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Despite our best efforts–or perhaps because of them if we’re improv piecing!–our quilts are not always square. This happened to me recently as I was working on a quilt from scratch. I was not paying attention and miscalculated a few blocks, so there were some dangling bits and pieces off various edges.
Cut it off!
Thankfully, I had decided to make it a little bit bigger than the standard twin size, so I could just trim it down. This is where one of my favorite tools comes in so handy: the Bosch GTL2 Laser Square. When this baby is on, it shines two lasers at a perfect 90 degree angle that extends far beyond even the largest quilt top! Let me explain how I use them.
First, I gather all my supplies
- One 90 degree laser level (you can work around this if you only have a single-line laser, which I’ll discuss at the end of the post)
- At least one large square gridded ruler (I like the 16 1/2″ one by Creative Grids). I use this for each corner.
- As big a rotary cutting mat as you have. Or multiple mats taped together.
- A second 90 degree laser level
- Blue masking tape (2″ or wider is better, and you’ll see why in a minute)
- More gridded rulers. I like to use all my longest rulers. All of them.
Look it over
When I lay out my quilt, I look it over to see if if it has internal structure, such as blocks that need to be at right angles with the trimmed edge. First, I use my large square to check and make sure the edges of my blocks are perpendicular to the edges I will be trimming. Then I set up my laser level against the square, which gives me my first square corner.
Next is the tricky part! I take my second laser level and set it up on the opposite corner from where I was just working. The hard part is, I am not so concerned about this new corner, but about the corners where there are NO laser levels! Since I know the other laser has been set “perfectly”, I will lay out my rulers using those two lines to get one good edge.
This the finicky bit! I have to finagle that second level around, forward and backward, twisting it back and forth, until I can get a 90 degree angle AT THE CORNER WITH THE RULERS. This is what you’re aiming for:
I’ve got all four corners, now what?
I used to just start trimming, but any nudge on the quilt will throw your lines off. Now I use my blue painter’s tape and carefully line up the edge of the tape with the edge of the laser. I find it easiest to start on a corner with a ruler and work back to the laser levels
I get as close to the laser level as I can without moving it. I also extend my taped line past where the trimmed edges on the opposite side will be.
Trim along the inside of your tape.
What if I only have a single-line laser level?
You can still do this, the order is just a bit different.
First, use your square ruler to find the first corner. Use your single laser to sight down the entire length of the quilt and make sure the corner the two lines you’ve sighted are where you want them. Next, set up the laser level on one of those edges and lay your masking tape down. Then do it with the other side. Now you have those two kitty-corner lines, take your square ruler to the opposite corner from where you started and repeat the process until your quilt is exactly how you want it: squared and trimmed!
I hope this helps you! I love trimming quilts this way because it means I never have to go back and straighten things out. True story, I once trimmed away at one of my first quilts trying to get it square until it was more than 6″ smaller, and some sides were trimmed more than others. Don’t be me!
If you liked this tutorial, you might want to check out my Techniques and Tutorials! Or, sign up for my newsletter on my homepage, where I share these tips and tricks, and interesting tidbits I find throughout the week. Delight in the making, friends!