EQ2 Fine Declination Control Problem

[tgdavies]

Hi,

I'm a complete beginner and have just bought a second hand Skywatcher 90mm Maksutov-Cassegrain, to get my feet wet (living in Sydney's Inner West, where the light pollution is awful I wanted something I can take away on holiday reasonably easily).

So far I have just set it up for terrestrial viewing to get accustomed to it.

I have found one problem , which is that the fine adjustment for the declination seems to only work in one direction. I'm not sure whether all these adjustments work the same way, but mine has a lead screw which pushes against a tab on the locked part of the Dec axis to turn it, but turning the control the other way can't pull the tab back. There is a cylinder which screws into the other end of the adjustment mechanism, aligned with the lead screw, which looks as though it may have a spring loaded plunger to push against the tab as the lead screw is withdrawn, but if so, the plunger has seized.

Is my guess about this correct? Any advice on freeing it?

(please correct my terminology too!)

Thanks,
Tom

[rogerco]

:welcome:Might be best if you try and take a photograph or two of the area and screws you are referring to :screwy:

[tgdavies]

Here's a picture of the mount:

https://www.evernote.com/shard/s1/sh/d79e8618-363b-4c0d-b51e-c28a951353db/1e6873fd0b22448bac83df5c057c6fb1

And the component which might be a spring loaded plunger:
https://www.evernote.com/shard/s1/sh/673abb94-6819-474e-bcba-a2382fcc26ce/b6f31ef8e6ee6720b77df64cfe8cb184

[brian nordstrom]

:thumbsup:you are right , just undo the Dec mechanisim and un-seize , I had one like it years ago and the spring had broken into 3 pieces , Bunnings had one that was perfect and it is still good today after all these years .
Also check the balance , these are great little mounts when balanced properly :) I have a 1972 Meade 60mm f15 under mine .

Brian.

[tgdavies]

Thanks Brian.

I have a counterweight, and instructions for balancing, but I don't really understand why balancing is important?

[brian nordstrom]

:Dwithout good balancing an EQ mount is basically useless, the scope becomes a dead weight :shrug: AND any scope OTA wont like crashing around , it will get out or alignment and give horrible images , look after your scope .
Sorry to say , take your time getting it right and you will be rewarded with great observing .

BRIAN.

[tgdavies]

A bit of penetrating oil and some flats filed on the end of the plunger allowed me to free it -- it had corroded stuck at full compression. The spring was OK.

It's very satisfying to fix something instead of chucking/replacing it!

[brian nordstrom]

:thumbsup: Great news Tom and yes its a good feeling when something turns out ok after a bit of tinkering .
Your Mac will be a good match for the EQ2 , any chance of a photo ?

Brian.