A remarkable little item! Do you need to take magnetic declination into account when using it? I could see such a device being a BIG hit with steampunkers (steampunk aficionados?). Excellent small scale workmanship.
Yes. Sundials work on geo-north only. But, in the 16th century, the best clocks at the time were only good to about 15 minutes per day. ;) Out in the field, I use a universal azimuth card because it will also tell me sunrise and sunset. Now, if you combine an azimuth dial and a geo-north dial like his, when they line up, you'll be looking north.
Doesn't this ignore the fact that the geographic and magnetic north are only lined up in a few places on earth? Looks like your 'gnomon' is pointing at magnetic north.
The compass could be rotated to compensate for Variation, often confusingly referred to as declination, (declination is also an astronomical and celestial navigation term of considerable importance) and either adjustable for changing location, or fixed, for one local area. If you look at a navigational chart, next to or within the compass rose the nominal Variation should be given as well as the annual change in Variation, for correction of the given Variation which is correct only for the year of publication of the chart. As it so happens, where I live, the Variation is rather small. 1°25' W, which in this sort of extremely crude and inaccurate sundial can be ignored as insignificant. In some other locations within the continental US, it can be over 16° and therefore would definitely benefit from correction, by simply rotating the compass relative to the device the appropriate amount and direction. Make no mistake, when all relevant adjustments are permitted or implemented, and the device is of reasonable size and accurately constructed, a sundial can easily determine time within a minute or two, and also the date. A pocket sundial is, even if carefully constructed, more of a conversation piece than a timepiece. One could well be forgiven for using magnetic North rather than True North, for orienting this sort of sundial.
You should put up I video of max, and minimum loads, vs barrel length and bullet weight. I'm not the only home builder out there that could learn a ton from you. Is this all just wax slugs?
Hello ian. I made a prototype out of scrap wood fixed to a post in the garden and marked out the hours over a couple of days. I had a rough idea of how the markings should be from images on google. Hope that helps. All the best SF Thank you for the sub. Much appreciated.
@@SwallowForge Thanks very much! Mine's looking nearly as good as yours, but not finished yet. Have bought compass and a tiny 15mm x 5 dia spirit level instead of the plumb bob Pics when finished!
