Hi Guys
Job now done! RA and DEC axes both re-greased with all the old gunk removed. The mount moves so much more freely now, and the slews sound so much less strained. Need to take it out and test GoTo accuracy and tracking accuracy to make sure I haven’t disturbed anything.
In the end, I used
3-IN-ONE Professional White Lithium Grease obtained for $10 from Autobarn, for packing the shafts and bushes, and
Silicon Grease for the Worm.
Here is some more information I found along the way:
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http://tech.groups.yahoo.com/group/ss2k/message/6549
Teflon greases and lubricants shouldn't be used in telescope mounts. Any lubricant containing suspended particulates will harm worm accuracy.
http://physics.beloit.edu/observatory/user/manual.html
"Greases containing suspended particles (e.g., moly or graphite) should never be used in precision bearings or screws, as these particles will seriously interfere with tight tolerances."
White lithium grease is an excellent mount lubricant for all climates and temperatures.
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SS2K Yahoo Groups:
“Vixen uses two types a 100% silicone grease on the worm gear and a synthetic grease on the bearings”.
“I have a Mountain Instruments MI-250 and Larry Meyers recommends white lithium grease for the gears”.
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http://tech.groups.yahoo.com/group/ss2k/message/6559
I am aware that most Teflon particulate lubricants have particulate sizes of about 100 microns on average and most of the particulates are not spherical but more like irregular shaped pancakes that stack up, pack up, break up and redistribute themselves under normal operation. They are also very compressible.
There are some where the particulates are ground to sub-micron size for specialized high-speed, high temperature applications.
In all cases the lubricating film thickness is unpredictable and highly variable in operation. Certainly not conducive to telescope mount accuracy.
Here is the only sub-micron Teflon lubricant I could find on-line:
http://www.worldklass.com/pro_drytef.html
Much better to use a lubricant that is much more compatible with scope mounts like white lithium grease.
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I also read a couple of instances where use of petroleum based greases may contribute to some adverse reactions between stainless steel and aluminium.
I am repeating the above stuff like a parrot, as I have little knowledge in the domain of lubricants and so cannot attest to its accuracy and/or relevance.
The quintessential CG5 mount website:
http://www.astronomyboy.com/cg5/index.html
Cheers
Dennis