How do I do the math on this one??
 

I need to make 20 squares made from two triangles. The finished square is to be 1 5/8 inches by 1 5/8 inches. I would like to make it the fast way using two squares that are sewn together and then cut apart. My problem is trying to figure out what size the squares that I cut apart should be. Most charts don't go that small . I hear you just muiltiply by .64 but how do you do that with a number like 1 5/8?? Can any math whiz help me??

So sorry; I am not the math whiz you are looking for! Good luck, however.

http://www.patchwork-and-quilting.co...triangles.html
http://www.karencombs.com/formulas_for_quilters.htm
I'm assuming you need half square triangles

Thanks! Looks like I make 2.5 inch squares!

It's probably not the correct way, but I when I cut the squares I just add 1" to the size I want it to end up ( 1 5/8 plus 1 = 2 5/8 ), then trim the HST back down. I hate fractions, can't you tell?

Right there with you! Not sure if it's my cutting or stitching that's always off, but this way I get near perfect HST's. Takes a bit longer but much better results.

Good idea. Give myself a little insurance. This is for a 12 Days of Christmas Wall hanging, so the squares would be very visable.

Here are charts to help you, I love the bottom one to make 8 hst's at once!

Yep. For 1/2 square triangles, add 5/8 to your finished measurement and cut that size. Multiplying by a number (like .64) will NOT work correctly.

1 5/8 + 7/8 = 1 12/8 = 2 4/8 = 2 1/2

I found out that I love cutting down triangles. I took an online class and she had us do that and it was so nice and ever since then, I make my HST a little bigger than suppose to be and cut them down. Love it!