Re: Jerky RA drive motion
On Thu, Jul 8, 2021 at 10:56 AM, Michael Herman wrote:
Oldham coupler
I'll start there, thanks
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Re: Jerky RA drive motion
Hi gang,
This sounds like a case of loose setscrew(s) on one (or both) end(s) of the Oldham coupler.? These setscrews are very small.... usually taking an 0.050 inch Allen wrench.??
In the past, I've drilled and tapped these to use 4-40 thread setscrews.? The 4-40 are slightly larger but more easily driven by the next larger Allen wrench size.
Try looking there first for the trouble.
Best, Michael
Yes the clutch was tight.
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Re: Jerky RA drive motion
Yes the clutch was tight.
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Re: Jerky RA drive motion
I'm sure you checked this, but was the clutch tight? Maybe it needs cleaning??
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Re: Jerky RA drive motion
This was on my workbench with no equipment or weight to balance,
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Re: Jerky RA drive motion
To clarify further, this was during the Goto and the SkyFi was not yet connected.
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Re: Jerky RA drive motion
a couple things come to mind in addition to the advice you got
one is good balance - and make sure the weight has an eastern bias
another is it could be taking up backlash in RA (especially if it's unbalanced as per above)
how accurate is the goto?
No - this was noticed before proceeding to connect the SkyFi device.
This was observed during the GoTo bright star.
-- Brian?
Brian Valente portfolio
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Re: Jerky RA drive motion
No - this was noticed before proceeding to connect the SkyFi device.
This was observed during the GoTo bright star.
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Re: Jerky RA drive motion
Hi Tom
Are you saying this is a problem when you use SkyFi or just when you do any sort of slewing i.e., the hand controller?
if you aren't sure, it would be good to confirm how well this works with the hand controller without any software involvement
I'm looking for advice on where to start trouble shooting my RA drive issue. I have a vintage G11 mount that I updated with the Gemini II GoTo system about a year ago. This past week I set it up on my workbench to do an initial setup with the SkyFi III wireless Controller. The SkyFi III Quick Start Guide indicates connecting to the telescope after an alignment.
This is where I noticed my PROBELM. When slewing to a bright star on the Eastern side, I could see the slew motion stop while continuing to hear the servo driving and the continue to slew and hesitate the motion and slew again. So to characterize this; with the RA drive servo continuously operating, the actual saddle motion stops for a second or two then starts again and continues in this fashion until the servo stops.
I called the Losmandy and was directed to start checking the drive train components first for proper engagement which I think is very good advice. I am reaching out to see if anyone else has had a similar issue and what the solution was.
Thanks,
Tom
-- Brian?
Brian Valente portfolio
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I'm looking for advice on where to start trouble shooting my RA drive issue. I have a vintage G11 mount that I updated with the Gemini II GoTo system about a year ago. This past week I set it up on my workbench to do an initial setup with the SkyFi III wireless Controller. The SkyFi III Quick Start Guide indicates connecting to the telescope after an alignment.
This is where I noticed my PROBELM. When slewing to a bright star on the Eastern side, I could see the slew motion stop while continuing to hear the servo driving and the continue to slew and hesitate the motion and slew again. So to characterize this; with the RA drive servo continuously operating, the actual saddle motion stops for a second or two then starts again and continues in this fashion until the servo stops.
I called the Losmandy and was directed to start checking the drive train components first for proper engagement which I think is very good advice. I am reaching out to see if anyone else has had a similar issue and what the solution was.
Thanks,
Tom
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Re: Adding grease to existing greased worm and wheel
Hi Greg,
The CRC brake and caliper grease has added anticorrosion chemicals so the MolyDisulphide does not (through some chemical reaction) react and corrode the brass worm.? I'm not sure if your older grease has this so I'd say: get the new grease.??
I'm usually very experimental, but in this case the $100 brass worm value far exceeds the cost of a jar of the CRC brake and caliper grease.
All the best, Michael
On Thu, Jul 8, 2021, 8:01 AM Gregory Latiak < glatiak@...> wrote: Michael,
I have a can of Molykote G that I used to use for brake jobs on my performance german sedan... back from the days it was made by Dow-corning. Its taken me decades to make much of a dent in the little can (bought it back in the 1970s). Might this be similar to the CRC you mention??
greg latiak
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Re: Adding grease to existing greased worm and wheel
Michael,
I have a can of Molykote G that I used to use for brake jobs on my performance german sedan... back from the days it was made by Dow-corning. Its taken me decades to make much of a dent in the little can (bought it back in the 1970s). Might this be similar to the CRC you mention??
greg latiak
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Re: Firecapture autoguide with Gemini 1 ?
I must question my own statement....
"In both cases you will need a special narrow 4 pin phone jack to get your laptop PC to talk to the Serial Port (marked "RS232" on the Gemini-1) to your laptop.? "
Maybe you only need the Serial port cable if you choose not to use the RJ11 cable.? ?
I always use the Serial port connection and ASCOM and Gemini.net.? I've never tried autoguiding without that already in place.??
Have fun, Michael
On Thu, Jul 8, 2021, 3:49 AM Michael Herman via <mherman346= [email protected]> wrote: Hi David,
You have 2 options... here is how to use either way.? Most people use the "pulse guide" method by not using the RJ11 cable at all (option 2 below).?
1. Use a cable that came with your ASI camera to connect the RJ11 autoguider input port on the Gemini-1 to the RJ11 autoguider output port on the ASI camera.? If you choose to use this cable, then (in PHD2) you select the camera as "ASI" and select the mount type as "on camera" meaning on the autoguide camera.? ?
2.? Do not use this cable at all.??If you choose to use no cable, then (in PHD2) you select the camera as "ASI" and select the mount type as "ASCOM" and this will pop up.the mount "chooser" and you select the mount as "Gemini.net".? This option seems to me to work equally well as the wired option....with one fewer cable to worry about snagging.??
_______
In both cases you will need a special narrow 4 pin phone jack to get your laptop PC to talk to the Serial Port (marked "RS232" on the Gemini-1) to your laptop.??
For this purpose I make up a coiled serial port cable...has a 9-pin DB-9 connector to this special 4 pin phone jack for the Gemini-1.??
That cable plugs into a reliable ATEN UC232A USB to serial port device. The ATEN unit appears in your laptop as a Serial Port, and the ASCOM Gemini.net will usually automatically find the already powered on Gemini-1 from the serial port response.? See photo of this cable.??
If you choose to make your own cable, the Gemini-1 manual, attached, gives specs on these serial and autoguider? connections.??
See the attached PDF also for a step by step How-To.??
Have fun, Michael
So I¡¯m confused on the type of cable. (I have a USB3 cable from my ASI 174 to my laptop) The Gemini 1 controller has a RJ11 port for Autoguide. Do I need an RJ11 to usb to go from that port to my laptop??
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Re: Firecapture autoguide with Gemini 1 ?
Hi David,
You have 2 options... here is how to use either way.? Most people use the "pulse guide" method by not using the RJ11 cable at all (option 2 below).?
1. Use a cable that came with your ASI camera to connect the RJ11 autoguider input port on the Gemini-1 to the RJ11 autoguider output port on the ASI camera.? If you choose to use this cable, then (in PHD2) you select the camera as "ASI" and select the mount type as "on camera" meaning on the autoguide camera.? ?
2.? Do not use this cable at all.??If you choose to use no cable, then (in PHD2) you select the camera as "ASI" and select the mount type as "ASCOM" and this will pop up.the mount "chooser" and you select the mount as "Gemini.net".? This option seems to me to work equally well as the wired option....with one fewer cable to worry about snagging.??
_______
In both cases you will need a special narrow 4 pin phone jack to get your laptop PC to talk to the Serial Port (marked "RS232" on the Gemini-1) to your laptop.??
For this purpose I make up a coiled serial port cable...has a 9-pin DB-9 connector to this special 4 pin phone jack for the Gemini-1.??
That cable plugs into a reliable ATEN UC232A USB to serial port device. The ATEN unit appears in your laptop as a Serial Port, and the ASCOM Gemini.net will usually automatically find the already powered on Gemini-1 from the serial port response.? See photo of this cable.??
If you choose to make your own cable, the Gemini-1 manual, attached, gives specs on these serial and autoguider? connections.??
See the attached PDF also for a step by step How-To.??
Have fun, Michael
So I¡¯m confused on the type of cable. (I have a USB3 cable from my ASI 174 to my laptop) The Gemini 1 controller has a RJ11 port for Autoguide. Do I need an RJ11 to usb to go from that port to my laptop??
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Re: Firecapture autoguide with Gemini 1 ?
So I¡¯m confused on the type of cable. (I have a USB3 cable from my ASI 174 to my laptop) The Gemini 1 controller has a RJ11 port for Autoguide. Do I need an RJ11 to usb to go from that port to my laptop??
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Re: Adding grease to existing greased worm and wheel
I heard about Nye Fluorocarbon Gel 868H, but it seems very costly.?
CRC grease looks like a very good option - cheap and no mixing.
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Re: Adding grease to existing greased worm and wheel
Hi Jim,
There are several sources of backlash.? I'd list them as:. 1. Worm side movement along it's axis 2. Worm gap to it's ring gear 3. Other drive gears or Oldham coupler looseness.
#2 is helped by lower worm to ring gear friction, because if that were frictionless you could push the wirm further into its ring gear.??
The other way to eliminate #2 on RA is to hang a weight from a cord wrapped so the weight hangs to the East of the RA axis.?
#1 is eliminated by allowing the far bearing to slide in it's cylinder, and putting a spring (R4 size Belleville spring washer) behind it to push the worm toward the gearbox end.??
#3 is minimized by tightening up on the drive parts.?
In all of this effort you must beware of creating tight spots in the drive.
On Wed, Jul 7, 2021 at 02:12 PM, Derek C Breit wrote:
And a mixture of 3:1 Lubriplate 105 and Nye Fluorocarbon Gel 868H for the worms
Does this help with backlash?
------------------------
Jim W
Phoenix, AZ. USA
Losmandy GM811G, NINA 1.11, ASI2600MC Pro, Sky-Watcher Scopes
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Re: Adding grease to existing greased worm and wheel
On Wed, Jul 7, 2021 at 02:12 PM, Derek C Breit wrote:
And a mixture of 3:1 Lubriplate 105 and Nye Fluorocarbon Gel 868H for the worms
Does this help with backlash? ------------------------ Jim W Phoenix, AZ. USA Losmandy GM811G, NINA 1.11, ASI2600MC Pro, Sky-Watcher Scopes
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Re: Adding grease to existing greased worm and wheel
Yep..
And a mixture of 3:1 Lubriplate 105 and Nye Fluorocarbon Gel 868H for the
worms..
?
Derek
?
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From: [email protected] [mailto:[email protected]] On Behalf Of Alexander Varakin
Sent: Wednesday, July 07, 2021
1:48 PM
To: [email protected]
Subject: Re: [Losmandy_users_io]
Adding grease to existing greased worm and wheel
?
I use a toothbrush with detergent and hot water to remove old grease.
Of course, this requires disassembly of the mount, but it is super easy to do
this with Losmandy mounts.
What people are using for the rest of the mount?
I use Lubriplate 105, which is recommended by a couple of premium mount makers.
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Re: Adding grease to existing greased worm and wheel
I use a toothbrush with detergent and hot water to remove old grease. Of course, this requires disassembly of the mount, but it is super easy to do this with Losmandy mounts.
What people are using for the rest of the mount?
I use Lubriplate 105, which is recommended by a couple of premium mount makers.
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Michael Herman
Jamie Amendolagine