C80ED Focuser.

[Merlin]

Does anyone know how to remove the heavy casting/focuser from a C80ED, so that it can be replaced with a Crayford focuser?

[Deneb]

You should be able to unscrew it counterclockwise, or try using a rubber strap wrench..

Nadeem.

[Dave Smith]

You should be able to unscrew it counterclockwise, or try using a rubber strap wrench..

Nadeem.

Agreed. I have just taken mine off with a rubber strap wrench as a test before ordering an upgrade focuser. They can be quite tight.

Dave

[Deneb]

Or Glued on, as I have heard !

[Merlin]

Thanks, Chaps, I tried a while ago to unscrew the tube as you've suggested, but to no avail. I'll keep trying and hope for the best.

I wish they hadn't designed the 'scope with such a heavy casting in the first place.

[Rusty Strings]

I replaced mine with a crayford. The original one unscrewed and had no sign of glue.

[johninderby]

Some of the focusers can be very, very difficult to remove indeed. The thread on the OTA is often poorly made and hence the focuser can be jammed in place. It's a bit of a lottery I'm afraid. Some just unscrew by hand and some just don't want to come off.

John

[pjspur]

Just a word of warning (although I am sure noone would been quite as stupid as I was). Be very careful not to hold the tube with the lens facing down at any point during or after removal of the focuser. There was an amazing amount of metal scrappings floating about in there that came off the focuser screw thread when it was removed. I tipped it 'lens down' accidentally while holding it and quite a bit got on the inside of the lens which took quite some sorting out! I also had one of the baffles floating around in there as well!

Paul.

[johninderby]

Just a word of warning (although I am sure noone would been quite as stupid as I was). Be very careful not to hold the tube with the lens facing down at any point during or after removal of the focuser. There was an amazing amount of metal scrappings floating about in there that came off the focuser screw thread when it was removed. I tipped it 'lens down' accidentally while holding it and quite a bit got on the inside of the lens which took quite some sorting out! I also had one of the baffles floating around in there as well!

Paul.

If possible unscrew the objective cell and put it safely out of the way first.

John

[Mr Bond]

Interesting. Does this also apply to the C100ED too?

[Odd Thomas]

Interesting. Does this also apply to the C100ED too?

Yes it does. I was lucky, mine unscrewed no probs. Mrs held the tube (!) and I unscrewed the focuser assembly, it was fairly tight but no signs of anything on the threads.

[Mr Bond]

Thanks. :-)

[Seme]

Mine unscrewed a bit stiff but not to bad.

Where is the best uk site to grab a new focuser for a c80ed i have the adaptor?

[Deneb]

you could approach telescope service in germany to buy a focuser, just remember , you wont need to pay taxes due to being in the eu or buy yourself a moonlight.

Nadeem.