Synscan issue

[PeterEde]

Hi All
It's been some years since my last confession/visit.
I sort of lost interest when my now 6 yr old son arrived.
In that time I upgraded my mount to an EQ35M PRo and had trouble aligning so put it away for a few years out of frustration.

Well I thought I'd give it another go.

Now I think I found why I had troubles.

Everything seems to work ok except slewing during alignment. It stops before reaching the target. I also lose the power light on the controller but the hand controller still has power. I hope that makes sense?

Anyway I thought I'd open the black box and look for anything obvious. I am electronics repair trained. All looked ok except for L3 on the board.

It looks to be soldered on the outside of the coil only to the ground plane through hole to the back.

While the inside end of the coil looks to be solder free and can be clearly seen to wiggle on the other side. It looks very free of solder.

Without knowing how this coil behaves in the circuit I have not as yet tried to solder it to the board.

If anyone has had isses with this please let me know.
I'd love to get back into Astrophotography.

Thanks
Peter

[PeterEde]

I'm thinking maybe my drive gears need fresh lube.
What can I buy local to do this job.
My mount has sat for many years unused.

Thanks

Peter

[Leo.G]

Personally I use the white Lithium grease for gears, it doesn't melt like moly grease (Molybdenum disulfide) and doesn't freeze. It comes in spray cans and is easy to apply and thickens on contact with the air (I'm assuming as it comes out in a liquid spray).
In a cloudy nights thread it recommends against white Lithium grease, apparently it dries out easily but Superlube which is a synthetic grease is recommended.


https://thetoolgroup.com.au/collections/superlube


White Lithium isn't an issue for me because I grease the gears semi regularly.
Internally in my mount I use Nulon Extreme (Supercheap Auto) which is a red lithium grease with PTFE added for extra slip


There are marketed greases available from astronomy supplies too:


https://www.testar.com.au/products/grease-for-mount


The most important part of greasing the gears is remove the old stuff first. Depending on the level of strip down I'm doing/prepared to do, I find electrical contact cleaner spray (I keep it for electronics) softens the old stuff as does petrol, what I use depends on whether I'm doing it in the yard or in the house. Some (many) greases harden with age and also trap a lot of dust and grime, removal of the old grease and cleaning is usually the best option, a tooth brush and plenty of rags/paper towel works, wipe the grease off the toothbrush on the paper towel, rinse and repeat.


This is a tractor forum, hence the 5 gallons. Methylated spirits will also break the grease down slowly.
There's also recommendations of oven cleaner in certain forums. Oven cleaner damages certain alloys so I'd recommend against trying it out on an expensive mount. I tried it out on an expensive motorbike engine myself, luckily I had a spare engine in good condition.......
Live and learn, SOMETIMES........


SOme older threads with recommendatios:


https://www.iceinspace.com.au/forum/showthread.php?t=167869&highlight=greasing+mount+gears

https://www.iceinspace.com.au/forum/showthread.php?t=117905&highlight=greasing+mount+gears


Good luck Peter!

[PeterEde]

Thanks Leo

I bought a NGLI2 PTFE based grease at Jaycar.
But it pretty much melts. Next time I pass by Supercheap I'll get a tube of the nulon

Thanks

Peter

[Leo.G]

The melting shocks me a little Peter, it's marketed as high pressure grease.
The Nulon grease with the PTFE isn't so much for the drive gears though I believe I probably used it when I hyper-tuned and re-engineered my EQ5 PRO mount. I can't afford better but had the head machined to accept a tapered roller bearing on the RA axis (4mm deeper and friend with large engineering shop) instead of the lesser quality standard roller bearing. Considering the EQ5 PRO is much cheaper than the HEQ5 I wouldn't expect the same build quality but I now have a much better quality mount, along with the thrust bearing on the bottom of the same axis, the standard thing is more like tinfoil and very hard to obtain.
There's also a major difference in the internal worm gear, I believe the HEQ5 and EQ6 (HEQ, NEQ) have the brass worm gear which is more like an internal drum with nicks machined in, mine has alloy. That is where I wanted the PTFE grease, all internal. Plus the shim spacers weren't PTFE, they were PET plastic. They are all now PTFE (though I destroyed an unobtainable leg retainer (needle retainer) on a very expensive Rotring (older $200 plus compass)) from my drawing set, I can probably machine a new part on the lathe and milling machine one day but it's so small and my eyes don't do tiny any more. Compass being used to basically scribe through the 0.5mm PTFE sheet to make the appropriate sized shims. My mount is very smooth and last time I bothered aligning it correctly (by luck me thinks) it performed flawlessly for a much lesser mount.


I'm often wary of Jaycar products, often cheap Chinese imports. They used to be great, not so much now.





The operating range is good with the Nulon Extreme, not the cheapest grease but I do a lot of mechanical based stuff and I bought the 450 Gram tub
https://en.wikipedia.org/wiki/NLGI_consistency_number


This doesn't seem to mention the temperature ranges of the varying NLGI grades, the nulon extreme runs -9C to 150C temperature range.
Again, a great internal grease, won't hurt on the gears but there will be better, slightly thicker greases with high melting temperature.
I believe I used Moly grease once and it melted on a hot night and made quite the mess. The PTFE probably isn't required for the drive work though,
Don't forget to check the meshing of the drive gears, too tight and you will have issues, there needs to be minimal backlash and also, if you want to go that far check neither set of end bearings the worm gear sits in have seized, that too will cause a lot of drag and issues.


Good luck and if I can be of any help don't hesiotate to fire off a PM. I don't know near as much as a lot of people here but I probably seem to come in a little more regularly andI'm more than happy to try and assist if I can

[Startrek]

Personally I’d look at the control box first before worrying about replacing possible sticky grease.
I’ve had my EQ6-R pro mount carrying an 8” Newt for 6 years now and never replaced the grease , and it’s permanently outside with just a cover over it , still as quiet as it’s ever been. All I’ve done is adjust the tension on both axis , adjust the drive belts and adjust the worm gear backlash to guide better.
If your mount is well balanced and slews freely using the handcontroller with no grinding or unusual sounds in both directions of axis as far as you can go before hitting the tripod legs and both axis move freely when the clutch is released then maybe look at replacing that suspect control box. I’d guess trying to hand solder that induction coil might do more damage on that cheap pc board.
Maybe get a price off Adriano at Testar for a replacement board or send him an email with your issue ( he used to work for Skywatcher Australia)
I had an recent issue ( electronics) with my 12” Goto dob and although both Adriano and I couldn’t pin point the exact issue , he got my rig up and running again after me stuffing around for months and months.

You can always do a hypertune later as a re grease requires you to pull the whole mount apart bearings and all to do it thoroughly. Just throwing a bit of new grease on the motor gears is probably not going to make a huge difference if the mount is less than 4 or 5 years old and has been stored in a dry place.

Cheers
Martin