If one tends to misplace charts - which I do -
A fairly easy way for me to figure out 'how much I need'
Figure out the perimeter of the item - (the length of the four sides) - I add at least 20 inches to allow for corners (on a big quilt to allow for possible shifting of where to splice for corners and joining the ends
multiply by the width of the binding
and divide that by (usable width of fabric x 36)
In your case, this is how I would figure out how much I needed.
perimeter length multiplied by width of binding = square inches of fabric needed
(52 + 52 + 64 + 64 + 20) * 2.25) = square inches of fabric needed
252 * 2.25 = 567 square inches
square inches of fabric needed divided by (how many square inches are in a yard)
567 / (40 * 36) = exact yardage needed
567 / 1440 = .39375
This, of course, does not allow for pattern matching, or any extra for cutting errors.
3/8 = 0.375
1/2 = 0.500
I would buy at least 1/2 yard of fabric for a 2.25 inch binding on a 52 x 64 item
The show off way of entering it in my calculator would be like this:
((2*52 + 2*64 + 20) * 2.25) / (40*36) = .39375
Last edited by bearisgray; 10-08-2012 at 07:44 AM.