I was just wanting the math formula for radius, archways, ect or the easiest way to figure the arc in a archway could someone help me, if so send your information to [email protected] thank you to everyone.
AD
I was just wanting the math formula for radius, archways, ect or the easiest way to figure the arc in a archway could someone help me, if so send your information to [email protected] thank you to everyone.
AD
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Replies
I think if you were to ask Joe Fusco you would have way more info than you can comprende. With some amazing drawing to demonstrate 5 or 6 ways of doing it. You can reach Mr. Fusco here ---------> http://www.josephfusco.com/
Joe H
AD,
One Formula to find the Radius of an Arch.
EX:
Width = 72"
Height = 11"
[W÷2] [x²] [÷ H] [+H] [÷2] = Radius
72 ÷ 2 = 36 x² = 1296 ÷ 11 = 117.8182 + 11 = 128.8182 ÷ 2 = 64.4091 or 64-7/16 - Radius
2nd Formula:
Width = 72"
Height = 11"
[½ W x²] [+] [H x²] [÷] [2xH] = Radius
36x² = 1296 + 11x² = 121 + 1296 = 1417 ÷ 22 = 64.4090 or 64-7/16 - Radius
Using a Construction Master Pro Trig Plus III.
Enter 72 [Inch] [Run]
Enter 11 [Inch] [Rise]
Press [Conv] [Diag] Returns - 64-7/16 - Radius
Hope this helps.
Joe Carola.
AD,
I have two more Formulas to find the Radius of an Arch.
Width = 72"
Height = 11"
First one:
[Wx² + 4xHx²] ÷ [8xH]
72x² = 5184
4x [11x²=121] = 484 + 5184 = 5668 ÷ [8x11=88] 5668÷88 = 64.4090 or 64 - 7/16
Radius.
Second one:
Width = 72"
Height = 11"
[Wx² ÷ 8xH] + [H ÷ 2]
72x² = 5184 ÷ [8x11 = 88] = 58.90909 + [11÷2 = 5.5] = 64.4090 or 64- 7/16 Radius.
Joe Carola.