You will get bias edges but I didn't have any problem. Made sure I pressed carefully so I didn't stretch the edges and the fit together great. I haven't had a chance to try them on anything but pinwheeels so far and that was a really small size for a cornerstone.
Cathy

I have been teaching a method of making 4 half square triangles at once for a long time. My formula is to measure the long side of triangle pattern piece. For example if the long side of your pattern piece measures 5 and 3/8 you would cut your two squares 5 3/8". Once you sew all the way around (1/4" seams) and cut on both diagonals you will wind up with half square triangles which will measure 3 3/4. Hope this is clear, if not let me know and I will try another approach.
Renda

GO TO THIS LINK.... IT IS AWESOME!!! YOU WILL FIND THE TECHNIQUE THERE.. :) http://www.youtube.com/user/Missouri.../5/ekYpJzHoW6E

would you have pictures to go along with the instruction sheet?

go to the link I posted above... Missouri quilt one... They have a tutorial on it... :)

this was the neatest thing to see on Missouri Star Quilt( tutorial
on pinwheels).

I know.... I am so happy I saw this somewhere else on this site... I am learning a lot from this group.. :)

My method of making half square triangles applies to any block you are making, not just pinwheels. I do not have photos but will be glad to do some in the next few days if anyone is interested. Just think about all those half square triangle blocks in the Bears Paw block. I would not teach this method until they learned to cut all the triangles and sewed them together.
Renda

To avoid bias edges on the hqt cut bias strips the size of the beginning square and then cut squares. After sewing together and cutting the 4 finished half square triangles will have straight grain edges.

HOT DOG!!! You people are SOOOOO SMART!!! Thanks!