The only way to afford her is to build her and take a bit of time doing it. My mortgage plan if you will. No, looks like I'll be "stuck" building more than one boat. :D
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