Jennifer has given permission to post this link to her tutorial for a clever alternate way to make HSTs. Try it out, and see what you think. The measurements she gives will create a 4" (finished) block. Note that the link posted above is directly to this tutorial; to go to her latest post, click on the title Bronze Wombat at the top of the picture.
For the record, I do not know what a Bronze Wombat is; perhaps we should all ask Jennifer?