So, I want to make HST that are 2.5" done and then 2" when stitched in the quilt.

Can someone please help me with the math? I should have listened to my algebra teacher - I guess I really WILL need to know that stuff one day!

Thanks.

If I were making those I would cut my 2 squares at 3 1/4 inches and sew on both sides of a line drawn down the middle from one corner to the other... Then clip apart between the lines of stitching.. Open and press and trim to your 2 1/2"... Exact measurements this way for sure.

Probably the best way. But you and I both know there is a way to figure it out Thankfully, this is for a scrap quilt, so I have PLENTY!

Katie, if you want to do the figuring in the future..

Take the size you want the finished HST square to be. That would be 2" in your example. To that add 7/8" to get the size square needed to make two triangles. So if you like to cut exactly and sew an accurate quarter inch seam you would cut a 2 7/8" square and cut it in half on the diagonal. Or just cut a 2 7/8" strip and make alternating 45 degree and 90 degree cuts. Personally I do as Quiltaholic suggested and cut them a bit bigger, then trim to the exact size after sewing and pressing.

I agree with everyone who has already commented. The only thing I do differently is that I cut my squares 1" larger than I want them to finish (rather than 1 1/4" like Quiltaholic said) and make my stitching line a little closer than 1/4" to the drawn line. Then I trim to the exact size. I don't know why I do it this way but it works for me.

Check out this way to make that HST. I saw this on the Missouri Star Quilt Company tutorials but this blogger has already figured out the math for the finished squares. These are so much easier than drawing that line & sewing on each side & then cutting diagonally.

A 4 1/4" beginning square(s) will give you a perfect 2 1/2" unfinshed square by doing it this way.

http://whipup.net/2011/03/17/g...lf-square-triangles/

This message has been edited. Last edited by: nlk,

Genius! Someone will always find an easy way to do things.

Thank you so much for your help. I knew that someone here would know the math.

I've used that easy way of making those HST's before & it's sooo much better than the "draw a line...sew on each side of line...cut betweeen the sewn lines techique. I don' know how this method was ever figured out but I'm sure glad it was! (I'm not a math person & need all the help I can get in that field)

I like to make things easy on myself.
For HSTs, if its a 2" finished (when sewn in the block) size, then I add an inch, so 3" squares. Square them up to 2 1/2".

Its much easier to square-up if you don't happen to sew a perfectly measured seam.

When making QSTs, I add 1 1/2" to the finished size of the block. The numbers are just easier to remember.

nlk.....I don't use that method you showed for a very good reason.
The straight-of-the-grain of your fabric is at the sewn seam. That means the outside edges of your blocks can skew out of shape when you sew them to another piece.
You have to be ultra careful not to stretch those edges when pressing or sewing.

I was thinking the same thing quiltbea and if it can be stretched out of shape... then mine will and I will be going arrgghhh and throwing a hissy fit. lol

I'm a Thangles girl. I buy the 2" package, pin the sheet to the fabric, sew on the sewing line, cut on the cutting line, trim off any excess, and voila! (btw, it's important to sew on the sewing line BEFORE cutting on the cutting line. AMHIK. )

There was a mini-tutorial a while back...had to hunt it up for you to see.
http://boards.hgtv.com/eve/for...333950957#8333950957

It'd be fantastic for you if you want to make lots of HST...scroll down for the entire thread- mcpatches posted a chart.

And here is yet another HST method like the one McPatches demo'ed

http://podunkpretties.blogspot.../8-hst-tutorial.html

This message has been edited. Last edited by: TcMay,

TCMay.....Now that's a good way to make 8 HSTs at one time. All outside eddges are straight-of-the-grain and won't stretch.
All you have to do is double the size fabrics according to your unfinished needs.
2" finished blocks=3" sqs times 2 = 6" pairs needed
3" finished blocks=4" sqs times 2 = 8" pairs needed
4" finished blocks=5" sqs times 2 =10" pairs needed
and so forth.
They can be squared-up to meet the size requirements.

The math is easy for whatever size you need. I'm going to try this the next time I need 8 HSTs.