I feel obligated to show what the fuss was all about:
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Way more work than the outcome justifies but much has been learned in
the process.
BTW this is the only one of my dials that is pure metal.
Now I can move onto other things...
Michael Koblic,
Campbell River, BC
Very nice, and just in time for the winter haze which obscures the sun
up there for six months, eh?
The etched numbers are quite classy and worthy of the time, IMHO.
Got a portable sundial, complete with compass, that people can take
with them? For survivors of 12/21/2012.
--
That's the thing about needs. Sometimes, when you get them met,
you don't need them anymore. -- Michael Patrick King
It can be done. It would have to be some sort of inclining effort in
addition to the compass which ramps up the cost. Some of mine can be
adjusted with a bit of effort. I made only one outright adjustable:
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The problem is that not many people are interested in the high end
stuff.
Michael Koblic,
Campbell River, BC
(Ooh, noo! He said "try and")
Yeah, I can imagine they'd be picked up as an unusual item, more for
their fun value than their function.
The unwashed and I bought our Casio "sundials" at Walmart for $26,
complete with dual time functions, countdown mode, stopwatch mode,
light, 5-year battery, and waterproof to 50M.
--
The problem with borrowing money from China is
that thirty minutes later, you feel broke again.
--Steve Bridges as Obama
Man, some idiot took a wire wheel to that deburring tool/countersink
and took the edges right off it. Maroons!
By the time you got done deciphering the glyphs, you'd know Chinese.
Why convert after that?
--
The problem with borrowing money from China is
that thirty minutes later, you feel broke again.
--Steve Bridges as Obama
That is an interesting one. Presumably Chinese although I cannot rule
out Japanese. They are two equatorial dials I suspect for Southern and
Northern (on the right ) hemisphere - however, the markings seem
different on each.
Knowledge of kanji (about elementary school grade 4 here) is one thing
but being able to read them when they are "handwritten" is another.
Then there is the issue of how time units were defined. For instance
on the Northern hemisphere dial numbers are clearly discernible,
however there are also two other scales: The outermost one I cannot
make head or tail of. The innermost one shows e.g. character for noon
marking a period extending half an hour outside the 12 o'clock. Each
of these periods has an "up" and "down" (or "top" and "bottom")
segment (sounds like baseball?).
Both dials are adjustable for latitude but I do not see numbers on the
respective scales and I wonder if the characters there are name places
corresponding to the correct latitudes (this is often seen on European
dials).
The compass also has several scales - the cardinal points are marked
on the middle scale but what the others do is a mystery to me. Also: I
cannot find a way to correct for declination. I suspect there is one
because: 1) Declination has been known since well before Columbus and
2) The cardinal points are accompanied by a character for "correct" or
"true", so I suspect there is a way of distinguishing them from the
magnetic directions.
It would be fun to see this close up.
Michael Koblic,
Campbell River, BC
Right. Thanks. I forgot about the Greenwich site and that it has the
two versions shown. The markings are a bit different. The other two
web sites are also interesting although some of the description is
word for word taken from Greenwich. Most of my questions remain
unanswered.
1) Why are the bagua trigrams sometimes different (I have seen the
"south" trigram used for "north-west")?
2) Wherefore declination?
3) Why have a North and South hemisphere dial on the same instrument
in a country that is entirely north of Equator (unless one is supposed
to turn the thing 180 degrees and use the other dial for some other
purpose than just simple time-telling)?
4) The nature of the markings on the latitude adjustment - one web
site agrees with my guess that these are place names, the other
suggests these are calendar references somehow related to latitude
(???)
The instrument itself is quite simple and of limited utility as it can
only be used 6 months in a year. However, the cultural connotations
are fascinating and probably more involved than I am prepared to spend
time on. At least for now :-)
Just to prove that I have been to that Greenwich site before here is
one I made which was inspired by D8644:
are the type/style I find interesting or pleasing. Would enjoy studying
them up close, in person. This one would also be fun to peruse for a
bit and might even be affordable:
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I found some info, directions for making one of those here:
formatting link
For some unknown reason I find these little ring-sized pendants nifty
too (and expensive...):
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I'll look in my Antiques book, but I don't remember it having
much to say about the sundial in question. I did find this little
snippet:
"This wooden equatorial sundial, a traditional Chinese form, uses a
copper pin as a gnomon and a brass strut to incline the plate. A
compass provides north / south alignment. Unlike western versions of
this sundial, which list cities at each latitude for the proper
inclination of the plate, Chinese dials refer to the local chhi' or
calendar system used in regions of different latitudes."
from this page:
http://64.107.216.64/research/collections/reflections/index.shtml
If I find anything else of interest I'll let you know.
Pendants "work"?
--
The reasonable man adapts himself to the world; the unreasonable
one persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man.
-- George Bernard Shaw
That type of equatorial dial works all year round. Unusual gnomon - a
strip of light rather than a shadow, I think. There is a similar one
in Vancouver.
Actually that is a huge ring dial working on the same principle as
this:
formatting link
Usually these dials adjust the position of the aperture according to
season to show time. With a stone monolith it would be tricky so the
spot of light falls on the appropriate date of the analemma at midday.
Like you say, a calendar, somewhat over-engineered :-)
I like these a lot. Their main benefit is that they need not be lined
up by compass. If you get the latitude and day of the year right the
spot falls on the hour scale and the dial is automatically in a
correct position. I want to make one of these but it is an engineering
nightmare (for a mutt like myself).
I think it is meant to be a version of the universal ring dial like
the one above but lacks some essential features that would make it
work as such: There is no adjustable pinhole on the gnomon that I can
see.
Word for word from the other web site you linked to.
If you want to study some really cool ones these are it:
The following link (which I posted before) has pdf files that you can
print out and then scissor, glue, make a very similar, if not same
model. I only gave the pdf files a quick glance but that was my
impression. I would go ahead, print out and make the paper one. Then
study the paper model, parts and decide how to best reproduce it in
metal. You could use the paper pieces as a pattern and prick punch the
degree markings through the paper. Then finish the markings with a cold
chisel. The first one may not look so pretty, but it would give you a
warm fuzzy feeling and the next one would be better after you have
stumbled around some... Even thin wood or plastic should work I think.
I've seen your creations and I'm sure you could make one this way.
Yes, those are really nice and way out of my price range. Sure would be
fun to futz around with them for awhile though :)
Probably old news, but have you seen/tried these programs for
calculating sundials?
formatting link
I've been playing around with "ALEMMA" (seems to run on Linux via WINE
okay), seriously thinking about building one out in the yard. Use patio
stones, bricks and such. Would be pretty neat to have out in the yard
for daydreaming and such...
I looked in my book and find my memory was wrong. It wasn't the dual
version in it, just a single side that inclined like we've already
pointed out to each other. No useful info other than the date
and maker.
[...]
Actually the markings are the least of the problems. The three
adjustable rings and a gnomon with an adjustable pin-hole worry me far
more. If I get around to it I might make one that has fixed parts to
start with.
[...]
I use Blateyron's "Shadows" but I only have the free version. I have
not felt the need for the Pro-version so far. Thanks for the link
though, I should see how these programs stack up against the Shadows.
It's one of those things one would like to see close up and have a
Chinese speaker standing by.
Michael Koblic,
Campbell River, BC
Hmm... The rings are stationary, only pinned best I can tell. Look
closely at this one from the wikipedia site:
formatting link
and folded/flat:
formatting link
The inner ring simply swivels inside the outer ring 90 deg (so it can
be stored/carried flat). The hanging part looks like a wire that simply
fits in a groove going around the circumference of the outermost ring.
The degree markings look standard (really 0 to 90, quarter circle). The
gnomon or bar is pinned at the 90 deg mark on the outer ring and
allowed to swivel or spin around to whatever position need be.
So it looks to me like you need two rings that fit together. Outer most
ring needs to be put on the lathe and a groove made around
its circumference to hold a wire for hanging (latitude adjustment).
Drill a small hole through the outer and inner rings opposite each
other. Maybe use a punch (crude but should work) to deform one of the
rings over the pin location to secure said pin. At 90 deg away from
this pin the gnome needs to be secured to the outer most ring. The
image shows rivets were used and opposite sides of the ring so that the
inner most circle can be swiveled flat to store.
I think some careful measurements from the similar pdf model's
gnome-slider area could be used to get the month settings transfered.
Might be able to use the flat image from wikipedia for this also.
Did I miss something else other than to add the markings?
Yes, that would be really cool. I've spent way too much money through
the years buying stuff to fuddle around with due to curiosity and
wanting to learn something...
You still have to have a good fit (particularly if one is to reproduce
the folding option) and more importantly good alignment. The
attachment points of the gnomon alone are difficult enough.
Still, I am looking forward to seeing your version. I hope you post
the pictures. I shall stick to the simple stuff.
Michael Koblic,
Campbell River, BC
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