Wednesday, 3 February 2021

Bowsprit | Making The Balk

While the rudder was glued up and curing I moved on to making the bowsprit.

This looked like an interesting project, and would be the first of the boat's spars.

The bowsprit is manufactured from a solid piece of timber, made of two lengths of 2 1/2" by 1 1/2" Douglas Fir laminated together to form a 2 1/2" by 3" balk.

So the first step is to glue the two pieces together. As here, on the bench.


Having used most of my G cramps on the rudder I had to search out any other clamps I had for use on the bowsprit.

I found a pair of enormous 10" G cramps which I purchased online some time ago and had forgotten about.

They were much larger than I needed, but I kept them anyway thinking they would be useful one day.

Today was their day.


Rudder | Gluing The Cheek Pieces

The cheeks of the rudder are made from two pieces of 9mm ply on each side, glued together to make a chunky 18mm cheek.

In the build manual they are installed all at once, and then a router is used to chamfer the edges.

I could not see how I could chamfer the cheeks where they are flush against the rudder blade, so I decided to make and chamfer them before installation.

The first step is to glue the parts together, to make the two cheeks.

Here is one cheek, clamped up and curing.


  That's it for now!


Rudder | The Rebuild

The day after I discovered that the rudder was effectively scrap I devised a plan to restore it to become a functional part of the boat.

The only bits that were wrongly installed were the rear and bottom blocking pieces. Everything else was fine.

So those pieces had to be replaced.

It shouldn't be too much of an issue.

When I started researching PocketShip I read on one builder's blog that he built a curve into his keel and resolved it by cutting the keel in half along its entire length and then realigning it. Compared to that a dodgy rudder is a piece of cake!

So, the misaligned blocking had to come out.

First, the bottom blocking was removed. I drilled a hole at both ends, as here.


Then the jig saw was used to cut the blocking out, like this.


The rear blocking was removed by drilling holes at short intervals and cutting it out piece by piece with the Japanese keyhole and rip cut saws. Like this.


I found that the spring clamps had not been very effective and one side of the rudder was only partly fixed in place. So a good thing that I was rebuilding it, then!

Then the inside of the rudder sides were carefully cleaned up with a chisel and mallet.

Here is a view of the rudder interior, held open with a wedge of scrap.


Now I made new blocking pieces.

Here is the bottom blocking being planed to profile in the vice.


And here is a test fit of the new blocking pieces.


In the above photo you can see that I have fitted a cord strung between two tacks along the length of the bottom and forward blocking, so I can line it up with the pencilled-in centre line on the blocking itself.

This will make sure that the rudder is correctly aligned when glued up.

Here is a close up of the cord and the centre line.


This is what I should have done in the first place.

If you're building a PocketShip and haven't built your rudder yet - don't do what the manual says.

Fit the front and top blocking first, clamped to the bench to make sure it's straight.

Then put it in the vice and do as I did here to ensure the aerofoil profile is accurate.

Lastly, here is the rudder glued up and curing.


This time I used plenty of G cramps to make sure the joins are good and tight, with some spring clamps to provide supporting pressure.

That was a lot of work, and I'm happy to have that episode behind me.


Rudder | Eighth Cock Up!

I left the glued-up rudder to cure for a couple of days before removing the clamps and examining my handiwork.

I was immediately concerned at what I saw.

In short, the rudder blade was curved on one side, and straight on the other.

In other words, it was bent.

Here it is held upright in the vice, for appraisal.


For a split second I thought that perhaps it would not make much, if any, difference to the performance of the boat.

Then for another split second I thought that maybe it would not even be noticeable.

Then reality kicked in and I knew that I would have to remake it. It's not right and there is no way that this can be part of my boat. There is no doubt that this qualifies as a fully fledged Cock Up.

So I didn't do anything. I let it be while I considered how to correct the situation.

On reflection, I was foolish to simply glue the sides and the blocking together, and assume that they would acquire the required aerofoil profile all by themselves. Why would they?

I even made it worse by using wires to stop the blocking from sliding around.

When making the keel I had previously had a similar moment.

To make sure that the keel was straight I marked in the centre line and used a line strung between the front and rear of the keel to make sure it was exactly aligned.

That is what I should have done with the rudder.

So, more work required on the rudder ...


Companionway Hood & Slide | More Clear Coating

While the rudder was curing and the epoxy was in use, I clear coated the inside faces of the companionway hood and slide.

Here is the hood interior.


And here is the slide.


Not visually exciting, but important progress!


Rudder | Test Assembly & Gluing Up

All the pieces of the rudder were made so a dry test assembly was in order.

Here is what it looked like.


That looked good, so I went ahead with gluing it all together. As here.


The spring clamps held the sides in place except where they made the transition from a full width to a narrow trailing edge. A G cramp was required there to hold the sides down to the blocking.

As suggested in the build manual, I drilled a hole through the trailing edge and used a piece of wire to stop the blocking sliding inside the rudder. Here it is.


We are getting there!


Rudder | Making Blocking For The Cheeks

The blocking in the centre of the rudder butts up against the front blocking and makes the top section solid and very strong.

This is also where the cheeks will be fitted, giving more strength to handle the torque from the tiller and the rudder itself.

The lower, rear area of the cheeks blocking is chamfered where the side panels will curve to the trailing edge, giving the necessary aerofoil profile.

This required a bit of thought and practice on some scrap ply to make a test piece. Here it is.


You can see how the profile changes from the front to the rear of the blocking.

A dry test assembly then followed, like this.


It all seemed to fit together as intended. Here is a closer look at how the test piece fitted.


Happy with this I then marked up the blocking on the edge-glued piece of Ash, as here.


Having cut it out I then scribed in the line for the chamfer, using one of the cheek pieces as a pattern. Like this.


The chamfer was made using the rotary sander and a P40 grit to grind the blocking to shape.

This is the finished piece in a test fit with the rest of the blocking.


So far, so good! Next step is final assembly.