Dovelm162 springs too short or assembled wrong?


M Hambrick
 

Hi Linwood

I used to mount my 180 EDT scope while the mount was in Park 3 until Roland suggested that having the mount in Park 2 makes it much much easier to mount the scope. He was right. The best way to do this for heavier scopes is to leave the rings attached to the dovetail plate and clamped to the saddle with the opening in the rings facing the south side. Then you place the scope into the rings. You may need a short step stool to facilitate doing this. Once the scope is sitting in the rings it will not fall out. You can then fine tune the position before clamping the rings. I think you can also leave the OTA attached to the rings and dovetail plate as you do and it is still easier to mount in Park 2. 

Mike


ap@CaptivePhotons.com
 

M Hambrick wrote:

 

  • Hi Linwood

    I used to mount my 180 EDT scope while the mount was in Park 3 until Roland suggested that having the mount in Park 2 makes it much much easier to mount the scope. He was right. The best way to do this for heavier scopes is to leave the rings attached to the dovetail plate and clamped to the saddle with the opening in the rings facing the south side. Then you place the scope into the rings. You may need a short step stool to facilitate doing this. Once the scope is sitting in the rings it will not fall out. You can then fine tune the position before clamping the rings. I think you can also leave the OTA attached to the rings and dovetail plate as you do and it is still easier to mount in Park 2. 

 

I appreciate the approach, but my heavier OTA is a C11 (with train about 40#) and has no rings, just a dovetail screwed to the OTA side.  Changing to mounting rings and a long solid Dovetail would add probably 15 pounds to the setup (based on Bisque’s rings).  I see where it’s possible with my TV NP101is, but it would be pretty tedious compared to just sitting it into the saddle and tightening (plus the 101 is really light in comparison).

 

Because I set up and tear down every (clear) night, every little bit of time saved helps.  For that reason I also try to leave the imaging train attached when I remove the OTA, so the rotation is still set for the next night (assuming same target; manual rotation only for me).

 

---

 

So this relatively little spring issue spurred more interest than I expect and I am now curious.  It sounds like the manufacture is unchanged, but also people indicate they don’t have the issue.  Is it that the issue is moot, or it doesn’t exist?


Specifically do some of you have the 16” dovetail, which when set up with knobs pointing to the sky, if you loosen the knobs the clamp’s spring stays engaged and holding it against the knob all the way until the clamp clears the saddle’s gap completely? And if you jiggle or press back, it pops back open, clearing the gap.

 

On mine if I do that the spring stops holding it with the clamp extending into the saddle’s gap by about 1/8”, enough to keep a dovetail from dropping in.  It’s really about that close, it is not much.

 

But some of you have versions where that is not true?   Or just your use makes it moot (e.g. knobs down it would not matter)?

 

 

 

 

 


Tom Blahovici
 

I'm the OP and this is exactly the case with mine.
Just for people reading this, if you are doing this with the clams down you will not have an issue, however you should try it with the clamps up. It is vastly easier and more secure.
I start by placing the saddle horizontal with the clamps up. You can then take the complete telescope, rings and dovetail and just position it so the lower groove engages the groove on the saddle. This is already more secure than the other way around, with the clamps down since there is no groove on that side. You can then with one hand just push on the whole scope until it contacts the saddle plate and then the other hand can just tighten the clamps.
Of course if the clamps don't open enough then they get in the way.
Tom


Woody Schlom
 

Knobs up or sideways not a problem.  All my springs and clamps still work as they always have – and should.  Well, I think so.  Haven’t used that mount in a couple of years now.

 

Woody

 

From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of ap@...
Sent: Friday, September 17, 2021 6:36 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Dovelm162 springs too short or assembled wrong?

 

M Hambrick wrote:

 

Ø  Hi Linwood

I used to mount my 180 EDT scope while the mount was in Park 3 until Roland suggested that having the mount in Park 2 makes it much much easier to mount the scope. He was right. The best way to do this for heavier scopes is to leave the rings attached to the dovetail plate and clamped to the saddle with the opening in the rings facing the south side. Then you place the scope into the rings. You may need a short step stool to facilitate doing this. Once the scope is sitting in the rings it will not fall out. You can then fine tune the position before clamping the rings. I think you can also leave the OTA attached to the rings and dovetail plate as you do and it is still easier to mount in Park 2. 

 

I appreciate the approach, but my heavier OTA is a C11 (with train about 40#) and has no rings, just a dovetail screwed to the OTA side.  Changing to mounting rings and a long solid Dovetail would add probably 15 pounds to the setup (based on Bisque’s rings).  I see where it’s possible with my TV NP101is, but it would be pretty tedious compared to just sitting it into the saddle and tightening (plus the 101 is really light in comparison).

 

Because I set up and tear down every (clear) night, every little bit of time saved helps.  For that reason I also try to leave the imaging train attached when I remove the OTA, so the rotation is still set for the next night (assuming same target; manual rotation only for me).

 

---

 

So this relatively little spring issue spurred more interest than I expect and I am now curious.  It sounds like the manufacture is unchanged, but also people indicate they don’t have the issue.  Is it that the issue is moot, or it doesn’t exist?


Specifically do some of you have the 16” dovetail, which when set up with knobs pointing to the sky, if you loosen the knobs the clamp’s spring stays engaged and holding it against the knob all the way until the clamp clears the saddle’s gap completely? And if you jiggle or press back, it pops back open, clearing the gap.

 

On mine if I do that the spring stops holding it with the clamp extending into the saddle’s gap by about 1/8”, enough to keep a dovetail from dropping in.  It’s really about that close, it is not much.

 

But some of you have versions where that is not true?   Or just your use makes it moot (e.g. knobs down it would not matter)?

 

 

 

 

 


M Hambrick
 

Hi Linwood

You raise a good point about your C14 not having rings. That changes things quite a bit. As to your question:

Specifically do some of you have the 16” dovetail, which when set up with knobs pointing to the sky, if you loosen the knobs the clamp’s spring stays engaged and holding it against the knob all the way until the clamp clears the saddle’s gap completely? And if you jiggle or press back, it pops back open, clearing the gap.

My clamps exhibit essentially the same behavior as you describe for yours. When I loosen the knobs, the OEM spring is completely uncompressed before the edges of clamps are completely out of the dovetail gap. This has not been a problem for me however because I am not trying to manage a heavy load at the same time I am opening the clamps. For my 180 EDT I mount my SBD16 dovetail plate with rings attached to the DOVELM162 before attaching the scope. For my Stowaway and NP101 scopes I mount the SBD12 with the rings and scope already attached to the DOVELM162. In either case, if the clamps are in the way I can just push them back with one hand while holding onto scope / rings with the other.

Per my earlier post, I tried out some longer springs and they did work as far as pushing the clamps back, but they were a little bit too long and I was worried that they would eject the clamp and knob, so put the original springs back in.

I am still wondering if you would not have an easier time installing your C14 into the dovetail plate from Park 2 instead of Park 3.

Like you, I set up and take down my setup every session. I am always on the lookout for ways to speed up the process.

Mike


skester@...
 

I have the same issue described here but with the DOVEDV10 plate I received with my 1100GTO in April of this year.  The springs run out of travel before the clamps have fully retracted.  It's not a big deal for me as I mount the scope rings first and simply push the clamps all the way back prior to doing so.  But I wanted AP to be aware the same issue is occurring with the 10" dovetail plate.


Worsel
 

See this video for an approach to works for me, even for the few times that I have had to take the OTA off in an observatory.  14.5" IDK on an 1100 GT.  I did build a table that sits at the right height when the OTA is rotated down.  I did not think a stool was substantial enough.

https://www.youtube.com/watch?v=IwVg1M6bURI&t=167s

The video is a bit over the top and a little jumpy, but the concept is clear.

Bryan