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Old 25-04-2021, 02:56 PM
Zuts
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A question about counterweights

Hi,

I just added another counterweight to my setup to reach proper balance.

The way I understand it counterweights are not included in the recommended weight maximum so it should be fine. Is this true or is it too heavy for an azeq6 plus Esprit 120 plus 4 to 5kg of camera, guide scope, AsiAir pro, micro powerbox, cables, flattener.

Thanks for any replies.
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  #2  
Old 25-04-2021, 03:31 PM
Startrek (Martin)
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Your AZEQ6 mount has a max payload of 22Kg ( recommended Astro payload 16kg )
My EQ6-R mount has a max payload of 20kg ( recommended Astro payload 15kg )
I have 3 x 5.1kg counterweights on my mount ( it only came with 2 x 5.1kg counterweights )
So the answer to your question is 3 x 5.1kg are fine for your AZEQ6 mount

Due to the laws of physics with “moment of inertia” in balancing weight (mass) on an axis , the opposing forces of torque are minimised if the weights are closer to the centre of axis or pivot point
I would slide your counterweights together as one single static weight and then slide them as close to the mount as possible whilst keeping the mount balanced plus a slight adjustment for “East Heavy”
I have my 3 x 5.1kg counterweights locked up together and pushed up the counterweight shaft as close as possible to the mount. I had to buy a counterweight extension shaft as my existing shaft was 40mm too short and adding another counterweight was counterproductive
There’s a lot of conjecture about this principle , it works fine for me with tracking and guiding but I just do it anyway as most Astro sites , YouTube clips , video and magazines you see this configuration time and time again , I’ve rarely seen the counterweights spaced apart until I saw your photo
My recommendation......
Cheers
Martin
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Old 25-04-2021, 04:30 PM
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Merlin66 (Ken)
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I use the NEQ6pro for the C11, spectrograph and four camera etc.
It needs five c'weights
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Old 25-04-2021, 04:35 PM
Zuts
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Quote:
Originally Posted by Startrek View Post
Your AZEQ6 mount has a max payload of 22Kg ( recommended Astro payload 16kg )
My EQ6-R mount has a max payload of 20kg ( recommended Astro payload 15kg )
I have 3 x 5.1kg counterweights on my mount ( it only came with 2 x 5.1kg counterweights )
So the answer to your question is 3 x 5.1kg are fine for your AZEQ6 mount

Due to the laws of physics with “moment of inertia” in balancing weight (mass) on an axis , the opposing forces of torque are minimised if the weights are closer to the centre of axis or pivot point
I would slide your counterweights together as one single static weight and then slide them as close to the mount as possible whilst keeping the mount balanced plus a slight adjustment for “East Heavy”
I have my 3 x 5.1kg counterweights locked up together and pushed up the counterweight shaft as close as possible to the mount. I had to buy a counterweight extension shaft as my existing shaft was 40mm too short and adding another counterweight was counterproductive
There’s a lot of conjecture about this principle , it works fine for me with tracking and guiding but I just do it anyway as most Astro sites , YouTube clips , video and magazines you see this configuration time and time again , I’ve rarely seen the counterweights spaced apart until I saw your photo
My recommendation......
Cheers
Martin
Thanks Martin.

I will try with the weights together. I can't use the counterweight extension bar as I lost it and it is next to impossible to get a replacement at the moment.

Adrian at Teststar Manly recommends against their use for a number of reasons, rigidity and length of moment arm.
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Old 25-04-2021, 04:37 PM
Zuts
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Quote:
Originally Posted by Merlin66 View Post
I use the NEQ6pro for the C11, spectrograph and four camera etc.
It needs five c'weights

After looking at that my three counterweights seem rather wimpish

Also, you seem to experience no issues with the extension bar.
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Old 25-04-2021, 04:46 PM
Startrek (Martin)
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Quote:
Originally Posted by Zuts View Post
Thanks Martin.

I will try with the weights together. I can't use the counterweight extension bar as I lost it and it is next to impossible to get a replacement at the moment.

Adrian at Teststar Manly recommends against their use for a number of reasons, rigidity and length of moment arm.
Adrian is right , but if you only need an extra 30m to 50mm of shaft it won’t have to much adverse affect.

I only needed an extra 40mm of shaft to keep the weights together and my mounts performs very well
I was going to get a guy I know to make me up a 120mm extension shaft including chrome plating etc... but it was going to be triple the cost of buying
a Skywatcher 190mm extension bar , so I bought the Skywatcher part
Cheers
Martin
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Old 25-04-2021, 04:49 PM
Zuts
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Quote:
Originally Posted by Startrek View Post
Adrian is right , but if you only need an extra 30m to 50mm of shaft it won’t have to much adverse affect.

I only needed an extra 40mm of shaft to keep the weights together and my mounts performs very well
I was going to get a guy I know to make me up a 120mm extension shaft including chrome plating etc... but it was going to be triple the cost of buying
a Skywatcher 190mm extension bar , so I bought the Skywatcher part
Cheers
Martin
It seems balanced with all the weights together, so no need of an extension bar for me
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Old 25-04-2021, 05:06 PM
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Merlin66 (Ken)
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No extension bar used....just the original c’weight bar.
Works well for me, no issues.
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Old 25-04-2021, 05:29 PM
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Zuts

I actually use the extension bar as I can't get it to balance perfectly. Only need 10kg to balance my 15kg set up due to the fulcrum effect. My tracking usually sits between .5 and .7
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Old 04-05-2021, 06:51 AM
Zuts
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Thanks Ken and Kuz,

I have now used the 3 weights on both my Esprit 120 & Edge 9.25 and can get good balance without the extension, which is lucky as I don't have one.

Cheers
Paul
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Old 17-05-2021, 01:23 PM
Craig_
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Hmmm this has me wondering whether I should add a third CW to my EQ6-R for the Esprit 120...
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Old 18-05-2021, 07:03 AM
Startrek (Martin)
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Originally Posted by Craig_ View Post
Hmmm this has me wondering whether I should add a third CW to my EQ6-R for the Esprit 120...
Depends on whether your mount has various size counterweights as accessories
Skywatcher mounts usually have 5.1kg, 3kg and 1.8 kg

You can have too much CW as well and not enough shaft. I wouldn’t recommend having your counterweights pushed hard against to mount end either as you need a bit of play , they do flex a couple of mm

My 2 cents ......
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Old 18-05-2021, 09:28 AM
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Quote:
Originally Posted by Startrek View Post
Depends on whether your mount has various size counterweights as accessories
Skywatcher mounts usually have 5.1kg, 3kg and 1.8 kg

You can have too much CW as well and not enough shaft. I wouldn’t recommend having your counterweights pushed hard against to mount end either as you need a bit of play , they do flex a couple of mm

My 2 cents ......
Right now I use 2x 5.1kg counterweights on the EQ6-R with both pushed right to the end of the (non-extended) shaft. To balance East Heavy I can slide up one counterweight about 1cm for imaging on the western side of the meridian, and to balance east heavy for the eastern side of the meridian I need to use the extension shaft.

Total payload is approx 13kg. So 3x 5.1kg CWs pushed quite far up the shaft may work better from a moment arm perspective? Hard to say without a weight to try with
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Old 18-05-2021, 11:44 AM
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Merlin66 (Ken)
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I needed an additional 2Kg counterweight with a 18mm bore. Not all SW c'weights fit all mounts..
I ended up with a couple of 1Kg rubberised lifting weights, they have a 25mm bore.
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