Archive for July, 2009

Footrest

Tuesday, July 21st, 2009

The backrest will help transfer some energy from paddle, through the body, and into the boat. A footrest helps even more.

footrestIt’s adjustable. The rail attached to the boat’s bottom has 5 10-24 nuts spaced along its length and epoxied into recesses. The footrest itself can be moved along the rail to the desired positioned and fastened down with the knob which, of course, holds a 10-24 threaded rod. Making it from white ash was straightforward. Drilling holes for fastening into the bottom of the boat offered a bit of tension.

This was the last structural component. Finishing is next.

Backrest

Monday, July 20th, 2009

The boat has no seat. The paddler sits on the bottom of the boat, or a cushion of some sort. I might do something about that later. There is, however, a back rest. One needs something to brace against paddling effort.

backrest shapingbackrestThe backrest is pretty simple, an 8-sided, tapered bar with a couple of curved pads. All parts are white ash. The pads were curved by boiling for a few minutes and then clamping over nicely curved surfaces, which just happened to be chair backs. The backrest rotates to provide a comfortable fit.

No mishaps with this component, except for losing one of the mounting screws. Time to listen to Beethoven’s Rage Over a Lost Screw.

Guards, Rails, Gunwales

Monday, July 20th, 2009

gunwalesThey have several different names. This boat’s designer called then guards. Others call them gunwales, or sometimes rails.

They weren’t hard to do. Many people like half rounds. The designer suggested half 8-sided because he has no router. Neither do I, and I like the looks of the half-8-sided.

These are made of Sitka spruce, absolutely delightful to shape. However, part of getting the right shape is getting the shape right. I’m fairly adept at planing something that is parallel to the bench top.

gunwales planing 1gunwales planing 2I’m not nearly as adept planing a 45 degree surface. After a bit of fumbling, I put a good 45 degree surface on a piece of poplar. It was then cut into about ten small chunks and glued with rubber cement to the qunwale. That positioned the workpiece for easier planing.  Pop off the props and refit for the opposite surface. Easy.

Attachment is with ring nails. Bedding is Dolfinite, a tan colored material with a consistency a bit stiffer than peanut butter. The only mishap was dropping one of the guards immediately after buttering it with Dolfinite. Of course, it hit the floor butter side down. Dolfinite cleans up rather easily with mineral spirits.

False Stems

Friday, July 17th, 2009

These were too easy. So, I had to make them harder.

The false stems are white ash, hard enough to be the boat’s shock absorbers. They are only about an inch thick, in either dimension, but are curved in almost all directions. Rough patterns made of thin plywood held up against the ends of the boat (one at each end) provided the initial cutting lines.

I thought they would be difficult to fit but was very pleasantly surprised. The trick is chalk. Coat the fixed surface with a heavy layer of chalk. Place the false stem piece against the chalked surface and wiggle back and forth. The transferred chalk marks the high spots. There might be only a few at the start. Remove them. Repeat until the fit is so good that the whole piece is covered with chalk. It goes a lot faster than I expected.

false stemBeveling comes after fitting. So, how do we hold the clumsy pieces? Some scrap stock screwed to the inside of the curve offers a lot of surface for the leg vice to hold. Beveling is also pretty quick work with a sharp spokeshave (Stanley #51, circa 1920) and a cabinet rasp.

So far, so easy.  Too easy. Can’t have that. Let’s make it a bit more difficult.

Harry Bryan called these boats “Fiddleheads” for some reason I don’t know. Why stick with the usual ogee curve found atop many stems? How about decorating the tops of the false stems with fiddleheads? Hmmm. Never carved one of those. Actually, I’ve never carved much of anything. Off to the world wide library to find some examples. …

stem fiddlehead 1stem fiddlehead 2Some basic carving chisels and some practice time on a scrap of ash led to the following conclusion. Don’t let anyone tell you that ash is good carving wood. The alternations of tight grain and loose grain may be great for shock absorption, but definitely not for carving. Yet, ash is what we want on the ends of the boat and the carvings will be what they are. Despite the less than optimal wood, I’m pleased with the results (which still need some final sanding). … Just don’t invite Stradivari to inspect.

Attachment is with four #8 x 1 and 1/4 inch screws for each end and the usual 5200 marine adhesive. The screws are deeply sunk with bungs to cover them.

Coaming

Wednesday, July 1st, 2009

Coamings are intended to reduce the amount of water that splashes into a boat. Done right, they also add a bit of aesthetic detail. Fitting the coamings is a fussy job. They’re such a point of visual interest that they need to be done carefully.

coaming showing gapsThe first step was planing the carlins with a bevel that causes the coaming to flare outward just a bit.

The next step was preparing the stock. These boards are just a bit thin of 3/16 inch, having been resawn from a very clear piece of white ash.

A double ended boat offers an additional fitting challenge. In many cases, the point where each coaming piece meets can be a simple miter joint. However fitting two precise miters, each meeting perfectly at each end of the cockpit, could be an exercise in frustration.

fit an inboard filler blockThe answer is simple, uses a few more steps, but is far less tedious than getting two compound miters, and the precise length between them, right.

Start off by getting the boards to fit nicely in the cockpit. They get screwed, but not glued, in place.  There’s no glue here to enable future repairs. The boards are be a bit short of full length, as shown in the first picture (click to enlarge). That’s OK.

Then shape a filler block that fills the last inch of the join. The bevels were fun! Wood moves. Resawing and thicknessing was done over several days. Each day found the boards in a different state of cupping and warping. After screwing in place, the were mostly flat, but held just enough cupping to make beveling the filler blocks “interesting.”

trim the endNext, whack off the end of the combined boards and filler block.

Carefully!

Don’t scar the decks.

Yep, tedious.

Really sharp chisels and careful paring help at the bottom of the cut.

coaming tipsThe last bit is a piece to cover the blunt cut. Some mahogany does the job and adds a tiny bit of accent.

Fair the edges, screw and glue the bits to each other (and not to the deck – repairability), stand back and admire.

Then do it all over again at the other end.