Zeiss Rotating Stage - Need Help

Here you can discuss all microscopy-related accessories and equipment (microtomes, filters...)
Post Reply
Message
Author
User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Zeiss Rotating Stage - Need Help

#1 Post by KurtM » Fri Aug 14, 2020 4:44 pm

Greetings all: I just obtained another Zeiss rotating stage to replace the one I stole from my WL stand to graft onto my Olympus BHS BH-2. I didn't get an exact replacement, however; the 'new' one came from a 'Photomic', I am told. The problem is I cannot figure out how to get this one free to rotate. I'm (more or less) familiar with this stage's operation, and know to tighten or loosen the clutch thumbscrew (7 o' clock in the bottom view below) to enable or disable rotation. But when the screw is loosened, it's like some sort of locking pin is still engaged, that allows rotation only tiny bit either way. I can feel that the stage wants to rotate freely by 'wobbling' it when the clutch is loosened, and it positively locks firmly, with no movement at all, as it properly should when the thumbscrew is tightened.

What locking mechanism can I not find???

PS: I know the stubby thingies at 4 and 8 o' clock (in the bottom view below) are the centration adjusters; any hints as to where I might find the tools for them? (I expect I'll have to make some - my other stage has thumbscrews here.)

PPS: And the thumbscrew at 3:30, just below the Y translation knob, what's it supposed to do? I can't find any use for it...

Thanks!
Attachments
IMG_1911_lzn.jpg
IMG_1911_lzn.jpg (224.84 KiB) Viewed 2854 times
IMG_1914_lzn.jpg
IMG_1914_lzn.jpg (250.92 KiB) Viewed 2854 times
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#2 Post by 75RR » Fri Aug 14, 2020 6:01 pm

I think it best to open it to see what might be jamming it.

One possibility is that the screws that hold the side plates on may be loose.

To open, push the top against the sprung pin, it works just like the condenser attachment.

The little screw next to the Y axis is to control the wobble on the Y axis, it should press lightly on the stage.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

PeteM
Posts: 1510
Joined: Tue Dec 06, 2016 6:22 am
Location: N. California

Re: Zeiss Rotating Stage - Need Help

#3 Post by PeteM » Fri Aug 14, 2020 6:23 pm

Kurt, One guess is that the spring detent (12 o'clock in the second photo) has stuck grease and isn't releasing. Might try some solvent, then grabbing the end of the pin with long nose pliers or something?

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#4 Post by 75RR » Fri Aug 14, 2020 6:28 pm

PS: I know the stubby thingies at 4 and 8 o' clock (in the bottom view below) are the centration adjusters; any hints as to where I might find the tools for them? (I expect I'll have to make some - my other stage has thumbscrews here.)
They can be replaced with thumbscrews - thread is the same. You can move them with thumb and forefinger if you clean and grease them - nice thing is that they are out of the way, so one does not accidentally turn them instead of the condenser centering screws as I am apt to do on occasion.

These are the potential culprits, there are 4 on each side.
.
Attachments
Rotary-stage-bottom.jpg
Rotary-stage-bottom.jpg (36.06 KiB) Viewed 2835 times
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#5 Post by 75RR » Fri Aug 14, 2020 8:33 pm

This is a what does what diagram for those wondering ... what does what!
.
Attachments
Rotary stage.jpg
Rotary stage.jpg (64.43 KiB) Viewed 2816 times
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Re: Zeiss Rotating Stage - Need Help

#6 Post by KurtM » Fri Aug 14, 2020 8:49 pm

No, that's not it. In the picture below, I have removed the stage proper from its quick-release fixture -- which I should have done in the first place, my apologies, I've forgotten how all this stuff works.

So ... There are now what appears to be three rings; the outer two are actually one assembly, and this part remains fixed relative to the quick-release fixture and rest of the stand, has the red arrow pointing to it. The inner ring, with the blue arrow pointing to it, is fixed relative to the stage, rotates along with the stage, inside that outer ring assembly. It's the motion between these rings that is blocked. The amount of freedom, or "wobble", is maybe 1.5 mm. Hope that made sense.
Attachments
IMG_1915_pn.jpg
IMG_1915_pn.jpg (135.57 KiB) Viewed 2812 times
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#7 Post by 75RR » Fri Aug 14, 2020 9:04 pm

If the screws holding the side plates are not loose, and are therefore innocent, then check the brake.

Remove it completely to make sure it is not binding.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

Charles
Posts: 1373
Joined: Mon Mar 02, 2015 11:55 pm

Re: Zeiss Rotating Stage - Need Help

#8 Post by Charles » Fri Aug 14, 2020 9:21 pm

I would also remove the brake and sprays some solvent...WD40 between the white and brass and start working it.

User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Re: Zeiss Rotating Stage - Need Help

#9 Post by KurtM » Fri Aug 14, 2020 9:56 pm

I have removed the brake, it isn't the problem. Dry lube is definitely not the problem -- this stage has been taken apart, cleaned, and re-lubed recently and there's ample evidence of it everywhere. The interface between the white and brass rings doesn't need any more oil, it already has too much if anything. The stage actually is able to rotate ... just a tiny bit. There's something in there blocking the rotation. You can feel it as something hard and definite like a piece of metal, not indistinct and boggy like petrified lube.

I need to learn how to disassemble this thing, I guess...?
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#10 Post by 75RR » Sat Aug 15, 2020 4:25 am

How far have you disassembled it?
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Re: Zeiss Rotating Stage - Need Help

#11 Post by KurtM » Sat Aug 15, 2020 6:06 pm

Okay, I have disassembled to the point where the basic rotating part casting has nothing attached to it anymore, except the two rings. One ring, the innermost one, is fixed to this casting; the outer ring is the one which wants to rotate, but it being prevented from doing so by some obstruction.

Removing the rings is where I'm stuck. How the heck does it come off?? (Talking about the inner ring, as it's the one attached to the stage casting.)

When talking of the basic problem that started all this, please note that I say the ring 'wants to turn', as opposed to saying it 'doesn't want to turn', as is so often the case with antiquated stiff dry lube. Indeed, this stage has been recently disassembled for cleaning and re-lube, and whoever did the work made the error of using too much fresh lube when putting it back together. Way too much, actually. At any rate, the outer ring wants to turn, and actually can a little bit, and it's obvious from that tiny bit that stiff lube is NOT the case here. Some mechanical obstruction is, like a loose part inside.

But how to get these rings off is now the mystery. I have inspected all parts from all angles using excellent light, powerful magnifying lenses, and a stereo scope equipped with a vertical illuminator that allows peering down holes and getting clear views inside. I came to a tentative conclusion that all fasteners had been removed and the inner ring was only sitting on locating pins so I tried prying it up, and tried it in increments around the inside circumference, as opposed to trying to make it move from just one place. It won't budge.

So what's fastening the inner ring to the stage casting?

Picture 1: Bottom view. The outer ring wants to rotate; the inner ring is firmly attached to the stage casting. Speaking to the inner ring, there were three very small screws in the holes marked with arrows or chevrons, and these were removed. (Indeed, I have removed every last screw I can find!) The two holes marked with stars are mysterious; they're not threaded, and they're quite empty with nothing inside them.

Picture 2: Top view. The brass colored parts are actually of the casting, and not separate pieces attached to it, so it's impossible for anything to be 'under' them.

Picture 3: Top view detail. Here we see what appears to be 5 rings visible in the 'window', and I shall number them 1 thru 5 starting with the outermost, at right. So, rings 1 & 3 are the rotating ring. Rings 2 and 4, the black ones, are actually part of the stage casting, and act as 'rails' or guides for the rotating ring to ride on. Ring 5 is the larger, innermost ring that's fastened to the stage casting in some mysterious way.
Attachments
IMG_1951_lzn.jpg
IMG_1951_lzn.jpg (353.22 KiB) Viewed 2742 times
IMG_1952_lzn.jpg
IMG_1952_lzn.jpg (310.11 KiB) Viewed 2742 times
IMG_1957_lzn.jpg
IMG_1957_lzn.jpg (297.89 KiB) Viewed 2742 times
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#12 Post by 75RR » Sat Aug 15, 2020 7:00 pm

The 'fixed' ring screws in and out. There are ball bearings in there!

Assuming the ball bearings are all in the correct place then screw the 'fixed' ring back in. If you go to far it jams.

When you think you have it rotating smoothly then put the 3 screws back in, they will hold it at that height.
Last edited by 75RR on Sat Aug 15, 2020 7:24 pm, edited 1 time in total.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Re: Zeiss Rotating Stage - Need Help

#13 Post by KurtM » Sat Aug 15, 2020 7:21 pm

Oh really ... it just threads out? Like a big screw? As in, "rightsy tightsy, lefty loosey"?

What do I need to know in order to prevent a ball bearing stampede? :shock:
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#14 Post by 75RR » Sat Aug 15, 2020 7:27 pm

Oh really ... it just threads out? Like a big screw? As in, "rightsy tightsy, lefty loosey"?
Yup!

If the stage is flat and and you lift the 'fixed' ring vertically then they should stay in place.

Put a towel underneath just in case.

I am just glad I managed to put mine back together! Still learnt something new ;)
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Re: Zeiss Rotating Stage - Need Help

#15 Post by KurtM » Sat Aug 15, 2020 7:47 pm

That explains why the two holes opposite each other. Now, how to kludge up a spanner to turn that ring?

Whoops never mind I got it.
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

User avatar
75RR
Posts: 7619
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Zeiss Rotating Stage - Need Help

#16 Post by 75RR » Sat Aug 15, 2020 7:52 pm

I pressed down on it with my hand and turned.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Re: Zeiss Rotating Stage - Need Help

#17 Post by KurtM » Sat Aug 15, 2020 11:14 pm

That would never have worked for me here, it kept jamming and actually took quite a bit of effort to get it going again. A couple times I wondered if I'd ever get it apart, it was that bad. I made a spanner out of a pair picks and a small hand screw type clamp, which was a bit clumsy but certainly did the trick and actually worked quite well.

Once I finally got the thing apart I concluded that somebody had recently decided to try overhauling this stage, and made two significant errors: the first was using way too much lube when reassembling, and secondly, went about reassembling the ball bearings the wrong way. This I know because I repeated the mistake, and ended up with the same problem all over again! And again, I had a heck of a time unscrewing the ring because of the balls jamming. Once I had it back apart, I sat and studied it until I figured out precisely how it worked, which then made clear how it had to go back together. Taking this approach, everything went back together perfectly, and it was obvious I had it right.

Interestingly, it felt a tiny bit rough at first, so I found a way to spin it fairly rapidly without stopping, and "ran it in" for five or ten seconds. Now it's buttery smooth. The X and Y motions are very good and need no attention. This is turning out to be a very nice stage.

So a big THANK YOU to 75RR!! The hint that the ring unscrews was the key I needed to unlock this baby! And thank you, Charles, for the hint some years back about Nye lubricants.

Picture 1: My spur-of-the-moment spanner wrench.

Picture 2: The WL is back in business - this is one microscope that seriously just ain't right with a square stage.
Attachments
IMG_1959_lzn.jpg
IMG_1959_lzn.jpg (156.81 KiB) Viewed 2684 times
IMG_1970_lzn.jpg
IMG_1970_lzn.jpg (133.72 KiB) Viewed 2684 times
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

PeteM
Posts: 1510
Joined: Tue Dec 06, 2016 6:22 am
Location: N. California

Re: Zeiss Rotating Stage - Need Help

#18 Post by PeteM » Sun Aug 16, 2020 12:39 am

That's a seriously good and capable looking scope, Kurt.

Hobbyst46
Posts: 3200
Joined: Mon Aug 21, 2017 9:02 pm

Re: Zeiss Rotating Stage - Need Help

#19 Post by Hobbyst46 » Sun Aug 16, 2020 7:21 am

Kurt,
Great salvation job, and team-work !

Naive Question: I thought that the Nye are damping greases. is that important for a rotating stage ? or for any stage ?
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

User avatar
KurtM
Posts: 1632
Joined: Tue Jun 09, 2015 12:08 am
Location: League City, Texas
Contact:

Re: Zeiss Rotating Stage - Need Help

#20 Post by KurtM » Sun Aug 16, 2020 4:30 pm

PeteM, thanks ... for me it's one microscope that's as much fun to look at, as look through.

Hobbyst46, great question, thanks. I thought it might be an improvement in the 'feel' of the stage, as the original one (now on the Olympus) has an exceedingly 'free and easy' feel, as though it is lubed with a light machine oil. Now that I have a rotating stage on either end of the spectrum, as it were, neither stands out as better or worse; it's just two different feels. Your mileage may vary, of course, but both are fine to me.
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

Post Reply