Twister ruler
 

Does anyone know if they make a 3 1/2 twister ruler that could be used on four inch blocks?

google for twister ruler and sites should give you the number of sizes available. Otherwise there have been some posts here on how to make your own.

You can easily make your own, home stores will cut plexiglass for you and then you can mark it with a sharpie. I have done that in several sizes and other shapes that I wanted !!

If your question is: you have 4" blocks to use up and want to make a twister quilt, will the 3 1/2" twister ruler work? You may be short as the ruler is for 5" blocks. You could copy the ruler at a reduction of 80%, use the paper template to make an acrylic, plexiglas, or thick plastic (think flexible plastic kitchen cutting boards) template. Copy the lines onto the template from the paper copy. You now have a twister ruler for your 4" blocks.

check out Twist 'n Stitch by June Tailor at Joann it has 3.5" 5" 6.5" 8" all in one

I made a two inch twister ruler to use with four inch blocks also made a one inch one but haven't used it yet going to use it with two inch blocks

I think the ruler is to be 1-1/2 in. smaller than the block size, have made some the size that I want.

I have the 3 1/2 inch twister ruler and you really need 5" blocks when making it. Four inch blocks would be too small to fit the ruler.