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[RobbW]

Alright, I'm going to use this thread to document my attempt to Hypertune(TM) my Celestron CG5 Advanced Series Go-To mount. With the warmer weather approaching, I want to do what I can to make sure my equipment is in tip-top shape for the new observing season. I purchased my Celestron C8-CF XLT with CG5-ASGT mount off of Craigslist back in September last year. It has performed wonderfully for me since then. However, I have had a few issues with the mount here and there, and it is an older used system. So, I figured a mount makeover was in order.

I scoured the 'net and found tons of info on tuning up your mount. A lot of that info related to a company called Deep Sky Products and their Hypertune(TM) service. They offer a service whereby you can ship your mount to them and they will perform their magic to pimp it out and make it be the best that it can be. Unfortunately, that service comes with a relatively hefty price. Thankfully, they also offer a DIY package that provides all the same parts they would use and instructions on how to perform the Hypertune service in the comfort of your own home. I went with the DIY option as I am cheap and have a passable mechanical aptitude.

I have not yet received the official DIY Hypertune package yet. It is en route. However, Ed Thomas at DSP emailed me the exploded diagrams for my mount ahead of receiving the package. Also, I found other instructions online for disassembling and cleaning my mount. So I got started taking it apart and getting it cleaned up in anticipation of receiving the Hypertune goods.

I set up operations in my dining room, as it hardly gets used and there is a big table to lay out all my tools and parts. I tossed a couple of furniture covers on the table top to protect it and started laying out my tools and instructions.

My daughter, Maddie, was there to manage and supervise. She unleashed her creativity upon some of my hex keys and an unfortunate Styrofoam participant.





Below is my CG5 mount in its pre-op state, and then separated into the RA and DEC axes.





I kept careful track of all the small parts during disassembly. I numbered the pics in the instructions and put the screws and other small parts in corresponding numbered cups.



Here is the completely disassembled DEC axis laid out according to the exploded diagram provided by Deep Space Products. Following that are a couple closeups of some of the internal parts.







Next is the disassembled RA axis with exploded diagram and then a gratuitous closeup.





Here is an edge-on shot of the entire disassembled mount.



After getting everything broken down, it was bath time! One of the first things you need to do before performing the nitty gritty Hypertune service is to get rid of all the old grimy lubricant. So I enlisted the help of a heavy-duty citrus degreaser purchased at a local big-box home improvement store. I sprayed down all the parts with the degreaser and let them soak for a few minutes.





After the degreaser had some time to dissolve most of the old lube, everyone jumped into a nice, warm, soapy bath for a good ol' scrub-down.





Well folks, that's as far as I can go for now. Everything is nice and sparkling clean. However, I have to wait until the Hypertune package gets here before I can go any farther. Once it arrives, I will continue on and update this thread with lots more pictures.

Until then, Clear Skies!

[Chicago Astronomer Joe]

Robb,

What an ambitious project.

Excellent that you are documenting it in photos. My C11 disassembly/cleaning has become legendary and a go-to procedure.

What are you going to use for a lubricant? I heard Dow Corning Vacuum lube is great stuff. I wait for the next chapter.

One other question?

Is that the wife's table cloth?


Read more: astronomer.proboards.com/index.cgi?action=display&board=StarParty&thread=3077&page=1#ixzz1HA8dl3AA

[RobbW]

I believe Super Lube is included in the Hypertune kit. No, the wife would kill me if I used her tablecloth. That's an old ratty furniture throw.

[Paulie pchris00]

Nice report and good luck with the rest!

Btw, I think Maddie had just a little more fun than you did!

[mojocvh]

Great report on the start of your project, please return to keep all us "discontinued" CG5'ers in the frame....

cheers

Andy frea Perthshire

[RobbW]

And so the journey continues!

After disassembly and cleaning, it was time for the nitty gritty: sanding and polishing! The process involves taking every part that comes in moving contact with any other part and sanding it down to remove any imperfections, burs, spars, blemishes, or anything else that isn't as smooth as Jesus' baby butt! First you sand with a 320 grit sandpaper to get rid of all the rough spots. Then you move up to a 600 grit sandpaper to really smooth it out. Then, once every muscle in your hands and fingers is aching with pain, you move up to a metal polish, which is the equivalent of about 5000 grit (quick aside for those unaware... the higher the grit number, the finer or smoother the sanding).

Here is one of the axis gears:



I'm sanding and smoothing both the inside and outside of the gear.



Don't get confused if it looks like I'm doing all this great work with only one hand. I had to use one of my hands to take the photo. I didn't take the time to set up some fancy self-photo contraption to capture myself in the action (a la Chicago Joe's famous narratives).

The next two photos show the before and after of the RA axis shaft. It might not look totally shiny and perfect in the after photo, but you don't have to polish every square centimeter of your mount. You only have to worry about those areas that come into contact with other metal parts.





After sanding and polishing all the contact spots, it was time to pull out the lube... SuperLube that is!!! This is a higher-end lube that was included with the Hypertune kit. It is synthetic and contains PTFE, some sort of micro powder that makes it uber-slick. You just apply it to all the parts that come into contact with each other and rub it all over nice and greasy like!





After the lube party is over and it finally comes time for reassembly, some of the original parts get replaced with better parts that come in the Hypertune kit. First off are all the plastic washers that are installed between every single moving part in the mount. These plastic washers are crappy to the Nth degree. They were all gnarled and scarred and burred and cut up. Nice, new, super-slick Teflon washers came with the kit. The Teflon washers are the white, clean ones atop the others in this next photo.



Next came the replacement of the bearings in the worm gear assemblies. The DIY kit came with new, super ceramic bearings that fit onto each end of the worm gear. You can see the old crappy bearings with the exploded view of the worm gear assembly, and then the new bearings in the following photo.





At this point, I've nearly got everything put back together:



The only things left are the axis motors and final reassembly.





In all, the entire process took me between 3-4 days. Now, I know you may be thinking that's an awfully long time. However, I only got to work on this project for a couple hours each night after my daughter went to bed. In total, it probably took about 6-8 hours. But this was the first time I attempted a Hypertune, plus I'm usually kind of anal/OCD about this kind of stuff anyway.

After everything was put back together, it was time for testing. During this phase, I discovered two things: 1) I'm an imbecile, and 2) I'm an imbecile with tendencies towards complete and utter stupidity. I got everything back together and started testing to see how my hard work paid off. It didn't!

When slewing, the motors sounded like a wounded and dying moose, whatever that sounds like. I imagine that sounds very similar to a cow on death's doorstep. Anyway, the motor whirring noise was very inconsistent and seemed to stutter a bit. Also, I was having trouble with the mount even completing a simple star alignment. Each time I tried to align, the motors would slew real fast towards the first alignment star and then suddenly stop and then start moving in a very slow rate (faster than sidereal rate, though). It would keep slewing at this slow rate forever until I manually stopped it. This happened over and over. I was becoming increasingly worried that I seriously flubbed something up during the operation.

After much research on the net, I had a couple ideas on what was causing the problems. The most likely was an insufficient power supply. I was using a 12V AC adapter to operate my mount. It turns out that the Celestron CG5 Go-To mount is exceptionally finicky about its power supply. It requires 12VAC and 1.5 - 2 Amps. My power supply was only spitting out 400mA! That's not good! The other problem was that I had meshed the axis motors too tightly with the worm gears during final assembly. This was causing severe binding.

I went to Radio Shack and bought a brand new 12VAC 2.5A regulated power adapter. I also pulled off the covers on my motors and readjusted them to a better mesh. Now, finally, everything is working perfectly after ample testing. Now, thing only thing I have to wait for is warmer, clearer weather in which to take out my newly tuned mount!!!

[Chicago Astronomer Joe]

Robb,

I didn't take the time to set up some fancy self-photo contraption to capture myself in the action (a la Chicago Joe's famous narratives)

I am pleased my efforts are recognized.... ;D


This is a very cool project that you have undertaken.

Indeed scary, as things drop and roll away too easily...and as you experienced, the factor of human error that may creep into things.

It's got to be better now than even when brand new. I'm a great promoter of improvements and modifications. Have you noticed a smoother operation post project?

[RobbW]

I haven't really had a chance to test, Joe. I only have the mount set up on its tripod in my dining room. I haven't put the OTA on yet. I've only been running the mount unloaded. So far, it seems extremely smooth, especially after I got a proper power adapter. I'll know more once I can take it out, put a tube on it, and test out the tracking.

[patrickm]

Wow!! What a project, amigo!

My only question is how many parts you had left over at the end?

Can't wait to check it out.

[wwpierre]

Thanks, Robb. I am tuning my CG5 now, and this thread is invaluable. I am also documenting the process photographically. I have a "new type" mount that I motorized after acquisition. It has ball bearings as well, which seem to be in excellent shape.

One difference is that I found the citrus de-greaser pretty useless, and opted for paint thinner, followed by the de-greaser, followed by a good wash in water.

[wwpierre]

I finished my tune-up. I took photos all the way through that might be helpful to anyone else performing this worthwhile maintenance. I didn't use the Hypertune Kit, but I did polish all the faying parts with 1000 grit wet-or-dry emery paper. (as best I could), and replaced the lubricant with good quality lithium grease.

The mount works very smoothly now.

The photos are at: www.photobucket.com/cg5tuneup

[mojocvh]

You're sure right about this plastic washers as well.......

[scottmason]

Out in the field, I've been using a 12 volt, 8 amp hour battery. The AC wall adapter I charge it with reads Output: 12V 500mA
Not sure if the output for the battery is the same as the charger but if it is, could that explain the issues I've been having with slewing?

Another weird thing that happens... At the WOW Observers weekend Star Party it was going nuts, slewing to the exact opposite direction in the sky I wanted it to, often the DEC motors not working at all. I had a veteran astronomer who was very familiar with Celestron come try to help out but he was baffled. We checked everything to make sure it was properly aligned and it didn't solve anything. The only thing he could come up with is that the dec port was loose.

I just today replaced the dec board and power board with new ones, and still the same issue. I tried Deneb as a calibration star, which was NE in the sky (although it was daytime, this was a test in my home). The mount pointed west, instead of East.

When I got the mount, the Dec Port was upside-down compared to the way the rest of the ports plug in. Therefore that's the way I reinstalled it. Is it possible that's the issue and I need to install it right side-up?

[mojocvh]

forget previous suggestion LOL.

90% of CG5 weirdness is down to power supplies.

ATB

Mo.

[scottmason]

I had a hell of a time trying to fit the chip back into the covers after the replacement, so I'm a bit apprehensive going back to stage 1. I may as well try but I feel I've already caused a good amount of wear and tear just replacing the dec board and power board. Lots of screws going in too tight, stripping etc.

Is it possible that plugging directly into the wall would bring the wrong amount of juice?

[mojocvh]

Did it work out in the field...........

[scottmason]

I finally got it wired back correctly. The only issue is my gears getting "stuck". Sometimes when slewing with the up key, it won't budge until I hear a loud whir and then it jumps back into action, moving quite a bit with the jump.

Maybe I need a hypertune?