When my boss asked me to put together some simple block instructions for Quilting 101 (our free tutorials section on YCQT!), I thought it was going to be easy! I decided to do a simple but fun block called the Double Windmill which is comprised of half-square and quarter-square triangles that are reasonably easy to cut and assemble. I love this block because you can make a whole quilt from just this block, and based upon how you place them, you can get some really wonderful patterns.
I got out my fabrics and cut half- and quarter-square triangles and started sewing. My first block came out wonky–and not in a good way. The second one I cut out was off even before I began sewing. The third was hopelessly out of square.
Not being a complete novice, I started looking at the details. Why were my blocks coming out so very wrong? I went back over the advice I’d written to other quilters:
- Make sure you are using a perfect 1/4″ seam allowance. Test it.
- Keep the fabric edges aligned and sew slowly, checking carefully as you go.
- When using cut triangles, be sure to press carefully to avoid distorting the bias edge.
The thing was, I had done all these things. So, I went to research the block I was making and study the techniques I was using. It was interesting to me that I found none of my problems to be any one of the obvious reasons above. So, I thought I might share with you what I learned so you can avoid making the same mistakes that I did. Here’s what I came up with:
I’ve been changing rotary blades very consistently with each new cutting project, but it didn’t seem to help the fact that the blade was skipping and cutting a slightly wavy edge. After inspecting the 5-year old cutter, I realized that a washer that spaced the blade from the nut had cracked and was not holding the blade stable. I decided a new handle was in order and, as I love to buy new quilty things, I went off to the store and bought a new one which only had three parts to it and no washer. Problem solved, right? No.
The rotary blade was still skipping spots on the cut line. When I looked carefully, I could see that I had solved part of the problem by stabilizing the blade, but I realized that part of the problem wasn’t the blade at all–it was my mat. My mat is in pretty good shape and looks only slightly worn. However, when I carefully ran my fingers across the surface, I found that the mat had an uneven texture to it that could most definitely create a problem for a rotary cutter. The fact is, one corner of my mat was constantly getting used and worked upon, and it had deteriorated enough that it was not working well. I turned the mat so it would face the opposite direction, and suddenly my blade worked perfectly.
I re-cut the block and tried again. It was still off enough that it was too small on one side and too big on the other. Ugh!
I looked next at my pressing. As I mentioned above, I press carefully and don’t slide or stretch the fabric. However, I noticed on one of the blocks that was off that I had created the slightest crease along the seam line of the block. That wrinkle was enough to pull the block out of square. I needed to check my pressing to make sure the seams were lying perfectly flat.
In some of the reading I did, I also found that many quilters actually don’t sew a pefect 1/4″. They sew a scant 1/4″ to allow for the thread or two that the width of the seam takes up. So, I adjusted my process to take a thread less than 1/4″ while sewing. Much better, but still not perfect.
Mystified, I decided to mark my rulers and templates with colored tape to ensure I was actually cutting the proper dimensions of the blocks. I re-checked the plastic templates I had made with gridded template plastic to ensure they were the right size. And, guess what I found?
First, the grid on the template plastic measured slightly less than the 1/4″ it was meant to be. Now, over one or two squares, this isn’t a big deal, but with each additional square, it compounded until it was between 1/16″ and 1/8″ off. That’s a big deal when you’re talking about half- and quarter-square triangles. I hadn’t measured that carefully because I assumed the quarter-inch mark was accurate.
Then, I wondered–what if it’s not the template plastic, but my ruler? I started measuring each of my rulers against others and against the cutting mat I was using. I also measured the tape I use when dressmaking (the one I’ve had since Jr. High Home Ec.) Horror of horrors, many were just plain off, and my beloved (and stretched out) tape went directly into the trash can.
I’m not completely certain how I’m going to determine which of my rulers is correct and which are not. I’ll have to ask my Engineer husband what he thinks, and I’ll probably end up using one of his metal drafting rulers to be the benchmark. I’ll be more careful to use one ruler, or two that exactly match, in the future.
With the Double Windmill, I will most likely cut the block slightly larger than I actually need it and square it up to the proper dimension afterwards. I always thought that if you measure, press, and sew accurately, you couldn’t go wrong but it’s clear to me now that some things can be done better by using simpler methods. I’ll certainly be checking any rulers I purchase from now on, and I won’t be so tempted to buy the least expensive.
I’ll let you know what Engineer Dale has to say when we do part two of this article next week: How to Square Up. If anyone has other suggestions–please do post–I would love to hear them! I’ll have the Double Windmill block out on the site in the next few days for all of you!
Sew Now, Quilt Now!