Sorry for the late note Gambo- we had a problem yesterday and I spent the day working on a circuit board--turned out to be "user error" of course!

Yes-I guess the word "rapid" is in the servo motor or the beholder. At any rate I agree that I can now get a lot of work done quickly for prototyping which is the most of what I do (I work in research where almost every instrument that we build is a "1-off"). I also have a Sainsmart desktop milling/routing machine and I can make prototype -fluidic cells in polycarbonate that would cost $500 and take a month delivery. So I am impressed with what can be done (as I learn) and it saves me a lot of work.

Regarding our mirroring operations-we us a local firm here in the US: https://muellercorp.com/
I definitely see lines in the results that we get so I am guessing better mirroring could be done. (Also better sanding). I have not been doing the sanding so I want to look more into this. But if it is problematic I would look at other mirror options with a thicker build as you mention.

One big problem is that we only sell a dozen of our units/ year and with volumes like that it is not reasonable for even small companies to make things for us.

In this particular lab I am working mainly on the optics, electronics, and spectroscopy for a "Plankton Microscope". The system has a "darkfield" imaging ring at one end--this consists of 2 mirrored plastic rings surrounding a ring of several LEDs--these present a parabolic profile and focus the light into the required ring at the microscope. I cannot afford ray-trace software for this so I am re-designing the work of another using a slide-rule and some photometers in our lab to do actual measurements. I am also considering forgoing the mirrors and using some newer "direct LED" illumination but this will require a lot of tests on the optic-bench. Making small parts for the latter is where the 3D printers shine. I can make dovetailed glides, holders, lens mounts and a whole bunch of things that are not easily available.
So-I will see how things progress but if we stay with mirrors I would certainly be interested in what you do. Sounds like you do interesting work.

My logo is the Viola Clef (Alto Clef). You are the 2nd person in 10 years to realize this! I hardly qualify as a musician (I am a scientist) but I always had a great deal of love for classical music. I play violin, viola and harpsichord. (I built a few harpsichords). When I am not in the lab I like to drink beer and play string quartets--the more I drink the better I sound! My wife is a violinist and we founded a small orchestra here in Falmouth MA, USA. About once a year we get and inquiry about playing with us--from Falmouth UK!

Cheers and many thanks!
Fritz