Mount grease

[zicklurky]

I've been using lithium TF2 grease for my HEQ5, but I've started noticing the mount gets a bit stiff when it gets cold. It was -2 and frosty last night and when loosening the clutch on RA it hardly moved when moving RA by hand. Guiding was working, but was much worse than at the start of the night.

Any thoughts on  better grease type? 

[triton1]

I used the Teflon TF2 grease (red in colour) and haven't experienced any problems and that was over 2 years ago 

[Alien 13]

I am a firm believer that the Skywatcher grease is the best stuff out there bar none most of the alternatives are not sticky enough and end up leaving the bearings dry.

Alan

[swag72]

Don't put in car scratch remover ............... Don't ask but I picked up the wrong tube! I wondered why the mount was making a funny noise ..... but on the plus side, the cogs were scratch free    

[PhotoGav]

This is a very interesting thread. I leave my mount out in all weathers, though covered, and have often wondered if I should give it some greasy tlc every now and again! So, where do you buy this Skywatcher grease from - is it a FLO thing? And how do you go about applying it to an HEQ5 pro mount? Thanks in advance and sorry if this is subtle thread hijacking!

[spaceboy]

I used TF2 but found it broke down far too quickly for my liking. I will point out that my mount is in an Observatory which is subject to everything the sun has to throw at it so temperatures can get reasonably high inside during the height of summer.

 

After no end of searching the net I came across recommendation for http://www.amazon.co.uk/Synthetic-Grease-Syncolon-Purpose-Lubricant/dp/B000XBH9HI/ref=sr_1_1?ie=UTF8&qid=1455212488&sr=8-1&keywords=super+lube superlube which so far has been superb. It has a little bit of stick to it so it remains in place but it's nothing like the tar the Chinese slap on these mounts in the factory.

[zicklurky]

I'm using white lithium grease. It's been great when it's not too cold, but the cold seems to stiffen it. I'll have a look at the Teflon TF2, thanks. 

I'm not sure if one can buy the grease Skywatcher uses in their mounts. I had to clean mine off and regrease, most of the grease had gooped to the side of the gears and they were quite bare.

6 hours ago, swag72 said:

Don't put in car scratch remover ............... Don't ask but I picked up the wrong tube! I wondered why the mount was making a funny noise ..... but on the plus side, the cogs were scratch free    

Haha! Whoops!

[Dave In Vermont]

As a bicycle-mechanic, I'll share a tip on grease: You should clean out the bearings and the races they ride in before applying new grease. Especially if you're using a new grease and don't know what was used before. I use charcoal lighter-fluid to clean old grease out. Just do this in a well-ventilated space - like outdoors. And don't smoke near it! And don't be afraid of getting grease on your hands - work the new grease into the bearing, around the bearings, and every surface the bearings will be in contact with. Just be careful you don't use so much that it can migrate elsewhere that you really don't want it. E.G. Optical surfaces.

I use SuperLube, which contains PTFE (Teflon®). It maintains it's properties well below 0-F. I've removed this stuff that had been in the bearings for 20+ years. Still working fine.

Hope this helps.

Dave

[m.tweedy]

here is the proper stuff

http://www.rothervalleyoptics.co.uk/geoptik-equatorial-mount-grease-kit.html

[AtmosFearIC]

I tried to find Superlube in Australia not long enough but couldn't find it. I ended up using Ultralube which is just a multipurpose Lithium Grease. It seems to be working really well so far, I guess only time will tell.

[mirceaar]

Hello

I have an (N)EQ5 Synscan mount that so far has had its original SW sticky grease changed as follows:

Its first owner cleaned it and put some plain light brown lithium soap grease. Not bad.

I bought the mount from him and after a couple of years I took it apart, cleaned it and greased the mount using dark grey/black MoS2 (molybdenum disulfide) grease.
It moved smoother and was tad harder to spin by hand, but nothing to create any problems until I found that on cold nights (-5C - -10C) it became a tad too stiff for comfort, although the grease is advertised as being good down to -30C

On the other hand a friend of mine with a HEQ5 mount had serious problems taking guided astro-photos - although guided, the guiding seemed to be uneffective, with random movement observable in the guiding logs and graphs, and, after my recommendations, we took his mount apart, cleaned it and regreased it with MoS2 grease. So far I've heard of no complaints from him, he couldn't believe how much smoother the mount moved after this. Guiding finally works as advertised He hasn't been yet out under very low freezing temperatures, but I'm waiting for his experiences...

I cleaned my mount again and I regreased it using Weldtite TF2 Bike Grease w/ Teflon. At room temperature the mount moved better than when greased with MoS2. But at one point I have took the mount outside in the field, where it stayed untouched at -10C for about an hour. It was stuck. Just like it feels when the RA/DEC brkes are on. So a big no-no.

Next, I concocted a mix from this TF2 Bike Grease with TF2 All-Weather-Lubricant oil w/Teflon, with about 1/5~1/4 oil/grease proportion. It's a delicate operation, there's always the risk that some oils and some greases might not mix, or they might turn into a puffy mayonese, but they did pretty well. I came up with something as consistent as low-fat-sour cream.

I cleaned the mount again and regreased it with this thinner grease. After that I left the mount outside, exposed at about -15C for 1.5 hours. It still moved by hand, it was a noticeably stiffer, but by no means was it stuck. I've been a week ago with it out in the field at about -5C - -10C for one night and had no problems of stiffness.

All of the above has spanned over a few years, and meanwhile I read a lot about greasing, greases, soaps and additives, and IMO the best additive for a mount might be PTFE/teflon. The other 2 main grease additives, i.e. graphite and MoS2 are at their best effectiveness at way higher temperatures and pressures than we might encounter even under the harshest weather conditions. Also, the best classes of grease viscosity would be NLGI 2, 1 or lower. Suberlube with PTFE/teflon is an interesting solution, also Molykote 3451. I haven't got a chance to use them, see them at work, or hear directly on how they behave, but they would come in first as my options, if they were really easy to purchase for me.

If one has an observatory installed mount, that is being exposed 24/7 to outside temperatures, with large variations between summer maximums and winter lows, then it might become a bit more complicated. where I'm from, that means 35C~40C maximums in the summer and -20C ~ -25C lows in the winter.

Hope this hepls

[Waldemar]

I use teflon (PTFE) as long as it exists for almost everything that moves.
My favorite is FIN 25 PTFE grease in a spray can with a green 'label' on it. The can with a red 'label' on it is more oil like. SuperLube works great as well.

The main advantage of PTFE is that is has a negative friction coefficient, meaning how tighter the fit, the better it works, it fills up the unevenness of the surfaces and it is not influenced by temperature.

[Dave In Vermont]

A person I knew packed the bottom-bracket on a bicycle with Volkswagen Constant-Velocity Grease. It was molybdenum-based. The BB seized-up tighter than a drum! I opened it up and found this grease had turned into a solid plastic material. I had to chisel it out with a small chisel & hammer. It left me a nice cast of the bottom-bracket, races, bearings, and all.

Not recommended.

Dave

[cardconvict]

On 11/02/2016 at 15:06, zicklurky said:

I've been using lithium TF2 grease for my HEQ5, but I've started noticing the mount gets a bit stiff when it gets cold. It was -2 and frosty last night and when loosening the clutch on RA it hardly moved when moving RA by hand. Guiding was working, but was much worse than at the start of the night.

Any thoughts on  better grease type? 

Is this the same grease that astrobaby recommends as I going to be stripping my mount soon following here guide and have purchased this grease

[mirceaar]

20 hours ago, Dave In Vermont said:

A person I knew packed the bottom-bracket on a bicycle with Volkswagen Constant-Velocity Grease. It was molybdenum-based. The BB seized-up tighter than a drum! I opened it up and found this grease had turned into a solid plastic material. I had to chisel it out with a small chisel & hammer. It left me a nice cast of the bottom-bracket, races, bearings, and all.

Not recommended.

Dave

I'm no expert on bicycles, but AFAIK, you never pack gears with grease, unless it's clearly specified. Otherwise, use the thinnest layer possible, when it's possible.

MoS2 grease works better at very high pressures - you might get that in an automobile constant-velocity joint - and high temperatures, I believe it's the additive recommended for the highest temperatures attainable in a greaseble gear

One can find on the internetz on ball bearing manufacturers sites like SKF (blumming expensive ones...) calculators for grease quantity needed for a certain bearing, and for the strike bearing on the RA shaft on EQ5 that is like 35x50x5mm they recommend 1~2 grams of grease.

[Physopto]

What ever grease you do use stay clear of normal high pressure types such as EP. The normal car types contain Sulphur ( extreme pressure additive), it reacts with brass or phosphor bronze to eat away the metal, THUS DAMAGING YOUR GEARS.

Edit taken from one site on the internet: http://www.machinerylubrication.com/Read/28958/ep-additives-effects

"EP additives that contain sulfur cause the most damage to these types of metals. Two different types of sulfur may be used within these additives. The first type is active sulfur. Sulfur in its active state readily reacts with metal surfaces to form a ductile metal soap that is sacrificial and allows opposing surfaces to contact one another with minimal damage. Active sulfur is chemically aggressive, and with yellow metals being softer than steel, they can begin to pit and form spalls due to this chemical attack."

Derek