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Square up pieced blocks perfectly. Ideal for use with rotary cutter.



While most acrylic tools are designed to accurately cut fabric pieces, this tool will help you confirm accuracy of work in progress. You will find that the time spent squaring up or perfecting sub-units is worth every minute and this tool will make these tasks easier and faster! You will discover as many ways to use the Is It Square?™ tool as there are patchwork blocks. View a closer look at the Is It Square?™ Tool.

Centering Circles

There are two centering circles in the Is It Square?™ tool - one for 30°, 60°, and 90° angles and one for 22 1/2°, 45°, and 90° angles. Use angled lines to determine if seams are straight and at the proper angle. First lay the tool on top of your block. Then align the tool with the grid lines so that the block is straight and the seams in question pass exactly through the appropriate centering circle.

schematic of Is It Square? tool placement on fabric to check quilt block seam straightness and angle accuracy

Assess seam accuracy as early as possible. For example, if you are making six-pointed stars check the accuracy of the seam angles as you build the stars. This will allow you to correct problems more easily. After all, who wants to rip out set-in work?



Checking Seam Intersections

When you align a piece or block with the center at half the finished block width from the 1/4" seam allowance marking you will see if seam intersections of pieces, blocks, or sub-units (e.g., the points of stars) will be cut off. If the points fall within the 1/4" seam allowance, they will be cut off, and if they fall short they will "float".

schematic of checking seam intersections on quilt block

Checking Blocks and Pieces

To determine if sides of pieces are even, use the grid lines to align the piece. To determine if pieces are square (e.g., half square triangle blocks) center the piece in one of the centering circles and use the grid and grey square outlines (1", 2", 3", or 4") to assess the squareness. The grey square outlines along with the 1/8" grid help you to visualize whether the piece is square. For blocks smaller than 10" finished, align the block center with the center of the tool and use the grid lines to assess the squareness of the sides and the dimensions of the block. Doing this before you combine blocks in your quilt top or even before you combine pieces into the block may save you hard work later. In addition, use this piece/block placement to determine the unfinished size of the block and visualize any required trimming.

schematic of checking squareness of pieces within quilt block


For blocks larger than 10 1/2" unfinished (up to 16 1/2"), align the center of the block with one of the centering circles and use the grid lines to determine if the sides of a quarter of the block are square. The numbers in the clear or filled circles show the distance of the sides from the centering circle (filled circles give distance from the lower right centering circle - when text on the tool is right side up). The centering circle is two inches in from the 1/4" seam markings at the edge of the tool so you may see how seams of the block continue past the center. Assess each corner of the block in this fashion.

schematic of checking squareness of quilt block by measuring distance from the center


Squaring Up

The only way to have one-step checking and cutting would be to have a separate acrylic square for every possible size square that you might piece (and, of course, a closet large enough to store all of the acrylic pieces). In most instances, checking and cutting is a two step process. This tool supports both tasks. To square up a block, you may either trim, using the tool as a guide, or use the tool as a guide for marking, and trim separately.



If the unfinished block is to be 10 1/2" unfinished blocks (10" finished), you can center the block at the center of the tool, align seams, and trim with the tool as a guide.

schematic of checking squareness of quilt block by placing tool on top of quilt block


If the block is smaller than 10 1/2" unfinished, you may use the tool to trim each edge. Align the block with the center the finished block width plus one seam allowance (1/4") from the edge of the tool and trim the side. Do this for each side.

schematic of trimming quilt block using Is It Square Acrylic tool


schematic of marking quilt block for trimming using Is It Square Acrylic toolFor blocks larger than 10 1/2" unfinished, align the block as discussed above and mark the edge of the unfinished block. Slide the tool to continue marking a side, keeping the alignment. Do this for all sides and then use a longer ruler, the Draft n' Cut™ Acrylic Tool to trim.





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