Equatorial Mount EQ-35 Pro failing guide on DEC

[Tracy]

I've been having issues with the EQ-35 Pro with a high DEC rate in Stellarmate OS.
I watched a couple of videos on how to adjust the DEC portion of the mount, and have the scope well balanced and removed as much of the backlash as I could using the small allen screw and confirmed that the gears rotate easily and that when the "head" is moved to the left and right there is minimal movement when locked.
Now the issue I am having is that when trying to get it to guide, when it reaches the DEC in portion, it times out.

Instead of using Stellarmate guiding, should I simply attach the ST4 cable from the guide scope to the hand controller of the EQ-35 Pro and not mess with any of the Stellarmate guide functions? Will the SynScan controller handle all the guiding, or is it necessary to use the StellarMate function and then use the via function of Stellarmate?

I'm SO confused and frustrated with this mount right now.

 

[Tracy]

I've gone in with Stellarmate and had it use the VIA Synscan and now am getting some decent numbers... still have to get the RA balanced a little better apparently.

 

[OhNo]

You are now understanding the reason long term APers always say "Spend your money on the mount"!

 

[Tracy]

Yep... looking at either an iOptron CEM40 or a Celestron CGX if I have to buy myself. Would really like a iOptron CEM70, and that may still be in the cards as a "gift".

 

[Tracy]

Pretty sure I still have to do some more fine tuning on the balancing... but so far it's been holding pretty steady at these readings...
Not great, but right now I want consistency as much as anything... once I can get that I can work more on the balance...but what do you really expect from a $900 mount setup? It probably is fine for live viewing and using a smaller scope, but my rig is probably pushing it, as a light wind this morning REALLY sent the RA/DEC into fits.

 

[Tracy]

I'm really beginning to think this mount is an absolute piece of crap. Even with my little Apertura 72mm rigged out for DSO it's having issues... and that is WELL within it's weight limits.
The biggest issue is the "sticktion" that the DEC and RA axis has. With this smaller telescope... you can pretty much move the mount anywhere but the extreme ends of the Vixen mount or even the weights for the RA and you get NO balance issues the stiction is so bad.

I think later today it's on the schedule to strip this mount down to it's core, use some cleaner and get off ALL that wonderful high-priced Chinese grease and then re-grease everything and then adjust even more for the backlash issues this mount has.

This is the BEST I've been able to do tonight... and I've had to reset/rebalance the system several times after only a few minutes of running sine total RMS would jump up around 4.5. The DEC axis has been giving me fits.

Meanwhile.. the EQ6-R Pro has been rocking along with this being the highest it's had.

I did find that my QHY 5-II color guide/planetary camera really sucked with the 32mm guide scope the Apertura 72mm came with. Right now I'm using my ASI585MC with it.. and it seems to be doing decent.

 

[OhNo]

To hell with the Graph image. Let's see the total RMS. The graph can be manipulated and guiding improved by the manipulation..

Looks like it is time to make another video. Hint: the sky here won't clear until the weekend and then the bottom end of the thermometer is going to fall out!

I am beginning to discover why long term APers fade away on forums...

 

[Tracy]

Let's see the total RMS. The graph can be manipulated and guiding improved by the manipulation..

Same as what is shown on those graphs in the numbers above the chart... with the exception that over time, the TRMS of the EQ-35 Pro climbs to around 6'ish (as by the live tracking in the Stellarmate OS software where it shows the corrections applied and whatnot) and the chart does also follow that increase in the DEC RMS increase. SNR is decent and doesn't change as the DEC results slowly increase. In fact that image the TRMS stayed around 1.3-1.5 for about 30 minutes, then climbed up to 5.8 before I shut it all down and started over again, where it stayed around 1.3'ish for 20 to 30 minutes then began climbing again. Don't concentrate on the graph... but on the numbers. Those are not based upon that graph - that simply gives you a baseline of what was seen and as you said, it can be manipulated.. but the numbers above it are live numbers.

I'm pretty sure it's a binding situation as the grease is that high quality Chinese grease and is over 4 years old now. The last time I had the mount apart it was more tacky than slick. The grease used on the EQ35/EQ35 Pro has been commented on for a while as being junk.... same as on many of the Skywatcher style mounts. The stiction is so bad that I have to REALLY have the mount out of balance before it will even move... and that's on RA or DEC axis, but at certain points it will show minute out of balance. It's just not across the board. This mount is also known for having a LOT of DEC backlash as it ships from factory.. which can be somewhat alleviated, but is trial and error with it.
I'm in the process of stripping the EQ35 Pro down and removing all the old grease (leaving the Krytox on the RA/DEC gears themselves) and putting new grease on the internal bearing surfaces.

 

[Tracy]

Well, after doing a total cleaning of the DEC axis parts (gears and bushings) and then re-greasing them (Mobil 1 synthetic on the bushings, Krytox on the gears) it seems that the DEC axis numbers are a tad bit better.

Mounts  Cleaning and greasing your EQ-35 Pro

If you are like me and have one of the older EQ-35 Pro's (mine is a rebadged William Optics) then you are probably familiar with the issues with the DEC axis stiction/tightness. My total RMS was never below 1.5 at the BEST of times, and I even followed the guide on "tuning" it that I found out...

• Tracy
• February 5, 2023
• Category: Guides

Now, the next complaint I have is having to use RJ-11->USB conversions. Luckily the newer EQ-35 Pro's appear to have a USB A plug on their base control box that the hand controller attaches to, allowing direct connection similar to what the EQ6-R Pro does. I've got an email in to Skywatcher to see what the cost to get an updated controller is... but if it's more than a few hundred dollars, I'll simply put that money to the side towards a more capable mount.

 

[Tracy]

Has anyone upgraded their EQ-35 Pro wit the Astro-Gadget EQStarProEQM35 kit?
Once nice thing I see is it upgrades the brass gears to actual belts... but does it realistically give you that much more, seeing as how the mount itself has bushings instead of the more reliable bearings and the actual brass gears are higher tooth count than the normal EQ-3 mount?