Monday, November 25, 2013

The Utility: First planking panel attached

Over the weekend, I was finally able to attach the aft starboard side panel with epoxy and screws.

First, before I removed the panel from the boat’s framework, I traced the lines of the chines, sheers, and frame to the inner surface of the plywood. That way, I would have an easy visual reference for where to spread the epoxy. I also drew reference points on both the plywood and the chine to help align the panel when it was time to put it back on.

I removed the panel & set it aside, and staged all the items I’d need nearby: chip brush, extra latex gloves, awl, clamps, screwdriver, and the silicon bronze screws. I kept extra screws close at hand just in case I stripped any screw heads. This time, I put some old newspaper down on the floor to catch any drips of epoxy... right next to the earlier dried globs that I’m going to have to sand off of the concrete at some point.

Planking panel removed & waiting for epoxy.

Frame outlines made a great reference for spreading the epoxy.
Waiting for epoxy.
Some of my alignment was a bit off when I drilled into the sheer. I'll have to be more careful next time.

Same drilling alignment issue with the transom frame.
With everything ready to go, I mixed 6 oz of Silvertip Gel Magic epoxy. Gel Magic is a highly-viscous 2:1 mixture (2 parts resin to 1 part hardener). Its thickness makes it ideal for applying to vertical surfaces and for filling gaps. In this way it is very similar to Glen-L Poxy Grip.

The GelMagic components are color-coded.
Using the chip brush, I applied epoxy to both the plywood panel and the mating surfaces on the boat’s framework. At one point, I was concerned that 6 oz of epoxy would not be enough to do the job. Luckily, however, it was just about right, with a minimal amount of waste.

Wearing 2 layers of disposable latex gloves, I roughly aligned the panel with the reference marks I’d made earlier, and held it in place with one clamp. The Irwin spring clamps are great for this, as the springs in them are quite strong. Next, I used the awl to align the first holes, adjusting the clamp as necessary. I hand-threaded the first screw, then changed gloves to avoid getting too much epoxy onto my screwdriver.

After driving the first couple of screws, I clamped the rest of the panel into position. Hand-driving the screws went very smoothly. I found that using a ratcheting screwdriver with an oversized handle is just ideal for this task. I also found that I’d over-beveled some of the holes, as a few of the screw heads went slightly below the surface of the plywood. I’ll create less of a bevel next time.

With the panel fully “glued and screwed” into place, I used the putty knife to scrape away excess epoxy from the areas where I’ll need to join more wood: the chine and sheer where the forward planking panel will butt up against the aft panel; and the interior joints of the chine and sheer to the aft panel where the backing piece for the butt joint will be attached. I then used the putty knife to fill the screw holes with epoxy.

It was while using the putty knife that I realized the major component of this process that I’d forgotten: 

A rag. 

Thankfully, the laundry basket was nearby. 

There’s one less item I’ll have to wash, dry and fold. Hopefully, however, I will remember to get shop rags next time.

Alignment marks & filled screw holes along the chine.

Excess epoxy was scraped away from the chine so it won't interfere with fitting of the forward panel.

The small gap on the side of the transom is now filled.

Seam of cured epoxy against frame #1.

On the interior seams, I scraped away excess epoxy so it won't interfere with fitting of the backing block for the butt joint.

Wednesday, November 20, 2013

The Utility: Incremental progress on the planking

It has been a week of small, incremental progress on the Utility. Even when you can only spend 15 – 30 minutes a day on the project, each little step gets you further along, and can take much of the prep work out of the next major task.

So it has been for me over the last several days. One morning, I simply measured and marked the location for driving screws through the planking and into the chine. That evening, I “connected the dots” between these marks, giving me the line along which to drill the holes. The next day, I marked points along this line, spaced 3 inches apart. I drilled holes on a few of these points, and drove a few screws. The next day, I did a few more... and so on. 

Aft starboard side panel, dry-fit & screwed on.
Once the aft starboard side panel was screwed on, I trimmed the edges down some with a block plane. Then I went back and beveled the rims of the screw holes just enough so that I can drive the screw heads down flush with the plywood surface, while still achieving good compression of all the plywood layers beneath the screw heads.

Screws spaced 3" apart; Holes beveled for flush fit & layer compression.

At this point, the aft starboard side panel is screwed and fitted into place. I will have to wait until I have more free time to remove it, apply the epoxy, and then put it back on. In the meantime, I’ve resumed the fairing for the port side panel.

And, oh yes... Don’t think I’ve forgotten the Zip. I’ve assembled its breasthook & have been sanding the sides, as time permits.

Zip breasthook assembled & being sanded.

Monday, November 11, 2013

The Utility: Fitting the first planking panels

After a brief debate about whether to plank the transom first, or last, I eventually came to the conclusion that it’s a matter of individual preference. Other boatbuilders I trust kindly offered me their opinions, reasons, and techniques. I weighed all of their input before deciding on my own course of action.

I’m going to plank the sides first, and the transom second. That way, the aesthetics of the bright-finished transom should be consistent all the way out to the sides, with no end grain from the side planking visible.

Then I’m going to plank the bottom last. The reason for this basically boils down to ease of construction, regarding the transom. It seems to me that it will be easier to plank the transom while I can still access both inner and outer surfaces of it for clamping. I wouldn’t be able to do this after the bottom is planked. Since the lower edge of the transom will be underwater, then it won’t matter if the end grain is visible (whether or not it’s an aesthetic matter).

I started by cutting two 2’ x 4’ panels from a sheet of the Meranti. These will be the aft side panels. I clamped the first one into place on the starboard side. Then I roughly traced the trim line with a pencil, and removed the panel. I drew a second line 1” outside the trim line, so the panel would still be slightly oversized after I cut it. I cut it, and checked it against the port side. Since it looked good against the port side also, I used the cut piece as a template to trace out the second panel.

With both panels cut, I clamped them back into position. I’m very happy with the fitting on the starboard side. The port side still needs a little fairing, but it’s close.

Initial fitting of the aft starboard panel.

Aft starboard panel-to-transom fit. This gap will need to be filled in.

Aft starboard panel to frame #1 fit.

Aft starboard panel-to-transom inner fit.

Aft port panel-to-transom fit.

Aft port panel-to-sheer fit. This area needs a little more fairing.

Aft port panel-to-sheer fit, forward of frame #1. This area needs a little more fairing.

Thursday, November 7, 2013

The Utility: Trimming the floor battens

Some days you just don't have a lot of time to make any major progress. Still, there are usually some small things you can do to help the project along. Last night was just such an occasion. I took a few minutes to trim the forward tips of the outer floor battens. Now they match the inner battens, which I'd trimmed a while back. This will look much better than the squared ends once the bottom is planked.

Wednesday, November 6, 2013

The Utility: Preparing for Planking

A fellow boatbuilder pointed out to me that if I cover the transom first, before planking the sides and bottom of the boat, then the end grain of my planking is going to show around the rim of the transom. (Thanks Chris!) Of course, this only poses an issue if you plan on bright-finishing your transom, which is exactly what I’m planning to do. I’m planning to paint the rest of the hull. So, paint will cover the end grain of the transom as viewed from the side.

So now, my plan has changed to planking the sides and bottom of the boat first. The first pieces of planking that go on will be short 4’ aft sections on the sides. I will be butt-joining these pieces to longer 8’ pieces that will plank the forward sections on the sides. This will allow the butt joint to be located in the flatter aft section of the boat, which means it will be easier to do, and there will be less stress on the joint. I have to join the planking in sections like this, because plywood comes in standard 8’ lengths, and my boat is 11’ long.

In preparation for planking these aft sections, I’ve been sanding away dried runs of epoxy, etc from those parts of the boat I can’t easily get to once the planking is on. I’ve also worked to clean up the shape of the seat riser cutouts in frame #1. Still, before I can plank this aft section, I need to encapsulate these frame cutouts, as well as a couple of other places I won’t be able to reach once the planking is on.

Then, God willing, I should be able to begin planking the little boat.

Dried runs of epoxy have been sanded off of frame #1 and gussets. This is the starboard side.

Starboard frame #1 after sanding. The seat riser cutouts still need to be encapsulated with epoxy.

Port frame #1 after sanding.

Port frame #1 after sanding.

Port frame #1 after sanding.

The globs of epoxy are now sanded off of the transom.