Dating curta calculators
The Thacher's box was cracked and pretty beat up but intact, and the K&E label was still there,albeit torn and loose at 3 corners and hanging on only the upper right corner pin. I've tried having them done on a variety of large format laser printers, including those used by the big office stores, and none are accurate enough for slide rule purposes.
The width of print varies vertically by as much as 1.5 mm in 12 inches, and the width of the A scales never matches that of the B/C.
In spite of the poly coating, some water gets in and warps the paper intolerably.
It's also important to avoid any sort of cement that sets up quickly.
I kept the front face of bar 16, the only one that came off intact. It's glued directly to the steel bar, and near as I can tell the bars are in no way sealed from rust.
The paper came off easily with a razor blade and then I sanded the bare metal.
If you would like me to rescale your original Thacher's ruined, unusable scales, please contact me at [email protected] keeps the work flat, prevents it from shifting, and lets me lift up the work and sight along it from many angles to make sure everything is coated.I've found that at least 2 coats are needed per side for adequate results.Second, there's finding a glue that won't stretch/warp the paper at all, and that won't set up too fast or slow.And third there's getting each scale into the right position and holding it there while the glue cures.