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The perils of SuperLube

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#1 orlyandico

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Posted 08 September 2012 - 01:18 PM

I don't know if this post should be here or in the ATM or DIY.

Last year I got a 15+ year old AP600E QMD mount. And while it had low periodic error, I always had problems with declination guiding. I tried all sorts of fixes - backlash compensation in the QMD controller, using extended DEC guide pulses using a (trial) MaximDL - and nothing worked.

It seemed that the DEC axis was much less sensitive than the RA axis. I thought the QMD controller's DEC driver - or the DEC motor - might be busted, so I got the Littlefoot Elegance Photo (also to get GoTo). Same thing - now I have GoTo, but declination guiding is still iffy. Seems that at very low speeds the declination stiction was just too great.

A key clue is that the declination axis was very viscous. This was diagnosed as "normal" but I still found it strange. I disassembled the DEC axis and relubed with SuperLube. No change.

The AP maintenance manual (which also advocates whacking the worm blocks with a hammer) specified Lubriplate 105 as lubricant, but because I didn't have that (and had SuperLube, which is widely recommended here) I used what I had.

Guess what. SuperLube is really bad for this mount. I relubed with.. canola oil (still no Lubriplate) and the DEC axis now rotates quite freely. Still not as free as my CGEM - the AP doesn't have any ball bearings in sight - but much more freely than before.

As it's cloudy I cannot assess if there is improvement in DEC guiding. But I expect something...

Moral of the story: SuperLube isn't always appropriate. :tonofbricks:

#2 Dan M

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Posted 08 September 2012 - 02:28 PM

Not saying SuperLube is not useful but I use JetLube MP-50 which was recommended to me many years ago by Larry Myers (owner\operator of Mountain Instruments). It has worked very well on all of my mounts (MI-250, GM100, GM200, CI700) since that recommendation. I barely have to use any of it at all to get the job done. All of my mounts are still going great, years after cleaning\re-greasing them.

#3 simpleisbetter

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Posted 08 September 2012 - 07:04 PM

I'd agree. Haven't tried SuperLube yet as I can't find it locally, but every grease has it's purpose and use, and where it shouldn't. No one product does the job on everything...well...unless we're talking about duct tape, epoxy, & hammers... ;)

#4 TxStars

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Posted 08 September 2012 - 07:15 PM

SuperLube does work good with bearings but is not intended for areas where metal is sliding aginst metal.
Lubriplate is designed for engine & tranny rebuilding where you will have metal sliding aginst metal till the oil begins to flow.
http://www.lubriplat...bly-grease.html

#5 orlyandico

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Posted 08 September 2012 - 10:00 PM

Hm. That explains the popularity of SuperLube. The China mounts all use a pile of bearings. The AP600 has no bearings, it's all metal on metal sliding. The SuperLube actually created this sort of "suction force" which increased friction on the sliding parts.

Good to know. I should find something better than canola oil though!

#6 orlyandico

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Posted 09 September 2012 - 07:43 AM

3-in-1 white lithium grease works just about as well as canola oil. I'm getting really fast at disassembling the DEC assembly...

#7 simpleisbetter

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Posted 09 September 2012 - 07:56 AM

Yes, but the downside to white lithium as I've found out on a mount project before is the oil in it tends to separate and leak over time, especially in high heat. But in cold climates I find it a good choice for worm gears.

#8 orlyandico

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Posted 09 September 2012 - 08:15 AM

Yikes. High heat, check. But it can't be worse than canola oil :tonofbricks:

#9 John Jarosz

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Posted 09 September 2012 - 08:24 AM

Yes it can. The lithium particles that remain after it separates is a solid mass that will prevent the roller bearings from turning. Stiction goes way up. A synthetic is much better. You only need the thinnest of coatings as this is a slow moving application.

#10 EFT

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Posted 10 September 2012 - 09:54 AM

SuperLube must be used very sparingly. It adheres to the surface quite well and requires only a very thin coating. As with most greases, in equipment like this, more is not better. You can lube and entire mount with a 1/2 ounce tube of SuperLube.

#11 orlyandico

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Posted 10 September 2012 - 11:45 AM

hi Ed,

I did use very minimal superlube. But it caused a "suction" type effect and increased the stiction on the DEC sleeve bearing. White lithium works much better.

And I can now reverse directions in declination while guiding - and it works!

#12 EFT

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Posted 10 September 2012 - 02:29 PM

hi Ed,

I did use very minimal superlube. But it caused a "suction" type effect and increased the stiction on the DEC sleeve bearing. White lithium works much better.

And I can now reverse directions in declination while guiding - and it works!


If the fit of two components is very tight, then the SuperLube all purpose grease will be too thick for that application. There is an aerosol version that would probably work better in that case.

Every time I have worked on a mount that has had white lithium applied, it has been a mess. The stuff separates and the light components run out of the mount or evaporate and the remainder ends up like clay. I hate the stuff in this application. It would probably be OK if it were cleaned out and relubed on a regular basis though.

#13 blueman

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Posted 10 September 2012 - 02:44 PM

I like Slick 50 grease, it works nicely for everything from gearboxes to worms.
Blueman






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