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10Micron counterweight question

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#1 Anding

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Posted 28 October 2020 - 05:56 PM

Hello, to manage shipping costs I should order the counterweights with the mount, so I need to estimate in advance what I need. There will be a 23kg 250mm cassegrain OTA with camera etc. (say 3kg max.). The mount is the GM2000 HPS combi. I am thinking 3 x 12kg. Does this sound about right or should I add a 1 x 6kg to be on the safe side?
Many thanks for your thoughts!

#2 TOMDEY

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Posted 28 October 2020 - 06:22 PM

It's always good to order more than you need. The strategy is called "Minimization of Maximum Regret". Having the small weight there, unused... is meh. Running out of weights in the middle of balancing... and the comet of the century staring you in the face... is Auugh!    Tom

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#3 Anding

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Posted 28 October 2020 - 08:27 PM

Good advice.  Thank you Tom!



#4 Raginar

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Posted 29 October 2020 - 01:14 PM

I'd add the extra weight.



#5 t-ara-fan

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Posted 29 October 2020 - 04:57 PM

Weights are best when pushed up against the scope end of the counterweight bar. This minimizes the moment of inertia.   So lots of weights close in are better than fewer weights further out.

 

https://www.astro-ph...ize-guiding.pdf

 

When I bought my AP mount, they told me the weights required for the OTAs that I owned. Can 10micron help you out?



#6 Raginar

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Posted 30 October 2020 - 01:28 PM

I don’t think 10u will give it to you. I’ve asked Ed Thomas for his opinion since I buy from him. I have 2 of each type and that works well for my max load.

#7 Anding

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Posted 30 October 2020 - 04:57 PM

I filled in the 10Micron enquiry form a few weeks ago and never received any response (to this and other questions), not even to my junk mail. I suspect I’ll have more weight than I need but I ordered 3x 12kg + 1x 6kg


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