How do you change the size of quilt blocks? If you pattern is different than you need it.
Thanks for your help.
Tammy in MI

It depends. If it's made of half square triangles that finish at 4", you start cutting at 4 7/8" (or 5"). So if you want to enlarge so they're 6", cut 6 7/8". Depends on what the pattern/components are. Link/picture?

i'd like to know that also. if the pattern is sisters choice, with all those pieces, and it's a 10" finished block and you want to make it 8" or 12" how can you change all those pieces? i wouldn't even know what size strips to cut, never mind adding 7/8". wouldn't the pieces be some weird measurement, iike 13/14ths or something?. especially if you started with pieces calling for 7/8" and you wanted to enlarge 1/3 or 1/4. or in the above case, going from 10" to 12" you're enlarging 1/5th. (right?)

I don't know if this is what you're looking for

BLOCK SIZE WANTED (divided by) CURRENT BLOCK SIZE = PERCENT TO ENLARGE OR REDUCE
Example:
To enlarge: Size you want = 12" and Current size = 4"
12/4=3 (answer times 100 = 300%)
To reduce: Size you want = 7" and Current size = 12"
7/12=.58 (answer times 100 = 58%)

I from the old school. It it wasn't and easy pattern with just squares and triangles, that you have formula for. I would redraft the pattern to the size I needed and decide how to cut from there.

sometimes the pieces within a block are so weird to start with it doesn't work.
i should just take one look and turn the page.

I think if you used a photo copier to reduce or enlarge the block or blocks to the size you wanted, then made templates or paper pieced, it would work.

that's what I would do too, but I make my own pattern most of the time.

Ok, here is a chart that may help you. You might need to take your pattern to the library or a Kinkos to get it sized to the correct percentage. Pocoellie is on track with her formulas, but here are some sizes already done for you, if math makes your head hurt. lol Print it out for future reference. http://www.thequiltedsnail.com/scale.html

Thank you. What a wonderful site. So useful.