Need math help

Kim,

I'm not sure I have quite understood, but here goes:

156 squares: finished 6 inches, so you need to cut them 6.5 inches.

Across a bolt of fabric you should be able to get 6 6.5 inch squares.

156/6 = 26 So you need 26 rows of 6.5 inches.

That is a total of 169 inches, which is 4 yards and 25 inches.

Now, how many 1/2 square triangles do you need?

Hanne in London

THANK YOU! A total of 40 1/2 sq. triangles plus 4 setting triangles.

OK, let's try that:

40 HST (I assume these are for the sides of the quilt, right?)

They should be cut 6 7/8 inches square, then split on the diagonal. Please note that if they are for the sides of the quilt, it will give you bias edges on the outside!

Anyway, you need 40 HST, that is 20 of the 6 7/8 squares. You need 4 strips of 6 7/8 wide, then cut 5 squares from each. That is a total of

27.5 inches.

By "setting triangles" I guess you mean the corners of the top? So 4 QST? Again beware of bias on the outside. For this you need just one square and cut them all from that one.

Now if all your setting squares and triangles are from the same fabric, you should need

169" for squares 28" for HSTs 8" for QSTs

(I've rounded up on the last two).

Total of 205", that just under 5 3/4 yards. You might want to add a little extra for shrinkage etc.

You might also want to wait a few hours and see how many tell us that my maths is bad :-)

Hanne in London

Hanne - thank you! You are correct, all the squares, 1/2 and 1/4 sq. triangles are all the same fabric. And I always overbuy anyhow just for kicks & giggles. I knew 30 yds. was just waaaay too much and probably had I worked it out the way you did for me I could have done it. I was going on the sq. in/yd. of fabric thing and that was just making my head spin! The bias on the outside should be a treat as I'm planning on doing a large scalloped edge treatment! But after my last adventure with 2 triangle borders to make up a zig zag border - the scalloped edge should be a breeze!

Kim in NJ

I also thing the sq inch calculations can cheat you a fair bit: What if the squares (or whatever) that you need to cut _just_ do not fit nicely across the width of the fabric. Then there is a certain amount of waste (not really, this can be used for something else, but in terms of the calculations), and that is hard to keep track of if only doing sq inches.

Me, I always draw a little cutting diagram :-) Like the end of a bolt of fabric, then mark out x pieces across (or at least write it), then work out how many rows. Sometimes a partial row of one size fits with one or more partials of different sizes. This is particularly worth it if I have only just enough to do what I want.

And yes, 30 yards is too much! At least for one normal size quilt it is. I think I've seen rough estimates that for a pieced top to expect about

3 times the sq inches of the finished top to be used in the making. But that is for everything, and you needed only setting squares/triangles. Obviously you managed to befuddle EQ :-)

Glad to help.

Hanne in London

I believe that's always been a problem with EQ. The way it estimates fabric for triangles doesn't work well.

A bit of a reminder of how EQ figures yardage estimates.... The program draws a rectangle around each shape in the quilt. If your squares are on point, they essentially figure a square around that square, which is a lot of waste. To get a more accurate EQ estimate of yardage, do a horizontal layout of the same number of squares you need, color them all the same and get the fabric estimate for that fabric. For your setting triangles, color the side setting tris a different color, the corner tris a third color. Then check the layout they use, by clicking on the tri, then print-rotary cut. If it is a quarter square triangle divide the fabric requirement by 4, if it is a HST then cut the fabric requirement in half. A bit of a work around, but you don't have to do much math. And the requirements are usually on the long side too.

Pati,> AuntK wrote:

How many plain and how many 1/2 sq. triangles? Two colors I'm assuming.......

Assuming half and half and having 44" fabric (not using selveges):

You can get 6 - 7" blocks from each width of fabric (I'm allowing 7" in order to have a little cutting fudge allowance.

6 x 7" = 42 inches

From each yard you can get five widths.

5 x 7" = 35 inches

From each yard, you can get 30 pieces. The allowance

6 blocks x 5 widths = 30

For 156 squares: 156/30 = 5 1/4 yards.

I'd get 2 3/4 yard of each. That way, you'll have a couple of strips left for your next log cabin quilt!

Hope this helps.

Lenore

Kim, maybe EQ5 has your blocks set to a much larger size?

-Irene

AuntK wrote: