More on Bulkheads

I seem to be stuck on bulkheads but over the last couple of days the inside of the boat has started to come together. Making up the bulkheads on the bench seened to take a long time but once they are complete putting them in the boat has been very quick and easy. Putting the bare plywood bulkhead into the boat and then adding all the stringers to them would have been more difficult and I think it would have taken longer.

This is what the bulkhead looks like when it is being glued together on the bench.

 

Here it has been cleaned up and is in position in the boat for the glue lines to be marked out and taped. I was sceptical about the tape but it really does help to keep the epoxy under control.

 

 

 

This is what the tape looks like. The next step is to prime the glue line and the edges of the bulkhead with unthickened epoxy and leave it to soak in for a while. Then thickened epoxy is applied liberally between the lines of tape. What I'm trying to do is to ensure that the gap between the hull and the bulkhead is full of epoxy.

 





 

The next photo shows two of the four bulkheads in place. These bulkheads support the cross seat and brace the centre board case.

 

 

 



Today the second pair of bulkheads were installed in the boat. In between cleaning them up, taping and gluing them in I made templates for the aft side seat fronts and cut the ply panels. This last photo shows the state of play at the end of today's work.

 

 

There will have to be a pause in procedings because I have run out of ply and need to buy more (that can't be done at Easter!). Until then there is the supporting beams for the aft side seat tops to work on, more than enough to keep me busy until the shops open again.

 

Ballast Tank Bulkheads

Before I get on to the ballast tanks here is a photo of the box that supports the mizzen mast. It is now glued in place but still has to have epoxy fillets run around the joints. The box is sealed at the bottom and any water that gets into it drains out through a hole in the transom.

I seem to be making very slow progress on the ballast tank bulkheads. There are two short ones at either end of the centreboard case and two taller ones that support the cross thwart. All four bulkheads have stringers glued to them to support the tops of the ballast tank compartments. When the bulkheads are in place the stringers have to be level so the top of the tank is flat. I decided to fit the stringers to the bulkheads on the bench because this is much easier and cleaner that glueing them to the bulkheads in the boat. The measuring and marking the position of the stringers has to be done in the boat and is awkward to do.

Here is a photo showing the two short bulkheads, one glued in place the other waining for the glue to set. The tops of these two bulkheads have to be level across the boat and also fore and aft. The stringers on the two intermediate bulkheads also have to be at the same level and so they can only be positioned when the first two are in place.

 

Here is the template for the big bulkhead that forms the forward buoyance and storage compartment. The template is made from the building mould with short pieces of scrap ply hot melt glued to it to get the exact shape. I cut the centre out of the mould to lighten it.

Stern Buoyancy/Storage Compartment

After turning the boat over the frame was removed and the boat set up on blocks so that it is well supported and level both fore and aft and across the beam. The next job was the tedious one of cleaning off the squeezed out epoxy from the plank laps on the inside. Some of the squeeze out I had removed once the plank was in place but there were places that I couldn't reach and bits I had simply missed.

With the hull cleaned up I started on the buoyancy and storage  compartment in the stern of the boat. I used the building frame as a template with short pieces of scrap ply attached to make an exact fit with the inside of the hull. Here is a photo of the completed template still in the boat.

 

Several more jobs had to be done before the new bulkhead could be glued in place. A rail was fitted to the transom to support the rear edge of the top of this compartment and another rail was glued to the top of the new bulkhead to support the front edge. The position of the box that supports the foot of the mizzen mast was marked. In the next photo the new bulkhead is glued in place; the 4 strips are scrap ply braces to hold in in position while the glue sets.

 

In between the cutting and shaping of the template and the new bulkhead I made up the box that holds the foot of the mizzen mast. This is a simple box, 4 sides and a bottom but I found it quite tricky to make. The plywood sides need to be shaped to fit the bottom planks of the hull. The front, back and bottom of the box are solid timber. I glued the five pieces together 2 at a time. First the front and bottom. Then the ply sides, one to the front and one to the back. Then finally the last 2 sections were glued together as shown in the following photo. It is hard to see the box past all the clamps holding it together. The last sections of the box were given 3 coats of epoxy before the final gluing and the inside of the box will be painted before the top is fixed on the compartment. Once the top goes on the inside of this box will be inaccessible.

 

Because water can get into the box around the mizzen mast there has to be a drain hole through the transom. The hole can just be seen in the photo above, towards the top left of the hatch opening - click on the photo to enlarge it. Like the ballast tank holes in the bottom of the boat, described in an earlier post, this hole has a plastic sleeve epoxied in the hole. This sleeve will protect the edges of the hole and provide a better seal of the endgrain inside the hole.

 

The last of today's photos shows the template for the next bulkhead working forwards. This bulkhead is in 2 halves separated by the centreboard case and, together with another similar pair of bulkheads about 400 mm forther forward provides the vertical faces of a compartment that stretches across the boat.

Turning Over Ceremony

Today was the big day! My Able is now the right way up. I rounded up 8 volunteers from the Queensland Wooden Boat Association plus my daughter and son in law. Thanks to all of you for making the effort to come and help. I hardly needed to take part and also had a photographer. Here is how it went.

Still in the shed with wheels fitted to corners of frame. Ready to go.

 

Out on the grass, wheels on the low side have been removed and added to the top of the frame on the high side. The frame is propped up while the other pair of wheels are removed.

 

Starting the lift towards the vertical.

 

Almost up to the halfway point.

 

Halfway point.

 

On the way down. Gently lowered onto the wheels.

 

Back on the wheels on one side.

 

 

Tipped up with frame on saw horses while the second pair of wheels were added. After the boat had rolled over through 180 degrees it was displaced sideways by almost 4 metres. This photo was taken after we lifted the whole thing up and moved it sideways to line up roughly with the space in the shed.

 

Back in the shed. Thanks again to the volunteers who made it so easy.