14 May 2013

When You're Ready...

Something happened to me a few weeks ago. After months and years of thinking and plotting and planning and drawing and worrying about how to build a decent galley into the Blue Moon, I suddenly realized I knew how to do it. Not that I knew exactly how to do it, but I had enough confidence to know I could probably figure it out if I dove head first into the process.

This confidence is what I needed to rip out the 'galley' that had served its purpose (however poorly) during my long voyage up the east side of the US. This so-called galley was nothing more than a lightly-built cabinet with three flimsy shelves, with a single-burner gimbaled stove screwed onto the side. I was never happy with it, and while ripping it out, I realized that it probably wasn't built by the original builder of the Blue Moon, who was a very good builder, and quite neat and tidy with epoxy. This tiny cedar cabinet was cemented to the side of the Blue Moon with great sloppy goops of epoxy that I still haven't chiseled off completely. So I must say I took great satisfaction in demolishing the blasted thing, and chucking the pieces into Cabin Boy for disposal. 

Then it was time to start building.

The replacement galley will be the same width, but about twice as deep and 10 times more useful, I hope. It will have a large countertop, unbroken by any sinks or stoves. While planning my galley, I read an old book that claimed that a small boat doesn't have room for built-in sinks or stoves, and it was right. When I want to cook, I will put my stove on the counter top. When I want to wash up, I'll stow the stove away, and replace it with a nice plastic dish pan. When I'm not thinking about food, it will be a handy place to examine charts, or assemble small machines, or work on my stamp collection. 

I'm still not certain what will go below the top shelf, but there will be some sort of storage. Exactly what, I will decide after the sides and top are in position. No need to rush these decisions...

The sides will be made from 3/4" exterior grade plywood. Actually, MDO, which is exterior ply with two good surfaces. The forward one will support the head of the new bunk I plan to build, but more on that later. 

The first step was to make patterns for the two half-bulkheads that will frame the galley. To make these patterns, I used a tick-stick -- one of my favorite boat building tricks. 

A tick-stick is a long stick, sharpened at one end, with several notches cut into one side, labeled 1,2,3 or A,B,C, or whatever you fancy. The notches should be close enough together so that whenever you lay the stick alongside the board, one of the notches is on the board. 

To use it, you just put the pointy end of the stick somewhere on the hull, or deck, or whereever the bulkhead needs to fit against, hold the stick securely on the board (I only used a clamp so I could take the photo), and draw a line along the stick, being sure to dip your pencil into the notch.


Tick-stick and board in use on the site of the old 'galley'.
The wet-looking spot is actually dish detergent that spilled in the cabinet
years ago. Why it left such a stain, I do not know...
The board is equally important. I built mine so the front edge (the one to the left) is straight. It represents the edge of the bulkhead. I positioned the board so this edge was exactly where I wanted the front of the bulkhead to be. I used a quality bubble level (on a calm day!) to make sure the front of the board was exactly vertical. 

The pointy end is also important. You want to position the point so it sits exactly on the hull where the corner of the bulkhead will go. The angle just has to be small enough so the point can sit on the hull without the right side of the board interfering with the hull. The board needs to be wide enough to capture the measurements. A foot is wide enough.
 
If you click on the photo below, you will see a bigger version of the image. You will see that I have already captured the profile of the underside of the deck, where the deck meets the cabin top, the corner where the deck meets the hull, and several other important structural detail. Note that each line has at least one notch on it, and that the notch is labeled 1, 2, 3, or 4.  These correspond to the 4 notches on my stick. You might need fewer or more notches, but 4 worked for me.

Note also that I labeled the various lines to make it a bit easier to reproduce the shape I'd captured later.

Close up of details

Here's another shot that clearly shows the 4 notches.

Another angle showing the various ticks

When you are done, you'll have something like the photo below. The more measurements you take, the better -- up to a point. You don't need a million measurements -- just enough to capture all the important corners and curves. 


The board when done. Notice labels! Very helpful.

When I finished with the first half-bulkhead, I did the other. The process was the same, of course.

Once I had my two sets of measurements (made on two different boards, but with the same tick-strip), I brought them back to the shop to reverse the process. 

The first step is to line up the straight edge of the board with one of the machine-cut edges of the plywood. This straight edge will be the front of the bulkhead.

Then all you do is pick one of the lines you drew on the board and line up the tick strip, being careful to position the correct notch on the stick with the labeled notch on the board. When the stick is carefully lined up, clamp it firmly, then go down to the pointy edge of the stick, and draw a dot right under the point. 

Repeat for all the lines on your board. 

Reversing the process onto pattern stock
When I was done, I had a bunch of dots that represented the shape of the hull, and several more that showed where the flat underside of the deck was, and the two corners where the deck met the hull, and where it met the cabin top.

I used a light mahogany batten to connect the hull dots. This is just like spiling a pattern when building a boat. The dots almost lined up perfectly, but the purpose of a batten is to make the imperfect measurements into a perfect curve. The batten evens out the mistakes. More or less.

Connect the dots with a batten
The curve is the hard part. You can use a straight edge to connect the deck-line dots. 

I'm always torn about how to cut such a large, curved design from a piece of plywood. I used my go-to tool for this: a jig saw. There might be a better way to do this, but I'll be darned if I know what it is. For now, a jig saw works 'good enough', if  you are very careful.

If you do everything right, a beautiful woman will agree to hold your lovely work up to be photographed and generally oooh-ed and ahhh-ed over. The Blue Moon's shapely hull is clearly reflected in the hull line. The straight deck line is between Helena's two hands. The straight forward edge of the bulkhead is to the left. 

Have beautiful woman hold up your work.
Here are the two patterns laid on top of each other, with their straight edges lined up. You can see that the Blue Moon changes shape slightly even in the 2 feet that separates these two bulkheads.


Do it again for the other side of the galley...
Notice they are not QUITE the same...
Then it was time for the first fitting. If you did everything correctly, the pattern should fit perfectly. Or at least perfectly enough. I brought a small block plane with me to take a few shavings here and there off the edge. A few test fittings and a few shaves had the bulkhead pattern fitting pretty darn well. 

Before cutting real plywood, check for fit.
(Not bad, eh?!?)
I also brought a saw with me to roughly cut out the top rail of the bulkhead. The side of the bulkhead will be 6" above the counter top. The corners will actually be rounded, but I just wanted to capture the rough shape in the pattern. I'd clean it up in the shop, later on, and duplicate the cuts on the other pattern. 

Make sure the fronts line up!
Again, not too bad, for the first time!
Finally, I took the photo above to show how the two front edges should line up with each other. By 'front' I mean the left edges. Note how you can see both edges, one behind the other, and that they are parallel to each other. 

I would call that 'good enough'.

With the patterns made and fitted, it was time to cut real plywood...


Next Episode: When You're Ready

26 April 2013

Water Line

After giving Cabin Boy's bottom and topsides 3 coats of oil-based white paint, it was time to tackle the last big project on the refit: applying bottom paint. I never got around to anti-fouling his bottom on my trip up the coast. This wasn't too bad a problem, mainly because we kept moving, and because I had time to pull him out and give him a good scrubbing any time the weeds got too thick. But this summer, good old Cabin Boy will be parked on a dinghy dock and will need some protection.

One problem: I had no waterline to draw to. How to paint one on a curving, lapstrake hull?

At one time, in the misty days of my youth, I might have been tempted to do something creative, like perhaps use a plastic hose filled with colored liquid to establish a waterline. It makes sense, right? If you take a long hose and attach it to bow and stern, and then fill hose so the water level comes right up to the waterline at both ends, then if you move one end around the boat, the water level should stay constant and show you exactly where the water line should be, right?

How Not To Draw A Waterline
Ha-ha-ha! Only a pathetically naive boatbuilder would try something like that. A more mature and experienced one would never waste half-a-day trying to get such a crazy scheme to work. No, he'd pull out his books before he pulled out half his hair, and look up the correct, proven, traditional way to tackle the job.

Naturally, that's what I did. (Helena, I told you to destroy those photos!!!)

Yes, the correct way to do this is illustrated in the photo below.  The two cross beams are level with the design LWL (load water line), fore and aft, as shown on the original plans. The cross beams (and the boat) are leveled using a bubble level.

Then a string is hung between the two beams. The ends of the string are weighted, in this case with two big shackles. If the two beams are at the LWL, then the straight line of the string is also at the LWL.

Move the two ends of the string so the string just touches the boat at one end. I stared in the stern. Draw a line under the string.

Then move the string so it bears on the next part of the hull, and continue drawing the line.

Drawing LWL -- actually, an inch above the waterline
Eventually, you will work your way around to the bow. Cabin Boy is a bit hollow in the bow, so you can't get the string to lie right on the hull in the bow, but it is easy enough to eye-ball the line and draw it in under the string.

Move string to hit different parts of boat... draw line under string
Once the line is penciled in, its time to tape. Because the waterline goes onto the second lap in the middle of the boat, you have to be pretty darn neat with your tape.

Tape showing line
After drawing and taping the waterline on the other side of the boat, you are ready to paint. I put on 3 coats of good bottom paint: Micron CSC. A quart was good for 3 coats.

Voila... 
The result? A fairly neat job, if I do say so myself.

Another look
Once the paint was dry, it was time to install the varnished inwales and outwales, cut ropes for the fenders, and otherwise prepare for launching.

Here he is on the town dock, ready to be officially re-splashed. A suitably-beautiful spring day was ordered up for the occasion.

Ready for launching
Looking pretty good...

Don't ask me why oarlocks are like that
After a lovely row across a very chilly Huntington Harbor, Cabin Boy was at last tied up in his summer berth... the dingy dock at the Ketewomoke Yacht Club.

If the club had a contest for best looking dinghy, I'm pretty sure he'd win.

On the Ketewomoke dingy dock

And that is the end of Cabin Boy's refit story. A long way from how he looked after his Big Adventure:

The day after sailing into Huntington Harbor


AFTER having his bottom scrubbed!

Next time, we turn to the Blue Moon's new galley...

Next Episode: When You're Ready

23 April 2013

Leathering Oars

And then, all of a sudden, it was spring.

If winter is too short for boat builders, then the arrival of spring is The Deadline That Can't Be Ignored.

There was the Blue Moon's mooring to prepare: give mooring ball a fresh coat of bottom paint, touch up the numbers, overhaul the pennants, try to figure out why my pick-up stick gives me fiberglass splinters, etc., etc.

Then Cabin Boy had to be launched so he could help out in moving the Blue Moon from her winter berth in the town marina to her summer mooring. That meant finishing up his refit, finishing his oars, figuring out how to protect him in the scrum at the dingy dock, etc., etc.

Then I had to put the Blue Moon out on her mooring. That meant paying a ransom to get her engine released from the mechanic, installing the engine on the boat, remembering where I'd put the kill cord so I could easily find it in the spring, etc., etc.

With a new iPhone project to work on (to pay the bills) and my book to finish, grandkids to visit and children getting jobs and graduating college, there's just been no time to blog. I'd skip to my current project (building a real galley in the Blue Moon), but there were a number of interesting things I wanted to at least touch on before moving on. So this week I'm going to try to catch up with a number of brief posts.

I bought Cabin Boy's oars from one of the bigger marine mail order houses. They are strictly okay. They did the job, but eventually I would like to make a set of real Pete Culler-style oars. But until that happy day comes, I needed to fix these up a bit.

I re-varnished them a year or two ago, but did not want to use them again until I'd had a chance to leather them.

I started with a fairly nice bit of leather that I bought at the Mystic Wooden Boat Show last year. The first step was to cut a piece of the right size. For length, I used the whole length of the piece of leather. Longer is better.

For width, you want the piece of leather to be about 1/4" less than the circumference of the oar handle. In other words, when  you cut out the piece and wrap it around the oar, there should be a small gap between the ends, so you can lace it tight without bunching up.

In the photo below, you can see the tick-strip laid on the piece of leather.

Use tick strip to measure width of leather
Once the piece is cut out, you need to punch holes for the 'laces'. There's really only one way to do this: buy a leather punch. You might be able to do it with a nail and a block of wood, but the leather punch makes the whole process (pun intended) much easier. You need a lot of holes.

The holes need to be approximately 3/16" from the edge, and about 3/8" apart. You need the same number of holes on both sides, and they should line up fairly closely. Think laces on shoes.

Holes punched on each side
Once you have the holes punched, you need the laces. I happened to have a role of tarred marline (tarred nylon). When I bought this a couple years ago, someone said, "Buy a 1 pound roll. It'll be a lifetime supply!"

Not! Tarred marline is incredibly useful. If it lasts me through the next two years I'll be pleased (and buy another roll.) It's perfect for this application. The nylon string is very strong, and the tar just makes it easy to use. When you tie a not in tarred nylon, it stays tied. When you pull the laces tight on the leather, the slight stickiness of the tar helps keep it from slipping. Again, you could use other types of light line, but why would you want to?

It helps if you can clamp the oar in the right position for lacing. Inconveniently, this is with the blade on edge, so you can't just lay the oar on your work table. I padded a vice with an extra piece of leather, and clamped the blade vertically in the vice. For ordinary, symmetric oars, it doesn't matter which edge is up, but if you have fancy curved oars, the top edge of the blade must be UP.

Position the leather on the oar so the middle of the leather is about where your oarlocks will be. Wrap the leather around the oar so that the seam will be at the top -- in line with the top edge of the blade.  The idea is, when you are rowing, the seam should be up so the lacing doesn't chafe on the oarlock. Secure the leather in position with something. I used wire ties.

Cut a long piece of tarred marline. You need a lot, and it's hard to estimate how much so use twice as much as you think you need. 6-feet minimum. The first time I tried this, I got 3/4 the way done and realized my laces were too short. The second time I used 10-feet.

When you've cut your marline, thread each end onto a large sail needle. You will need two big needles because the marline is fairly thick. The needles make it possible to thread the marline through the holes. Don't even try to do this without needles.

Start like you are going to put laces on your shoes. Thread the marline through the first two holes and even up the ends. At this point, it should look like the photo below:

Leather secured in the right position. Needles on marline.
Marline threaded through first two holes.
Next, start lacing, just as you would lace your shoes. You want to pull the marline tight with each pass, but not so tight that you tear the leather. The leather is pretty tough, though, so you can really sung it up. The leather will stretch a bit as you go along.

I don't think it matters much how you do the lacing, as long as you are consistent with each course of lacing. If each course is the same, the finished lace will look much better than if it's laced every which way. If you make a mistake, you'll see it immediately.  Probably. No matter. Its easy to unlace back to your mistake, and try again. Ask me how I know this. You will probably have to remove the needles for this, which is a real pain, so focus and do it right the first time!

Lace consistently!
As you go along, you can remove the wire ties or whatever. To finish it off, just tie a reef knot, cut the ends off long so you can tuck them under the leather, out of site.

Voila, leathered oars:

How it looks complete.
Finally, you must ask yourself: to button, or not to button.

A button is anything that prevents the oar from slipping out of your oarlock when you let go. All too often, this button is a strip of leather glued round the handle-end of the leather. I could not bring myself to add an abomination like that to my beautiful job, so at the moment I am rowing without a button.

Buttons are totally optional, so if you can row without dropping your oars too often, you don't need them. If I ever decide I need a button, I will probably get a nice bit of thin rope and tie a Turks Head on the leather. I think that might look pretty nice, and I can custom fit it so it looks and fits just right.

But so far, I don't see any need for a button. Ask me how I feel about this at the end of the summer!

Next time, I will wrap up my Cabin Boy refit and show you how he looks. I'll give you a hint: pretty darn good!

Next Episode: Water Line

28 March 2013

Outwales

With Cabin Boy's inwale system pulled out of the boat for varnishing (which is kinda boring to write about), it was time to think about the outwales. It's easy to think of these external pieces as 'rub rails', but in traditionally built boats, their main purpose is to help stiffen the sides so they don't flex when you are rowing.

This isn't so important in a glued-lapstrake boat, which are plenty stiff to begin with. I rowed Cabin Boy nearly every day all the way up the coast, and was never bothered by any flexing, even on those few unfortunate occasions when I really had to muscle my way to windward. But a little extra stiffness would make rowing that much easier.

So I started looking around for wood to use. I thought I had some half-round red oak molding left over from a home improvement project -- perfect, I thought, for an outwale. But my memory was faulty. The leftovers weren't half-rounds, they were quarter round. Dang.

It has been my goal to complete this refit without buying any wood, but what choice did I have? Nothing in my junk pile looked right. I had a bunch of molding that I'd experimented with as lofting battens, but they were all odd-ball shapes. Nothing that looked like an outwale.

So reluctantly I headed down to my local Big Box store. Much to my surprise, they didn't have any half-round molding either. Not even cheap 'white wood' half-round molding. I stopped at a more upscale wood emporium on the way home, and they had some oak half-rounds, but the prices made my eyes pop. I drove home thinking, there must be a better way.

After mulling this problem over for a day or two, it suddenly occurred to me that I didn't need to buy half-round molding. That was for amateurs! Well, I was still an amateur, but I didn't need to buy any stinkin' half-round molding. I could make it!

You might be thinking, 'well, duh!', but I was thinking 'Wow! What a revelation!'

And, yes, that's why I'm an amateur.

Anyway, I rushed back to my junk pile and after digging a bit, found a 10' long strip of white oak, about 1" by 1/2" in cross section. I figured it was just wide enough for two outwales if I ripped it exactly -- and I mean exactly -- in half.

I set up my table saw and feather board and, before I knew it, I had two strips, pretty much exactly the same size. Unfortunately, I was so excited, I forgot to take 'before' pictures, but here are the two 'after'  strips, all ready for shaping:

The secret of boatbuilding: mill your own wood
I quickly turned the square-sectioned strips into half-rounds with my block plane and some judicious sanding. This was so easy that I felt a little dumb for wasting all that time driving to lumber yards looking for half-round stock.

Never again.

I rounded off the end with a spokeshave and sand paper. Then it was ready to try on the boat.

From square to half-round
I was worried that the strip would edge-set when I curved it along Cabin boy's sheer, and it probably is, a bit, but not enough to notice.  So, I started drilling screw holes. The screws will go through the outwale and the sheer strake, and into the oak frames.

Lots of clamps needed
One thing I would change if I did it again would be to use smaller screws. I had #8 bronze screws on hand, so started drilling for that size, but realized half-way through that #6 would have been better. So I drilled the remainder of the wholes for #6 screws and used some cheap zinc screws temporarily. The bronze ones are on order.

Which proved you can never have enough goop on your shelves, or hardware. (My goop collection has become pretty impressive.)

Size (of screws) matters
And here's the first strake screwed on. I never get tired of looking at that John Atkin sheer line. Sheer beauty, even when built by an amateur.

Not too bad, though!
So the outwales are being varnished and Cabin Boy is outside in the warm weather, getting three coats of topside paint, and three coats of bottom paint. He should be ready for his grand relaunch some time next week, if King Neptune is willing.

Meanwhile, there are my oars to worry about...

By the way, my comments section was getting inundated by spam there for awhile, so I disabled anonymous commenting. But a number of people complained that they couldn't comment any more, so I've reenabled it. One of these days I'll figure out how to get Google to filter this spam automatically. Maybe.


Next Episode: Leathering Oars

19 March 2013

Don't Sweat The Small Stuff

The great thing about wooden boats is that it turns a summer hobby into one that lasts the whole year round. The main problem: my winters are now too short!

Yes, spring is right around the corner. Ignore that snow falling on the dock. It really is spring, and whether I'm ready or not, my local Harbormaster is going to kick the Blue Moon out of her snug winter berth on April 1st. Talk about practical jokes...

Since I've still got tons of work to do on the Blue Moon, I need to have Cabin Boy relaunched before the move out to the mooring. That means I have exactly 12 days to finish his refit. I'm not sure I'll make it.

After my thrilling success with Cabin Boy's breasthook, I was going to build a new set of quarter-knees, just for fun. But time pressure squashed that notion. The old knees are far from perfect. In fact, if I ever write a book called, 'How Not To Build A Boat', I'll put the photo below on the cover. The grain on these knees is all wrong, and sure to fail eventually. But the word 'eventually' provided just the excuse I needed to justify a shortcut.

The notch in the knee did not fit the inwale, but I thought a bit of trimming could solve that problem. Starting from the inwale, I drew a new curve freehand, and carried the piece over to my bandsaw.

Old knees don't really fit
A few minutes later, it fit good enough.

Note the sanding dust on the transom. Actually, the inwale didn't fit exactly. Almost, but not quite. Rather than stress about it, I screwed the inwale into place, and applied a bit of 80 grit sandpaper to the problem. A bit of light sanding smoothed the differences between the knee and the inwale, so that they flowed perfectly into each other. I'm sure I'm not the first boatbuilder to resort to this trick.

I wouldn't try this if the fit wasn't practically perfect, but if it is, no one will see the difference in the shape of knee or inwale.

Never mind all that varnishing!
I made quite a mess of Cabin Boy's varnish, but a bit of vacuuming and dusting solved that problem.

Make them fit = make a mess
Then it was time to fit the inwales to the breasthook. Again, the fit was almost perfect. A little sandpaper eliminated the mis-matches.

In the photo below, I've sanded the port inwale, and started on the starboard one. I remembered to stop and take a photo before finishing, so you can see that the starboard inwale is still a bit misaligned. No matter... it looked fine when I finished.

My new boatbuilding motto: don't sweat the small stuff.

Slight mis-matches in joinery can be fixed by a bit of sanding
Here's the breasthook, inwales, and knees all screwed together. Pretty sweet, I think.

Everything screwed together
A few more pieces were necessary, though. I needed oarlock pads. 4 of them, so I can have two rowing stations for my fore-'n-aft rowing seat.

I cut them out of a nice thick piece of Douglas Fir that I had in my junk box. I didn't like the color, so I decided to stain them. Another chapter in my "How Not To..." book.

<Sigh>

But they are good enough for this summer. I wasn't about to throw them out and start again. I'm not going to glue any of this stuff into the boat, so if I have the time and inclination next winter, I'll make new ones out of teak or ivory or whatever. For now, if anyone asks me what they're made of, I'm going to look smug and superior and say 'Zebra wood, of course."

Two sets of oarlocks required
So, after a lot of work, I had all the interior bits and bobs screwed in and fitting perfectly. So what was the next step? Yes! Pull them all out!

They all need to be varnished of course, but that is just time consuming. It should be done by this weekend.

Everything fit? Great! Unscrew them and start varnishing.
Next up, the outside of the boat. I want to affix some sort of outwale. Not sure what, exactly, but nothing complicated. But some old screw holes need to be filled, the topsides and bottom scraped and painted, and I need to finally give poor old Cabin Boy some bottom paint, as he'll be in the water all summer.

So what projects are you racing to complete? Spring is almost here...



Next Episode: Outwales

05 March 2013

A Useful Trick

A number of readers wrote to ask, why cut away the bottom of the hook? Won't it weaken it for no good reason?

The reason is purely cosmetic, as far as I know. Because it needs to be cut from a fairly thick piece of wood, for the reasons described in previous posts, the breasthook has a fairly clunky look if you don't cut a bottom camber. At least to my eyes.

But just hollowing out the bottom of the hook would both be difficult and weaken the wood. Is there a better way?

Hook before bottom camber is cut
As it turns out, there is! A very handy and elegant boatbuilder's trick from the olden days. The trick is to cut what is called a 'chamfer' into the bottom edge of the hook. A chamfer is a beveled edge that connects two surfaces. In this case, the hook's curved back and flat bottom.

The chamfer, correctly executed, will give the appearance of a cambered bottom, while still retaining most of the strength of the original hook. As a side benefit, it's simple and easy to cut with hand tools.

The first step is two draw the two lines that will define the edges of the chamfer.

The first line is drawn along the curved edge, parallel with the bottom, about 1/2" from the bottom. Unfortunately, I forgot to take a picture of this line, but the line will be clearly shown in the photos below. I used an ordinary carpenter's marking gauge to draw this line.

The  second line is drawn on the bottom, in a curve that follows the curve of the back edge. I drew this line with a pair of dividers, opened to about an inch. You can see this line in the photo below. Click on the photo for a closer look.

The chamfer must be wide enough to remove much of the wood in the notches, below the inwales. You want the curved back edge to be about as thick as the inwale, so the inwale and hook look all of a piece.

Then it was a simple matter of connecting the two lines with the chamfer, but cutting away the wood in between. This was easily done with my old, but very sharp draw knife. This tool scares the bejesus out of me, but there is no doubt that it gets the job done.

The draw knife removed most of the wood. I followed up with a spokeshave, and then sandpaper, to smooth the cut.

Cutting chamfer with draw knife
The photo below shows the complete chamfer. It also shows both lines that the chamfer was cut to.

You can see that very little wood was actually removed. It only took a few minutes to do both sides. The key, as usual with hand tools, is a good, sharp edge, a steady hand, and a bit of patience.




Here's an end-on shot showing how little wood I actually removed.




However, the effect is fairly dramatic. From a normal viewing angle, the hook looks much thinner than it is, because you can't see the chamfer. In other words, its an optical illusion. The hook is still very thick and strong. It just doesn't look that way.


It's hard to tell from the photo above, but the curved back edge of the hook is now about as thick as the inwale. So when the inwale is twisted into position and fastened, it will blend nicely into the curve of the hook.

So that turned out to be easier than expected, thanks to a boatbuilder's trick passed on to me through the Wooden Boat forum. A great resource.

Next up, those pesky knees at the other end of the inwale. The ones I have are weak and don't fit well. With my new-found breasthook skills, I should be able to fit a pair, but I'm not sure I have enough oak left in my shop to build them! Time to start digging through my scrap box...



Next Episode: Don't sweat the small stuff

02 March 2013

Cutting Camber

Once I had my test hook fitted, I realized I could use it as a template for cutting out the real hook. I just laid the Douglas Fir template on top of my glued-up oak blank, drew the outline and cut it out. Then I used the template to eye-ball the angles for the bevels. In a few minutes, I had a copy of my test hook.

Then it was time to cut the camber in the top of the hook. I'd been thinking about how to cut this gentle curve into rock-hard oak. You can see from the picture below that there was quite a bit of wood to cut away.

A friend recommended a drawknife or a spokeshave, but I thought that would be a lot of work, and I didn't think my drawknife skills were up to producing a symmetrical, smooth curve.

In the end, I decided to use the trick used to create round spars. I'd make a flat cut to remove most of the wood, then shape the two flat sides into a curve with a block plane.

Lots of 'meat' to cut away
The picture below shows the flat cut. I made this by hand on my bandsaw. I just held the piece at the right angle and pushed it through the saw. A little rough-and-ready, but it worked quite well.

After cutting out the notches for the inwales, I cut out the curve. This looks straight, but it's actually beveled at the same angle as the notches. This makes sense if you think about it, because the inwale is rectangular in shape. The inwales lies against the notch, so if the curve is to blend smoothly with the side of the inwale, it must be at the same angle as the notch. QED!

I realized this while cutting the notches, so as long as I had the bandsaw at the right angle, I cut the curve at the same time.

Caption
In the photo above, you can see there is still plenty of wood to shape into the curve. I penciled in the upper and lower edges of of the inwale, and then moved the piece to the bench. I used a block plane to remove the rest of the wood, and to shape the curve down to the lines.

Caption
The picture below shows the job half done. The port side is curved, the starboard side is still flat. With a sharp block plane, it only took a few minutes to shape the curve. It was much easier than I expected, actually.

Caption
Another view of the same stage, with flat cut on left and round camber on right.

Caption
When both sides were shaped, I tried it on for size. A pretty good fit, and a very pleasing shape, if I do say so myself.

All in all, this step was worse in the anticipation than the execution. I was 100% sure I'd ruin this piece cutting the camber, but I was pleasantly surprised at how easy it was, once I came up with a plan.

Smooth camber
The main difficulty with these breasthooks is all the bevels and curves. I had a hard time visualizing all of them, no less figuring out how to cut them. But just required a bit of thought and time.

This is one of those jobs that you don't know how to do, until you are done. That seems like an unbreakable paradox, like time travel, but some how you need to break it.

Speaking of which, my next step is to somehow cut the same camber into the bottom of the hook. I honestly have no idea how to do this, so time to have a sit in my thinking chair...



Next Episode: A Useful Trick

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