Captain’s log
Dateline: 21.08.2022
North Captiva
Got invited to go along with a bunch of friends to North Captiva on a 27’ power catamaran. Helped me get a better idea of what’s gonna be in my way when I take Curious Cat out of Dawson Canal the rest of the way.
Many areas around here have less than 4’ of depth, a couple of spots are only 2’ deep in high tide — all that makes it extremely hard for my cat with almost 4’ of draft to find her way out into the ocean. I’m likely going to Charlestown, SC next, to avoid storms and get some place to dock and continue working on my boat, but first need to get out of Florida.
My friends gave me a tour of the island on their awesome little golf cart. North Captiva is a very interesting place, there’re almost no gasoline cars in there, 99% of vehicles are golf carts. There’s a landing strip for small personal aircrafts, and basically lots of rich folks own houses there that they rent out to yuppies. That’s also the downside of the place, the crowd is extremely transitory, young, loaded with their parents’ money, and usually drunk. On the bright side, lots of beautiful houses and exceptionally clean air. The only way to get there is by plane or boat, and they get groceries delivered to them by boats, trash is taken out on a small barge. Tons of gopher turtles, I picked one small guy up, it started hissing at me, I put it back down, and then I fed it some leaves, very lovely little animals.
About a hundred years ago a big storm has split that island into North Captiva and Captiva, basically washed away huge part of land. Very unique place, too bad it’s very shallow around it, not for big boats.
Washers for solar MPPT charge controllers
Mounting those Victron charge controllers is a whole story. The current situation is that I’m putting them temporarily inside the cabin, until my diesel engine, hydraulics, and genset are replaced with a bunch of LiFePo4 batteries in the engine room and I’m able to finally move most if not all of my electronics there, all being neatly ordered and safely mounted, protected from lightning, moisture, thieves.
But now is now, I have to mount them close to my AGM batteries, so that the battery bank remains charged. Function over form.
The mounting cutouts on radiators are about 8mm in diameter, and the amount of room for washers above those slots is somewhere close to 14mm. It doesn’t have to be precise, but I’m probably not going to just use whatever washers I find in one of my little plastic bags, and get carbon fiber washers instead to protect the anodization/paint on those radiators — I don’t want to scratch them in case I’ll have to sell those soon for any reason, plus composite washers are lighter and usually not (as) conductive.
From the chart on this page, M6 seems to make the most sense. I’ll need some kind of short M6 screws or bolts for those, they’re probably just gonna be stainless steel, imperial size, bought from one of the local stores. Ideally I should go with bolts that have no thread where they touch the radiators, and hold those with locking nuts from the other side of the honeycomb wall. But whatever I get, as long as they hold my MPPT charge controllers in one place and don’t leave scratches on the aluminum radiators, I’m gonna feel accomplished.
The current level of charge is at below 11 Volts, and it should be over 14. My VHF radio plainly refuses to work with the voltage being this low, and I have no cord connected to the shore to charge the boat. Not the most responsible person, I know, but I had other stuff to do. Lots of other stuff to do — the boat wasn’t able to move and almost none of the bilge pumps were working. At least I have my excuses ready.
In all honesty, I’m getting composite washers instead of 316 or aluminum primarily to see how strong those are, maybe will replace most of stainless ones I find on the boat with carbon, should save some weight. Or at least go with aluminum, hastelloy, or titanium. Stainless is nice and all, but very heavy, and it all adds up.
I hate imperial. Metric is just so much cleaner and easier to read, write, memorize, calculate. I swear I will replace everything with metric on this boat. Really dislike feet and inches, not to mention all those 5/16" and 4’ 2" measurements, it’s just so much more ugly, less usable, and less precise.
Bolts and nuts come in nylon and polypropylene, but those both are plastics and aren’t really that strong. Polypropylene is supposedly stronger than nylon, but becomes less stable at only 80°C, could in theory be achieved by those radiators on a hot day. Aside from material’s strength, I don’t want to inhale whatever fumes those plastics emit even if they don’t melt — this is not for mounting wires after all, radiators are meant to get hot. Hence I’ve decided to go with titanium.
Those M6 washers are 1.5mm thick, the radiator is about 3.5mm thick, and those honeycombs I’m mounting the whole thing onto are about 18mm thick. If we assume I’ll need washers on the other side, and possibly washers between radiators and honeycombs, then it’s 1.5mm + 3.5mm + 1.5mm + 18mm + 1.5mm = 26mm, and then some length needs to be left for the nut, even more in case I go with locking nuts. This locking nut is almost 8mm long, means the minimum screw or bolt length I need would be 26mm + 8mm = 34mm. Luckily, these exist. The bad news is that it’s over $7 per screw, the good news is today is the first day of the rest of my life and hence why not splurge on some fancy scews. 40mm is when Allied Titanium’s socket head cap screws lose full length thread, so couldn’t go with their 35mm, Can always make it shorter later, but who knows what else I’m gonna use that screw for in the future, extra 5mm of length won’t hurt.