Here’s a Rhino command you have never used: fixedlengthcrvedit. When bending physical splines, the length is fixed as the material bends (because the wood does not stretch). However, when modifying curves in Rhino, such as pulling points, the curve stretches. BUT, you can edit a curve and keep its length fixed by using the command “fixedlengthcrvedit”. Very handy to create digital version of the bent wood splines in the previous post.
For example, say you started with a 7′-9″ straight length, and then wanted to move it up 10″ at the mid-point bisector, then use fixlengthcrvedit from the mid point, and move it up 10″ and one end point will remain fixed while the other end point will move in.