Drawing out the next major Zip part

At first glance, the Zip has some rather odd frame designations.... Specifically, frame number "5-1/2".

It seems odd until you understand that the designations are logically based on boat design drawings. If you look at a cross-section drawing of the boat, there are several vertical lines that divide the hull into sub-sections. Each one of these vertical lines is called a "station." The numbering starts at zero (the transom), and ends at "F.P." (which stands for "Forward Perpendicular") at the foremost tip of the boat. In the case of the Zip, there are 8 stations including "F.P.", dividing the hull into 7 sub-sections of about 24-1/2" each. Frame # "5-1/2" is the frame placed between stations 5 and 6. It is located near the base of the stem.

Frame number 5-1/2 is a very important part. As the instructions indicate, the horizontal line formed by the floor member of frame # 5-1/2 is the plane from which the rest of the boat is set up. The instructions specifically state to take extra care to ensure that this part is accurately measured and constructed.

I just finished drawing this part, and I thought it would make a good blog post to illustrate how the Glen-L plans are copied to the wood.

First of all, you fold the carbon paper in half, so that the lines you trace through it are transferred to both the wood AND the back of the actual plans. Then you place the plans on the wood, and flatten them down securely. Push pins help for this.

Secondly, trace the plans for the part you want to build. As I mentioned in an earlier post, the centerline is THE crucial reference point for the boat. ALWAYS carefully draw the centerline. Make sure you extend your traced centerline beyond the needed dimensions of the part, for this reason:

Third, draw "sight holes" that are centered on the extended part of the traced centerline. I like to trace a small coin for this purpose. Use an exacto knife to cut your sight holes through the paper. Youll need these holes to align the plans after you flip them over.

Here Ive traced out the floor timber, and have cut sight holes on the centerline.

Next, remove your push pins, plans, and carbon paper from the wood. The half-width of your part should be clearly visible.

Half-width of the floor timber drawn onto 3/4" Douglas Fir marine plywood.

Now, un-fold the carbon paper, and place it normally onto the wood where the second half of your part is to be drawn. Flip the plans over, and youll see the carbon-copy you made on the back of the plans. Carefully and accurately align the sight holes on the extended centerline that is traced onto the wood. Again flatten the paper down securely. Now youre ready to trace the second half.

Plans flipped & aligned. Ready to draw the second half of the floor timber.

Trace the carbon-copied lines onto the wood, just like you did the first side. When youre done, the full part will be drawn onto the wood.

The full floor timber drawn onto the wood, waiting to be cut out.

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The Utility part 2 The Keel

The Utilitys keel is made from a 1" x 3" x 8 board, laminated on the inner surface with an additional 1/4" x 3" x 8 plywood backing piece. Optionally, the builder can substitute a 1-1/4" thick solid board. I chose the standard laminating method.

This is where I ran into a little trouble. 

Firstly, I had cut the frame notches as precisely as possible, as-drawn on the plans. For the keel notch, it was 1-1/4" deep. 

Secondly, the "1-inch" mahogany board Id bought for the keel was in fact only 3/4" thick. (I touched on this in my last post.) So, after laminating on the 1/4" plywood keel backing, the keel was at this point only 1" thick overall.

I briefly considered scrapping the keel and buying a full 1-inch mahogany board to re-build it. The problem there is that mahogany is quite expensive. Also, as youll read in other boatbuilding blogs (and certainly this one), problems arise. Its a given. If you re-start every time a problem arises, it will take you forever to get the boat built. What Ive found is that boat construction, particularly for the first-time builder, involves a lot of troubleshooting. Frankly, thats part of the fun. At least, I think so.

I decided to simply add a second lamination of plywood in order to make up the needed thickness to match the 1-1/4" notch. I did still have some left-over 1/4" marine plywood, but not enough to cut a full 8 length. So, I decided to try my hand at a scarf joint.

Instructions for making scarf joints were included in the plans. Basically, to scarf two sections of 1/4" material, you bevel the ends of each piece along a 3" span. Then, you flip one piece over, fit one diagonal bevel over the other, and glue the two together with epoxy. Creating the bevel is probably best done with a plane, but I didnt have one at the time. So, I used a small Black and Decker sander.

Scarf joint before being glued.

Scarf joint after gluing.

I glued the scarf joint together and added the second keel backing with Poxy-Shield thickened with #2 Silica. The end result wasnt exactly pretty, but it was functional and felt very solid along the full length of the keel.

As with the Squirt, the Utilitys transom is raked backward at a 12 degree angle. Notches in the transom frame members must be cut before fastening all the transom parts together. This is because the keel and floor battens do not pass through the transom. Instead, they butt up against the transom. Ideally, the transom frame notches should be cut in such a way so as to match the fitted angle of the transom.

I did not do this. Instead, I simply made perpendicular cuts into the transom frame members. As a result, when the assembled transom was fitted to the construction form, my notches turned "downward" 12 degrees. This meant that for proper fitting, I would need to bevel the ends of the keel and floor battens. I did this using a circular mitre saw cutting on a bias, in addition to using a rasp, file and sander.

In the end, it worked out fine. However, Id recommend cutting the frame notches at an angle if possible. I believe the final joint would be stronger.

Aft end of keel after beveling.

Beveled keel fit into its transom frame notch.

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Fairing day part 1

today, I sanded away all the high spots on the seams, and shaped the centerboard trunk slot using a router, and 7" disc grinder (aka wood eraser).  My arms are sore, but things are relatively fair.  I will need to order the fiberglass this week.   The plan is to use wide 6 oz cloth cut on a 45 degree bias, then apply 6 oz cloth over the whole hull.  This will be a long and tedious, messy task but will add value and years to the boat as well as much needed protection from rocky beaches.  I will put the keel on afterwards.

the PVC roller system is working very well to get this in and out.  

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The Utility part 3 Stem and floor battens

The Utility’s stem, as with the Squirt, Zip, and I assume several other Glen-L designs, is made of 2 laminations of 3/4” plywood. Fortunately, I had enough 3/4” marine-grade Douglas Fir plywood left over from Lusitania 13’s second transom to build both the transom and the stem for the Utility. 

The laminations are glued together with marine epoxy, (I used Poxy-Shield thickened with #2 silica), and bronze screws. The breasthook is basically made the same way, although the mating pieces are shaped differently: The top piece fits over the stem, and the bottom supporting piece fits around the stem. The breasthook is then epoxied onto the stem. I clearly marked all my centerlines, and tried to make the pieces fit as precisely as possible.

With the centerline on the keel clearly marked, I clamped the Utility’s stem/breasthook assembly into position. Next, using twine and a plumb bob, I worked carefully to make sure the whole assembly was aligned with the centerline of the keel. As a one-person job, this is rather tricky. If you have someone to help, it should be much easier.

With the assembly clamped into position, I drilled two 1/4” holes vertically through the forward part of the keel and aft section of the stem, countersinking the carriage bolts. After applying copious amounts of thickened epoxy, I bolted the stem to the keel with 5” long, 1/4” bronze carriage bolts. After tightening them, I filled the extra space from the countersunk carriage bolts with thickened epoxy.

Stem clamped and bolted onto forward end of keel.

Stem-to-keel joint after epoxy. Glue blocks added for reinforcement.

Having now learned my lesson from having to build up the keel thickness, I turned to the floor battens. As I mentioned before, the frame notches for these were cut to 1” deep. “1-inch” lumber off-the-shelf is typically only 3/4” thick. So, for the floor battens, I purchased an 8-foot, “5/4” mahogany board. (After they plane 1/4” off it at the lumber yard, you’re left with an actual 1-inch thick board.) The cuts for the floor battens were straight cuts, producing four 2” wide battens. Cutting the battens produces a lot, I mean a lot, of red sawdust. I decided to sweep up & collect most of it to use as wood flour to thicken epoxy later on. This turned out to work quite well.

The floor battens had to be fitted into the transom frame notches the same as the keel. The battens were fastened on with thickened epoxy and 2” bronze screws.

Transom knees attached to keel & transom. I put these on before adding the floor battens.

A note about bronze screws

Bronze screw heads are rather soft, and will strip out on you easily. This is particularly true when using a power drill as a screwdriver. Below is the method I used to remove a stripped screw during the fitting process for the floor battens:

Totally stripped-out bronze screw head.

I cut a slot in it with my Dremel.

Removal was then easy with a flat-head screwdriver.

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The Utility part 6 Fixing the chines

I made a common mistake when I installed the chines. Sure, Id read about the possibility of making this mistake beforehand. However, I obviously didnt "get" it. Happily, its a common mistake with a fairly simple fix. Im going to share all this with you in hopes that the new builder might avoid this pitfall.

The mistake is: not getting enough twist in the forward section of the chine log.

The resulting problem is: inadequate twist in the forward section of the chine leaves you with NO SURFACE AREA for the side planking to mate to.

Heres an image to help illustrate:

You see, after the chine and sheers are installed, both of these pieces are faired. The forward section of the chine is basically beveled along a line running down the middle of the wood from the stem to the forward frame. The upper (top-side) section of this bevel is where the lower edge of the side planking will attach. The top-side edge of the planking will attach to the sheer (shown as the dashed white line in the photo).

If you do not put an adequate twist in the forward section of the chine, then the resulting angle will not point outward adequately to the sheer line. This problem is illustrated by the dashed red line in the photo.

To avoid this problem, be sure to twist the chine adequately in the direction shown by the green arrows before you permanently attach the chine to the stem & frames. I did not twist mine adequately, because I thought the wood was going to break. So what. Soak it, steam it.... whatever you have to do to make it twist enough. Otherwise, youre going to have a problem to fix — just like I did.

The Fix:

The fix is: add a wedge-shaped strip along the top-side half of the forward chine, so that youll have an adequate angle toward the sheer & enough surface area to attach the planking to after fairing.

The Utilitys chines are 2 inches wide. The distance from the tip of the stem to the forward frame is 4 feet. So, I ripped two 1-inch by 4-foot sections of wood from the remnants of my first chine log (which broke because I didnt steam it).

I placed a straight edge from the chine to the sheer, and measured the angle. I then beveled my new "chine strips" so they would angle 20 degrees outward from the surface of the installed chine log. The resulting strips were fairly thin.

Cross-section of the "chine strip" after beveling it 20° on a planer / jointer.

I then epoxied these strips onto the top-side half of the forward chine. They were a little long, so I had to trim them. They bent easily since they were so thin. Now, I should have an adequate surface area for fairing & attaching the side planking.

Forward end of the attached chine strip, trimmed along bow line.

Aft end of the chine strip at the forward frame. This will have to be beveled down to make a fair curve along with the rest of the chine log.

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Unangax Aleut Kayak Terms Part 0

A few decades back, Knut Bergsland, wrote an article called Aleut Kayak Terms which was published in Contributions to Kayak Studies in 1992. The article contains a wealth of information but in a format that is difficult to extract information from.  The article has a few illustrations that tie Unangax^ names directly to kayak parts and parts of hunting implements, but for the most part, illustrations are lacking and we have to wade through Bergslands difficult syntax to figure out whats what.

Sample page of  Bergslands prose.  Click on image for readable size illustration.

So for some time, I have been wanting to draw some pictures of the things that Bergsland was supplying names for so that someone wanting to know what the Unangan called their kayak parts and activities related to kayaking would have an illustrated guide, myself being the primary audience.
As it turned out, the project was always in progress and never made much headway, primarily because I didnt  give it the time it needed and because I didnt think there was enough of an audience besides myself to justify the effort.  After all,  the information was there in Bergslands article, even if difficult to extract.

Sample of kayak drawings I made to anchor Unangax^ kayak terms to. What would be helpful would be English names for the kayak parts and the transliterations that Bergsland gave where the Unangax^ names were descriptive, for instance, deckbeam for kicking your feet against.  

But the other day I was for some reason inspired again to work on this project and thought that if I approached it piecemeal and posted my illustrations with Unangax^ names attached as I completed them, they would be available even if I never finished the thing as a whole.
Some Background
Unangam Tunuu, the Aleut language, had several dialects so that there might be different names for the same kayak part depending on the dialect.  Also, names varied over time and from village to village even within the same dialect.  Bergsland records these variations to the extent that they made it into print.
Bergsland distinguishes between several dialects, which he calls Eastern Aleut (EA), Atkan Aleut (AA) and Attuan Aleut (AU).  Within the article itself, he uses only the abbreviations.  Where Unangax^ kayak terms are similar to Yupik, Bergsland also lists them, primarily as he explains that this indicates antiquity, given that Eskimo an Aleut languages diverged quite some time ago.
Stay tuned.  More of this sort of stuff may be forthcoming.

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The Utility part 1 Getting started

The Glen-L Utility is a simple but classic 1950s utility / fishing boat. It is 11 LOA, with a 5 beam, wood foredeck, open cockpit, and simple thwart / bench seats. Specs say it can carry up to 3 average passengers. Most of the photos Ive seen of them show basic tiller outboard steering. I got my plans around early April of 2012 & got started immediately.

Having learned my lesson about asymmetry in the construction of the frames, I approached the Utilitys frames very differently. First, I drew out frames 1 and 2, as well as the keel  backing, full-size on a sheet of 1/4" marine-grade Douglas Fir plywood.

Frames & keel backing traced out on the plywood.

Then, I traced all the frame members from the plans directly onto some 3/4" mahogany, and cut them out with much more care and attention to detail than I did with the Squirt. 

I learned an interesting thing about mahogany. Apparently, it is rather light sensitive. Driving home from the lumber yard, a small portion of the board was sticking out my back window. After about 2 hours in the sun, that part had turned considerably darker, as seen on the keel in the photo below.

Keel and frame members laid out on the plywood.

In order to maintain the best possible shape and alignment of my frames, I then epoxied the frame members directly onto the plywood. I later used the scrap from the cut-out portions of the plywood to make my remaining frame gussets.

I fastened the gussets onto the frames using Glen-L Poxy Shield epoxy, (thickened with #2 silica filler), and 1-1/4" bronze screws. The frames & interior surfaces of the transom were encapsulated with 3 layers of Poxy Shield. After each layer dried, I scrubbed & washed off the amine blush using dish detergent, warm water & a Scotch Brite pad. I also sanded lightly between the layers with 220 grit sandpaper.

Gluing the forward frame members onto the plywood.

The frame notches in the plans are 1" deep (other than the keel notch, which is 1-1/4"). Most stock sold as 1" these days is actually 3/4". If I were doing this again, I would probably change the notches to 3/4" in order to use some less expensive & more available boards.

Another thing I did differently than with the Squirt was to take construction of my building form much more seriously. I made it from 2x8s and 2x6s, with well-reinforced cross braces made from 2x4s left over from the Squirt form. I took a lot of care to make sure the surfaces were level, clamping them into position before fastening with 3" wood screws. Trying to build something with level surfaces on a sloped floor was a little tricky. The key is to mark the positions of the legs on the floor once youve gotten the parts level. That is, unless youre going to bolt the form to the concrete floor. Thats the preferred method, but several builders dont do that. I didnt.

Frames, transom and keel on the building form.

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The Utility part 5 The Sheers

June is upon us, and with it my daughters birthday, as well as the arrival of the stifling summer heat and humidity were "blessed" with here in the south. Ah well... Every day above ground is a good day, and this day is off to a great start.

It was a beautiful, clear morning as I drove on traffic-less back roads, listening to Aaron Copelands Third Symphony (possibly the greatest piece of American music) on the radio. Passing a faded American flag, backlit by the early morning sun, I thought of my grandfather and the hardships he endured during the 1940s... and of how, with the nightmare of the war behind him, he used to drool over 1950s Chris-Crafts at a local boat dealer. I only learned about that recently, along with the fact that hed contemplated building his own boat.

But, Im digressing.

The Sheers:

"Youll never have enough clamps." Start building a boat, and youre going to hear this early-on from other boatbuilders. By the time you get to installing your sheer clamps, youre going to need them. (I wonder if thats why theyre called sheer "clamps"?)

Sheer clamps, also frequently referred to as "sheers," are the long boards that form the top rim of the sides of the boat. They extend from the outer corners of the transom, and meet at the stem, forming the pointed bow of the boat.

In any case, the Irwin "Quick Grip" bar clamps youll see a lot of in my photos are great all-around clamps. They arent perfect, however, nor are they indestructible. Although I had many 6" and 12" sizes of them by the time I was ready to install my sheers, I still needed to get larger 24" clamps of both the Quick Grip and standard bar clamp varieties. The 24" Quick Grip clamps were perfect for holding the sheers upward into position. But, this style of clamp just couldnt complete the bend of the sheers up forward. For this, the standard bar clamps do a much better job.

Sheer clamp notch in the transom frame. This shallow notch would later pose its own challenge.

A 24" Quick Grip clamp (back) holds the sheer upward into position. A 6" clamp (front) is being used as a lever to twist the sheer into the required vertical orientation.

A 24" standard bar clamp holds the forward tip of the sheer into its fully-curved position against the breasthook and stem.

The stock for the sheer clamps themselves was again Southern Yellow Pine, as with the chine logs. This was for the same reasons of the wood being both inexpensive and easy to bend. The sheers are built from two layers of 1-1/4" x 5/8" x 12 material. I ripped the 4 strips from a 12 "1x6" board from Lowes that had fairly vertical grain. Of course, a so-called "1x6" is in reality only 3/4" thick. I planed the 4 pieces down from 3/4" to 5/8" using a small planer/jointer my dad bought from Harbor Freight. In retrospect, I probably shouldve planed down the board first, then ripped the 4 pieces.

Overall fitting of the sheers was easier than the chines. The bevel in the forward frame notch was milder for the sheer than was needed for the chines. Unlike the chine, which twists as it bends, the sheer is supposed to remain in a vertical orientation.

Prior to bending the sheers fully, I wrapped towels around the wood and poured boiling water on them, then let them soak a while. After doing this a couple of times over the course of a couple of hours, the sheers bent easily into place. I measured the angle at the junction of the breasthook and stem, and used this as a guide to cut the forward tip of the sheers. After some additional fitting, I clamped the sheers into place and let them sit overnight. Later, I drilled holes & screwed them into position at the breasthook, frame #2, and frame #1.

I could not determine a way to drive screws through the sheer and into the transom frame, however. This was due to the shallow nature of the transom frames sheer notch. Rather than drive a screw through the back of the transom and into the end grain of the sheer, I decided to simply let the epoxy hold it for the time being.

The instructions state that you need to drive screws through both sheer layers & into the frames. However, I did not see a way to hold the sheer into place long enough to let the epoxy dry without driving screws into the frames. This was particularly the case because I had to force the sheers into a vertical orientation by using bar clamps as levers, as shown above.

Once the first sheer layer had been fitted, it was time to disassemble, add thickened epoxy, and re-assemble. I used System Three Gel Magic, thickened with mahogany sawdust. I attached the sheers at the breasthook and frame #2 first. Then later, after the epoxy cured at those joints, I finished the aft section.

Forward tip of starboard sheer (layer 1) attached.

Forward tip of port sheer (layer 1) attached.

After the first layer was on, I sanded it in preparation for adding the second layer. Fitting the second layer was easier, since it basically just had to lay on top of the first. This is where you need a lot of clamps!

Soaking the forward end of sheer layer #2.

Starboard sheer layer 2 bent & fitted into position.

2" silicon bronze screws were staggered between those used to attach layer #1.

Disassembled & ready for epoxy.

Waiting for the epoxy to cure. I used Glen-L Poxy Shield thickened with #2 silica and mahogany sawdust.

Et voilà!

Since layer 1 was screwed directly to the frames, I drove 1-1/4" silicon bronze screws through both sheer layers on either side of each frame. I hope I countersunk these adequately for fairing.

Repeat for the port side.

Both layers on & laminated!

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This Old Kayak Old Paint Part 1

People occasionally write me to ask whether they can use this or that material or process in the building of their boat.  I sometimes have answers for them and more often do not.  When I dont, I like to tell them to try whatever it is they are asking about and they will find out if it works or not and then they will be the experts on that particular topic.
In any case, I try a lot of stuff, more or less indifferent that a lot of it wont work.  I also am casual about boat storage so most of my boats are subject to accelerated aging. I also like to use off the shelf, not yacht approved materials to see whether there is a cheap way out of any particular conundrum.
So lets move on to todays topic, Old Paint. No not the horse.  Old paint that has turned dry and brittle and stressed and developed cracks.  To be more specific, old varnish.  Because the substrate of the varnish on a skin on frame boat is a flexible fabric, impact on the skin causes fractures in an interesting way. So proceed and feast your eyes on a variety of stress cracks in old varnish on a nylon skin.  Enjoy.

A small running critter.  The green flecks are fake gold leaf I put in the varnish.  The gold is actually brass and has oxidized to a green.

stretch marks.

Southwestern US petroglyph, what of, Im not sure.

and a braid.

More stretch marks.

This one kind of looks like an ancient shrimp fossil.

This one, Im not sure, kind of like a cartoon bird in flight.

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