Another counterweight query...

[RT65CB-SWL]

Do you think I need to add another couterweight to my Vixen GP if I dual-mount with any of the 'scopes as per my signature? (the included weight is 1.8kgs)  ...and if "Yes!" what weight?

The ETX105 & C6 are quite heavy now that I use SCT accessories*, (and I may add a camera). They will be mounted as a 'side-by-side' configuration.

 

* 2" Altair Astro star diagonal or Baader Crayford focuser.

[Bukko]

Hello, Phillip,

It has been a long time since I dual-mounted some scopes, so this will be from memory... Hopefully, someone with more experience will step in and correct me, where required...

The counterweights. Normally, I have found you need about the same weight in counterweights as the optical rig. But the Vixens place most of the mount weight on the counterweight side, so you can probably get away with less.

Balancing... Tricky...

I balances a 10" Meade SCT with an 80mm Equinox, complete with ep's, cameras, etc.  on an NEQ6. As the mount rotates on axis, any imbalance throws the load off. As you change the accessories on each scope, it changes the balance also. With the dual saddle, it throws the load off center adding to the difficulty.

The best technique I worked out was to balance everything off the mount first. Attaching a scope to its dovetail, I would load it as required and move it on the dovetail until I found the balance point. A little masking take marked the spot. I would do the same with the second one, then mount them both onto the dual saddle and work out the center of balance on that.

Locating this point in the middle of the mount would get it very close. Rotating on the axis would confirm if I was "near enough" and make a slight adjustment, if I needed to.

Good luck and I hope this helps.

 

Gordon.

[RT65CB-SWL]

Hi Gordon, and thank you.

I have been watching a few YouTube videos about balancing dual-mount 'side-by-side' setups.

Should I add a camera at a later date, I presume the Meridean Flip is adding to problems? 

So much easier with the Giro! 

[Bukko]

Every time I made a material change to the payload, it would upset the balance.

Adding weights to other parts of the load helped, but it was an ongoing struggle. The NEQ6 backlash was troublesome, especially around a flip. I needed to re-align again afterwards.

I used the second scope as a tracking scope mostly. In the end I sold on the Meade OTA and got a big newt. At the same time invested in an OAG and a single scope on each mount.  I guess I took the easy route out, but spending a lot of time making stuff work is not productive, especially where we get so little scope time anyway...

Good luck with your set up.

Gordon.

[kirkster501]

I have always found side-by-side balancing very tricky, such so that I am about to abandon it and sell my side-by-side bar and live with the fact that you sometimes need to swap the scope on the mount.  By definition, you use such a setup to give you different options in terms of scope/camera/FoV etc.  Consequently, those different "options" then make it difficult to get the balance right since they are by nature different apertures and weights (unless identical setup with two similar rigs).  Not impossible, but in my experience very tricky.

[kirkster501]

On 10/27/2017 at 21:05, Bukko said:

<snip>

I guess I took the easy route out, but spending a lot of time making stuff work is not productive, especially where we get so little scope time anyway...

<snip>

I could not have said it better myself.

[sloz1664]

I found balancing scopes "side by side" tricky also. I could balance correctly to start the imaging session but soon as it performed a meridian flip the whole rig was way, way off balance. I eventually abandoned this idea and now run two rigs on top of each other. The balancing is far easier and with a bit of fiddling with weight distribution the balance is correct on either side of the pier after a meridian flip.

Steve

 

[sonof007]

May I just make an enquiry. All your cables appear to go into Hub of some sort.  What is this or is it part of the mount? Thanks.

[sloz1664]

Yes I have two Startech industrial 12 volt powered 7 port usb hubs mounted to the pilar. Never had a single issue with the hubs. Usb leads, power and other issues, but not the hubs.

https://www.startech.com/uk/Cards-Adapters/USB-2/Hub/Mountable-Rugged-Industrial-7-Port-USB-Hub~ST7200USBM

Steve