NEQ6 Strip & Tune

[MG1]

Holy Equitorial Fork mount batman!

Nothing like the Americans for super-sizing!

[Astro_Baby]

Sy - Have tou tried tightening the big brass hex bolts on the top of the motors to eliminate the noise ? You need to loosen a small set screw on the side of the motor first by the way.

I have this with my HEQ5 - I can elminate the noise in the RA but never in the DEC in one direction only.

The DEC gear makes a particulat clank clank clank sound but only in one direction and I have NEVER been able to eliminate it.

The rebuild shut a lot of the noise off and tuning the gears did a bit more but there is still this annoying ek ek ek sound that comes out of the DEC but only in one direction aaarrgghh

In the end I just gave up and decided to live with it - its still the quietest HEQ5 you'll ever see (or hear) so I figured that was as close as I was going to get

[astroimpulse]

Hi Mel, yep...I did all of that. It's a different set-up on the NEQ's motors (grub screw holds down the motor axle/shaft) but like I said....did all that first But this is why I think maybe some nylon washers might be of help. I totally think the sound absorber idea will do the job too.

My own test showed it was an acoustic anomaly between the transfer gear and the worm gear (on mine...can't speak for others).

Exactly like you...I've decided I can live with it. I think you've mentioned in the past...it will sound quieter outside. Also it only does it on the faster slews.

But if I come across the parts I need...I'll have another go. Just can't be bothered hunting right now lol

[MG1]

Interestingly the NEQ6 doesn't have these bolts...There is a pressure fitting to hold the gear down, between some thin brass washers. This is secured with grub screws... Synta must have realised this a source of noise.

I also found this on the EQ6 yahoo group from Ed at deep space:

I am now working with Aeroquest Machining to provide high-precision worm and

ring gear sets for the Atlas/EQ-6 as part of the HyperTune service for the

mounts. These gear sets are definitely not cheap, but if you want to squeeze

every last bit of performance out of your Atlas/EQ-6 mount, they will help you

do it and you will still spend less than a mount in the next tier. Please see

the HyperTune Service Request page on the Deep Space Products website for more

information and let me know if you have any questions.

I'm still working on the spur gear issue.

Thanks,

Ed Thomas

Deep Space Products

Might be worth a note to them saying that we'd be interested in maybe pooling together for a discount. Going by what they charge for their basic upgrade kit (includes teflon spacers but doesn't include bearings and costs $135!) I can't imaging they will be cheap!

[Astro_Baby]

Sy - I think your right. In a silent room the HEQ5 sounds very buzzy. Outside with no reverb off walls its so quiet I sometimes doubt its running at all.

[MG1]

Sy, have a look at this catalogue... http://www.hpcgears.com/newpdf/hpc_cataloguesinside.pdf

I might drop them an email tmrw if I find a minute...they are UK based for a change! If thay can sort something out it would certainly cut down postage.

[astroimpulse]

Totally.

In the room it's silent up to about 6 or 7 (if I remember correctly) but then it gets rattly. Wouldn't use the higher speeds too much anyways. the tracking is actually a lovely pulsing sound.

Just wouldn't want the neighbours throwing on their flood lights at 3am wanting to know what the hell I'm doing making coffee! hehe

MG..$135 is about £85 so doesn't sound too bad. If they mark the package as 'repaired goods' then it won't get import duty. Morally it kind of is repaired goods

So that would included all the gears or just the worm (and washers)?

[astroimpulse]

Just seen your post after Mel's...lets have a look.......

[astroimpulse]

Just having a quick scan...looks fantastic! What a find *tips hat*

[MG1]

So that would included all the gears or just the worm (and washers)?

Nope..

The Standard kit includes the following:

• Set of all mount hex wrench sizes
  
  
• Screwdriver
  
  
• Selected sandpapers
  
  
• Polishing compound
  
  
• 4-40 gear set screw replacements
  
  
• Thread locker
  
  
• Razor cutting knife
  
  
• Cleaning brush
  
  
• Internal lubricant
  
  
• Access to electronic versions of detailed photo breakdown of mount and components
  
  
• AutoStar firmware upgrade cable
  
  
• DVD step-by-step video on how to HyperTune ® your mount
  
  

an extra $45 will get you JUST the worm gear bearings (4 of the 608's)

That doesn't include ANY of the main axis or thrust bearings...

Hence why I thought it was pricey.....

[Photosbykev]

Sy, have a look at this catalogue... http://www.hpcgears.com/newpdf/hpc_cataloguesinside.pdf

I might drop them an email tmrw if I find a minute...they are UK based for a change! If thay can sort something out it would certainly cut down postage.

I use this company for gear sets on simple systems but they are mass produced with fairly wide tolerances. I certainly wouldn't call them a precision company.

[MG1]

thanks for the heads up Kev....any suggestions?

I'm off to bed...gotta run in the morning!

[astroimpulse]

*SNIP*

Hence why I thought it was pricey.....

Pricey? It looks pointless lol. I thought it was replacement parts...not a tool kit! hehe

That catalogue you found is amazing. I wonder how practical delrin would be as a transfer gear. I've no idea of its wearability (not a word...but you know what I mean).

Gonna have to get the calipers out at some point

[astroimpulse]

I use this company for gear sets on simple systems but they are mass produced with fairly wide tolerances. I certainly wouldn't call them a precision company.

Shame...I was quite excited there.

Thanks for the heads-up.

[Photosbykev]

Ondrive precision spec gears are normally very consistent and for one offs somewhere like Renold have a good reputation but precision components are expensive, very expensive lol

HPC and OnDrive produce commerical grade components which will be the typical spec gearing already used in the mounts.

[astroimpulse]

I would have thought so too. I can't see Synta using the best of the best in their gears. If they did there would be no need for all this tuning

I'd love to have a go at some experimenting but I'd be lucky to get out and use the mount let alone experiment with it lol

I'm going to have a proper look through their catalogue tomorrow and I'll check out OnDrive too.

Good stuff, Kev. *thumbs up*

[Astro_Baby]

At the risk of being accused of thread hijacking I have some info and also two questions.

This weekend was rebuild the EQ6 and supertune. The rebuild has gone very well with very few problems. Unlike the two previous EQ6s this one came to pieces much more easily.

Some observartions -

No signs of synta goop, it appeared to be greased with something that looked like Vaseline. As ever there was not enough of it with the thrust bearings being almost dry.

The amount of play in the DEC was excessive by any standards having about 2' on the DEC index scale of play.

Mount was clean inside but showed two nasty piece of sharp flakes which were paint shards, these were about to let go from their home in the DEC worm cover.

This is a newer mount believed to be less than 2 years old and it was vastly better machined and finished than the two older ones I have worked on.

Its mechanical dimensions were remarkably similar to those indicated on another rebuild/supertune guide (DEC Assemble) this seems to indicate remarkable consistency of manufactur.

In fact tolerances were so good that the additional set of shims I bought off MG1 weren't needed. The mount being within .0001" from cold on its worm settings. Various measurements were taken to assess the flatnes of surfaces and its was well within good engineering spec. I measured various distances and all tied up rather well so a big hooray for Synta on this one.

As ever the mount has been vastly improved by rebuild and how has zero play in the RA (the DEC is one of the questions below). And runs virtually silent without even the start up clanky sound (Hooray for Melanie from whom all EQ6 blessings flow )

Anyway here are two questions which I am hoping you can help with.

The first question.....

On rebuild and tune the DEC axis meassurements were so perfect that no shims were required. In fact to put the small teflon washer that was already in the mount back in threw the worm measurements out by .010" so I assembled without the teflon washer. This means one bearing is directlly stacked on the other with no washer between them. (the bearings are the lower worm gear bearing against the housing bearing on the mount). Do you see any problems with this ?

It seems I can either have a bearing to bearing fitting which runs against good sense or have the worm roller to worrm gear fitting .010" out - which also runs counter to good sense. Which would you consider the lesser of these two evils ?

Post rebuild and into the tune the DEC shows a marked reluctance to run smoothly unless some play is admitted into the worm adjustment. I cant shake the feeling this may be caused by the teflon washer being left out even though it seems illgical.

Second question....

When washing out the bearings my eldest observed that when dry and not greased the bearings run much faster and asked the question'why bother greasing them - the run more freely without grease and lets face it the telescope is hardly whizzing along at many revs so why not leave them dry ?'

Its a damn good question and I cant think of an answer - any ideas ?

Right I am back to trying to tune the wretched DEC motor and silenty swearing to get a CPC 800 or a Meade LX200 where this sort of stuff isn't required

[Mick UK]

"When washing out the bearings my eldest observed that when dry and not greased the bearings run much faster and asked the question'why bother greasing them - the run more freely without grease and lets face it the telescope is hardly whizzing along at many revs so why not leave them dry ?'

Its a damn good question and I cant think of an answer - any ideas ?"

Perhaps this is the reason why yourself and others have mentioned that they come... "with hardly any grease on at all?"

Is it possible Synta know what they are doing after all?..

Excellent thread by the way, wont be long before i have a crack at mine thanks to every ones input and your website AB:)

[Psychobilly]

Have a look ZX1.... ZX1 Home

Used to use it all the time on bearings when racing RC...and those bearings where going at silly rpm's...

The V6 has also had it in the Engine, Gearbox, and a bit in the fuel to to the top half of the cylinders...

Billy...

[Astro_Baby]

Right - finally got the bitching RA DEC to play ball. It was just a bit more filddy than the othjer EQ6s but its now fettled and running sweet as a nut.

Silent, smooth and its cleaned up a treat.

[MG1]

Hi Mel, you're not hijacking...your comments are always most welcome.

That's a very good question regarding the lube...the only gears that spin at any decent speed are the motor gears and transfer. I used superlube...this is very similar to what was there to begin with.

Did you keep the existing washers then? Mine was also pretty close, but the existing washers were quite worn and obviously a cheaper plastic, not Teflon or Delrin. My mount is three years old this month so maybe they have changed the spec? I decided it was still better to swap them out though.

I also used a little lube on them to hold them in place when replacing the RA axis.

I found the RA much harder to get rid of the play but did so by loosening both worms and using the weight of the housing to position the worm gears together. I also then tightened the worm carrier retention slotted screw.

Interestingly I did end up removing the housing and repositioning the worm transfer gear on the worm axle. I had it too close to the worm gear.

Then I tightened the top grub screw (this tightens the gear meshing) until I could no longer rotate the axis by manipulating the worm transfer gear with my fingers. I then backed of 1/8 of a turn and tightened the bottom grub to open the meshing a little. This gave a little play so I just tweaked the two until I could just just the transfer gear (although not comfortably as I left it pretty stiff). I replaced the motors and check it through full rotations at speeds 3,5&9....this took a while.

No binding so all was good.

Prob worth mentioning that I did spend some time fiddling with the motor meshing. I started using some very thin greaseproof paper, but ended up using tinfoil to set the mesh. No noticeable backlash. But there obviously will be some.

Last night was first light for the modded mount and I was very impressed.

When I get home I will post a quick 10min unguided full frame image I snapped by just clamping my camera to the mount diagonal. You can all be the judge of whether it was worth the effort.

Btw, I should warm you it was a quick widefield shot of nothing in particular and not very well focused either!

Noise wise, the tracking just sounds beautiful. I could almost fall to sleep listening to the sultry pulsing... Skewing has no startup grind and just a hint of the acceleration when you select the faster speeds.

Only downside is I will now get more upset with coffee grinders!

Next:

If clear I will push the exposure times and see what it will do. Previously I was only getting 3min, so I think this is an achievement!

Can someone recommend a good method for assessing PE? I'd quite like to give it a go to see how/what can be achieved.

Will feed back after weekend again.

Cheers

[Astro_Baby]

I just left the original washers in. Apart from the dec which has no washers but i have now noticed a nasty side effect which is the dec can move up and down. Ie if you push against the collar aroind the weights the whole dec axis will move up by about .010 of an inch. This doesnt seem right, my heq5 shows none of this so taday I am stripping the dec to put the factory washers back in.

I'll let you know. iF as i suspect the problem goes away, given the fact that each one of these i have stripped has different washer configurations, it may well indicate that later mijnts are in fact tuned at the factory in which case hyoertuning is pretty much a waste of time.

I will write it all up as an online guide but with a rider that fkr hyoertuning its more an art than a science and its defniteky not for the beginner with these mounts.

Weirdly the two heq5 mojnts i have done the ra was a complete mare to set up but on the eq6 its always the dec thats a [removed word]. Maybe thats why this is the second eq6 that camw to me with way too much play in the dec axis.

[Zakalwe]

I am no mount expert, but have messed with all things mechanical for years. if I was assembling bearing for use in, say, wheel bearing use, then I would pack the cages full of grease. The bearings and rollers would be spinning fast, with high loads and require a film of lubrication*. However, the bearings in a mount are barely rotating. Their purpose is to reduce "stiction", provide a low-eccentric mechanism to allow the axles to rotate, and maintain the tolerances within the mount. I am guessing that a heavily packed bearing would actually increase stiction. Perhaps a good oil would be a better lubricant? Maybe a heavy-ish engine oil....enough to prevent rust, keep moisture at bay and to lubricate the rotating surfaces?

*Grease works by lubricating the rolling surfaces. in a car wheel running at about 40MPH, the bearings are spinning at 600RPM.The grease forms a hydro-static film, which lifts the rollers/bearings, minimising metal-to-metal contact.

[MG1]

Here's a quick snap taken last night...

I literally pointed upish, set the tracking going and set the shutter release for a bit so we could have a quick cuppa.

The data is in the exif, but it was basically:

637sec at ISO 200

Canon EF50mm f/1.4 lens at f5.6 on 5D MkII body.

In my book that's 10min UNGUIDED!

I know it's not brilliant focus, and there is a little distortion in the edges, but it looks pretty good to me. (oh and it's grossly over exposed with all the LP)

If it hadn't have been cold late and the prospect of a 6am start i'd have tried some longer ones too....maybe at the weekend.

Your verdicts please... (am happy to email the full raw file to anyone, but it is 7MB)

Cheers,

Michael

[MG1]

Just out of interest...is it possible to plot periodic error using a dslr, or do you need a CCD camera?