Optical Centering Microscope

[rwm]

(Not sure where exactly to post new projects now, so move it as you see fit!)

I am contemplating an optical centering microscope (alla Stephen Gotteswinter).

I have started collecting a few parts.





I have not made any drawings yet. Just flying by feel. I have a 10x eyepiece and a 4 x objective.
Interestingly, I was told by people online that this will not work. They insist there is a problem with aligning the optics that does not make any sense to me. Has anyone else actually built one? Did you run into problems?

Robert

 

[JimDawson]

..........I was told by people online that this will not work. They insist there is a problem with aligning the optics that does not make any sense to me.

Looks like a fun project. Is it going to be without some challenges?....No, but that's part of the fun of doing it. I would design in a method of adjusting the mirror after assembly.

Naysayers drive me nuts. People said man would never fly, the 4 minute mile was impossible, if you sailed out in the ocean too far that you would fall off the edge, and many other examples of what can't be done. Those who say that it can't be done should stay out of the way of those doing it.

 

[rwm]

Thanks Jim. I am hoping to have the mirror solidly mounted so a bump will not affect the centering. Assuming I can machine a mount very close to 45 deg, what would further alignment be necessary? The plan was to align the center by moving the mounting shaft with respect to the body of the device. I was going to make a recess with 4 set screw and use that kind of like dialing in a 4 jaw chuck.
I do have an idea for adjusting the mirror if all else fails.
Robert

 

[JimDawson]

It think you have it under control. You may find that the view through the eyepiece may not align exactly with the view from the objective lens without some adjustment. Your plan for adjusting the spindle center with the objective lens sounds correct.

 

[rwm]

Any one know how I can glue a front surface mirror (back is glass) to aluminum? Cyanoacrylate? Red Locite? Is there a glass adhesive?
Robert

 

[f350ca]

Double face tape?

Greg

 

[brino]

rear-view mirror adhesive from an auto-parts store?
though I believe it is just a fancy cyanoacrylate.

But get it right the first time, my Dad tore a chunk out of a new windshield pulling off a mirror anchor that he accidentally put on upside down.....one of those lessons I'd rather learn by seeing....

-brino

 

[JimDawson]

I was going to say rear view mirror adhesive but @brino beat me to it

 

[rwm]

Great ideas boys! Cyano can cause problems with glass due to vapor deposition. The windshield formulation does not have this issue. Just for fun I may experiment with Loctite too.
Robert

 

[RJSakowski]

As I recall, he stuff that they use for rear view mirrors is an acrylic adhesive. There are a number of urethane adhesives that will not give off vapors. Loctite sells them.

You might also look at some of the UV curing adhesives. They are used for optical assemblies. Loctite again but they are also starting to appear on the consumer market as a kit. I used UV laser pointers for curing but you could also use hi intensity blue LED's or just let it cure out in sunlight.

Another possibility would be to make a clamping arrangement. That way, you could replace the mirror easily should the need arise.