Eq6 bearing upgrades

[MG1]

Hi guys,

I was wondering if anyone here has used these guys for bearing upgrades on their mount or if there is anyone offering these parts in the UK?

http://www.deepspaceproducts.com/default.asp?Q=HyperTune

Their hypertune kit sounds interesting but before I void my warranty I thought I'd check here first.

I should point out that this mod also works as an offering to the cloud gods. As soon as the mount is stripped bare, clear sky will present itself.

Cheers

Michael

[George]

Way overpriced IMHO, I got new SKF bearings for the worm wheel off Ebay for a couple of quid a pair, the teflon lube was around a fiver from Halfords.

The worm wheel bearings are the only ones that do any appreciable work, the 2 thrust and other 6 and should last the lifetime of the mount. It wont do any harm to replace the bearings if you have the budget to do this. Below is what you need.

SKF 6008 2RSJEM x6 (3 on each axis)

SKF 608-2RS x4 (2 on each worm shaft)

SKF 30206-J2Q x1 (DEC shaft thrust bearing)

SKF 32208-J2Q x1 (RA shaft thrust bearing)

These are the standard bearings part numbers, you can of course go ceramic etc.

Replacement shims I got from Doug Dieter in the US, his email is

skygazer@kennaquhair.com

Replacement worm and gears can be bought from Richard Gierlinger info@gierlinger.cc these are around 300 euros per shaft.

[MG1]

WOW Thanks George!

That sounds like exactly what I'm after.

Could you tell me if you noticed and appreciable tracking improvements and give me an honest/frank opinion as to whether this mod is worth the effort?

I'm fairly proficient with tools but don't want to do anything that might involve too fiddly technique and risk scrapping my mount...

Also, did you manage to find a source for the plastic bearings that the hypertune replaces with teflon discs? (or are these the shims you refer to?) Do you know how many are required, or does this vary from mount to mount?

Hope you don't mind the questions, and thanks again.

Michael

[George]

Ive edited my original post for the shims etc.

Our very own Daz has a pictorial of the stripdown Picasa Web Albums - Daz - Mount

On the older mounts 2-3 years old it definitely makes a difference as the grease used in these older mounts left something tobe desired. The newer mounts I believe these problems have been resolved. If your mount is giving you no problems I'd say leave it alone, if your using your mount purely for visual you wont notice much difference if any. If your imaging you should see a smoother tracking graph.

[Bizibilder]

Do you really want bearings capable of 38000rpm!! At $50 a shot? I think not.

You can get exellent quality, new bearings of the sort of sizes you require for around £3-£4 each. (The ones listed above with "2RS" in the code are rubber sealed - to keep the muck out. Not sure exactly the thrust bearing codes, SKF is the manufacturer. )

Yellow pages will give you a local supplier or try:

Arc Euro Trade

(usual disclaimer)

[MG1]

Thanks Guys.

My mount is a newer NEQ6 and not having any issues so to speak, just would like to squeeze every ounce of performance from it.

The mount is for imaging so I'm considering doing this mod, but might stop short of replacing the worm gears.

I did like Daz's photos. Very helpful....but slightly worrying that there aren't any of it going back together!

In your experiences does the reassembly require lots of tweaking to get the right tensions when doing it all back up? EG, if you have undone the grub screws and unscrewed the counterweight collar, when you reassemble is it just hand tight, firm, as tight as possible by hand?

Just wanting to be as prepared as possible before starting down this path.

Cheers.

[Astro_Baby]

Cant speak for the EQ6 but I have stripped and tuned an HEQ5 which is broadly similar. There are some more EQ6 strip down guides here Other resources for the Synta HEQ5 which may help. Theres also an HEQ% strip down - its not identical but may give you an idea of whats involved. The two mounts are similar in design.

I found the HEQ5 to be not that hard - and I was working from a very primitive guide with no pics at all !!!! Reassembly is simple enough IF you keep decent notes - I have done the job for any HEQ5 owner by fully documenting the strip down and rebuild but you still need to make the odd note about stuff.

Generally speaking if your proficient with tools you'll have few problems. The real embuggerment is tuning the worm gears afterwards. The worm end float and engagement setup is simple enough to do but VERY tough to get right. I had to do the process maybe a dozen times over two days to get it right (and I'm still not 100% happy - maybe 99.9% happy though ). Its just very fiddly as you have to keep making adjustments, push the mount a bit to see if theres any slack then run the mount through 360' for the axis your working on to check theres no binding on the motor/gear arrangement. To get the optimum psoition between least slack and no bind just takes a lot of time and patience. I'd suggest get someone on hand to make tea and do your rollies for you while you mess about with it

Was it worth it ? For me it was. I learned a lot from it, the mount also runs smoother and theres no play in the mount and the motors quietened down a lot from it. The mount is silky smooth to use. Inside mine - which is a fairly new one - the grease was ok but there was a surpising amount of manufacturing debris in the mount. It worked ok before rebuild but it works a lot better afterwards.

[George]

Hardest part is getting the gear mesh right

Here's a few links of interest, some are in German and Italian, just put in babelfish for translation:

Google Translate

Synta EQ6 Tuning Nightmare

Atlas Mounting Re-Work

Tim's Blog: April 2007 page down a bit

EQ6 : Atlas, EQ6, SkyScan & SynTrek Mounts

[gary1968]

I ahve just today finished tuning my CG5GT. It was fairly easy to strip, clean, regrease and rebuild. I spent the best part of an hour setting the worm backlash though, it was a b****r to get right. I think I have got a good compromise in mesh between the tightest and loosest parts of the worm, time will tell.

This is the 2nd time I have done this mount. I did it a few weeks back as I was having trouble guiding. When I did it the last time I used Castrol Lithium grease when I put it back together. Although the problems with guiding were solved I was not happy with how 'tight' the dec axis felt. I put this down to the grease being too thick / sticky so decided to do it again. I did this today and this time I used some 'Food Safe PTFE' grease which I blagged a wee drop of from work. It feels a lot better now, just have to wait on the sky clearing to try out guiding agian.

So, the moral of the story, Its not just about the bearings / shims etc. The choice of grease is critical as well, what do you guys recomend for this?

Gary

[MG1]

Ummm.... the plot (or grease) thickens!

Gary, what exactly is involved in setting the worm backlash? Sorry if it's a stupid question, but is it an allen key on a grub screw job or is this where it's necessary to measure precisely and get shims in?

Is that what George was talking about when he mentioned the gear mesh?

Still, I like the idea of being able to service my tools myself, so maybe I'll just put it all down to experience and dive in!

Michael

[daz]

There are no photos of the re-assembly for the main reason that my photographer was not available and I needed to get the mount back!!

That said, I will get round to doing it. Also note that the standard EQ6 is different to the EQ6 Pro - only slightly, but doesn't really affect the re-assembly process.

As to the gear mesh, it is the alignment of the motors to the spur on the worm shaft. Its not a shim job - that is for aligning the worm with the worm gear.

The two housing have opposite facing grub screws which allow the fine movement of the housing against the worm.

The motor housing needs stripping out, the housing loosened and then you can adjust the mesh.

You need to run the spur through a couple of revolutions to ensure no tight spots, but you should be able to reach a position of little or no play.

I'll write up a fuller description if anyone would like.....

[gary1968]

Ummm.... the plot (or grease) thickens!

Gary, what exactly is involved in setting the worm backlash? Sorry if it's a stupid question, but is it an allen key on a grub screw job or is this where it's necessary to measure precisely and get shims in?

Is that what George was talking about when he mentioned the gear mesh?

Still, I like the idea of being able to service my tools myself, so maybe I'll just put it all down to experience and dive in!

Michael

Yes, allen keys are all thats required. When setting the backlash you are looking at the 'free play' between the worm gear and the worm ring it drives. You start anywhere, I started where it lay when I rebuilt it, set the backlash so that there is just a little free play between the gears. You do this by setting it then 'rocking' the worm gear back and forth a little, you should feel a little slack before the ring engages, only a tiny bit of free play is required. Then tuning the worm gear by hand feel how tight it is. Stop every turn or so and check the free play at thet point. If it is too tight back the mesh off a little until you feel a bit of free play. Do this all the way round the ring for the full 360 degress. Then do it again and again. You are aiming for the mesh point where at the loosest point you get the minimum backlash while at the tightest point you want no backlash without binding the gears. I spent just short of an hour today turning the worm hear for the dec axis by hand checking and adjusting 'till I thought it was the best I could get. I think you could go on with this forever but you just have to eventally call ENOUGH and stop fiddling..........

SO, gear backlash is about compromise as there will always be inaccuracies in the gears production. Having said that though, my CG5 is at the cheaper end of the market while the Sktwatcher mounts are reportedly better made. So there might not be such as big a problem in seting the backlash.

I was lucky I think. According to the graphs on PHD Guiding it was only my dec axis that was a problem, so thats all I 'tuned'.

And yes I think thats what George was on about.

I hope that makes sense mate.

Gary

[gary1968]

Now, after reading what Daz wrote it might be that the construction / adjustment of these 2 mount is completely different. So, as Daz is referring to your exact mount then I'd go with him........

Gary

[MG1]

Thanks for the input Daz, your photos of the disassembly are excellent and really show what's involved.

I'll try and do somthing similar with mine if I get the confidence up to have a go.

If you've got time to do a full write up that would be great, but I'm not in any huge rush. I'm just thinking it through at the moment and want to see how the new more ridgid bars impact on my setup first before I try this.

Michael

[MG1]

Cheers Gary, that popped up while I was posting. I love this forum for that. So much knowledge out there!

[Astro_Baby]

If you have a look at my HEQ% strip down guide it will give you an idea of whats involved in setting the worm engagement. The EQ6 from what I have seen is not much different.

[MG1]

Cheers AB, great site btw.

[Astro_Baby]

No worries - as I said in earlier post - its fiddly and, at times frustrating, rather than technically tough. Changing a clutch - now thats hard work. Compared to that any astro-mount is a doddle.

[m.tweedy]

Hi guys,

but before I void my warranty I thought I'd check here first.

Michael

Wait until you are out of warranty before attempting this Just in case anything else was to go wrong with the mount befor expiry.