Sunday, March 17, 2013

Sunshine and Setbacks

It's been beautiful weather all week so we've been able to make good headway with the cap rails.  This is Duncan planing the tops flat as the toe rail changes angle all the way along the sweep of the boat.  I'm currently trying to figure out how not to waste too much teak when we cut the caps.  They are quite curved and so each length needs to be squeezed into the board next to another; flipping them over and staggering them to try to make it economical.  We're not going to have enough so it's another trip up to Houston to get teak and some more Sitka spruce for our spreaders Monday.

Quite a bit of time has been spent trying to find someone who wants to move the boat to the water.  It seems hiring a truck with a crane on it isn't an option around here, boat moving companies who have a suitable trailer are not local and therefore it isn't really worth their while getting over here just to do a 15 mile move and in any case they can't get the boat on their trailer so it means hiring a separate crane.  The quotes for the trailer moving 15 miles have been eye watering so far so we're still trying to work on persuading a local trucker to do it. 

The two options we had which meant we didn't need to hire a crane have now fallen flat (better that than the boat!) and so we're going to be sorting out the crane hire ourselves.  None of this has been as simple as it was when we moved my narrowboat "Seth" down the length of England; I called a company that the boatyard recommended, they went and collected it with their crane on the truck and they moved it to where we wanted it; surprisingly easy and not too dear.

We had a big setback with our new chainplates.  We were so pleased with how they came out; as soon as Duncan took over the cutting that is; I so wanted to do it but the fact is that he is MUCH better at cutting straight.

We took them all shinied and shaped down to Roger's friend Jason who owns a marine fabrication shop and who makes stainless chainplates amongst his big rails bending and welding work.  He said he didn't know if he would be able to do it as the Bronze was still about 7/16 and he knows that his machine can not bend 1/2 stainless.  He said he'd give it a go and let us know as he didn't do much work with bronze.

Next day we got the phone call.  Dunc said that's great and looked really happy so I breathed a sigh of relief and got on with my work.  Later I found out the sad truth.  Jason had managed to bend two fine (although his machine had found it hard) but then the next one had snapped.  He then tried heating it as it bent and that one snapped too.  Operation bend the bronze was very much on hold.

 We were really upset about it, not only because the bronze is expensive but also because it's so lovely and we really wanted to use it.  We went through lots of options and called lots of people and then went home to use the magic web to find out more about what went wrong. 

Our friend Steve sent us a link to a wooden boat forum page where several people had written about "annealing".  After further research on metalurgy and reading other forum conjecture we felt much more confident.  We also emailed and had a reply from Brion Toss a rigger who's book we are finding very helpful who said it shouldn't snap if you do it right and that aluminium bronze was a good choice.  Phew!

Moray at classic marine in Suffolk has been really helpful to us throughout our project supplying us with our Cranze Iron, bronze taps, making up all the mast fittings from our drawings (and suggesting some improvements) and knows a thing or two about bronze.  After a pleasant phone call with him we were really heartened.  He was sure we would be able to bend the bronze ourselves after we had annealed it and that you should never try to bend bronze without annealing it.  He said you have to get it really hot, but there is also an upper limit;

      'don't go putting it in a forge or anything!'

So we went back to Jason armed with all this information.  He was really happy to help us which was great as it must have been pretty traumatic seeing those pieces go.  We took some new pieces outside and started heating them with his oxy-acetylene torch.  It took longer than we thought, bearing in mind these things are super hot.  Jason kept looking at us;

    'do you think that's enough?  Thats quite a lot of heat guys...'

I wasn't sure and it was a little nerve wrecking but Dunc stood fast;

    'more heat'

Every few moments we questioned whether we'd done enough; not being sure how it would look, but Moray's words were in Duncan's head,

    'you'll know it when you see it; it's called sub-red'

and so the refrain went;

    'more heat'

And then suddenly it happened and we all went

'ahhh, that's it'

The bronze had been steadfastly black during all that heating and then suddenly it flushed a really dull red, as Jason moved the torch over it the area of red spread out.  We only heated the part that we were going to bend.  A job well done we left the pieces outside to cool.  People suggest several ways to cool the bronze but Moray said to just set it asside would be fine.  It seems other alloys sometimes need to be cooled quickly during annealing.

After leaving it for several hours to cool, Jason put the first piece in his brake press and we stood well back hoping for the best.  It bent straight to the setting with no fuss at all.  Jason said it was 100% easier and we all shook hands and congratulated ourselves and agreed we'd make up the two replacement parts before we come back to his shop to do all the rest at once.


No comments: