Cytological Preparation

[1dmitri1]

I use toolmaker's vise parallel to 0.0002”, still have too much of the sideways movement while pressing fairly hard, which is not good for the prep, consisting of chromosomes in about 0.1mm layer of liquid between two round glass coverslips 24mm diameter 0.17 mm thick. The goal is to press the liquid out and flatten the chromosomes without lateral tilts to ideally 0.3 microns. I am thinking of any ways to equalize the pressure over the surface of the glass while pressing. Could it be a strong magnet? Maybe a hydraulic gasket between the movable jaw of the vise and the prep could work? Are there small hydraulic cylinders with a “floating” end to even the pressure? Would you, please, help with suggestions and ideas?

Thank you,

Dmitri

 

[GregLocock]

Any idea what force you are trying to generate? I'd think a floating solution would make things worse, to be honest.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[griffengm]

Dmitri,
Can vacuum be used to create an atmosphere more condusive to fixing the cover plate? I envision placing the slide in a vac chamber.

Griffy

 

[Fabrico]

How about 3 micron stops adjacent to the work?

Another way is to pre-load the jaws to one side so deflection does not occur. This would require pre-load greater than the deflection force. It mght also require occasional resurfacing to maintain trueness.

 

[MikeHalloran]

Get a Kurt "Anglok" vise.

Bring your wallet.



Mike Halloran
Pembroke Pines, FL, USA

 

[1dmitri1]

Thank you all very much for advice. The pressure is about half a ton per square inch. Would a vac chamber accomplish this?

Dmitri

 

[unclesyd]

If you have big, big pockets.

http://www.elseworks.com/arnoldclassic.htm

 

[diamondjim]

I think a very large screw would
work much like the old printing
press technology.

 

[GregLocock]

How can a vac chamber generate more than (-) 15 psi?

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[griffengm]

A vac chamber can be as simple as a bell jar, base, some hose and a vac pump. Workers in fiberglass use a large plastic bag for a chamber(google "vacuum bagging").For the size work you describe, we are talking about a fairly small system.
When you draw a vacuum, physical constraints may change and allow you to make the slide. Too deep a vacuum might damage your specimen so the cautious approach is best.
Your problem is similar to that encountered by inspectors when trying to stack gage blocks for truly accurate work. They simply cannot push the blocks together and get the dimension they get by "wringing" or twisting the blocks to remove the film trapped between blocks.
Gotta run. Good luck!

Griffy