EQ6 - modification ?

[bojan]

Have anyone recently went through EQ6 modification (to achieve smaller periodic error, faster slewing and possibly GoTo)?
I ordered mine earlier this week (at Bintel, it is due next week hopefully..) and I am already thinking about how to improve it.. :eyepop:!!

[peter_4059]

I ordered my EQ6 upgrade kit today - hope to have it next week. You can also get the bearings replaced and regreased and the gear mesh adjusted.

[Stephen65]

Where does the upgrade kit come from?

[skwinty]

Hi All
Please correct me if I am wrong but this upgrade kit only refers to the older eq6's and not the new Synscan eq6 and eq6 pro.
I believe that the grease, worm and bearing issues have been resolved on the new models.:thumbsup:

[peter_4059]

Yes the upgrade kit is to convert the basic EQ6 into the Synscan goto version. You get replacement motors, a new panel on the mount and a Synscan hand controller in the kit. I've ordered mine from Star Optics.

Don't know if the grease/bearing issues have changed on the new models - there are quite a few websites that discuss how to re-grease and what size SKF bearings to get.

[skwinty]

Hi Peter
In my synscan eq6 pro the grease is of the clear type and not the black.
I have not checked the bearing part number. From what I understand from the yahoo eq6 forum the bearings have been changed on the newer models and these models should be ready to go without any upgrade.

The grease issue I believe only became a problem when operated in sub zero temperatures. Not a common scenario here in sunny south africa.;)

[bojan]

Hmmm
So it seems you guys are saying my new EQ6 may not need the improvement, right? (I am not really interested in GoTo, i found it not worth the trouble.. and if I decide some times to go for it, I will use bartel's software).
Actually, now I am not sure what I will get at all... I just went into the shop and ordered EQ6 (basic), because I wanted a mount that will not budge if I decide to load it with my newtonian (~13kg).

[iceman]

I have my 21kg OTA on an older EQ6 and it's fine.

Though i'd like Don at Bintel to give it the upgrade/re-work to make it better, but I don't have too many faults with it. With the ED80 on and guiding it performs flawlessly.

[peter_4059]

Mike - do you have the goto-ready version or the basic EQ6 (no guide port and different motors?) Also do you autoguide with the 12" and the ED80 on the EQ6 at the same time? That must be pushing the capacity of the mount to the limit.

[Zuts]

Hi Bojan,

I have a newish EQ6 (8 months) and with guiding it is great. I have heard though that any mount can be made better and the EQ6 is supposed to perform much better after a re-grease and work on making the worm a bit smoother.

I havnt heard from Alex for a while but he stripped his EQ6 and tried the above. I wouldnt do it coz I am happy with its performance with guiding but from your posts you seem pretty handy so may like to give it a go. If you can find Alex's post egards this there is a good link with step by step photo's from someone who has done it.

I would get the goto version though, i dont think the price differential is that great and in the future if you decide to sell a goto mount is far easier to flog :).

Paul

[bojan]

I think Bert (Avandonk) has the modified mount with Mel Bartel's software.. And things he is doing with it are amazing :-) (well, the amazing part is mostly not due to the mount but it certainly does help a lot).
I would like to know if this mod include the removal of the second worm gear - from the photos on the web it seems that the stepper motors (in microstep mode) are driving the main worm gear only via timing belt.... but so far I haven't seen enough details on the web.
However, if this is so, it iwill be similar to my dobson, I have only 1:140 worm gear and then 1:12 friction roller reduction, plus 32 microsteps, and the result is quite smooth movement of the telescope, no PE is obvious at the high power eyepiece.
Anyway, I would like to use it with relatively wide angle (200-300mm).
Then, I will try 1000mm cathadioptric that I think is quite good (at least for visual it seems OK) but I never had a decent mount for it.
Then, maybe, one day I will have all this (including my 10" newtonian) on it, under some roof, somewhere in the country far from city lights.... ah, sweet dreams.... :-)

[iceman]

Hi Peter
I've got the goto-ready one I guess, it does have skyscan v2 and a guide port.

I don't autoguide with the 12" on - i've got a side-by-side refractor setup for my widefield imaging.

In the future i'll use an 8" or 10" with guidescope as my DSO imaging setup.

[peter_4059]

Cheers Mike - I've got the basic EQ6 but it is getting a make-over next week.

I'm interested in how much load people are putting on their EQ6 but will start a new thread.

Peter

[bojan]

OK, I have done my homework over weekend, about what & why people are modifying on their eq6's, and what is the outcome, in numbers

Summary of reasons for mod:
1) Sometimes large Periodic error
2) Large backlash (not good for autoguiding)
3) generally problematic quality of assembly at the factory.

The periodic error comes from couple of sources:
- Main worm gear (30 arcsec p-p)
- other gears in the reduction chain (1-5 arcsec p-p) and bearings (dirt in them, lack of lubricant etc)

So, belt drive is done mainly to have faster slewing when GoTo, but since the reduction ratio is significantly lowered, microstepping must be used (Bartel's software handles this nicely). The belt drive itself will not improve the PE significantly, and this is to be expected, because the errors introduced by gears closer to motors are reduced by the subsequent reduction stage anyway, so the only gear without further reduction is the main worm gear and therefore it remains as the most significant contributor to PE.
Also, belt drive reduces backlash, as all other contributors (apart from main worm gear) are removed.

To me, the biggest problem is inconsistency of test results for PE... it seems that either quality of mount varies drastically from specimen to specimen, or that the measurement results obtained by their owners are questionable. Obviously, I will have to perform my own tests and see how it goes, and if modification is necessary or not.

Outcomes of these modifications and refinements are also not consistent. Some people achieved <5 arcsec p-p with the same main worm gear, by only dismantling, cleaning and putting it back together (with more or less adjustments done to the relative position of the worm gear and worm).
Some others even changed the worm gear assembly (there is a company in Germany [Gierlinger], supplying much better quality replacement), but without significant improvement (?).

To my understanding, the error should not significantly exceed 1 pixel p-p (that assumes ideal optical system.. star images are always much lager than this).

So, for my 10" newtonian and 400D in prime focus the pixel size expressed in angle units is ~0.8arcsec. Very narrow (it will be a bit bigger with coma corrector)... Something like this is impossible to achieve without good autoguiding.

[KISA]

Hi,

Just a slight tangent... below is a link that those thinking about upgrading their HEQ5 or EQ6 scopes might find interesting.

I upgraded my HEQ5 about 2 years ago with an upgrade kit from the link below. I also changed the grease and replaced the original drive gearboxes with the more accurate Conrad gearboxes. It has added an amazing amount of functionality to my scope at a very reasonable price.

Regarding some of the questions asked below, it might also be worth looking in the forums at the link below, there is a wealth of knowledge regarding all facits of the upgrade (grease etc).

http://eq6.update.rajiva.de/

Regards,

Markus

[iceman]

Which package did you do, Markus?

I'd love to give my EQ6 a tweak but wouldn't want to break it!

[xelasnave]

I think for the first pull down if you polish the gears and "blue print" everything.. may find it very satisfactory..It is well made and robust...or in plain terms make sure everything is clean with no burrs or rubbish that should not be there is removed... things should not have burrs or bits of metal but sometimes... so it is really a case of making sure firstly it is clean and metal free... inspect the mess of the gears ..mine was perfect but they got a good buff and polish...
I am running without greese on the gears with only a very light oil cover... does it work better ...seems to but in truth it has not being properly tested..certainly "feels" better. I have mine set up such that I get a wine at high slew speeds which is not on but it is here that it works best to track..so I dont slew fast and seek the better tracking......well I think it is better because I have the gears messing where I want without regard to slewing...

It is no big deal to pull it apart..simple and one should do it ..you gotta be really at one with the machine know it, care for it, and from this you understand it..exactly how it works for one and how you can help it be better...

alex

[bluescope]

You won't have a problem with your 13kg newt. My SW 254mm newt weighs in at 14.6kg and then I hang the SBIG st2000xcm off the side which adds another kg or so with MPCC etc and the whole thing ( EQ6Pro ) is rock solid. The only thing I needed was an extra 5kg weight to balance the setup. I haven't checked inside for grease colour etc, I figure if it's working why mess with it !

:thumbsup:

[KISA]

Hi Mike,

I bought the self construct kit and assembled it myself (was pretty easy). I also paid for the IntellyTrack, Goto (of course :)), Hand Controller Update and the Conrad Gears.

The electronics part was pretty easy.

Switching to the Conrad gears was a bit more tricky, that involved some drilling so the new gearbox screws aligned up with the original motor screws and by memory I also needed to take the small drive gear off the Conrad motors (they came with the gearboxes) and fit them to the Original HEQ5 motors. A bit of work but still not to bad. And for the more accurate control you get, well worth it.

I also regreased everything, probably something I wouldn't do again. I found it a fair bit of work and re-setting the tolerances between the worm drive and main gear to remove slack was a total pain in the butt, to put it politely.

There is also freeware software to run everything after you install the update. One of the best I've found (and use) is here:-

http://mcucontrol.dyndns.org/MCUControlPlus/

Click on the titles across the top to get the explanations of how to set it up and what it can do. It's pretty cool :thumbsup:

Mount Control DSLR Bulb Control Webcam AutoGuiding

Hope this helps.

Regards,

Markus

[wasyoungonce]

You really should use grease in the mount bearings...something like a light viscosity Lithium grease is OK.

Grease is designed to hold the lubricant in suspension and release it under load, heat and work.

Agreed that these bearings are not under great rotational loads but oil alone is not enough for adequate continuing lubrication.

[bojan]

Alex,
How did you polish the gears ? Perhaps the worm is easy(er), but the worm gear is certainly not [because all the teeth must have a proper (and same shape), in order not to introduce even higher PE].
Also, it seems that the replacement of the worm gear (there is a company in Germany that supply them) results in better performance. Their worm gera is different, the gears diameter match the worm diameter (this is not the case with original Synta's one, so the position alignment is much more critical).

[bojan]

Hi guys,
This:
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&rd=1&item=350060780829&ssPageName=STRK:MEWA:IT&ih=022
looks exactly like so called "Conrad gearbox" (from outside), used to replace the inferior original Synta gearbox.
The only problem is, I am not sure if it has required 1:100 reduction ratio, and seller does not have a clue...
Anybody here on the forum has any experience with these?

[OzRob]

This might be a it off topic but has anyone tried PEMPro with a EQ6 Pro mount?