Sunday 27 March 2022

Centreboard | Installation

With the help of MVLW (My Very Lovely Wife) the centreboard was manoeuvred into position for a test fit.

It immediately became apparent that the pivot pin did not fit - it refused go through the hole in the centreboard.

A quick check with a square revealed that the pivot holes in the keel were not perpendicular, vertically or horizontally! I had drilled them by eye, so it was not entirely surprising.

I filled the holes with resin and re-drilled them with the drill guide clamped to the keel to ensure that the holes were properly aligned.

Here is an  M10 bolt passed through the keel to check it was true.

It was, so I refitted the pendant ready for installation. Here the tied and heat sealed knot sits snugly in its hole in the board. The pendant is 6mm Dyneema.

The board was reinstalled and the pivot pin was test fitted, as here.

The holes were lined up and true, but it was clear that the hole in the board itself needed to be reamed out a fraction for a good fit.

The board was then raised up and the hole enlarged very slightly in situ with a rasp, like this.

The pivot pin was then successfully fitted, like this.

And lastly the pin was sealed in place with thickened epoxy resin, as here.

The resin was held in place with tape while it cured.

That was a lot of drama, but all is well that ends well!

Hull Side Panels | Finishing The Finish - Again!

I stated in a previous post that I was not entirely happy with the blue hull side panels. There was a 3" wide strip of dull paint all along the panel, next to the white stripe.

It isn't clear to me how it happened, but this was the strip not masked off and covered to protect the sides from the mess entailed in wet sanding. I must have spoiled the surface somehow when finishing the white stripe.

There were also a few light patches where there was insufficient depth of paint, despite the six coats of gloss that had been applied.

I decided to just leave it for a while, to see if I could live with it. As I suspected, I couldn't.

So I masked off the white bottom panels and boot top stripe, and wet sanded the blue side panels and boot top stripe with a P800 grit.

Five more coats of gloss were then applied to obtain a good depth of colour with no dull or light patches.

Finally I wet sanded the blue with P800, P1500, P2000 and P2500 wet and dry paper before finishing with P5000, P9000 and P11000 polishing compound and the rotary sander.

This is what it looked like.

It was a massive amount of work but I was now sure that the sides would stand close scrutiny. The depth of colour is good and the surface is like glass. Very nice.

But I wouldn't care to do it again!

It was now time to start on the transom. I am copying the paint scheme on the prototype PocketShip, so there will a boot top stripe across the transom and a frame up the sides. The transom itself will be finished bright with varnish.

I started by masking off the transom and painting the blue stripe, as here.

This is going to take a long time!

Sunday 6 March 2022

Centreboard | Fishing For The Pendant

We need to thread a line through the pendant hole in the cockpit and around the sheave in the centreboard trunk and up through the bottom of the boat.

We need this to pull the centreboard pendant through to the cockpit when we install the board.

I thought this would be tricky but it turned out to be very easy.

I made a small loop in the end of a length of thin and flexible garden wire, like this.

I threaded the wire into the trunk from the cockpit and through the sheave.

Then I made a small hook in the end of a piece of stiff wire, like this.

This was lowered into the trunk and hooked into the loop in the garden wire and pulled through the centreboard slot at the first attempt. Easy!

I then taped some thin line to the garden wire and pulled it through, making it fast with a piece of cardboard so it could not fall back into the trunk. As here.

That was fun!

Centreboard | Making The Pivot Pin

It was time to make a pivot pin for the centreboard in anticipation of its installation.

I had obtained a long M10 A4 grade stainless steel bolt for this purpose.

Here I am cutting the bolt to make a pin 1 3/4" long.

A good bimetal blade made short work of the bolt.

This is the pin itself.

And here it is test fitted in the keel.

That was fun!

Centreboard | Drilling For The Pivot Pin

The build manual tells us to make the centreboard pivot pin from 9mm stainless steel rod or a bolt.

Investigations revealed that there is no such thing! From M6 upwards bolt sizes increase in 2mm increments, so I had the choice of M8 or M10.

M8 was far too loose so I decided to drill the pivot holes out to 10mm.

Here I am drilling out the centreboard hole.

And here is the pivot hole in the keel, masked off and sanded to show the epoxy liner in the hole.

The hardware pack includes some M10 threaded rod to make the pivots, but I didn't think that  would be a good idea for the centreboard.

Over time the thread would chew up the board, so I purchased a long partly threaded M10 bolt to make the pin.

Here is a test fit for the bolt.

It was a perfect sliding fit. Very satisfying!

Centreboard | Rework & Repaint

I had set the centreboard to one side while I painted the hull and when I returned to it to finish it off I immediately realised that compared to the hull it was of quite a poor standard.

Clearly my painting skills had improved a lot since my first attempts on the centreboard!

No problem. I sanded the board back to a P220 finish, like this.

Three coats of primer followed, as here.

I was able to paint both sides at the same time by using these Paint Points to support the board.

The primer was sanded again to a P220 finish.

I applied four coats of gloss with a good brush rather than waste a roller, and when hard I wet sanded the board with P800 through to P2500 grits. Like this.

Lastly I used Festool polishing compounds to polish from a P5000 to a P11000 finish. The board was now perfectly flat, and smooth as glass! Like this.

That will slip through the water very nicely.

Hull Side Panels | Glossing And Finishing The White Stripe

It was time to finish painting the white boot top stripe.

First I masked off the hull sides and sanded the white primer with P220 grit, and applied the first coat of gloss.

It looked like this.

In all I applied six coats of gloss to the white stripe. This was the result.

When dry I pulled the masking tape and wet sanded the stripe with P800 grit. As here.

It looked really good, with a sharp edge and no bleeding.

Then I wet sanded with P1500, P2000 and P2500 grits. I found that wet sanding is a lot easier when using a decent spray bottle to wet the surface.

Lastly I polished the stripe using the Festool P5000, P9000 and P11000 polisher and compounds.

It looked like this.

Note that I masked off the side panels to protect them from mess when wet sanding. However, I didn't mask right up to the stripe, which turned out to be a problem.

Finally I pulled the tape and the masking, as here.

I found that the area of the side panels not covered by the masking was duller than the rest of the hull side. I must have sanded or polished it too much.

There was a dull band on each blue side all along the edge of the white stripe, which I was not able to polish out.

You can't see it in the pic but it is really obvious when standing next to the boat.

Oh dear. I can see rework coming my way ...

Hull Side Panels | Finishing The Finish

I wanted to get a really good finish on the blue hull sides so I employed the same methods used on the bottom.

First I wet sanded both sides with P800 wet and dry. Here is the starboard side.

Then I did the same again using P1500, P2000 and P2500 wet and dry paper. This is the port side.

Lastly I used the Rotex 90 in rotary mode to polish the surfaces.

This is the sander using a medium P5000 (red) polisher and compound.

Then we use a fine P9000 (blue) compound and an extra-fine P11000 (white) compound to complete the finish. Here they are.

This was the result on the starboard side at the stem.

It's beautifully smooth but like the bottom I'm not too impressed with its shine or depth of colour.

I will live with it for a while and see how I feel about it ...

Hull Side Panels | Priming The White Stripe

I thought that it would be wise to use white primer over the light grey primer on the hull side panels, to be sure that the white stripe would be same shade as the bottom.

Here I have masked off the white stripe and applied a coat of white primer.

I think that should look nice when painted!

Hull Bottom Panels | Finishing The Finish

I decided to aim for a better finish on the bottom panels, not because they would be on show but because I wanted to practice before tackling the topsides at some future date.

Accordingly I invested in some wet and dry sandpaper and a set of polishing attachments and compounds for the Rotex 90 sander.

First I pulled the masking tape on the blue stripe.

Then I wet sanded the bottom panels with P800 through to P2500 grits.

Lastly I polished the panels with Festool polishing compounds from P5000 through to P11000.

This was the result.

The surface is now beautifully smooth - like glass - but it isn't as shiny as I had hoped.

I will no doubt find a way of improving the lustre at some point, not that it matters on the unseen bottom panels which will in any case get scraped and scratched in use.

We're getting there, slowly but surely!

Hull Side Panels | More Gloss

When the Hempel filler had cured I sanded the affected surfaces flat with a P220 grit and applied four more coats of paint.

This is the paint I am using. The colour is Oxford Blue, appropriately enough!

I used this roller and a foam brush for tipping out.

I left the paint to fully harden for a couple of days and then sanded the surface with a P280 grit to get a nice flat surface. As here.

Lastly I applied a sixth coat of gloss, hoping it would be the last. This was the result.

Looking good!

When the paint was dry I pulled the masking tape on the stripes, as here.

It left a lovely sharp edge with no bleeding. This 3M tape is excellent stuff!

Hull Side Panels | Gloss Paint & Bubbles

I masked off the white boot top stripe and applied the first coat of blue gloss to the sides, using a 4" roller and a foam brush for tipping out.

Not surprisingly it looked pretty patchy, as in this view from astern.

The following day I was slightly dismayed to find that a number of tiny bubbles had formed as the paint dried overnight. I had no idea why and didn't spend any time worrying about it.

This is what the surface now looked like, in some places.

That would not do at all! So I carefully ground out the bubbles with a fine carbide burr in my small cordless drill, and filled them all with Hempel Profair filler.

This is how it looked.

Not pretty, I know, but I was sure that subsequent coats of gloss would cover it all up nicely.

Onwards and upwards!

Boot Top | Marking Up

I decided at the start of the build that I wanted PocketShip to have a handsome boot top stripe, like the prototype.

It's a lot of trouble to do properly and some builders don't bother, but I thought it was worth the effort.

The first step was to determine how wide the white stripe on the blue side panels should be, and how far down the sides it should be located.

After consulting lots of of photos I concluded that the stripe should be about 38mm from the edge of the white bottom section at midships.

I used the laser level to mark up the top edge of the stripe, and then adjusted the bottom edge until it landed fairly at the stem and stern as shown in various builders' pics.

This is what the white stripe looked like when pencilled in half way along the hull. 

Here is what it looked like at the stem.

And this is what it looked like where it crossed the chine and ran along the bottom panels to the transom.

I adjusted the edges fractionally at the bow and stern to make sure they landed in exactly the same place on both sides of the hull.

Lastly I used the laser level to ensure that all was level and straight across the transom, like this.

Notice how the stripe varies in width depending on the angle of the side or bottom panel, being exactly level itself from stem to stern.

I think that will look really nice. I'm happy with that!

Hull Side Panels | Sanding

When the primer had hardened I sanded both side panels to a flat, smooth finish using a P220 grit.

They looked like this.

Looking nice!