Dale's Interferometer is great but it had 3 different screw sizes (imperial). I standardized on one size: M3 (metric 3mm) threads which I have tons of and are at my local home depot. Also I added a paper holder. The paper holder still uses Dale's #8 screw but works with M3 as well. I also made the shaft that supports the ball and socket mirror holder thicker and stronger.

I sell the metal parts for this or have information where you can get them and optical parts on your own. Also I have assembly and usage videos for this and the xyz table. All here:
http://gr5.org/bath/

Supports: No

Filament_material:
Print everything in PLA or nGen except nylon for 3 parts (see below)

Notes:
None of the parts need support. I strongly recommend nylon for the mirror_socket and for the lens holder and the cube holder. These need to stretch around something and snap into place. I broke a few pla parts until I switched to nylon for these. All the other parts I printed in PLA but any plastic will do.

The lens holder might appear initially like it needs support but it doesn't - nothing is steeper than 45 degree overhang.

I can be contacted for my suppliers of hardware. Some of the information (like what lens size to get) is here: http://gr5.org/bath/

I'm willing to sell any needed parts (I have a webstore) or give you links to where I buy everything if you would need to make the same product and/or sell it yourself (I'd be happy to shut down my store if someone else made these as cheaply).