This profile gauge, also known as a contour gauge, lets you copy any 2D contour for transferring or for measuring. It has a sliding lock (shown in the last two photos) that lets you lock the profile in place. It will handle profiles up to 24mm deep. The short version with 40 slats will handle contours up to 64mm, the longer version up to 96mm. Or you can scale the whole thing up to copy any size you like.

Printing
This is designed for 0.2mm layer height, and I would recommend using PLA. It is important that the slats all have a completely uniform thickness. For some reason, Prusa Slicer was giving me a little extra material on the tiny areas of solid infill, causing the ends of the slats to be a tiny bit thicker. To eliminate this, I printed with 5 perimeter lines and zero solid top and bottom infill layers. All the other parts print with normal settings.

You'll need to print 40 slats for the short version or 60 slats for the long version. Also print one of the cage parts (long or short), one clamp and two each of the end slats, both regular and the fat versions.

Assembly
Insert one of the thin (not fat) end slats (the black parts in the photos) in the cage. Then stack up your 40 (or 60) regular slats. Finish with one more of the thin end slats. You'll notice that the little hooks at the open end of the cage are tapered, and match the taper of the little sliding clamp piece. Slide the clamp, narrow end first, into the gap left between the last end slat and the hooks. There is a tiny lip at then leading edge of the clamp that will snap under the far edge of the hooks as you slide it in. With the clamp in the “released” position (shown in the 3rd photo), the slats should all slide easily but with a little friction. Sliding the clamp to the “locked” position (shown in the last photo) should make it very difficult to slide the slats.

If the fit in the locked position is too loose, replace one of the end slats with a fat end slat. If still too loose, use fat end slats on both ends. On the other hand, if the slats are too tight in the released position, remove one of the regular length slats altogether, and then use thin or fat end slats as needed to get the right fit.