Thursday, September 24, 2015

Casting a new handle for a bilge pump.

The cockpit sole is removable, but not easily, so the pump can't go on the sole, nor under it.

I need it somewhere I can get at it while sailing, so I can pump and sail. Ideally on either tack, but that's asking a lot.

And sadly I bought a whale urchin, without a removable handle.

The pump will sort of fit in under the benches, but the handle sticks out. The original handle comes across the body of the pump... Not the direction that I needed.

 Annoyingly the 2 pivots are different sizes, you can't reverse the handle.

But since I have a furnace for casting aluminium or bronze, I measured up and made a new pump handle. Obligatory warning here, liquid aluminium is going to mess you up something special if things go wrong. If you want to play with molten metal, you need to do a lot of learning. if at first you don't succeed, perhaps foundry work is not for you...

I used a hot wire cutter to make up the shape in expanded polystyrene (sorry no photo). This has a sprue of polystyrene attached, and it gets coated in plaster except for the very top. It's placed in sand with the sprue sticking out the top. You pour in the molten aluminium and it vaporises and replaces the polystyrene. Let it cool and you have an aluminium widget the exact shape of the polystyrene. I drilled holes for the pivots, and drilled and tapped a hole for the handle.
The handle is made of wood, with a 10 mm stainless bolt screwed up inside it with the had cut off afterwards. Drilling a 75 mm long hole up inside it is a bit fiddly.  I don't have a drill press so this was all done by eye.
The whipping helps reduce the chance of the handle splitting in use. The thread is 10 x 1.5mm so quite course, and it goes through 25 mm of aluminium, so it should be plenty strong. 

This is how it looks now.  I need to build a small platform under the seat to hold it just in the right place for the handle not to hit anything at either end of it's range.

If I polish it up, a lot of work, it will come out shiny and silky to the touch. I will probably get things working and then decide not to bother polishing it. A little metal paint may well suffice.

I could have bought a handle, and the pivot, but that would have cost silly money for something that I made up in an evening. Since it's solid aluminium, even with my less than perfect casting skills, it's vastly stronger than it needs to be.

It's not perfect, but it pumps just fine.

Sunday, September 06, 2015

Bits and pieces

I'm toying with the idea of remaking my mast. It's heavy and not quite straight. A birds mouth oval might be just the trick. Lighter, better looking, a diverting project.
On the other hand that does mean managing 20' long staves dripping in epoxy. And I have only got a small garden to work in.

In the mean time, I added a "Huntingford Helm Impeder" to The Lady Caroline. I have a simple loop in the cross string which I can pop over an aft cleat, and I can make the other end fast to the other aft cleat.  I now have 3 monkey fists hanging off or around my tiller.

  • The yellow will pull the rudder up. The basic design is here, page down a little.
  • The red will pull it down and lock it with a pop-cleat, so it will release if I ground it. 
  • The blue will tension the helm impeder so the tiller can stay put.

I also put together a couple of simple stands to go under the stern of the boat while she's on the trailer. These are simple A frames, with a hinged leg attached in the middle on one side. An eye bolt, some cord and a cleat prevents them from popping open on me. Some plywood pads spread the load. The pads are held in place with a simple rail screwed all around the underside. The rail allows them to be easily positions, but not to slide out.

With these under the stern, I can walk to right aft while TLC is on the trailer. That far back, gives me enough leverage to raise the mast by hand, instead of using an A-Frame and a block and tackle. This should take 10 to 15 minutes off rigging TLC. The simplicity of it also reduces the risk of the A frame slipping and the mast coming down with a bang.

I've looked really hard and I cannot see an easy way to add a way to row. The rowing seat would have to be on top of the Centreboard Case. I'm not sure that I want that amount of constantly changing stress there. Also, that would leave the block for the main sheet between my legs as I rowed.

I am thinking of trying a sculling oar instead. I am not quite the purist, and I'll use the outboard if need be, but if that were dead, having some sort of something would be nice. And it might be nice to have something less noisy for when there's not wind, and I'm not in much of a hurry.

And finally, I'm about 3/4 through the Lugworm Chronicles. This is about a couple who took their Drascombe lugger by trailer to Greece around 1970, spent the summer living on the boat as they sailed around Greece, then wintered there, to sail back to the UK. It really is quite incredible, especially given that they did this before you could simply pop into a ATM anywhere in the world, before you could ask google to translate everything, and before you could pop up a website to get a decent weather forecast in the language of your choice.
It's well written, albeit sometimes it does feel like you need an open map beside you as you read. I'd recommend it.