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Orion XT6 focuser (question for user/former user)

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#1 moynihan

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Posted 16 April 2013 - 10:18 AM

I have a question about the focuser on the Orion XT6 OTA i recently acquired. The focuser is rather stiff. If anyone knows how to adjust it, it would be appreciated, PM me if ya want.... :question:

#2 Ed D

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Posted 16 April 2013 - 02:11 PM

The first thing I would try is loosening the two screws that secure the plate that holds the focus knobs and shaft. If more than snug it could cause the hard turning of the knobs. Also, you may consider cleaning out whatever lube may be in it (Synta goop?) and relubing with a light grease only on the rack, the pinion, and the points where the shaft rides on the focuser body. The focuser tube rides on teflon strips inside the body, so no need to lube the tube surface.

Ed D

#3 kfiscus

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Posted 16 April 2013 - 04:40 PM

Check the larger knurled set screw on the top/back of the body.

#4 moynihan

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Posted 16 April 2013 - 07:20 PM

The first thing I would try is loosening the two screws that secure the plate that holds the focus knobs and shaft. If more than snug it could cause the hard turning of the knobs. Also, you may consider cleaning out whatever lube may be in it (Synta goop?) and relubing with a light grease only on the rack, the pinion, and the points where the shaft rides on the focuser body. The focuser tube rides on teflon strips inside the body, so no need to lube the tube surface.

Ed D


loosening those 2 screws (actually, 4 on mine), seems to have eased it. Thanks.

#5 Jon Isaacs

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Posted 16 April 2013 - 07:52 PM

I have a question about the focuser on the Orion XT6 OTA i recently acquired. The focuser is rather stiff. If anyone knows how to adjust it, it would be appreciated, PM me if ya want.... :question:


In my experience, the Synta rack and pinion focusers all can be significantly improved so that they are smooth, free and tight.. This is how it do it:

Reworking a Synta Rack and Pinion Focuser

#6 Bob Riggs

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Posted 20 April 2013 - 11:14 AM

Good thread Moynahan, and thank you Jon for the link to the older thread.

Clear skies all...

#7 Scanning4Comets

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Posted 20 April 2013 - 11:59 AM

In my experience, the Synta rack and pinion focusers all can be significantly improved so that they are smooth, free and tight.. This is how it do it:

Reworking a Synta Rack and Pinion Focuser


IMO, this is true, however, IMO, you'd be much better off getting a completely new focuser like I did. I removed that thing which my friends joked about having to need a pair of vice grips to operate. :lol: The difference is like night and day since I got rid of it and got myself a real crayford focuser. Another good option is going to a 2 speed for more precise focusing when needed.

#8 precaud

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Posted 20 April 2013 - 06:52 PM

I removed that thing which my friends joked about having to need a pair of vice grips to operate.


Nothing like peer pressure to inflate/deflate one's sense of value of something... :lol:

After a simple cleanup, re-lube, adjustment of the two tension screws, and putting on one larger knob, mine is very smooth and slop-free. I haven't felt any need to upgrade it.

#9 Jon Isaacs

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Posted 20 April 2013 - 09:38 PM

In my experience, the Synta rack and pinion focusers all can be significantly improved so that they are smooth, free and tight.. This is how it do it:

Reworking a Synta Rack and Pinion Focuser


IMO, this is true, however, IMO, you'd be much better off getting a completely new focuser like I did. I removed that thing which my friends joked about having to need a pair of vice grips to operate. :lol: The difference is like night and day since I got rid of it and got myself a real crayford focuser. Another good option is going to a 2 speed for more precise focusing when needed.


Well...

Did you first rework you focuser with the Teflon and all so you can make a real comparison? If your focuser was so stiff that your friends joked about needing vice grips, it needed help. To me, for a $300 telescope, it doesn't really make sense to spend $150 to upgrade the focuser. One could have purchased an 8 inch F/6 with a two speed Crayford and had money in the bank. A couple of more points:

- It's worth noting that the really good focusers are rack and pinion. Astro-Physics, Takahashi, TEC, TeleVue, they're all rack and pinion. The rework suggested doesn't turn the focuser into a high end focuser but it will be tight, smooth and relatively light. And it will be more positive than a Crayford.

- At F/8, the depth of focus is sufficient that a 2 speed focuser is unnecessary.

Jon






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