Macybaby

I'm currently working on a quilt that has about 100 of them - what I've found, you must make sure your starting square is the correct size - right now I'm doing 48 that are 2.5" (finish at 2") and the start block is 1 7/8".

For your triangles, cut a square and then cut diagonal so that your finished edges are not on the bias.

Press so you have the center marked (I finger press) and sew apposing sides, making sure you have point of the triangle at the center - press and repeat for the other two sides.

When you go to trim, find teh center on your ruler and line up the inner block. Since mine will be 2.5", I find the 1.25" line and put it so that it lines up with the corners of the INNER block. Then adjust it up/down and sideways so that you get 1/4" allowance past those corners. I've found if the inner block is slightly larger or smaller (like less than 1/8") I can adjust the ruler so that I've got the 1/4" seam allowance, and it's still OK. More than that and I have problems.

When you square it up, ignore where the points of the outer triangles are - concentrate on keeping the inner block centered. If you lined up your points, there should be enough fabric for easy trimming. If there is not, then cut your squares for the triangle a bit larger.

My number one problems I had at the start was not being extra careful to get perfectly straight seams, and then my inner square would end up not being quite square. I had to slow down and pay attention, especially at the ends of the seam, as that is where I'm most likely to let things slip a bit.

Also, when you press, be careful you don't stretch the ends. I find trimming the dog ears off the first set of triangles BEFORE I press helps a lot in keeping them from getting stretched in the pressing process.