Meade Help Required

[AstroJunk (Jonathan)]

Leave it on the mount and horizontal, erring on leaning back toward the focusser. As soon as you have removed the 3 bolts, you can move the main mirror by pulling the mechanism back and forth. Just slip it sideways and the focus mechanism will come off the pin and can be removed.

Just make sure that the primary mirror isn't facing downwards when you finally set it free!

Originally Posted by thunderchildobs

When I remove the focuser, which is the best / safest / easiest way. Can I remove the focuser while the scope is still on the mount, (keeping the tube horizontal) or do I need to dismount the tube from the mount?

Thanks Brendan

[thunderchildobs]

Another question. Does the mirror lock need to be engaged or disengaged when removing the focuser?

[AstroJunk (Jonathan)]

Either. BTW Having the mirror lock unit in position actually prevents the mirror slipping off the shaft if you have the tube pointing downwards and it is unlocked.

I prefer it unlocked so I can get a feel for how freely the mirror is moving.

[thunderchildobs]

I have removed the focuser to see what it looks like.
The focuser and the bar it attaches looks ok, straight and everything seems firm and there is nothing rattling in the tube. (1st and 2nd images)

What I did notice when a reinstalled the focuser for the first time, the focus lock jammed and turning the focuser was very stiff.

I removed the focuser and tried again. As I was tightening the focuser screws , I turned the focuser lock and could see the focus knob turning!! It seems like some part of the focuser is touching the focus lock tooth plate.
Have I incorrectly reinstalled the focuser? At this time I haven't removed the focuser lock.

Looking through scope it seems that the primary mirror is not square (3rd image)

Looking down the tube there seems to 4 screws (4th and 5th image) that come from tube and I cannot tell what they do. They appear to be touching mirror or at least the mirror cell. What is the purpose of these screws?

Thanks

[Merlin66 (Ken)]

Ahhhh
You may have found the problem/ issue!
Those two screws you show in photo#4 should NOT be there!!
It looks like the screws, used to attach a finder etc are toooooo long and probably interfere with the mirror travel.
They should be unscrewed to at least stop any interference with the mirror.

[casstony]

Was the tube originally in a fork? Looks like a deforked model and the screws used to fill the holes are too long.

[thunderchildobs]

Originally Posted by Merlin66

Ahhhh
You may have found the problem/ issue!
Those two screws you show in photo#4 should NOT be there!!
It looks like the screws, used to attach a finder etc are toooooo long and probably interfere with the mirror travel.
They should be unscrewed to at least stop any interference with the mirror.

Originally Posted by casstony

Was the tube originally in a fork? Looks like a deforked model and the screws used to fill the holes are too long.

Thanks. Those screws are definitely in the position where the forks attach to the tube. They have always been there since I bought the scope new in 2010!! The focuser had always been easier to turn in some places and harder in others. I always thought it was just a focuser thing. The scope has always been a imaging scope and I used a meade zero shift focuser. No need to touch the focuser knob once set.

I removed the screws and guess what, the focuser is now nice and smooth.
I can now also see a noticeable movement in the mirror when the focuser is turned fully in and out.

I can now get to focus. This has solved my original problem.

However, I now have a collimation problem. I am going to start a new thread for this.

Thanks to everyone who offered help.

Brendan

[Greg Bock (Greg Bock)]

Great thread guys, ..co-operative, helpful, and informative.
Now i must have a look down inside my 14" tube to see what's there..just out of curiosity.