Zeiss Universal-gone

[wstenberg]

I have a project Zeiss Universal stand. Needs a few more parts to be functional. A good start on a new build, or a good source for parts for your current microscope.
I am finishing graduate school, and I am can't move all my microscope projects with me.

I have a few of these Universals in similar condition. Special deal if you want all three of them.

US$120 plus shipping.

[Wes]

How would you center the optovar on this stand?

[wstenberg]

How would you center the optovar on this stand?

There are three little centering screws on the bottom of the head. They often each have a retaining screw covering them. Just adjust slowly and carefully.

[viktor j nilsson]

I recently adjusted these on a Zeiss Fluoro condenser from this era. I didn't think that I used very much force, but I still managed to split both of the two retaining screws when I tried to unscrew them. So be aware that these are quite brittle. Might be wise to heat or lubricate them a bit first. They aren't really necessary, though, but I guess that you might be a bit more likely to lose alignment over time if they are missing.

[Wes]

How would you center the optovar on this stand?

There are three little centering screws on the bottom of the head. They often each have a retaining screw covering them. Just adjust slowly and carefully.

Are you talking about centering of the binocular head port? Because the missing optovar is held to the lower base of the tubehead by 4 grub screws each at 90˚ to the next one. To remove the optovar (not present on this stand) one would unscrew two adjacent grub screws to preserve the lateral orientation but before that put a mark both on the optovar and tubehead to later realign them by making the half marks on each element meet in straight line.

So my question is how would I know where exactly (rotation wise) to fix an optovar unit if I were to get one from a different source. Normally these are factory aligned and you could do something about it by registering the original orientation but I'm not sure how to do it here (because that information cannot be derived).

[wstenberg]

OK, I thought there were three, but you are right, there are four grub screws.

If you have no marks to go by, you can still line it up, but it's a longer process. I've been able to take them off, and change them between microscopes.

That being said, it can take a little trial and error to get it just right.

[Wes]

OK, I thought there were three, but you are right, there are four grub screws.

If you have no marks to go by, you can still line it up, but it's a longer process. I've been able to take them off, and change them between microscopes.

That being said, it can take a little trial and error to get it just right.

But what would you use as a readout of correct rotational alignment? You can adjust the parallel grub screws in tandem to get a good lateral centering while looking down the scope but how would you know when the angle between the optovar and tubehead is correct? For transmitted light applications its not a huge problem but I'd imagine for epi-illumination it might be. What was your strategy when exchanging the optovar units between stands?

[wstenberg]

Start the alignment at the epi-illuminator lamp. Then go to the epi-condenser. At that point, you will have the epi-illuminator tube coming off of the objective holder; just align it by eye to start with-so that the light is going down through the objective.

At this point, make a small reference mark with a marker, to locate your rotational position.
Go back and check your x-y position- checking alignment through the objective.
Then go back and fine tune the rotational position.

A couple of times back and forth will get it into alignment. There may be a more elegant way- but this will work.

Do you have one that you are trying to align?