It took two days of fettling with calculations to get the triangles right. Two long, dispiriting days. My own fault: I know I have my own instructions for measuring and cutting triangles, up in the attic somewhere. But I couldn’t be arsed to rummage around for them, so I tried to work it out.
First I used a triangle ruler (pictured right), overlaid over the template I drew, to work out what size to cut my triangles to. At the bottom of the green and white sketch, you can just about make out my original calculations.
I have never found a use for that triangle ruler. Largely because most of my quilts are based on strips, not triangles. And when I do use geometric shapes, I free cut them to make assymetrical, rough and ready finished pieces, like the Granny Quilt, where none of the finished triangles are *quite* the same as each other, or the Eye Spy Starz quilt. I haven’t done a mathematically precise quilt since…. Oh, the Irish Chain, I think! Back in 2003! And that was squares…
Well, I’ve used the triangle ruler now. And probably never will again. I’m not sure what it’s *for*, but accurate cutting and measurement of triangles doesn’t seem to be it. Overlaying that on the template, and cutting to the requisite shape provided entirely the wrong sized, mismatched block (see left). My finished block needs to be 9 1/2″ square. The triangle template gave me a 10 1/2″ square. Trimming that down would have meant losing roughly quarter of my beautiful, sharp points…
After much experimentation, I can confirm that the way to measure right angle triangles is to treat them like half square triangles (which they are) and measure the length of the side either side of the right angle. Then add 7/8″ for seam allowance, which gives you the central, diagonal seam allowance, and your 1/4″ all round standard quilting seam allowance. So on that basis, all the small triangles are 3 1/8″ squares. The big triangles are 5 3/8″ squares. And the uncut squares are 2 3/4″.
Each patterned block (24 of) is made of 22 pieces of fabric. Then there are 12 blocks made of two pieces each. Then 8 plain blocks. Then 72 sashing pieces, 44 hearth squares, and 4 borders. That’s 680 pieces of carefully measured, cut, stitched and fitted together fabric to make one layer of a quilt. Phew! I’ve been making blocks in groups of four, and machining them on a production line basis. This works for me, as it breaks up the measuring and cutting time (which I don’t particularly enjoy) with the sewing time (which I do, as the logistics of the production line approach are quite complex and need me to concentrate, but the rewards are far greater!)
I’ve made the majority of the blocks, now. Here’s a selection of entirely correct ones (four in each colour way). I have 8 more of these to make, and 4 half square triangle blocks. That’s a mere smear 96 pieces of fabric to measure, cut, and reorder. Easy. That should take no more than three hours of tomorrow, then. And then I simply have to cut my hearth squares, and put the top together. So there *should* be a photo of the completed quilt top by the end of the week, all other things being equal!
I’m enjoying my accuracy on this project (she says, taking a huge red flag and waving it defiantly in the face of the bull of fate…). So far, my triangles all have points, which float correctly (there’s one in the top left corner of the left-most blue block pictured which is *slightly* blunted, but that’s the only one). My pinwheel points match correctly. The bad news for my sister is that, if this persists, I may feel the need to enter the finished article into the Festival of Quilts, this year. It’s not as non-traditional a piece as I might have liked to enter (but I may also put in the Japanese Geek Quilt) but it’s a modern setting of a traditional block… or combination of blocks. I don’t know. Will consult with my friends at Rats as Big as Cats and nbnq to see what they think. But if I do submit it, it will mean poor Sissy has to wait an extra month or two for her wedding present. Still, I’m on track to deliver it within the first 10 years, so I can’t see she has *much* to complain about!!