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Measuring and die rotation

Started by gbansal, December 07, 2013, 01:49:18 PM

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gbansal

How do you measure legend size , numeral size ?
Did you use caliper to measure this dimensions ?

Globetrotter

Hi,

I have the 3 tools of our trade: a caliper, a scale and a magnet as shown in the attachment. As you can see, I work with a 0.01 precision on both. You can buy both on EBay, the magnet you "steel" from the door of your wife's fridge! On top of that you need a camera with a macro possiblity and a tripod. A free software like "photoscape" and a presentation software like "powerpoint" do the rest....

If you have more questions please feel free to ask them.

Regards

gbansal

nice information !
How do you measure legend size or numeral size using caliper

Globetrotter

Just by applying the caliper as shown here:


Globetrotter

The caliper from Amazon is fine, since it has to metal!

The magnifier is for stamp! You just need a simple magnifier 4 to 8 times manifying power! something like this is good!
http://www.amazon.com/s/ref=nb_sb_sabc?url=search-alias%3Daps&pageMinusResults=1&suo=1386442451906#/ref=nb_sb_ss_i_0_10?url=search-alias%3Daps&field-keywords=magnifying%20glass&sprefix=magnifying%2Caps%2C390&rh=i%3Aaps%2Ck%3Amagnifying%20glass

For the scale look for something like this "electronic scale 0.01", since you don't collect stamps, but coins
http://www.amazon.com/American-Weigh-Signature-AWS-100-Digital/dp/B0012LOQUQ/ref=sr_1_1?ie=UTF8&qid=1386442381&sr=8-1&keywords=electronic+scale+0.01

Maybe other folks have other recommendations?

Take care

gbansal

thanks alot !
How to measure die rotation like we have in CROSS coins .

Globetrotter

That's a good question, up to now I do it with a guesstimation, but I'll try to figure out how to do it exactly, just give me some time....

See you later

Figleaf

Don't use this method on proofs.

Draw a circle of the same size as the coin on a piece of paper. Use a compass, not the coin itself. Mark the exact 12 or 6 o'clock point of both sides on the edge of the coin with a fine drawing pen. Transfer the two points on the coin to the circle on paper and wipe the ink off the edge of the coin. Work quickly and the ink will not have dried and will be easy to remove.

If you are good at math or an excel god, you can calculate the angle of the lines between the centre of the circle and the two points on the circle by measuring the distance between the two point on the circle in a straight line (callipers) and using trigonometry. Otherwise, you can draw the two lines and use a protractor.

If you are really desperate, create a pie chart with two numbers (x and 360-x) in excel, hold the paper in front of the screen, so that the graph shines through and adjust x by trial and error until the lines on paper match those on the chart. Your die rotation is the value of x. The size of the pie chart is not important.

Peter
An unidentified coin is a piece of metal. An identified coin is a piece of history.

Globetrotter

#9
Hi Peter,

I've tried to make it graphic.....

Regards

Figleaf

An unidentified coin is a piece of metal. An identified coin is a piece of history.

Globetrotter

Hi,

I simplified my explanation since there is no need to make 2 points on the coin, ONE is enough!

Take care

gbansal

Simply awesome Globetrotter . thanks alot
Thanks figleaf

You saved mine 30$
I was going to buy rota flip to measure rotation in the coins but was not sure where it will work on Indian Coins or not 

canadacoin

One of the easy and cheap way of measuring coin rotation is to mark 360 degrees rotations on both sides of the regular coin holder such that axis are aligned on both sides. This can be achieved by overlaying protractor and the regualr coin holder. Then simply place your coin into the holder, secure it by applying staples or by pressing holder flaps (if you have self adhesive holder). Degree of rotation wil be seld evident.

dheer

Quote from: canadacoin on December 10, 2013, 03:28:05 AM
One of the easy and cheap way of measuring coin rotation is to mark 360 degrees rotations on both sides of the regular coin holder such that axis are aligned on both sides. This can be achieved by overlaying protractor and the regualr coin holder. Then simply place your coin into the holder, secure it by applying staples or by pressing holder flaps (if you have self adhesive holder). Degree of rotation wil be seld evident.

I fully agree and use this method. It quite easy to use. I am typically not interested in exact degree of rotation, so it helps.
http://coinsofrepublicindia.blogspot.in
A guide on Republic India Coins & Currencies