A word of warning before starting a project like this. You won't sleep much. You will have trouble dropping off to sleep while your brain runs through the problems with the plan for the kitchen/bathroom/whatever you were thinking about earlier. I am sure the professionals don't have this problem, given they have done loads of boat builds, but also because they are specialists.

For example, I am going to install the sewage treatment plant under the steel floor of the the skipper's quarters. This is also where the prop shaft runs and which currently houses a large concrete lined water tank. As you can see from the photo, it's a large-ish space but certainly no St Paul's cathedral.

So I went down into the bowels of the ship this morning and took some measurements and photos. There are a few spots of seriously flaky rust, predominantly where previous pipework had pierced the steel floor and then been pulled out and left, leaving a gaping metal sore for the rust to grab hold of. So here was my thought process in the few minutes I was there...

Ok so it's big enough for the sewage plant but I need to cut through the steel with the plasma. What's the flash point of 2 stroke diesel oil which is sitting in the bilge and finely coating some of the metalwork? That could cause snags. Should I blank off areas with heatproof shields? Where do I get heat proof blankets? Are they even a thing? How do I remove the steel tank with concrete on the inside? Beat the crap out of it and then cut it into section with the plasma? Is it providing any structural support for the floor of the cabin? What welding rods do I use on the steel floor? 6013 or low hydrogen 7013s or another grade? What amperage do I need? What's the danger of it blowing through? Should I start large or small rod? Multiple pass? Where are the pipes going to run? It needs to be below the level of all the inputs by at least a 1:100 gradient. Do I fit the sewage system lengthways of sideways? I am most likely to get more roll that pitch so lengthways makes sense, but that's going to be harder to construct the cradle. What do I do about ventilation whilst welding? Ventilated mask? Bigger hole in the floor?...

Aaaaaand you get the idea. This was only a fraction of the conversation I had in my mind about this job. The carpenters and welders who work on these boats all year round know their stuff inside out, of that there is no doubt, but they only do one job, perhaps with a little crossover to other trades. When you are trying to ensure that the plumbing, electrical, mechanical, metalwork and carpentry all function correctly and are aesthetically pleasing and you keep yourself safe (and financially solvent) is a big ask. If you are considering a barge renovation and you don't know what a 6013 rod is, what the optimal sewage fall angle is, Ah ratings for batteries or if these things are of no interest to you then you either have to learn or pay someone. You could pay someone to do all this stuff. This week would have cost me about €1500 for a carpenter to do what I did, probably a bit faster but that's a big bill whichever way you look at it. If it's not striking you as a big bill I suggest you look at Will Trickett's barges and buy new... Since we don't have the budget for Mr Trickett or to pay someone, in short, I have to know my $hit.

It is the end of a very long 9 day stint on board. Hard work, frustrating, cold and miserable at times, but rewarding. Every day I spend on "Zee" I learn more and understand what works and what doesn't. But don't get me wrong, this is not for the feint hearted...