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quilting math help

My friend mis-cut her fabric for a quilt. She asked me on the phone how to use what she has to make it work - but, naturally smaller.

The quilt called for strips to be cut 3" wide and 2" wide.

She cut all her strips 2" wide.

She's thinking if she made the blocks smaller and used the 2" strips in place of the 3" strips she could then cut down her remaining 2" strips to the smaller size.

The question is what that smaller size would be.

Here's what I was thinking.....remove the seam allowances and you have

2.5" and 1.5". The smaller strip is 2/3 the size of the larger.

So....taking the strips she has cut at 2" and removing the seam allowance and multiplying by 2/3 I get ....ugh. Something close to

29/32. Would it be ok do you think to just say 7/8 plus the 1/2 seam allowance and have her cut the second strips at 1 3/8 (which is a less miserable measurement to cut than dealing with 32nds and not too much smaller)? Or, since it's a simple strip pieced thing just go for easy and cut the second strip at 1 1/2"?

The local shop owner "made up" the pattern but it's really a square from the larger strip framed (or sashed) on two sides by the narrower strip. Put four of those together (two with the sashing to the center and two with the sashing to the outside) and play with the design.

marcella

Reply to
Marcella Peek
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Without seams the 2.5" and 1.5" strips are proportionally

5/5 and 3/5 - not 2/3. So your friends smaller strips would have to be cut to 3/5 of 1.5" plus seams. That's about 0.9" plus seams = 1.4"

Sounds like as long as they are a consistent size it will work in her pattern so - try a couple of blocks with 1.5" strips.

Reply to
CATS

OK, now I'm lost. When I divide 1.5 by 2.5 I get .6 which is 2/3 in fractions.

marcella

Reply to
Marcella Peek

2/3 is really .66666666 (and so on to infinity)

Your .6 is correct (being 3/5), and 1.5" x .6 is .9", not an easy thing to cut. (Although 7/8 + seam allowance would be pretty close).

But ultimately, it may not matter. If it's strip pieced, and the final unit is a square, the narrow strips can be *any* width, as long as the final unit ends up a square. Let's say she uses 2" cut strips and 1.5" cut strips. Then she can cut the squares at 4" and still be fine. Or if she wants to be super-economical with the fabric, use 2" cut strips and 1" cut strips (cutting 2" strips in half as needed), and cut the squares at 3".

Personally, I'd see cutting the strips too small as an opportunity to go shopping for more fabric. ;-)

Reply to
Kathy Applebaum

.6 is the same as 3/5, but 2/3 is .67 -- closer to .7 than to .7. But it sounds from your description that it doesn't matter if the strips aren't the exact proportions as the original. Either 1-3/8 or 1-1/2 should work.

Julia in MN

Reply to
Julia in MN

And this is why we get along so well :-)

marcella

Reply to
Marcella Peek

Think of it this way. There are five 0.5"units in 2.5", and three in 1.5". So the proportion to scale down from 2.5 to

1.5 is 3 parts of 5.

Sounds like all you really need to do is make the smaller strips 0.5" smaller though.

Reply to
CATS

finished, the smaller is 3/5 of the larger...which isn't going to work out any nicer, given quilters like to work in quarters, but, same logic as you, but different ratio (2/3 would be the unfinished ratio for the original pattern size, but that won't apply to the adjusted size, the seam allowances don't shrink too).

new larger strip finished is 1.5 inches

so new smaller strip finished it 1.5*0.6=0.9

add seam allowances and it's 1.4, which is nearer to a 1.5 inch strip than a

1 and a quarter, but nearer still to a 1 and 3/8 if you fancy cutting that!

Personally, I'd consider making up the block without shrinking the intended smaller strip, the results will be subtley different, but could be pleasing and they can always be cut down, the extra fabric will be wasted either way unfortunately.

Anne

Reply to
Anne Rogers

I didn't do that division, I saw the proportions CATS saw, but as a rule of thumb, if the start and finish are fractions, either work in fractions throughout, or change to decimal at the very beginning and work in decimals throughout, then only back to fractions at the end. Decimals and fractions don't always easily interchange, it's much easier to work with 1/8th then .325 and then if you work with .325 there is a tendancy to drop it to .3 and when you go back to fractions you've suddenly got something difference.

To change a decimal into a fraction, write the numbers after the decimal point on the top, with 1 followed by as many 0s as necessary (the same number as how many you wrote down on the top), so 0.6 would be 6/10 or 3/5 when you simplify. (As an aside, if the one you have on the top is recurring, you use the length of the repeating unit on the top and subtract

1 from the bottom, so 0.666... as a fraction would be 6/9 i.e. 2/3!)

Anne

Reply to
Anne Rogers

Gosh, I'm glad there are some math whizzes here! This whole thing confused the heck out of me; I'm math challenged. I like Kathy A's advice -- the LQS is calling. ;)

Reply to
Sandy

Use the 2" strips as they are. Cut additional fabric to get the 3" strips.

If she likes the design, use the second half of the 2" strips to do it all over again, cutting more fabric for the 3" strips.

Myself, when I do a blooper like that [can you believe it, the first Yellow Brick road quilt I did], I reason that it was because I'm supposed to do another quilt with the "miscut" pieces. Less aggravating, less hair-pulling, and way more fun!

G> My friend mis-cut her fabric for a quilt. She asked me on the phone how

Reply to
Ginger in CA

Howdy!

Amen, Ginger!

And if you don't use the mis-cuts in another quilt, send them as scraps to Roberta Z.

Ragmop/Sandy

Reply to
Sandy Ellison

She won't buy additional fabric. It's just her thing; hence the ask for help with the math.

Everyone makes their own decisions and that one is hers. What are ya going to do? ;-)

marcella

Reply to
Marcella Peek

I'm totally hopeless when it comes to this. If I have to re-do measurements, the only way I can do it is if I draw the block out on graph paper, making the ratio as large as necessary, to see how I'd have to adjust it. Once it's in this "picture" form, I can figure it out from there. I guess I'm too visually oriented, to do the math first, then go from there.

René

Reply to
René

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