Tip - half square triangles
 

I have a huge number of HSTs to do. I usually make them a bit larger and use my June Tailor rulers to line up the diagonal and trim them down to size (I press the seams to one side). I now put a double layer of tape (it's a medical tape that keeps rulers from slipping, but I don't remember what it's called--but any tape could do here), and it enables me to slide the HST right into the tape so that it lines up with the diagonal seam allowance really easily. Then I use the ruler to trim--I find that the tape makes the whole process go faster and more accurately.

Gosh that's pretty clever and should work on any ruler that has the 45 I think I will do this!

Looks like you've made your own version of a Bloc Loc ruler. They have a groove instead of the tape bump, but the effect is the same. There's a physical barrier that you can snug against the seam for quick perfect squaring. Great idea!

I use that medical tape too. Someone at one of my quilt clubs suggested it and it works great.

Thank you I will give this a try.

Great tip, thanks!

What a wonderful idea. You are a smarty and that helps us all! Thanks for sharing this great tip.:D
peace

I don't see the process...can you take a pic with the hst there so I can see exactly how you trim...thanks. When I trim hst I usually open , iron, then square up with square ruler, or I will sometimes use EB triangle square up template on the hst before pressing open.....

I also do not understand the picture. I understand the tape showing you where the triangle is, but I don't see how you trim because the ruler is square. I simply use a square ruler with a 45 degree marking that goes along the seam line. I use a ruler that is appropriate for the square that I am making. Pretty simple and less expensive than rulers that have specific use.

Here's the ruler with 2 blocks. You don't need the June Tailor ruler for this, as someone else said. The idea is to use the tape to lock in the block on the diagonal. It makes the whole process faster and more accurate for me. I place the block under the left diagonal line, lock it in place with the tape, and I trim the 2 vertical edges. Then I rotate the block 90 deg, place it under the right diagonal line, lock it in place with the tape, and trim the other 2 sides that are now vertical.
Any ruler with 45 deg markings will do, but I do love the June Tailor ruler for this.
Hope that clears it up for you.