The much promised EQ6 strip down guide.....

[MickyWay]

Hi Neil,

I noticed Mel used a lithium based grease in her strip down guide, and it does seem to be the recommended type on the forums.

I'm a cyclist of some 50 years, racing and social, and I've used all sorts of grease, but had no experience with Teflon stuff, although it ticks the right boxes, got to be better than no grease, black gunge grease and metal chaffe.

Regards,

[Astro_Baby]

HER strip down - (I is a girl LOL - but ta for the priase on the guide - does a twirl and skips a bit LOL ) Anyway Teflon grease - no idea. The CN crew always advise either lithium or the serious spannerheads reccomend this stuff Loctite | Workshop Consumables | Lubricants, Greases and Cutting Fluids | Precison Lubricants | Loctite Superlube® |399420 which is a PTFE lubricant and super duper stuff. I'm not sure its worth it myself.

My own gut feel is lithium kept my old bike going in rain or shine for about 10 years so I figure its good enough. I dont know of Teflon grease has any downsides at all.

You have to be a bit wary because some oils and greases will mess up polycarbonate plastics easily and there are plastic bits inside the mount. Some lubes will also eat PCB material and so will mess up circuit boards quite well. Teflon should be safe on that score I would think.

I'm surpised they dont have lkithium in a bike shop - granted Halfords are useless - but I have three bike stores near me and they all will happily sell you a monster sized jar of Lithium grease for a few quid.

[great_bear]

Mel,

I suspect you might have *some* idea how useful this kinda stuff is, but maybe not fully

- Truly a Godsend to those who need it...Such good work...

[MickyWay]

Sorry Mel, message amended...............

Regards,

[Astro_Baby]

LOL Colin - no offence at all really - quite funny really

[Euan]

Thanks for this, I did it before you had written this up and wish I had waited now, would have saved myself loads of this --->

It's made me think I was doing the worm adjustment wrong. I was moving the small allen keys adjustments and then manually moving the motor gear with the motor removed with my finger until I was getting it as tight as possible without binding. Is this the same thing you describe?

I've never done the worm float adjustment I will give that a go aswell.

[daz]

@euan - yes, that is correct for the worm adjustment

[Astro_Baby]

Colin/Mickeyway - you have private messages blocked - thanks for your message but I cant reply unless you unlock private messages.

Mel

[MickyWay]

Colin/Mickeyway - you have private messages blocked - thanks for your message but I cant reply unless you unlock private messages.

Mel

Unlocked, I think!

[Euan]

@euan - yes, that is correct for the worm adjustment

Thanks, done the worm adjustment again last night and no wonder I was getting dodgy auto-guiding. Dec was too loose and RA was too tight!

[ncjunk]

Hi,

Half way through stripping the RA and bought a rubber oil filter remover that made the RA nut easy to remove...I was a bit worried as it seemed very tight but once it started it was fine.

So 20 minutes in and I have everything almost stripped but I had a question for later. When I re-assemble the roller bearings in the brass worm gear it says apply a small amount of grease to the edges...would that be the sides with the dust covers on or those and the circumference of the bearing, i.e. a bit of grease all over?

Thanks in advance.

It all seems to be quite well greased and almost exactly as per the photos. The grease n there is an opaque/translucent whitish grease.

I am hoping that by setting this up using the instructions I can cut out some of the nasty spikes in the RA I was getting. I don´t mind inconsistencies in the RA but I would like to be able to guide them out!

Neil C

[russ]

You certainly like to get stuck in Mel. Not afraid to take on anything.

It's a great guide. I don't even own an EQ6 but still had to take a look.

[yesyes]

You certainly like to get stuck in Mel.

Hm... You might want to rephrase that ...

It's a great guide. I don't even own an EQ6 but still had to take a look.

hehehe... Me too... I'm hoping I can use some of that info for my CG5-GT. I'm just wondering whether I should wait for the warranty to expire before taking it apart.

[ncjunk]

i have found a major error in the guide...where it says to put the

mount on a towel to stop it getting scratched could you change it

to .."put the mount on a towel but make sure it isn't one of the best

ones and a gift from the mother in law"

sigh, all i was thinking was that the extra fluffyness would be great in protecting the mount....doh!

[Astro_Baby]

Ah well as for towels I get stick as well if its any consolation.

The bearing edges (question up top) the bit the grease goes on the bearing face (where the dust cover is) but you may also want a bit on the circumference to help ease bthe bearings back in - not too much though.

Taking stuff on - the biggest thing I ever stripped was a Bristol Orpheus jet engine. Oddly there wasnt much to it really. Course I only had the main block not all the fuel systemes or engine electronics to worry about. Some silly fool had left it out in the rain for about 20 years.

[ncjunk]

Thanks for the reply.

One of the grub screws got stuck on the motor gear..I got the bearing out and then managed to soak the motor gear in boiling water for five minutes (hoping the metal would expand a bit) and that seemed to free it. I was a bit worried as if I couldnt get the gear off I couldn´t remove the worm.

The bearing on the other side of the worm doesnt seem to want to come off but I may just leave that on there as I can clean what I need to with it in place.

Thats the great thing about this everyone has different problems! my RA main nut was easy but the grub srew a pain.

As Mel says in the guide take your time and think things through...fairly easy though as long as you don´t start bashing things.

Lets see how the reconstruction goes.

[Astro_Baby]

Yup - there are tone of problems in the strip down. The one I did had some serious issues mainly;

RA nut was done up so tight my standard flex wrench failed to shift it. Large stillson wrench just slipped - in the end I bought an oil filter wrench and even then we had to go metal to metal and it took two of us to get enough pressure to remove the nut.

Worm end float covers - two person job, couldnt believe how tight they were done up.

RA main bearing and worm gear - got jammed during removal and had to be very gently drifted using wooden mallets and it took ages to get it free.

The small worm bearings can be tapped out using a screwdriver handle againts the bearing and gently tapping the tip of the screw driver OR use a wooden dowl. So long as whatever is in cobntact with the bearing is softer than the bearing (ie wood, rubber, plastic etc) AND you exrecise care you should be ok. To be honest of the bearing is stuck and it appears smooth running and well lubed you could leave it in situ if needs be.

[ncjunk]

I am stuck at the re-building stage.

I have put everything back together but can´t get the RA turning. So I have removed the motor and the problem I have is the worm gear appears to be able to move in and out along its axis (i.e. through the bearing).

Also the motor gear when rotated in one direction moves the mount but in the other direction seems to move the worm out instead.

I am following the adjustment instructions but I must have made a mistake somewhere, could having the motor gear on the worm flush against the larger section of the worm (instead of set back slightly) cause the problem?

it is the worm moving in and out along its axis which is confusing me....

[Euan]

I am stuck at the re-building stage.

I have put everything back together but can´t get the RA turning. So I have removed the motor and the problem I have is the worm gear appears to be able to move in and out along its axis (i.e. through the bearing).

Also the motor gear when rotated in one direction moves the mount but in the other direction seems to move the worm out instead.

I am following the adjustment instructions but I must have made a mistake somewhere, could having the motor gear on the worm flush against the larger section of the worm (instead of set back slightly) cause the problem?

it is the worm moving in and out along its axis which is confusing me....

Have you put the worm brass gear in the right way round? I did it wrong the first time and the whole thing wouldn't line up right and it was moving back and forward as you say

[Euan]

I'm just pondering whether it's really worth greasing the gear parts of the mount

I can see the point of greasing up the bearings and other rotating parts, but for the worm and the motors gears, do these not need to be high-contact with no substances in-between? Would this not make them more likely to get full of dust particles, dirt, paint flecks, etc?

...off to ask a mechanical engineer I know

[Astro_Baby]

Without grease they will suffer excessive wear (and will be noisy too) there is always a small play between gear teeth in any event to account for any deviation in machining.

Thats especilly true of worm gear arrangements and one of the reasons why worm gears are always composeff of a hard substance(steel) and a soft substance (brass). A steel to steel arrangement would jam very readily unless there was a massive amount of play. In essence the steel worm remachined the brass gear in a small way. Worm gears allow a tremendous amount of weight to be shifted for very litte power (thats why this dinky lil 12v motors can shift the mass of a telescope) but the price is a relatively loose and wild gearing arrangement.

I'd not run it without lube as the gearfaces should be a papers thickness apart anyway.

[Euan]

Without grease they will suffer excessive wear (and will be noisy too) there is always a small play between gear teeth in any event to account for any deviation in machining.

Thats especilly true of worm gear arrangements and one of the reasons why worm gears are always composeff of a hard substance(steel) and a soft substance (brass). A steel to steel arrangement would jam very readily unless there was a massive amount of play. In essence the steel worm remachined the brass gear in a small way. Worm gears allow a tremendous amount of weight to be shifted for very litte power (thats why this dinky lil 12v motors can shift the mass of a telescope) but the price is a relatively loose and wild gearing arrangement.

I'd not run it without lube as the gearfaces should be a papers thickness apart anyway.

Aye, that's pretty much what I've been told and also read since online as well

I have some nice silicon grease I can use, I just need to make sure this time around I get rid of all the paint flecks to stop it all getting caught up in the grease

[MickyWay]

Here are my experiences of a recent HEQ6 Pro strip down and tune:

The mount is only 2 years old, but because it is permanently left outside mounted on a pier, I felt that an overhaul would be a good idea.

Strip down

There were no overly tight fastenings, so everything came apart easily.

(With one exception, but more about that later).

There were no signs of paint on bearing surfaces, and the general internal finish and machining was acceptable.

Lubrication was adequate, and thankfully, there was no sign of the black gloop used on earlier mounts of this type.

The main bearings looked impressively large, and again were well lubricated with a decent white/transparent type of grease.

So far I was pretty happy with what I’d seen and decided a good clean and degrease would be all that was needed.

However, I decided to take Mel’s (Astro Baby) advice and change the worm gear bearings.

The bearings came out easily enough, except the RA side. The retaining nut would just not shift, despite soaking the thread in isopropyl alcohol to soften the Loctite. I decided to leave this bearing alone, changing only three.

Re-assembly was straight forward (thanks Mel).

A word of warning, don’t over tighten the fastenings. The castings are aluminium, and threads can easily be stripped.

There is no need for brute force on any part during reassembly.

Tuning

I took out most of the play in the worm gears so that only a fine tune would be required on power up.

The worm gear to main gear adjustment is very crude, and it’s crucial to get this right. Too little clearance between the gears and the mount will bind and stall. Too much and the mounts accuracy will suffer.

I found it easier to control the adjustment of the worm gear assembly

by using two opposing Allen keys working together (one tightening, the other loosening).

I managed to get most of the backlash out of the Dec axis, but the RA axis needed a bit more clearance to prevent overrun due to slight binding.

All this was done with no load on the mount, and then repeated with weights and scopes added.

Conclusion

Was it worth doing? Definitely yes.

The slewing is quieter and smoother, and the motors are more responsive and direct.

Knowing that there are no major issues with the mechanics is also a plus.

Would I recommend you do it? Yes and No.

I have an engineering background, so I felt reasonably confident that it would be a worthwhile exercise. If you have no, or little experience, and your mount works/is relatively new, then leave well alone, or phone a friend. The new generation of these mounts will go on and on, trouble free, for years.

Finally, thanks to Mel and her strip down guide, which I found invaluable

as a source of reference and inspiration.