I have these perfect laser-cut acrylic templates to make this Rose Dream quilt block (for a 6" block). Now I need to create illustrated instructions to make the block from fabric. Been doing this for years, so the instructions are not the issue. I created the block quickly in CD, no problem. However, when I checked it against the acrylic template, the arcs of the lens-shaped piece did not match. Took me awhile to understand that the creator made the template a specific width, so it's not a 90° arc.
So...the challenge is to create the block so that with of the arc is 2.00" (that would make the height of the arc 1.00"). If you're bored or curious to try, I've attached a PDF with a few more details. BTW, I think I found a way to do it, but I'm curious to see if someone comes up with another way. Just keep in mind...all the geometry I know, I've learned as a quilter. My hubby told be this is really trigonometry. RoseDream_challenge.pdf
Hello Patti,
Does what you need have to be a circular arc? Here's one way to do it that uses a 3-point curve.
I have a macro that can "offset" a straight line by a specified distance. I used that to create a duplicate of the diagonal line that is offset by 1" from the original.
Then, I drew a 3-point curve, using object snaps to snap it to:
Sometimes the answer is right there in front of you and you still miss it -- totally forgot about using the 3-point arc! What I did was similar, in a roundabout way. I added a center node to the 90° arc, created a 1" line from the diagonal center and then dragged the center to the end node.
Thanks for that link to PlanetCalc! Now about creating it from the circular ellipse with a 2.75" radius...not sure how you did that and made it fit the on the diagonal 4.2426 line. Can you enlighten me?
pranderson said:Thanks for that link to PlanetCalc! Now about creating it from the circular ellipse with a 2.75" radius...not sure how you did that and made it fit the on the diagonal 4.2426 line. Can you enlighten me?
I started with a circular ellipse, and a horizontal line offset by one inch from the top:
Using the Shape tool, I dragged the node of the ellipse to only have it span a fraction of the full 360°, and to be open instead of a pie wedge:
I finished by trimming off the ends using the Virtual Segment Delete tool:
I would then rotate the curve 45° before placing it.
I wasn't "counting clicks" on this. There may be a slicker way to do that.
OK, thinking on this, one simpler way to do this is to not think about the arc, but instead, about the whole shape.
Intersect the ellipses to get this: