Need Help =O Crayford Focusing Dilemma

[Keshdogga (Casey)]

Hey IIS,

I am having some strange and very scary trouble with my SW ED80's crayford focuser. Unless the focusing screw is tightened the focuser can slide out of the scope almost as it pleases. What caused it was when I was fillding around trying to get my gear setup when I tripped over my mount's leg and somehow I freaking dropped the ED80. It only fell about a foot, maybe a foot and a half, but it landed on a cement floor. There appears to be no external damage to the telescope at all. The other issue is that when I attempt to focus it kind of works fine then the mechanism seems like it gets caught on something making it alot harder to turn the focus nobs.

So to sum up I idiotically dropped the ED80 about a foot on concrete. Focusing tube is "loose" and can slide and focusing nobs become hard to turn in certain points. To be honest I'm freaking out. I can't believe I could do something so stupid as to drop the ED80 but I was hoping someone out there might have a solution? I'm completely stuck and I just wanna fix my baby =P

Many thanks,
Casey

[that_guy (Tony)]

try taking the focuser out and having a look see, there might be something stuck in the mechanism :/ good luck

[terrynz (Terence)]

Hi Casey,

the rack and pinion in the standard crayford focuser is a little crappy and I doubt it would survive that fall. Easy way to check is to unscrew the crayford (philips screw driver) and check the rack and the little bronze wheel is ok. If not measure the diameter of the crayford and order a GSO replacement from Andrews in Sydney. They're about $170 for the ED80 (96mm from memory) and a is money well spent. Personally I thinks its the best upgrade you could do to this scope.

cheers
Terry

[Keshdogga (Casey)]

Originally Posted by terrynz

Hi Casey,

the rack and pinion in the standard crayford focuser is a little crappy and I doubt it would survive that fall. Easy way to check is to unscrew the crayford (philips screw driver) and check the rack and the little bronze wheel is ok. If not measure the diameter of the crayford and order a GSO replacement from Andrews in Sydney. They're about $170 for the ED80 (96mm from memory) and a is money well spent. Personally I thinks its the best upgrade you could do to this scope.

cheers
Terry

Thanks Terry it's good to know that it already was a worth while upgrade. I would definately pay $170 for an upgraded one. Just a pity that I had to break it =S I took the focuser off the telescope and I just can't see any damage at all. There's clearly some metal on metal action but I just can't see it although I can hear it and feel it. I'm assuming I'd have to call Andrews to order? Just had a check on the website and I can't see any skywatcher GSO's haha.

And Tony I wish it was just something in the mechanism but there just appears to be nothing out of the ordinary inside the focuser Anyway It's not life threatening (as far as i know) but it would be nice fixed.

Thanks for the help =]
Casey

[[1ponders] (Paul)]

We'll have a look tonight Casey, plus I have an extra Orion Crayford here somewhere that will definitely be less that $170 and will get you out of trouble for a while

[mswhin63 (Malcolm)]

I wouild think with a fall it is bent out of alignment, Crayford doesn't have a Rack and Pinion instead uses bearing and pressure using a thumbscrew to add or take away the pressure from the bearings. If it is bent or out of alignment then when it reaches to the tolerance point it starts to scrape metal o metal. The thumbscrew has a teflon of fabric pressure stop check to see if this hasn't fallen off.