Symmetry

So, I bet you were wondering how I cut the 'gains' on my first plank after it had been fastened to the forms. It wasn't easy...

What are 'gains'? On a lapstrake boat, like the one below, the planks overlap for the full length of the boat, but overlap magically disappears at the stem (and sometimes at the transom).

Cabin Boy's macho brother

photo from the 1920s... photographer unknown

There are several ways to perform this disappearing lap trick. I chose the method that looked the simplest to me: cutting a sloping rabbet or gain along the edge of each plank.

Luckily, I had picked up an old Stanley rabbet plane at a flea market over the summer. This No. 78 plane has guides for both the width and depth of the rabbet, but because the plank was already fastened to the frame, the guides were in the way. I unscrewed them, tuned up the blade, and got to work.

By the way, I've read several blogs where the builder laments that he doesn't have a rabbet plane, and then proceeds to make a hard job even harder by making do with the wrong tool. When I started to look for tools, I assumed it would be more or less impossible to find something as exotic as a rabbet plane. Wrong-o! Even on suburban Long Island, it is easy to find all sorts of great hand tools at garage sales, flea markets, etc. And they are cheap. So there's no reason not to have one. Or two. Or three... (Warning: buying planes is addictive.)

 

 My hefty (and very handy) Stanley No. 78 Rabbet Plane - guides removed

photo jalmberg

Of course, I couldn't cut a straight, sloping gain without some sort of guide, so I clamped this bit of plywood along the lap line (for a 3/4" overlap).

Then it was fairly simple to cut a slopping gain, about 12" long. 

  

Using a clamped on guide to cut the rabbet

photo jalmberg

Here's a shot that shows the basic idea... You just run the rabbet plane along the guide. To make the gain slope, you just make more passes at the end. I did it all by eye... I'm not sure how to cut this slope more scientifically, but since the plywood was only 1/4" thick, we are not talking about a deep gain.

Speaking of depth, to make the lap totally disappear, you need to cut the gain so the end is paper thin. This end is backed up by the transom or stem, but I didn't have that kind of nerve. I left some thickness at the end of the gain and plan to cut a corresponding gain in the overlapping plank, so neither plank is too think on the edge.

  

Cutting the rabbet

photo jalmberg

Of course, you need to cut a gain on both ends of the plank. I started with the easy one at the transom. The one at the stem was twice as hard to cut, because the plank twists into the stem, and the stem gets in the way of the plane, and stops you from cutting the gain all the way to the end, even if you move the blade to the front of the plane, as the Stanley No. 78 allows.

In fact, it was such a pain to cut the gains near the stem that I totally forgot to take any pictures. Suffice to say that I cut as much as possible with the plane, and then finished the job with a chisel. 

Too bad, because it would have been a classic "How-Not-To" tutorial!

  

Cutting the rabbet on the bench

photo jalmberg

If you are not a complete blockhead who fastens the plank to the forms before cutting the gains, you can do it the right way, as I did on the port-side garboard plank.

This is the right way to do the job... firmly clamp the plank to your bench and plane away. You can even use the width and depth guides, which I've re-attached, above.

This gives you a nice, clean, sloping gain in about 1/8th the time. 

With the gains cut, it was time to fasten the second plank to the boat. When I finished, I stepped back to take this photo:

 

Both garboard planks fastened

photo jalmberg

Wow! Neither this photo, nor the plans of Cabin Boy really communicate the lovely curves that make up this small fraction of a boat.

I'm not really sure how John Atkin did it... The sides of the forms are straight, but every part of the boat curves in an almost magical way. Particularly the garboard planks, which not only curve but twist at both ends.

I must admit I had recently been wondering if all this work was worth it... There surely are easier boats to build, and easier methods to use.

But for the first time I had a inkling of Cabin Boy's final shape, and I fell in love with the design, all over again. Yes, it is worth all the work.


>>> Next Episode: Over the Hump?

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Mountain Climbing

There are a lot of good boat building books (BBBs) out there, and I own many of them. But when I started to build Cabin Boy, I decided to pick one guru to follow. That guru, for me, is Greg Rössel and specifically his book Building Small Boats.

Not only is Mr. Rössel a master boat builder, he's a very good writer, and as I finally fastened my very first real plank on to Cabin Boy, a line from his chapter on lofting came back to me:

"Consider, however, the matter of understanding. One can intellectually get the idea of what a topographic map means without ever climbing a mountain, but the lines on that map gain enhanced meaning and purpose after you have climbed the mountain."

I'm still struggling in the foothills of wooden boat building, but I can finally see the summit, and it looks grand from where I'm standing.

 

Topographical map of K2

The North Face of K2

photo wikipedia commons

I have said several times that I often don't know how to do something until I've done it, which is darn inconvenient. But after bombing out on my first attempt to spile a garboard plank, I figured the lessons learned would make the second attempt easier...

Lesson 1: Don't cheap out on your spiling stock. The first thing I did was change my spiling stock from junk 1/4" plywood to 1/8" Luan plywood. As usual, a number of people, including my boat building friend Roger, told me to use Luan, but I cheaped out and tried to use what I had on hand. Big mistake.

1/8" Luan is much more flexible than normal plywood, and that lets it curve around your forms without cracking. Nothing worse than spending a couple hours spiling and cutting out a pattern, only to have it crack in half when you try to bend it around the forms. Plus its cheap... I paid less than $10 a sheet for it at my local lumber yard.

Don't be fooled by the fancy name, 'Luan'. That's just the type of wood its made from. It's cheap, readily available, and perfect for the job. I won't use anything else from now on, unless I find something even better.

Photo 1: Three part spiling batten, made from 1/8" luan plywood

photo jalmberg

Lesson 2: Don't edge set your spiling batten. At all!  The second thing I did was to use a three-part spiling batten. The three parts can be positioned independently on the forms, so they stay between the lines you are trying to spile without any edge setting. Just tack them into place on the forms, and then splice them together with gussets made from small pieces of luan.

 

Photo 2: Plywood gusset epoxied in place

photo jalmberg

Lesson 3: Simplify the stem rabbet as much as possible, and then cut it! After spiling the hood end (the part that fits into the stem rabbet) of the garboard the first time, I realized that the rabbet along that short segment of the garboard plank was nearly a straight line. I decided to make life easier for myself and pretend it was a straight line.  

In other words, I decided to turn that curving stem rabbet into 4 straight line segments, one for each plank. This might not be possible for a stem with a big curve in it, like the round-bottom boat in Greg's book, but Cabin Boy, and most other flat-bottom boats, have very little curve in their stem rabbet.

Turning the rabbet curve into a straight line made it easier -- and less intimidating -- to cut the rabbet, and much easier to take advantage of the next lesson...

Lesson 4: Don't even try to spile the hood end of the spiling batten. Instead, make a pattern that fits into the stem rabbet, and use that as the forward part of your spiling batten.

Since I had eliminated the curve in the stem rabbet, it was easy to cut a pattern that fit into the rabbet. I did this by cutting a piece that was close, and then trimming it until it fit.

If you look at Photo 1, above, you will see that the first part of the 3 part spiling batten is actually a pattern that fits snugly into the rabbet, and along the chine log. So, instead of spiling the hood-end of the plank, I would just trace around the pattern. Easy-peasy, and more accurate.

After learning and applying these lessons, I was able to accurately spile the garboard plank. With the spiling done right, the rest of the job was easy.

 

Unspiling onto the pattern stock

photo jalmberg

First, I unspiled my spiled points on to my pattern stock, which was also luan plywood, using the same techniques described in A Garboard Tragedy.

Cutting out the pattern with jigsaw

photo jalmberg

Then I cut out the pattern, this time trying a jig saw, rather than a bandsaw. I reasoned that a jigsaw was basically a hand-held bandsaw (not really, but pretty close), and that it was easier to maneuver the jigsaw around the sheet of plywood, rather than maneuver the plywood through the bandsaw.

Now, jigsaws don't get much respect from boat builders or wood workers in general. I'm sure if I ever reach the summit of boat building, I'll probably agree. But down here in the foot hills, I must report that a jigsaw -- fitted with a narrow, fine toothed blade -- did a much better job than the bandsaw. In fact, a 'good enough' job. See Final Lesson below for more on this subject.

 

 Trying the pattern on for size

photo jalmberg

Once the pattern was cut out, it was time for the big test... Were the lessons I learned correct? Was my spiling job 'good enough'? Would the pattern fit onto the forms without edge setting?

Joy, oh, joy... it did. Nearly perfectly. I trimmed the hood end to fit more tightly into the stem rabbet (I had purposefully left a little 'extra' on that end, to allow for fitting), smoothed the long edges a bit with a plane, and I had a perfect fit. No edge setting.

Did if feel good? You better believe it!

 

My first actual plank, glued and fastened

photo jalmberg

After that, it was just a matter of lying the pattern on the sheet of 1/4" Okoume marine plywood, tracing around the pattern, and cutting it out with the jigsaw.

I then bedded it onto the oak stem, chine logs, and transom with a liberal slathering of 3M 101. I will be epoxying the planks together at the laps, but am using this flexible sealant at the stem and transom because I've heard that epoxy doesn't bond all that well with White Oak. There is much controversy over this question, and I don't have enough experience to weigh in on one side or another. The bottom line for me is that using 101 is a safe route. I know it will work.

Plus I'll get to compare the 101 bonded joints with the epoxied joints. If I notice any difference, I'll blog about them.

Update: after being towed 2000 miles up the east coast of the US, and suffering more abuse in a year than most dinghies get in a decade, neither joint ever leaked a drop. Unfortunately, 3M 101 is no longer available!

I then fastened the plank with #8 silicon bronze screws... perhaps 'over fastened' would be a better way to put it. One thing's for sure, that plank isn't going to fall off.

I did make one mistake... I should have done one thing before fastening the plank on, but I'll deal with that little whoops next time. Experienced boat builders have already noticed my omission, I'm sure.

Final Lesson: Don't aim for perfection on your first build.  This is a lesson I have finally learned myself. I have not seen it mentioned in any boat building book -- possibly because they are aimed at people with more wood working experience than me. I'm not sure.

But there is a thread of perfectionism in the boat building culture, I think. You know the kind of boats I mean: perfect lines, masterful joinery, paint job by Michalangelo, a varnished sheer strake... the kind of boats that are celebrated on the cover of Wooden Boat magazine and displayed by their proud builders at wooden boat shows.

These boats are built by builders who have reached the top of the mountain and are brilliant. But to aim for perfection like that with your first boat is like a first time portrait painter trying to produce a masterpiece on the first go. It just ain't possible! At least, not for me.

It helps, I think, for first time builders to accept the fact that we are learners, and to aim not for perfection but for the best we are capable of.

This allows one to focus on learning the core skills like lofting and spiling and cutting rabbets. Only after mastering these very difficult skills does it make sense to focus on the finer skills needed to produce a masterpiece.

Olde-time boat builders would agree, I think. They spent years as apprentices, learning their craft at the feet of masters, while building many boats. Only amateurs like me, with no wood working experience at all, would start with higher expectations. 

The boat builder that has fun, and ends up with a boat that floats, is more likely to build a second boat, and a third... gradually moving up from the foot hills, to Base Camp 1, to Base Camp 2...

I don't know if I'll ever reach the summit of the boat building mountain, but I do think the step-by-step method is the way to get there.

You can climb any mountain, as long as you climb it slow enough.


>>> Next Episode: Symmetry

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A Garboard Tragedy - Act 2

All the BBBs (boat building books) tell you that when you spile, you must lock down your dividers and use exactly the same radii for all your arcs. Being an overly-clever chap, I saw straight through this lie.

This brilliant insight almost tripped me up, of course.

But before I explain myself, let me make up two definitions. There may be words for these processes already, but I don't know what they are. (If you happen to know the correct terminology, please pass them along using the comments form below.)

In this blog, I will use the following definitions:

To Spile a Point: to draw an arc from a point on the form onto a spiling batten

To Unspile a Point: to draw two arcs from an arc on a spiling batten, onto pattern or planking stock, thus recreating the original point.

With those definitions in mind, I can now easily say that you can use any divider settings you want for any point, as long as you use the same setting for spiling and unspiling that one particular point.

For example, I used a pretty wide divider setting up in the bow, where the distances from the points to the spiling batten were several inches, and a smaller setting in the stern, where the distances where much smaller.

To enable me to reset the dividers correctly when unspiling the points, I marked off both divider settings on the batten itself, by marking a starting point on the batten,  drawing an arc, and labeling it. Once this setting was recorded on the batten (it could have been recorded anywhere, but the batten was handy), it would always be possible to reset the dividers to the proper size.

Of course, you also need to record which set of points use which settings... which I will definitely do the next time I use this marvelous trick...

Actually, as Bob Easton helped me see, you don't need to use this trick at all. It is always possible to use the same divider setting for all points, which is much less error prone. However, even if you are using the same setting for all points, I still think it's a good idea to record that setting on the batten, just in case...

Resuming our tragic story...

Once the spiling batten is tacked onto the form, the next step is to spile all the points you need onto the batten. This is very easy to do. Just put the pointy end of your dividers onto the point to be spiled, and draw as long an arc as possible. Keep the dividers perpendicular to the spiling batten for maximum accuracy.

By the way, this blog post is a classic UnlikelyBoatBuilder how-not-to guide. Practically everything I show you in this post is a mistake. Builder beware! Read the next post before you run out and try spiling!

In the photo below, I'm spiling from the rabbit line. Notice that I haven't cut the rabbet, yet.

 

Drawing an arc from rabbet line to spiling batten

photo jalmberg

Once all the points you need are spiled onto the batten, remove the batten from the forms and lay it flat on your pattern stock. 

If you have more nerve than me, you could spile directly onto your planking stock, but my expensive sheet of marine plywood would have been the size of a matchbook by the time I finished learning how to spile. Much cheaper to practice by making patterns. When the pattern fits, then trace it onto your valuable planking stock.

Spiling batten removed from forms and clamped to pattern stock

photo jalmberg

I then clamped the spiling batten onto the pattern stock. I didn't want the batten shifting around as I unspiled the points.

Once secured, it was pretty simple to unspile all the points. You just pick two points on each arc, and draw two arcs onto the pattern stock. Ideally, the two arcs will cross at right angles, but sometimes that's not possible.

Rediscovering original points on pattern (same point as above)

photo jalmberg

When all the points are unspiled (isn't that a useful word?!?!), just connect with a batten in the usual way.

This is when I discovered that I had used the wrong divider setting for one set of points. No big deal, though. I just bypassed them. The batten supplied the missing points.

 

 Connecting the spiled point with a batten

photo jalmberg

Here's another view of the unspiled line of the garboard plank... Looks great, right? Of course, there are two lines to draw.

  

 The same line from another angle

photo jalmberg

Once the perimeter of the plank has been transfered to the pattern stock, it's time to cut it out. I used my bandsaw to cut out this pattern, but I must say it is not easy to guide a floppy, 8' piece of plywood accurately through my machine. After cutting out this one piece, I was looking for a different way to cut out these long patterns.

Cutting out the pattern on the bandsaw

photo jalmberg

Now that I had my pattern cut out, it was time to try it out on the forms. Using the BBB-approved method, I clamped the pattern to the chine log in the middle of the boat, then clamped down the bow end. This lined up pretty well. So far, so good!

But then it was time to clamp down the stern end. As you can see in the photo below, I had two problems:

First, the pattern did not follow the line of the chine log... at all! It wasn't just a little bit off, it was several inches off. Not even close!

As if the pattern was disgusted by my spiling failure, it cracked as it bent around Station 3, right in the middle of the boat, where the angle is smallest.

Or perhaps the pattern was just anticipating it's fate, since it shortly suffered a few more 'cracks'. In fact, it ended up as kindling for that night's fire. 

 

Whoops... how the finished pattern should *not* look!

photo jalmberg

But before reducing my hard-won pattern to firewood, I sat in my 'thinking chair' and stared long and hard at it. What had I done wrong?

It wasn't my rebellious use of two divider settings. That did cause an error, but the error was so large and so obvious that I just discarded those points.

Could it be my spiling or unspiling technique? It was the first time I'd done it, but the laws of Geometry seemed to rule out any significant error. My points might be off the thickness of a pencil point or so, but not much further than that.

There was only one mistake that could have generated such a large error, I reasoned. I must have edge set the spiling batten when tacking it onto the forms. I had no proof, but the more I thought about it, the more I was sure that must be the error.

Source of the problem... edge set spiling batten

photo jalmberg

When I sat down to write this blog, this was the first photo I looked at. Remember that the two-part spiling batten is made from two straight strips of plywood, spliced together with a gusset. 

So how did the aft strip of plywood curve so sweetly along the long edge of the chine log?

I didn't think I edge set it, but I must have. That must be the cause of my problem, I thought...

Such a small mistake... so much work wasted...  That must be the mistake, mustn't it? 

There was only one way to find out...

>>> Next Episode: Mountain Climbing

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A Garboard Tragedy - Act 1

Last week I woke up and decided I wanted to learn to play my favorite piano piece, William Bolcom's "Graceful Ghost Rag".

It is true that I don't actually know how to play the piano, but I figured if I just practiced this one piece for a bit, I could figure it out in a reasonably short time.

After all, learning anything is just a matter of time and practice, right?




Well, as my favorite piano teacher (Helena) will tell you, time and practice are not the only requirements. You need to practice what you are ready for.

I could practice the "Graceful Ghost Rag" from now until doomsday, and never get it right. The reason: I don't have the necessary foundation for it.

However, if I started off with Book 1 of any piano method (complete with cute animal pictures and the obligatory rendition of "Merrily We Roll Along"), and work my way up the scales (at least the 45 basic ones), and practice an hour or two a day, then I just might be ready to start working on the "Graceful Ghost Rag" in 5 years or so. At that point, I'd know enough to understand what I was practicing.

No doubt a good book and/or good teacher can help flatten the learning curve, but there's no short cut for practicing, or getting around the rule that you can only learn what you are ready to learn.

I ran into this seemingly universal law this week when I tried (and failed) to 'get out' a pattern for Cabin Boy's garboard plank. As I sat in my moaning chair, thinking back on my dismal failure, I realized that my mistake had been in the very first step, and that everything I'd done in subsequent steps had been doomed to failure.

And this put a smile back on my face. I will try to explain...

The first step in getting out any plank is to spile it. Determined, this time, to follow the advice of the Boat Building Books as closely as possible, I read and re-read the pertinent sections of Greg Rossel's Building Small Boats until I believed I understood exactly what I was supposed to do.

One important point was to not try to use one, long, single piece spiling batten. Such a batten cannot be curved around the forms in the right place without being edge set. And edge setting a spiling batten is a sure path to depression, suicide, and worse, I was assured.

What does 'edge setting' mean? To see it for yourself, cut a one inch strip off a piece of copy paper. This long, thin rectangle is your 'plank'.

Then draw a straight line on another piece of paper. Lay your paper strip so it's upper edge aligns with this straight line. See how your 'plank' lies nice and flat?

Now draw a line with a slight curve and try to lay the upper edge of your paper strip along this curve. You can bend the paper so it follows the curve, but the inside edge of the strip will curl up. Try as you might, it is not possible to have your straight 'plank' both follow the curve and lie flat. It must stand up on its edge to follow the curve. Your 'plank' is thus 'edge set'.

To avoid these horrors, I dutifully built the recommended two-part spiling batten, made from two straight pieces of 1/4" plywood, spliced together with my first gusset.

 

My first gusset... clamped while the glue dries. Also fastened with screws.

photo jalmberg

Here's the spiling batten tacked into place in between the bottom of the chine log and the 'lining off' lines that mark the top of the garboard plank.

 

My first spiling batten

photo jalmberg

When I sat down to write this blog, this was the first photo I looked at. As usual, this photo meant nothing to me when taken, but was like a thunderclap of Revelation after the fact. Experienced boat builders can already see the problem, I'm sure.

"In religion and theology, revelation is the revealing or disclosing, or making something obvious through active or passive communication with supernaturaldivine, ...). It is believed that revelation can originate directly from a deity, or through an agent, such as an angel. One who has experienced such contact with or communication from the divine is often called a prophet." 

- Wikipedia 

However, not being a prophet, I didn't receive the message, and was thus doomed to play out this tragedy, until it's bitter end.

Once the spiling batten is tacked into place on the forms, it is time get out your dividers. I used the ones I use for navigation.

The purpose of spiling is to capture the perimeter of the complex space that a plank needs to fill. More specifically, you want to capture just enough points on the perimeter to allow you to connect the dots and draw the complete shape.

One way to spile is to use a simple geometrical fact: if you draw an arc around a point "A", you can rediscover the point from the arc by drawing two arcs of equal radii from any two points on the arc. The two arcs intercept at the original point.

 

Geometrical basis of spiling

photo jalmberg

In spiling the garboard, you choose various strategic points on perimeter of the proposed plank: points on the stem rabbet, chine log, transom, and the lap points on the station forms.

From each of these points, you draw an arc onto the spiling batten. Ideally, the spiling batten is big enough so that all the arcs are of equal radii. That minimizes the chances of error. Unfortunately, my spiling batten was NOT big enough for that, but I thought I had a way around that problem.

Naturally, this hubris generated at least one big error, which I'll describe tomorrow.

>>> Next Episode: A Garboard Tragedy - Act 2

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Lining Off

Resuming our Tale of Two Boats...

The Blue Moon's hull being painted, I relaunched her, splashing half a bottle of Blue Moon beer on her bow (no need to waste the whole bottle!)

Then Bob and I motored her down to her temporary new home -- a dock in the Steinhatchee River. With her long bowsprit, the slip was a bit short for the Blue Moon, so we had to back her in. NOT an easy thing to do with her long keel and small motor.

The motor did manage to get her moving backwards... slowly... but turning was a whole other thing. Fiddle with the rudder as much as we might, her long, deep keel kept her moving in a straight line. There was no way I as going to be able to back her into the slip, even without the current and cross wind.

If I'd had Cabin Boy with me, I would have warped the Blue Moon into the dock, neat as you please. But being dingyless, we had to depend on the kindness of the 5 or 6 bystanders who had gathered on the dock to comment and watch the show.

It wasn't elegant, but we eventually manhandled the Blue Moon into her slip, without scratching her lovely new paint.

Blue Moon in her temporary berth

photo jalmberg

I still need to paint the deck -- with a combination of white and that nice Bristol Cream used on the rail and waterline -- but I was out of time. I needed to get back to New York where Helena, kids, and business concerns all needed attention.

So, leaving Blue Moon tied up and in the capable hands of the marina (with Bob available to check up on her occasionally), I headed back to the frozen north and Cabin Boy.

The next step in building Cabin Boy was to plane the chine logs flat, so a straight edge (in lieu of a bottom plank) lies flat on the chine logs and keelson. 

Before planing, the chine logs are edged inwards (see photo, below). A straight edge (2x4) doesn't lie flat on the chine log. It sits on the chine log's edge.  I needed to take off that edge.

Straight edge (top) sits on edge of un-planed chine log

photo jalmberg

The right tool for this job was my nice wooden plane. I didn't take a lot of time over this. I just planed the chine logs by eye so they 'looked' flat, and then checked then with a straight edge (the edge of a 2x4.) 

Planing the chine logs so they are flat and level with the keelson (in background)

photo jalmberg

And here's how one of the chine logs look after planing. See how the straight edge now sits flat on the chine log. It's not a lot of work. We're talking about 10-15 minutes with a hand plane. Easy peasy.

Chine log planed flat

photo jalmberg

That done, the next step was to 'line off' the hull. 

Now, if I'm honest, I have to confess that I didn't really need to plane the chine logs before lining off the hull. I was just procrastinating, because I really didn't know how to tackle this 'lining off' thing.

Lining off is the process of deciding where the planks on your boat are going to go. It is one of those "more art than science" parts of boat building. One of those chapters where the Boat Building Books all go fuzzy with talk like "if it looks right, it is right".

Okay, fine. I get that. That's how you know when you are done. But how do you begin? I had no idea.

Like many things, you just need to start and see how it goes. I've often noticed that you never really know how to do something until you've done it. It's a chicken-and-egg problem, and the only way to crack it is to start, even though you don't know how to start. You just need to jump in and start working at it, trusting (hoping?) it will all become clear in the end. 

To get rolling, I noticed that Cabin Boy's plans included a profile drawing that showed an exterior view of the 4 planks. This was a good clue. The profile did not show the whole plank -- in particular, it did not show the parts of the planks that were overlapped. This is a lapstrake (or clinker) design, remember. 

However, I reasoned that if I allowed a 'standard' overlap of, say, 1", then it would be possible to measure the width of the planks right from the profile drawing, using my architect's rule.

For some reason, this process was extremely time consuming. Mainly because I made every mistake possible, including forgetting that the profile plan was right side up, and the boat was up side down. Yes, I measured the dimensions of the shear strake (the plank at the top) and used them to measure the garboard plank (the plank at the bottom). Luckily, I wasn't holding a sharp tool when I discovered this error. Duh!

However, after numerous errors and false starts, I had the 'first draft' of my lines, laid out with battens on the forms. Whew!

(By the way, I still haven't found a way to cut battens that I'm satisfied with. I'm using my bandsaw to cut them out of reasonably straight-grained white pine, but its not easy to cut a perfectly straight, 8 foot line, so my battens are full of waves and bumps. I know they look straight in the pictures below, but believe me, they are not. 

If you have a system for cutting nice, straight battens, please share it with me by leaving a comment below, or emailing me at john@unlikelyboatbuilder.com.)

Lining off by science and mathematics... a good first draft

photo jalmberg

Anyway, I call the above 'first draft' because this is as good as I could get the lines using science and mathematics. And it wasn't quite good enough. If you study the photo above carefully, you'll see what I mean. The lines just aren't right.

Yes, I measured the profile plan as carefully as possible, and I laid out the measurements using as much precision as possible. But, apparently, science and math can only get you so far when lining off. I needed to turn to art.

By 'art', I mean eye. I had finally reached the point where the Boat Building Books made sense to me. The only way to finish the job was to move the battens around until they 'looked' right. 

Amazingly, this was much easier than I expected. After pulling a few tacks and letting the battens 'flow' around the molds as they wanted to do, rather than forcing them into my mathematically 'precise' locations,  they suddenly looked 'right'. 

Lining off by eye... better!

photo jalmberg

So, once again, I have to report that olde-time Boat Building Masters knew what they were talking about. Your eyes and your battens will tell you what to do if you just give up a bit of control and let them speak. Don't fight them.

Tomorrow, another frighting task: spiling the planks. I have no idea how to do this, but apparently I'm not going to let that stop me.

Onwards!

Next Episode: A Garboard Tragedy - Act 1

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