Quote:
Originally Posted by Astromelb
Interesting reading guys.
1. The buyer asked me as seller to assist with the motors, when they didn't work. I told him what to do and they then worked. Astronomy 101 stuff. why was this even asked ?
2. He then asked questions about gearing, and again I assisted with guidance. Then I heard nothing further. I repeat then heard nothing further ?
Then I get a couple of calls from people I know on IIS asking whether this guy knows enough to run this unit. I cannot answer this, ask him.
This thread is the usual tangents going off all over the place without being intimately involved. With one side of the story and totally inadequate actual detail.
Great stuff guys - shooting first without asking any questions 
Seriously guys, this stuff is premier gear and needs care, and attention to detail, to get operational. I get a little of this from time to time when people buy gear and due to the learning curve of this level of gear have issues.
Sad, but don't bag people when you aren't involved. Poor behaviour from some of you. Particularly a PM received today from someone that knows who he is, and doesn't know me whatsoever, his language was appalling, get a set of manners mate
To the others that rang me to support, thanks guys, appreciate your caring  |
Quote:
Originally Posted by baileys2611
For clarity, I want to show the facts here - I don't want to make assertions about a person, their experience or other qualities as that is not the issue here.
The advert did lead me to understand the condition was good enough to assemble the mount, perform a few tweaks and then use it without maintenance.
Here and here are videos of the DEC operating without load. On testing the mount, when I used it to slew this sounded like metal grinding on metal. This may have 'disappeared' under full load, but in my experience if an issue is present, putting a full load on what I suspect to be a failing component would make me negligent and risk the equipment and the mount.
On manually testing the worm, it did not move smoothly but bumped and halted regularly - this was while disengaged from both the motor and the DEC gear.
When I removed the worm block and inspected the bearings, I found them worn and in one case missing a raceway entirely and with dried grease. Here is the photo of those bearings, here is a photo of the replacement bearings and here is a comparison shot.
I have since replaced those bearing, re-greased the DEC gear and worm block, re-seated it and adjusted it under load (evidenced here). Here is what it sounds like now. There are no bumps when I manually test the worm drive and no grinding noises when it slews (please excuse the frogs, it's night time).
This leads me to believe that the issue was worn bearings and that this was present when I took ownership of the mount.
As to periodic error - when I get a chance and have correctly polar aligned the mount, I will post the results here. It's cloudy tonight and I'm going away with my family for the weekend, but I'm eager to get this working to specification so will persist. |
Perfect reply Simon, and thank you for not sinking to the level of personal retorts.
There was a mechanical issue with the mount as received. You amply demonstrated your mechanical aptitude that was called into question in not only diagnosing it but potentially fixing it.
