New to me Covell 14 Comparator- What have I gotten myself into

[Choiliefan]

I too would be very careful cleaning your mirror and it may be best to remove it before proceeding.
A mild dish soap with gentle rinse and pat dry.
I had a Scherr-Tumico comparator and found the 10X lens the easiest for transposing measurements.
Also came with a set of centers which iirc replaced the XY stage and a useful surface illumination light fixture.

 

[silverforgestudio]

Heres the 10x that was installed in the Unit- I have placed a cap over this workhorse so She doesn't get dinged...


Here is the "steal" of the day- the drawer held a series of lenses- R to L:
20x 31x 50x 62x

There are fractions on the 31 and 62 (1/4 and 1/2 respectively) And I would assume the math for the lenses is magnification based so Im interested in knowing if anyone has the magnification equations (or knows where they can be sourced from)


The BnS Micrometer dial for the XY table- it is in good shape cosmetically and works smoothly throughout its travel.


Here is the major casualty of the move- the XY table fell apart when we tilted the cabinet- nothing major dinged or scratched- but the ball bearings went all directions and the brass gibs went another- so I now have a "fixer-upper" portion to this ol gal.

This is the bottom of the table



Here is the underside of the "Top" of the table with the parts found- the 2 rectangular tabs and the washer are parts to the observation rotating ring. As you can see- Im missing a ball bearing...

 

[gradient]

A very good and old method of cleaning mirrors, especially first surface mirrors is to use collodion.

Collodion Optics Cleaning - How to . . .

Cleaning the optics of our telescopes is something most of us dread ? and with good reason: aside from dropping the OTA on your driveway, nothing has a greater potential for damaging the optical surfaces Cleaning Modern Antireflect...

www.cloudynights.com

I have used this with great success on mirrors and ruled gratings for telescopes and other optical surfaces.

 

[silverforgestudio]

While I don't know, I would suspect that the mirror is a front surface mirror where there reflective coating (Silver?) is laid down on the front surface of the glass. household mirrors it is on the backside and so the glass protects the mirroring surface. A front surface mirror is very easy to damage.

Very true and thus the "cover and wait till I know more" philosophy- Thanks for the tip!

I too would be very careful cleaning your mirror and it may be best to remove it before proceeding.
A mild dish soap with gentle rinse and pat dry.
I had a Scherr-Tumico comparator and found the 10X lens the easiest for transposing measurements.
Also came with a set of centers which iirc replaced the XY stage and a useful surface illumination light fixture.

Thanks Choil- Im afraid to even mild dish soap this one as it has a few schmutz areas I can not tell if it is de-laminating or if it is surface grime... Nice to know the 10x is the "workhorse" lens- I have a feeling I will be starting with it as well!

Thanks for looking and contributing to the knowledge guys!

 

[silverforgestudio]

A very good and old method of cleaning mirrors, especially first surface mirrors is to use collodion.

Collodion Optics Cleaning - How to . . .

Cleaning the optics of our telescopes is something most of us dread ? and with good reason: aside from dropping the OTA on your driveway, nothing has a greater potential for damaging the optical surfaces Cleaning Modern Antireflect...

www.cloudynights.com

I have used this with great success on mirrors and ruled gratings for telescopes and other optical surfaces.

AWESOME and thank you! However this article says the fellow did NOT have good results- I will continue to look at Collodion- and the thought of primary mirror cleaning is now in the hunt as well (off to a telescope forum!)

I truly appreciate the assistance. Thanks folks!

 

[Choiliefan]

It's possible your mirror is polished on both sides.

 

[gradient]

The collodion article was to give you full disclosure As I say, we have had good luck with it on really critical front (first) surface mirrors and gratings. Try it on a small corner of the mirror as a test. The nice thing about it is that you don't have to do any rubbing on the surface. Pour it on, let dry and peel it off. The dirt and munge sticks to the collodion. But as they say, "your mileage may vary". Good luck with a nice instrument.

 

[silverforgestudio]

Understood Gradient- and I hope to be doing some ore research this week as well for this method- I have several "vintage" SLR cameras with silvered mirrors that were stored in an open face container- their mirrors may be a great way to practice- thanks!

 

[C-Bag]

I've seen OC's on CL, some real cheap. And after picking up a stereo microscope for $40 it has made a huge difference in my bit grinding technique. This thread has been very enlightening, thanks.

 

[silverforgestudio]

Update for the folks about town- So the Comparator is functioning and I will be upgrading the lights to LEDs.

The Table mechanism and ball bearings will be "tabled" (pardon the pun) until the lights and mirror are addressed. Thanks to Paul and Rodger (neighbors I didnt know prior to this adventure) for inviting me into their shop for a test drive of their Johnson Comparator.

This item will have more use than originally thought as I am now the proud owner of a large box of watch/clock gearing to "learn" on!

In other news I WILL be painting this ol'girl as I have found she likes her new home by the door and my TOES are suffering! (One day I will learn!- HA!)

@gradient - the Collodion will be the next foray as well. I am thinking this fall as my "shop" area doesnt get to a decent relative humidity and temp sustained until October/November timeframes

Stand by as she gets up and running!