10 replies to this topic

[Hikescdnrckys]

I am a Dobsonian newbie (have used lots of SCTs but not many dobs. I have a new Skywatcher Synscan Flextube 200P Goto dobsonian. I have just set it up, but have not had it out yet for first light.

 

I have a quick question about the Optical Tube Locking Screw. When moving the tube manually I understand you loosen the screw until you have moved the scope to the new position and then tighten it so it doesn't move in altitude.

 

My question is should it also be loosened before moving the scope using the hand controller or when doing a goto, and then tightened once you are on the object, or does it need to be tight like a clutch before the goto so the motor will engage? 

 

Note this scope has the dual encoder, so you are supposed to be able to move the scope manually without losing the alignment. The manual doesn't really say to much about moving the scope manually.

 

Thanks.

[Hikescdnrckys]

I heard from support, and they just state it should be tight. It may just be a friction device to ensure the tube doesn't slip too much in altitude, given that it can be back heavy.

[RodgerDodger008]

I think you are talking about the altitude clutch if it is a goto flextube. Does the azimuth have the same "locking screw" ? Would be helpful if you can post a picture.

I have the 300p skywatcher flextube goto and if it is what I am thinking you loosen to use the scope manually but when using the hc and tracking it is tight, never over tighten just tight.

The scope comes with freedom find, when enabled you can loosen the clutches and use manually after allignment and then tighten again and the scope still knows where it is pointing.

Remember the freedom find needs to be turned on, of using it with wifi and the app dont use the hc and it is off by default. With the hc you need to make sure it is on. Personally i dont use freedom find, if you have wifi highlu recommend trying that, the app is great for visual.

Edited by RodgerDodger008, 24 May 2025 - 12:33 AM.

[mayhem13]

it need to be tight like a clutch before the goto so the motor will engage? 

Thanks.

You got it 

[Hikescdnrckys]

I think you are talking about the altitude clutch if it is a goto flextube. Does the azimuth have the same "locking screw" ? Would be helpful if you can post a picture.

I have the 300p skywatcher flextube goto and if it is what I am thinking you loosen to use the scope manually but when using the hc and tracking it is tight, never over tighten just tight.

The scope comes with freedom find, when enabled you can loosen the clutches and use manually after allignment and then tighten again and the scope still knows where it is pointing.

Remember the freedom find needs to be turned on, of using it with wifi and the app dont use the hc and it is off by default. With the hc you need to make sure it is on. Personally i dont use freedom find, if you have wifi highlu recommend trying that, the app is great for visual.

Yes. I am talking about the altitude axis. There are no external clutches on either axis, just one screw with a large black knob as per this picture.

 

Edited by Hikescdnrckys, 24 May 2025 - 06:34 PM.

[RodgerDodger008]

I dont see a picture but what you describe sounds like tge clutch in my manual 8 inch flextube so a bit confused.

[Hikescdnrckys]

I dont see a picture but what you describe sounds like tge clutch in my manual 8 inch flextube so a bit confused.

Sorry, just added the picture. Had typical issues with upload rotating the image.

[RodgerDodger008]

Sorry, just added the picture. Had typical issues with upload rotating the image.

That bolt mates the ota to the mount and should always be tight.

There is something funky looking with the altitude scale, if horizontal you should be in the 0 position and if pointing directly up it should be at 90. Possibly the image is inverted and looking at it at an angle.

The other thing with that bolt is when tight you should not be able to lift the ota off the mount. Make sure you have assembled it correctly.

Edited by RodgerDodger008, 24 May 2025 - 09:10 PM.

[RodgerDodger008]

I downloaded the photo and inverted it, not sure if your photo is inverted or not but when I inverted it the scale made more sense but then it also looked like the OTA was on backwards. 

 

What I can say is your version is the one without the manual clutch, as the HC sits where my clutch would be, this is not a issue btw. But as explained in my earlier post that that bolt goes through that side of the OTA and then screws into a hole in the mount to keep it connected and tight. When you want to lift the OTA off the mount you need to completely take that bolt out but the bolt itself has no purpose to do with the movement of the scope. Because there is no manual clutch on your model you simply move it up and down by hand against the friction. But Ideally just use the HC. 

 

When you put the OTA on again do move the scope to the perfect horizontal position and make sure the the scale does read zero. Let me know if any issues and if you post more images maybe I can help. Good luck

Edited by RodgerDodger008, 25 May 2025 - 01:59 AM.

[Hikescdnrckys]

I downloaded the photo and inverted it, not sure if your photo is inverted or not but when I inverted it the scale made more sense but then it also looked like the OTA was on backwards. 

 

What I can say is your version is the one without the manual clutch, as the HC sits where my clutch would be, this is not a issue btw. But as explained in my earlier post that that bolt goes through that side of the OTA and then screws into a hole in the mount to keep it connected and tight. When you want to lift the OTA off the mount you need to completely take that bolt out but the bolt itself has no purpose to do with the movement of the scope. Because there is no manual clutch on your model you simply move it up and down by hand against the friction. But Ideally just use the HC. 

 

When you put the OTA on again do move the scope to the perfect horizontal position and make sure the the scale does read zero. Let me know if any issues and if you post more images maybe I can help. Good luck

Thanks RodgerDodger008, that make perfect sense.

[dfepeman]

The locking screw is a bit confusing- you loosen it to remove the tube, but there is no definite “hey, it’s loose now” moment, as far as I can tell. I just keep loosening it and check occasionally. The tube can get a little stuck at times, so when you try to lift it out, it sometimes seems like you haven’t loosened it enough. I wish it was a more definitive mechanical device.