I wanted to quilt circles to complement the linearity of the quilt top and to enhance the illusion of overlapping squares. I did a practice trial of large concentric circles using PowerPoint. The addition of the smaller circles at the block intersections and outer edges is an experiment still to be decided.
The thought of marking all those circles and then trying to stay on the lines while sewing on my domestic Pfaff was overwhelming. Keeping the feed dogs engaged would involve a lot of turning. The limited throat size on the Pfaff would certainly challenge the ability to make the circles smooth with dropped feed dogs and free motion quilting. I considered doing a funky, free-form kind of sketchy approach to the circles, but I really did not want that sort of look. So I set this top aside until a solution within my skill level could occur to me.
Then I got my HQ-16 sit-down machine Heidi in the fall of 2014. I felt my skill level was insufficient to do circles freehand, but Heidi would enable me to sew smooth circles by using rulers and no markings. I just had to get my skill level up for consistent stitch size and comfort level using rulers. I have this ruler set of half circles in 1" increments for diameters 1" to 12". It was a Christmas gift from my son and daughter-in-law shortly after I got Heidi. It was the perfect tool and I was itching to use it for this quilt top.
I did some planning on how best to do the concentric circles. Sewing on the outside of the curve gives even numbered circle diameters and sewing on the inside of the curves give odd numbered circle diameters. The largest circle I could make was 12" diameter, a bit shy of the 16" block but it would need to suffice, so I chose even number diameters. When stitching toward the ruler, it is best to approach the evens from the outside in and the odds from the inside out. I was actually a bit proud of myself for noticing that! Concentric rings with 1" radial spacing (2" deltas on the diameter) seemed just dense enough. I would do 12", 10", 8", 6", 4", and 2"arcs.
I would need to keep switching ruler size, so I kept them handy on a chair I pulled up beside me while I sat at Heidi. Attaching all those sandpaper gripping strips took a while but they are SO necessary to minimize slippage. I was certain to place the rulers sandpaper side up on the seat so as not to sag the seat cushion loose weave fabric. This meant I also had to remain aware to flip the ruler when using it as a guide on the quilt top.
Uniform circles were not a guarantee however, if the ruler slipped ... whoops. I think I may have put the ruler down gripper side up. Hence there was not enough friction and it drifted while I was holding it. The path is still smooth though and not jagged. I backed up and started on the correct path and would pick the errant stitches out later.
Especially for the larger arcs, I really needed quite a few sandpaper grippers. I doubled the number seen in this photo after getting the glitch shown in the upper left. It is hard to hold the 10" and 12" rulers since the size is as large as my hand will span. It is also more difficult to follow an outside curve than an inside curve. It is doable and the registration marks on these rulers are great, but it is a skill than needs practice - and lots of grippers. I also learned it is better to do a quarter-circle at a time even though the ruler allows for a half-circle.
Here is a closeup of that glitch. I recover by just backtracking while I am in the area and leaving the picking out until later.
Along the outer edges I am doing concentric half circles. Because I wanted them a bit smaller I chose to use the arcs labeled 1", 3", 5", and 7" diameters instead of the 2", 4", 6", 8", 10", and 12"arcs from the overlapping squares. I also wanted to try sewing on the inside curve for comparison. What a difference! It was much, much easier to stay on the inside track and doing so allowed me to concentrate more on consistent stitch length.
I am close to the finish line. I have one more side edge of concentric half-circles to do and those two three-quarter small circles near the center. I have not yet decided if they should be the smaller odd diameters like the edges or fewer of the even diameters like in the center. Then there is a bit of picking out. My bobbin just ran out. That is a sign to take a break! I will check out Let's Bee Social #127.