Disassembling an AZ EQ6 GT?

[Mark_C]

Hi all,

Has anyone successfully managed to disassemble one of these mounts? I know they're relatively new and most owners will have not had the need to open them up but I am trying to retap the thread for the RA worm positioning grub screw and the whole mount needs to be in bits to avoid swarf falling in to the gears. I can't see a single guide online about disassembly of these particular mounts and the excellent disassembly guide on Astro Baby regarding the EQ6 doesn't really apply to these mounts as the layout is quite a bit different.

Disassembling the Dec axis was very easy but the RA is next to impossible. Where the counterweight bar goes through at the bottom of the RA axis, there looks like a retaining nut with 4 holes at the bottom, looks like a special keyed instrument has to fit inside the holes, bit like a grinder key. I think removing this retaining nut is the only way  to get to the RA axis and with the clutch being surrounded on the outside, it's impossible to get a oil filter wrench on it. I really don't understand why they make it so difficult to take the RA part of the mount apart when the Dec part is so easy, it just seems utterly stupid.

I've tried putting some m4 bolts inside the holes and running a piece of angle iron in-between but it just won't shift, ends up the bolts just bending and starting to mash the holes up. Now with attempting to loosen the retaining nut, the RA clutch is so tight that seems to be seized and impossible to release, I even managed to snap the RA clutch lever in the thread, luckily I managed to extract the loose piece of thread. This is whole charade is starting to turn in to a bit of a nightmare really and I'm getting really frustrated with it.

I am tempted to going to go back to an NEQ6 and get a belt mod done on it, I never had any issues with mine many years back and looking back I wished I had never sold it as it worked perfectly.  I seem to be having nothing but trouble with this AZ EQ6 and these events have just added further unnecessary frustration. Perhaps I have been unlucky.

Anyone have any ideas ? My brother is an engineer and is going to have a look at it tonight but I want to avoid further hiccups. I should have really left it till then but you know what it's like, impatience sets in and you want to get the job done.

If someone has successfully managed to disassemble one of these mounts, any advice would be appreciated on what steps we should take next.

Mark.

[Mark_C]

Following on from my first post, I have successfully managed to dismantle the mount after a nightmare of a time and with some help. The retaining nut that I was talking about with the 4 holes inside the chrome clutch is actually held in by 3 grub screws around the perimeter of the nut. Do not try and remove this nut without loosening the grub screws or else you will begin to strip the thread on the shaft and potentially jam the clutch (like I did!). I really wish there was more documentation about this online as it's frustrating having to be a guinea pig where schematics should really be freely available to avoid things like this happening. Access to the grub screws is gained through the threaded holes of the clutch which you have to rotate until you see the holes beneath line up, I think the grub screws have a 2mm allen key head. The nut should not be difficult to remove once the grub screws have been removed.

I have successfully managed to tap a 5mm thread from where the old thread was stripped for the RA worm alignment screw and have installed a larger grub screw,  this should make fine tuning the worm position more precise.

It is quite shocking how much swarf is present in the worm/gears from factory, I'm pretty sure this will have an effect on the accuracy of the mount.

I'm currently waiting for isopropyl alcohol to arrive on Monday so will clean everything up and remove the old grease, remove the swarf and put some TF2 lithium grease in its place, this should make everything smoother. Hopefully I should be able to remove the RA backlash completely once reassembled.

I will try and write up a guide for dismantling/reassembly, as explained before the internals are quite a bit different than the EQ6 so it would be best not to use existing guides as a basis.

Mark.

[ollypenrice]

If only they would put a hundred quid on the price and make them properly. So near and yet so far.

Olly

[Zakalwe]

To be fair Olly, the OP damaged the thread through his own lack of mechanical skills (see his other thread). Further damage was caused by incorrectly dissasembling it. You could hardly claim that a BMW was poorly built if an owner decided to adjust the engine without much in the way of skills, and then tried to fix it with no workshop manual and cobbled-together tools.

No offence to the OP.....personally I would have sent it to someone like Graham at Astrotec. He knows what he is doing and is geared up to fix things properly.

[StarryEyed]

A BMW is more like a 10 micron than a synta. Sadly when materials fail and contamination is discovered during the fix and a lack of support or information is a available this reflects on the whole. But its still fair value for money.

I' sure the mount will work all the better for a strip and clean, synta's always do.

[StarryEyed]

I wanted to buy one of these mounts for nearly a year but have vowed not to buy another mount from synta which doesnt leave a lot of options I know. If Haynes did a manual for one I would probably jump in.

[Mark_C]

Don't get me wrong, they're very good mounts but there are definitely issues that need to be sorted out, irrespective of whether I have a deficiency in mechanical mindedness. 

The RA axis had quite a significant amount of play/backlash and this is what really caused the set of events that led me to having to open the mount up to begin with. I must have been unlucky as most people seem to have no issues with these mounts. As mentioned before, the amount of swarf present in the RA mechanism was shocking, it was like running sand along my fingers, this should not have been there to begin with. 

The clutch lever should not have snapped off either, the metal used for the bolt is very brittle. I accept that force should not have been used to release the clutch but the bolt should not have snapped like that.

Regarding disassembly, a simple one page PDF with an exploded diagram of the mount internals and screw placements would have been helpful. My brother and his mate who are skilled engineers were alarmed by how difficult was to open up. Without having any sort of idea of what to look for, you end up having to be the guinea pig unfortunately and things can go wrong very quickly when you have nothing to work from.

[Zakalwe]

A BMW is more like a 10 micron than a synta. Sadly when materials fail and contamination is discovered during the fix and a lack of support or information is a available this reflects on the whole. But its still fair value for money.

I' sure the mount will work all the better for a strip and clean, synta's always do.

Even a Jawa can be knackered by taking it apart without the correct tools and procedures.

I hope that you get it sorted. I know only too well (from years of messing with motorbikes) that sinking feeling of "I'll just nip this up another touch" and feeling the threads strip. :sad:

[Tinker1947]

Might be the right time to rethread the other grub screw to 5mm while its in bits......

[Mark_C]

Even a Jawa can be knackered by taking it apart without the correct tools and procedures.

I hope that you get it sorted. I know only too well (from years of messing with motorbikes) that sinking feeling of "I'll just nip this up another touch" and feeling the threads strip.     

Thanks, hopefully this time tomorrow it will all be reassembled and back in working order. Just need to find a replacement clutch lever now!

It was certainly a heart stopping moment when the thread stripped, I can tell you that!

Might be the right time to rethread the other grub screw to 5mm while its in bits......

This sounds like a good idea, in fact I'm tempted to rethread the Dec axis grub screws too, should hopefully prevent this from happening again!

[StarryEyed]

Mark_c

Did you photograph the strip down?

[ollypenrice]

I've got two EQ sixes and they work remarkably well. I'm not really knocking them but the fact remains that I would rather have spent another hundred quid on the finer details of finish, like having a properly cleaned interior. Also providing proper instructions regarding maintenance etc would be a simple courtesy to their huge customer base. I don't see myself flinching on either of these points.

Olly

[Mark_C]

The mount is now back together and working perfectly! Virtually no play in any of the axes and sounds a little better with the TF2 lithium grease too.

Before the disassembly/tweaks I could not achieve over 5 minute guided subs, now I can get 20 mins without issue. Something was obviously not right and it was difficult to determine where the issue lied. I am glad that I opened up the mount now, it was a great learning process, even if it was daunting. Doing so also means I can repeat the same steps if necessary as I know how the mount is put together.

My PHD graphs are nowhere near as wild as they were before and am getting a guiding RMS error from between 0.18 - 0.25/ or 1.10-0.80", depending on the part of the sky being imaged, not too bad!

Mark_c

Did you photograph the strip down?

Sorry for the delay in response. I have taken some photos and will try and get disassembly/reassembly instructions written as soon I have the time.

I believe the way in which the mount is tweaked (worm gear removal/meshing, bearings etc) is very similar to the EQ6 so this aspect still applies from Astro Baby's tweaking tutorial.

I've got two EQ sixes and they work remarkably well. I'm not really knocking them but the fact remains that I would rather have spent another hundred quid on the finer details of finish, like having a properly cleaned interior. Also providing proper instructions regarding maintenance etc would be a simple courtesy to their huge customer base. I don't see myself flinching on either of these points.

Olly

I totally agree with this. I would be happy to spend extra £ to avoid the cost cutting that certain aspects of these mounts have evidently suffered from. It's just the silly little things too and you wonder why on earth they carry shipping these mounts with parts that won't stand up to the task. It would be great if Skywatcher shipped their mounts with better bolts, larger knobs and sturdier levers. The AZ EQ6 GT does improve on many of the shortcomings of the EQ6 in this regard but there are still things that need improvement. A stronger and larger clutch release knob that doesn't snap off like kindling is a good example (there's an M6 bolt for that :lol) and larger saddle release knobs, the existing ones are just too small and fiddly, especially when it's cold. The maintenance aspect is something that should be addressed too, I almost ruined my mount due to misunderstanding how it is assembled and without any prior guides written on this I was going in blind. It was only until I had a few other people look at it that we could determine how it was put together.

[RegMaster]

There are some photos of this?

[RegMaster]

bump

[clarkent]

Hi Mark_C

Loads of info in your posts, thanks.

Any update on that disassembly guide or photos which you mentioned?

T'would be a great help to other AZ-EQ6 users.

Cheers

Andrew

[Astro_Baby]

I offered Synta an option to do a guide for the AZ EQ6 but they never responded.  They asked for the rights to post the other guides but we couldn't come to an arrangement.  I offered as part of that that if they would loan me an Alt Az EQ6 I would do a complete strip, rebuild and tune guide but never got a reply.

Shame because in time it will become useful - altruistic as I am I am not inclined to buy a mount just to have the guide made available.

Crazy really that for a few quid they wouldn't  play ball but hey ho.

[Starflyer]

I've owned one of these for about 18 months now and below is my experience.

It arrived with a significant amount of DEC backlash, not just a bit but enough that I could rock the DEC axis back and forth.  I've adjusted it out now and it guides well in both RA and DEC.  It wasn't difficult to do but shouldn't have been like this out of the box.

The thread on the altitude adjuster is far too course and the side handwheel nuts to lock the altitude axis do almost nothing to lock it in place.  I added leather washers underneath the handwheel nuts and they now hold the altitude axis firmly.  I can't do anything about the altitude adjuster without resorting to having one made and it's more an annoyance than a show stopper so I live with it now.  A finer thread would allow accurate PA to be achieved in less time while drift aligning, at the moment I find myself often overshooting the sweet spot, even with the finest of touches.

Out of the box the eyepiece on the polarscope rocked back and forth around half of its FOV, the thread fit between the two parts was terrible and initially any sort of half accurate polar alignment was impossible.  I eventually added some PTFE tape to the threads, realigned the polarscope reticle and now it works very well, however the PTFE tape is breaking up and has started leaving particles all over the reticle.

The RA clutch bolt bent within the first couple of uses and after reading reports of them snapping on SGL I replaced it with a stainless bolt.

Am I happy with it?  I was initially very disappointed; out of the box it was a pig to use and it almost put me off imaging completely.  I'm happier now I've got it tuned but I can see how these QC issues would immediately put other people off for good or cause them to fiddle and cause additional problems.  I guess 'you get what you pay for' holds true at this level too, this is certainly a lot of mount for the money but with a little bit of extra care and attention to detail this mount could have been a game changer.  Synta have gone some way to addressing the 'standard' EQ6 Pro problems but IMO have stopped just short of making an outstanding mount.

Cheers,

Ian

[jambouk]

Yes I broke my RA lever, but am using the replacement FLO sent me. I like ht eidesa about the leather washers and will get some. Agree totally about the elevation adjustment, far too course (and stiff), but on the whole I do love it.

James

[jambouk]

There is lots of play of the altitude adjuster in its housing, the machining is pretty precise. We are trying to work out how to remove the barrel the bolt goes through to see if we could get a new one machined.

James

IMG_4964.MOV

[jambouk]

Managed to take it apart and look at the play. Going to esquire how easy / expensive it would be to get a really snug barrel machined to replace the original with.

[Dave Lloyd]

How far can you go "cleaning and adjusting" your brand new £1300 purchase before you invalidate the guarantee?

[Gembol]

Any news on disassembling our mounts?

[mikeobrien]

Maybe just posting the pics of the dissembled mount would be good if its proving too time consuming to add a writeup.

[Gembol]

I totally agree with you. Some pics will be good enough.

Thank you!