Correcting Mistakes II: The Usefulness of Square Corners

When we went to put sheets of plywood on the top, er, bottom of the boat hull, they didn't really line up.  WTF?  It seemed unlikely that four sheets of plywood were manufactured not quite square, so we had to look elsewhere.

When we assembled the stringers with the cross beams, we had squared the pieces more or less, but little errors at the quarter inch level really add up over a 20 foot boat.  We hadn't thought to square the boat up as a whole unit.

So now we measured corner-to-corner to find that there was a difference of about and inch and a half.  Not giant, but enough to make the plywood fit funny on top, er, bottom.  We hadn't made a rectangular boat hull, we'd made a parallelogram.

That night I had a dream:  We were using a come-along to square up the boat.  Brilliant!  Thanks, subconscious!  So that morning, we grabbed my come-along and screwed big-ass eye bolts into the opposite (long) corners.

My come-along didn't go the distance, so we borrowed a hooked chain from the boat trailer and doubled it up.

We worked for a while to find the route for the chain and the come-along that when tightened wouldn't tear the building form apart.

We then started working my rusty come-along to square the boat.  Kai was working the come-along originally until she realized with horror that one of the two stops that keep the ratchet from violently unratcheting broke off and fell out.  She didn't want to have to explain to people for the rest of her life about that gnarly scar across her forehead so she passed on that job.

So I got to work the come-along.

After a half dozen clicks under tension the boat was approaching square.  Oh wait, too far.  Back off.  Whoops, too little.  More tension.  We played that game back and forth for a while.

Until finally the two corners were within a quarter inch of each other. Once we got the sheeting on the bottom screwed and epoxied down, the boat would stay square.

Next we sheet the bottom of the hull.

Correcting Mistakes I

Today, the chickens come home to roost.  Remember that pesky three degree error?  As we assembled each of the stringers, we could see that the pieces didn't come together quite right.  It would have been laborious but simple enough to cut new ones, but oh no. 

I figured I could just cheat the difference on either side.  But that left an irritating overhang on the ends of the stringers.  We knew that when we put sheeting on the ends, that little overhang was going to be a problem.

So I attacked the overhang with a handsaw. 

And then a sander.

It came out looking pretty sweet. 

Three degree error erased.  Like it never occurred.  Maybe we can just forget it ever happened.  (Well, except for the blog, I guess.)

So now we put the first thin coat of epoxy on all the frames.

This prepares the way for us to start sheeting the bottom and the ends.

First Build Day: Building Form

After months of hemming and hawing over plans and possibilities and uncertainties and even driving to the Middle of Nowhere to get a trailer, finally we start building the boat.  Or at least we build something that is essential for building the boat.

The Glen-L plans call for making a building form upon which to build the boat.  With the building form you get the boat at a height you can work on it, as well as have a level, plum, and square form upon which to assemble the individual pieces.

From these photos you also get an idea of just how beautiful a location we have to build the Shantyboat  Thanks to Lawrence and his family for their generosity, and perhaps their healthy curiosity as they watch the project slowly come together from a pile of lumber to a boat.

I actually found an error on Glen-L's otherwise flawless building plans.  The plans called for the cross spalls to be 97", which is one inch over 8' (a frustrating waste of conventional length lumber).  Another measurement in an end view gave half the measurement of the cross spall as 3'-11 1/2", or 95 inches. As usual after a little back and forth clarification, I got a message from Gayle:

Wes,

I had Glen take a look at the plans and here's his
response:

Seems to be an error. The cross palls should
extend 3' 11-1/2" each side of CL or 95" long. You
have thickness of side planking, plus FG plus rub
rail to obtain beam of 8' 2". This will make an 8'
width on the bottom to match the two 4' wide PW
panels. 

Gayle Brantuk

This building form was mostly made of scrap lumber.  The stringers (the frames of the boat that run longitudinally) will sit on top of and perpendicular to these cross spalls on top of the building form. 

I actually built the form wrong, at least according to the plans (the side pieces are reversed inside out).  And though it didn't hurt anything, it set me off on a cascade of self-recrimination at my carelessness.  If I assembled the boat with as little attention to detail, I would be wasting material, causing undue frustration, and making an ugly boat.

This made me rethink ways I could balance my eagerness with my sense of precision.  The next week I switched gears from my cavalier construction of the building form to a slower more careful approach.

Jen and Kai both helped me make the building form.  And after Kai and I had a pretty pointless conflict, I realized one very important boatbuilding need that I hadn't taken into account for people working hard in the hot sun all day:  Snacks!