Slit - Variable Width- Optic for Spectrograph

A variable slit for use in a spectrometer or other optical setup.
3d printed parts
Single Edge Razor Blades (2x)
2mm diameter metal rods cut to lengths (tolerance for cut length is very forgiving like+-5 mm):
144 mm (2x)
90 mm (2x)
52 mm (4x)
15 mm (4 X)
M3 bolts 10 mm (4x)
0.4 x 5x 30 Compression Springs (7x)
M5 bolt (1x) at least 50 mm
M5 nut (2x)
Standard Single Edge Razor Blades (2x)
Super Glue (1x)

Assembly:
Glue two 15 mm rods into the divots razor block mounts.
Insert the razors into the notch. The razors can be clamped with m3 bolts but they actually fit snugly so there is not need.
With a spring between them thread the the two 90 mm rods through the holes of each razor block mount such that the razors are facing one another. Set razor block mount assembly aside.

Thread a 50 mm M5 bolt through a nut and inset it through the middle hexagonal hole. Add another nut on the other side and tighten deez nuts until they are holding the bolt pretty tight.

Ins