Jump to content
  • Join the online East Midlands astronomy club today!

    With active forums, two dark sites and a knowledgeable membership, East Midlands Stargazers has something for everyone.

EQ5 Slipping?


Perkil8r

Recommended Posts

Tried taking a few pics the other night with my DSLR attatched, just as a quick toe in the water really. Got a half decent pic of Jupiter and all 4 moons, a bit over exposed, but not bad and in good focus. I then just pointed to a random patch of sky in orion to see what I could get.

The result of a single 10 second exposure @ 1600 ISO.

I assume I should not really have star trails anything like this at that kind of exposure time? I seem to be able to move the scope with relative ease with the clutch as tight as I can get it. I've had it apart once a few weeks back and realised I could adjust it so did so which made a bit of a difference. My theory is that the brass (?) part of the clutch seemed to be greased, is this how it should be, or has the previous owner gone ott with grease? The grease on the worm drive etc is a pale yellow and quite thick whereas the grease on the clutch is more like Lithium grease and a dark grey.....

I didn't have the MD on at the time as I assumed a 10 sec exposure wouldn't need it. Any thoughts, tips etc greatly welcomed.... may as well get it sorted whilst the clouds are about ;) (buying an EQ6 or HEQ5 are off limits at the minute.)

Link to comment
Share on other sites

Guest Kheldar

Put the motor drives on, I suspect it's star trails.

However if you can move the axis easily with the clutch on, then I suspect you haven't adjusted the worm engagement correctly when you put it back together?

Link to comment
Share on other sites

I didn't take the worm drive apart, I just removed the clutch to see what the story was with it etc. I only know about the grease on the worm drive from when I took the puck off. I am of course assuming here that the same grease has been used on the dec as the RA

Link to comment
Share on other sites

Guest Kheldar

Did you remove the worm carrier (the whole thing containing the worm) from the mount, or remove the large brass gear fully from the mount?

Did you adjust the worm carrier grub screws at all?

If you did so, it needs adjusting. What you are describing is "play" in the mount and is a sign it needs to be adjusted.

I can't comment on your mount specifically, but on the HEQ5 you release the three cap headed countersunk bolts slightly and adjust the worm carrier adjustment grub screws on either end.

The brass gears should be lubricated (either with stock Chinese crud or lithium grease) as should the worms themselves.

Link to comment
Share on other sites

Oh no, nothing like that..... I took the brass piece out that "locks" the axis, the clutch. I've just had it apart again, beyond the brass piece there is a small plastic spacer that pushes against the axis. (I'm probably not making much sense, sorry) Anyway, the plastic bit has a feeling of teflon to it, so I took the decision to remove it, clean all the grease off it (since the teflon is in it's self slippy enough against the metal) and cleaned some of the grease off the part it pushes against. I've put it back together and now it takes a lot more effort to rotate the axis while the clutch is in the locked position, which is what I was after. The action is still silky smooth when unlocked, so as far as I can tell I might have cured some of the issue.

Of course, it will help to get the scope, weights and camera on and see it in action, but it certainly seems to be better than it was and it does make sense. I'm of the opinion that it doesn't need any lubrication on that particular part, and it probably didn't have any there when new. The last chap to have it told me he had stripped, cleaned and greased everything up, and whilst he seemed pretty clued up on astronomy, I have the feeling he maybe wasn't the most mechanically minded person given some of the small issues I found with it. And to be honest, he was, how shall we put it..... erm.... a bit of a "space cadett" if you catch my drift, observing on the grass shall we say. (and I don't mean the lawn)

Link to comment
Share on other sites

There's no play in the gears or the actual mount. It was just that the clutch was slipping without much force. I'll give it a go now and see how she goes, but might need to clean it up a bit more yet. I'm pretty much convinced there shouldn't be any grease on that "ring" so to speak.

Link to comment
Share on other sites

Guest Kheldar

My DEC had no grease on the gear, the RA did : I put a light coating on both the gears before I reassembled and haven't had any issue with it so far.

Granted I'm on my third night of trying to adjust the RA axis play, it's not going well :) DEC was a doddle!

Glad you've got it about sorted though :D

Link to comment
Share on other sites

The "ring" the clutch presses on should be grease free.

As I suspected, thanks ;) I'll set to work on it again and also the dec too since that's very slippy too. I think he got carried away with the grease :rolleyes:

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.