Paddle Cad 2

I should have done this at the start. Having a full size smooth symmetrical plan of your paddle is the only way to do this.

So if my Ash ever turns up at the sawmill then I'll use these to make the some nice paddles.

Surface Fairing 2

Popped into the garage today, and checked out my surface filling from the other day. Where I'd used filler to cover blemishes, it sanded off totally smooth and perfect, to the extent I couldn't see or feel the edge of 100mm glass tape anymore.

I realise that I am going to have to do the same on the inside, which will take a couple of days. But, I like the idea of making the dimples and blemishes disappear, so it has to be done.

Paddle Cad

My paddle book has some measurements for a selection of paddle blades. The official method is to measure the elevations onto a piece of ply, then use a French curve to make a nice curvy shape. This gives the shape of half the paddle on the plywood. Cut the ply to get a half template, and then mark around the template onto the paddle blank twice to get the complete shape.

The trouble is, I found this wasn't very accurate, and my first paddle was slightly out because it was impossible to line up the template exactly symmetrical to the first side when marking out the second side.

(The image to the left has some pixellation which is why it doesn't look quite symmetrical, but printed full size, it is.)



Making a full template was slightly out too, because it was impossible to link up the marked-out points with the french curve accurately enough on the different sides of the template.

The solution was Turbo CAD.

This CAD package allowed me to mark out the template lines, and then link the ends of the template lines using a bezier or spline curve. Using the snap facility of the package, the curve is snapped to the ends of the template lines. The spline or Bezier algorithm gives the right shape. Because its a CAD package, it comes out perfectly symmetrical.

Print it out at 1:1 onto about 3 sheets of A4 and voila, a full size symetrical paddle template.

Hopefully this will translate to a symmetrical plywood template and a perfectly symmetrical paddle.

Surface fairing

This has to be the dullest part of the build. I spent a day sanding the hulll inside and out. Then I spent another day with the epoxy filler filling in everything that didn't seem flat, such as the slight dimples in the fibreglass bandage.

It was pretty neat sanding the decks though and grading them into the gunwales. She looks smooth and sweet now.

Should only take another hour to sand all the filler back and then I'll be ready to fit the seat bars and paint.

Paddle 2

This is the handle after shaping it first with the belt sander, then with sandpaper. I am impressed with it anyhow. I also don't know how I ever managed without a belt sander until now.

Paddle 1

This is the second paddle, composed from nine pieces of wood! Note the staples that stop the blades sliding when I tighten the cramps.

Seats part 1

The seats have been exercising me, but this is the solution I chose.

The wooden battens are 600mm long, and shaped to fit inside the hull. I'll screw and fillet them to the insides of the hull.

600mm allows me to vary the seat position fore and aft.

The glass reinforcement should stop the battens from splitting. The excess glass will be trimmed before fitting.

Details

I added a piece of 15mm copper pipe for the painter, and the M6 A4 stainless steel stud poking out of the bow will have a ring on it.

There's a wedge of wood glassed in behind the stud, and a nut on the end if it. Hopefully it will be strong enough.

The clamps are holding the deck in place while the glue dries.

Glassing my bottom

Next step is to glass the underside of the hull for strength and abrasion resistance.

I am rather pleased with the result.

The woven glass mat is easy enough to work with, using a mini paint roller, and working my way from one end to the other, it was easy enough to wet out the fabric and make a really neat job.

The excess mat will be cut off later.

Filleting & Taping

All the internal joints must be filleted.

The filleting material is epoxy resin mixed with wood flour (fine sawdust) and colloidal silica.

This forms an epoxy paste that in turns forms a rock solid joint in the hull.

Once the filleting epoxy has gone tacky, all the internal and external joints are taped with 100mm glass fibre tape set in epoxy. I found it easiest to paint some epoxy on, lay the tape in, then wet it out with the brush. All the crinkles disappear once you've completed the job. Marking a line 50mm from the joint helps give a neat edge to the tape.

Hull Assembly

Suddenly she looks like a canoe!

The hull is assembled using cable ties prior to filleting. The spirit levels ensure there is no twist in the hull.

Annoyingly the scarf joint on the starboard gunwhale near the bow has cracked and will need repairing.

4:1 scarf joints weren't enough.