Oval shape formula

Jewelry Discussion
1

Hi

Could someone please tell me how to calculate the area of an oval
shape? does someone have a chart for different sizes of different
gauges for sterling for weight estimation?

Thanks in advance.

Rajah

2 
  does someone have a chart for different sizes of different
gauges for sterling for weight estimation?

Hi,

Check out our MetalCalc at : http://www.ganoksin.com/MetalCalc/

MetalCalc helps calculate the length or weight of various
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Hanuman

Dr. E. Aspler
aspler@ganoksin.com
Managing Director
Ganoksin Jewelry Co.,Ltd

Webmaster Ganoksin Online
https://www.ganoksin.com

ICQ # 864 5224

3

Dear Rajah,

try http://www.Dendritics.com/metal-f.htm It calculates the weight

thanks

Ahmed Shareek

4

Oval area =(3.14*(width+length)2)/16

in other words= width plus length squared, multiplied by 3.14,
all divided= by 16.

example: oval 5 by 7

  • =(3.14*(5+7)2)/16
  • =(3.14*(12)2)/16
  • =(3.14*144)/16
  • =452.16/16
  • =28.26

=09
FADY SAWAYA.
@Artemis

5

Could someone please tell me how to calculate the area of an oval
shape?

I’ve always used pi * (average radii) squared.
Say 6mm * 4mm oval.
radii =3mm and 2 mm
(3 + 2) / 2= average radii
area = pi * 2.5 squared
area = 3.14159 * 6.25
area = 19.63mm
Am I doin’ something wrong?

Bruce D. Holmgrain
@Bruce_Holmgrain
http://205.177.16.22
703-593-4652

6 
  Could someone please tell me how to calculate the area of an
oval shape?

The area of an oval (ellipsoid) is: A= pi (ab) where A= area,
p1 = = 3.1416, a = 1/2 of the long dimension, b = 1/2 the
short dimension. Example: = area of 10x8 oval, A = 3.1416 x 5 x
4= 62.832.

 does someone have a chart for different sizes of different
gauges for sterling for weight estimation?<<

See the ‘Weight Charts’ in Tim McCreight’s ‘The Complete
Metalsmith’. The= re are lots of other valuable formulae & ideas
in this book. IMHO, anyone in the jewelry industry should be
required to own & USE it.

Dave

7

Could someone please tell me how to calculate the area of an oval
shape? does someone have a chart for different sizes of different
gauges for sterling for weight estimation?

Forgot about the silver weight estimation. By multiplying the
previous area by the thickness, you will have the volume in mm.
There are 1000 cubic mm to a cc and one cc of sterling weighs 10.36
grams( the specific gravity). So for a thickness of say, 2mm:1

19.63mm * 2mm = 39.26 cubic mm
39.26 cubic mm  = .03926 cc
mass = 10.36 * .03926
mass =  .4068

I hope that’s right. Sometimes I blow it though.

Bruce D. Holmgrain
@Bruce_Holmgrain
http://205.177.16.22
703-593-4652

8

I have not seen the formula given for an oval. It is as follows:
A=3.14 xdD where d is the long diameter and D is the short diameter
of the oval. This will give you the surface area. Look in the metal
calulations for that much area for a given gauge thichness and you
can determine the total weight.