Midwinter calling, day 48

Copper exercise

The rain gauge is attached to the side of the roof over the passage to the pavilion so it is free but can still be taken down and emptied after reading.

The wind vane was not difficult to make either, but was complicated by the fact that I wanted some kind of wind speed measurement that can be easily reproduced and give the same measurement in other locations. So it must be easily 'calibrated' and must not be too advanced, require electricity or clocks, which frankly was a big problem. The normal anemometers I could think of with three rotating hemispheres, the vane with a propeller etc, are all electricity and time based, or could work like a car's speedometer with magnetic coupling to a spring-loaded metal cup with a coil spring as resistance. I considered one that uses the pressure difference against and with the wind, but decided to wait with that. In the end I had to choose what I least wanted, which is a plate at the end of an arm that is suspended at the top. The stronger the wind, the more the plate is pushed back. But, if it is recreated with the same dimensions, specific weight and balance, it should give a certain angle at a certain wind, even if I don't know what that wind speed is in meter per second. The anemometer will not be that accurate, especially not in light or very strong wind or highly variable wind, but it at least gives the opportunity to measure the wind with hopefully decent repeatability.

So the wind vane is made of brass. An arrow pointing in the direction of the wind and with a 30cm large third of a circle in the other direction, with small cuts along the circle sections outer rim to mark degrees. Wind make the hanging plate deflect back, and the cuts are used to read the angle, and an extension and end stop prevents the wind plate from flying off, and there is a small spring at both ends to prevent the wind plate from hitting too hard. I don't want something making a lot of metallic noise. I just hope I made the plate in the right-ish weight, but I'll probably have to adjust the weight once we've gathered data and I have better measurements. The entire device is simply threaded onto a brass shaft mount with compass directions and pinned in place. It can rotate very freely which is the important part and just to be safe I have put some oil on the moving parts, which have been given some protection to prevent rain and ice forming on the shaft.

Hrappr climbs onto the top of the pavilion roof and nails it in place, just like the rain gauge mount. The wind vane is visible from inside my workshop window or the guards attic window, and the graduated direction ring at the bottom gives direction. I probably should have made the scale bigger, but it is as it is. It looked big on my workbench.

My sambos and most of the staff are gathered as I give the first weather book to the guards, and they are quite proud to be given the responsibility. They will take turns, and probably be more than one in the beginning, at least until it becomes routine. They will save the data on a slate board during the day and every evening it will be filled in the book. The maids have done a good job with the temperature data, but from now the guards will collect all the weather data. It will be a part of making rounds, checking doors, the steam boiler and so on, and they'll write the data on a small slate board and hang up alongside the other one. I'll be joining them the first few times so it will be done right. The first pages of the weather book will be kept blank so I can sketch and describe how the measurement values have been collected.

Hopefully I'll be able to establish more weather stations with the same instruments in other places, and all my other mansions will have it, and someone that collect the data.

I'm frankly surprised at how pure the copper is. There is surprisingly little slag. My friends loves how copper have magically grown in my purification baths, and admittedly, it is kind of magical. Somehow, copper travels from one side to the other. How can metal grow? I've used too high voltage and current on these because my goal is to get pure copper instead of big copper crystals, but since I did mention it, I've been 'poked' to make copper crystals. So a special copper bath is constructed with a 12V battery rewired to 2V, and it will be checked every day, but I expect decent sized copper crystals to take a month. Or more.

When she have the time, Bodil will make a couple of special boxes with one and two 12V batteries that will have a big rotating switch in the lid so the cells can be switched to choose the output voltage; 2V, 4V, 6V or 12V. Since all the battery cells are rewired but connected to the load, they are equally discharged, and the current can increase accordingly. It also makes charging the battery pack easier. Not that the cells have exactly the same capacity or performance. The same switch solution can also be used for a spot welder, if the contact blades are good enough. Spot welding is useful.

The workshop have gotten really hot as we reached copper melting temperatures in my small forge, but from the first copper baths, I melt two thick copper plates which after a lot of hammering and annealing becomes approximately 2mm thick copper sheets, and I have help to file and grind them smooth. Something like a diode radio is easy because I only need to find a small point that works, but for an efficient high-current rectifier, I need large areas for less resistance and more current handling, and many, because the reverse voltage is very low compared to what I am used to and need. I'm not sure who bad it will be, but I think it's under 10 volts on a copper oxide diode. I will find out when I measure the diodes to classify them and test that they are indeed diodes. With the design I chose, I will drill holes in the center of all the copper plated before adding the oxide layer, and with an insulated screw I'll clamp several together and build a stack of diodes to achieve much higher reverse voltage. Unfortunately that means much higher loss in the forward direction as well, but such is life here. I am after all making semiconductors in a freaking medieval world, so anything that works it a great success.

In a way, I'll just modify the way I made the copper as I will primarily try electrolysis of the copper cathode in copper sulphate with a little sulphuric acid - ie 'blue vitriol' with a few percent 'oil of vitriol' - as I suspect it is the most accurate and consistent method than heating in a fire.

During the time we've been working on copper, we've also done the final touches on the exercise bike. It is not a pretty creation but it works and have an adjustable resistance. Unfortunately, the resistance adjustment doesn't reach as high resistance as I would like, or compared to other bikes Jane has tried, but it is enough to be useful resistance. The simple distance meter for the exercise bike is more useful, but just a gear reduction connected to a odometer / counter that's located below the handle bars on the frame, and it will reach 99.9 kilometers before looping around, and can be easily reset. There is a 'tempo meter' which is based on the same principle as an old mechanical speedometer in cars, but it is not calibrated. A watch and the odometer along with someone keeping a certain pace will solve that, but I'll run into similar calibrations issued in the future, so I'm thinking of making a rotational speed measuring instrument using to the same principle that I can 'calibrate' and use for similar situations in the future. Anyway, tempo gives an indication of which distance will be reached in a certain time. Jane complain that there is no heart rate monitor, and although I probably could make something that trigger a 'speedometer', it is just a waste of components, and I have my smartwatch for my own use. Admittedly, the added arm trainers is kind of silly and unnecessary, but it is just a couple of simple handles bars with ropes and weights, and was very easy to make.

There is some hesitation in my company to the whole gym concept, and even more so the exercise bike, but with Jane showing the way, it quickly becomes a competition. Mostly between the guards to test who is the fastest to 'cycle' a certain distance with maximum resistance, where Jane keeps the time on her mobile phone in countdown mode. I fetch and hang up a larger slate board, and write 'High score' on it, which makes Jane laugh and shake her head. Jane who has been jogging more than anyone - especially up hills I avoided because of the guards - crushes everyone in cycling, and she don't even try to hide her satisfaction on toping the high score for cycling. Since only one can use the exercise bike and each session takes time, pull-ups becomes another competition.

I suspect that Hillevi will practise and exercise hard until she beats Jane, because Hillevi is competitive and a bad loser and this is something that only requires practise, practise and more practise, and Hillevi regrets that she often let Bodil come along when I jog. After Hillevi literally collapsed so that she needs help, I set a limit to a maximum of two shorter sessions per day up to a 10km distance, or a thirty minute session and limit the maximum resistance with a stop screw. I make them take it easy on the pull-ups and the weights too.

Hopefully three hourglasses will return with the ship, and one can be used for timekeeping instead of clocks. Hourglasses allow anyone to keep track of the time, and it's more visual with the sand flowing out than a digital clock counting down. Eventually, there will probably be a special clock using timing signals in here.