This model is a setup I am using to precisely control in 1 axis the movement of one chamber relative to a fixed chamber. This setup can go under a confocal microscope and be assembled with very little investment. 

There is a very tiny chance that you would need my model as it is. The most likely is for you to be inspired by this model to create your own. I designed this setup following some critical criteria I had:

• I needed a custom slide holder for confocal microscope
• I have a setup that requires a fixed chamber where I have my sample of interest and a moving chamber that has to be watertight
• The fixed chamber has to be large enough to accommodate a growing seedling
• The moving chamber should be very stable and only move in 1 axis. 
• I am using some capillary devices that have to ho from the moving chamber into the fixed chamber. The tiny holes at the bottom of the chamber are for that purpose. Because of surface tension, I do not see any leaks from these holes. 

Let's say these are the main points.

In addition to 3d printing the parts, you will need two 4mm smooth rods of approximately 65mm, two M3 screws, two ~5mm push springs, a coverslip, some silicon AND the crucial part: a micrometric screw. For this last part, I had a cheap Z stage bought from Optics Focus that I disassembled to take it.

As shown on the picture, the rods go through the main body > spring > moving chamber and lodge themselves in the main body again. By assembling both rods this way, you will have a moving chamber that can only move in one direction.

The locking parts are to keep the rods in place once installed. But they can also be removed in case you break or want to replace something from the setup.

Finally, due to space issues, I had to raise the micrometric screw level so that it would not bump in the stage.

Seal the coverslip in place and Voilà.

Again, highly unlikely that you will use the design as it is but it could give you ideas for your model!