DIY counterweight for my C8 SCT

[Knighty2112]

After pricing up the Baader dovetail bar levelling counterweight available from FLO for the princely sum of £74 (plus P &P) I decided to cobble together my own system to attach to the dovetail on my C8 SCT with things not currently been utilised for anything, so screwed together two spare dovetails, and then fitted my old saddles from my Skytee II Mount which I had replaced with better ones, which can be moved or taken off if required. This gave me exactly the weight I required so I could balance things all up nicely with my Canon camera attached to the rear end of my C8 SCT. So a good way to save nearly £80 me thinks. Won’t be as noticible either with the dewshield in place either!   

https://www.firstlightoptics.com/counterweights/baader-dovetail-bar-levelling-counterweight.html

[Stu]

If it works, and the kit is not doing anything else, why not?

I made a counterweight out of bits and pieces to go under the front of my frac which balances Binoviewers very well

[Knighty2112]

18 minutes ago, Stu said:

If it works, and the kit is not doing anything else, why not?

I made a counterweight out of bits and pieces to go under the front of my frac which balances Binoviewers very well

Exactly! It was stuff that I wouldn’t have been able to sell anyway I doubt (tried selling the larger black dovetail before, but no one wanted it), so may get some use out of them. Works a treat too, and doesn’t look too out of place there either!  

[celestron8g8]

The thing is do you have proper balance on your axes ? To me it looks like all it’s doing is making your OTA. Top heavy therefore youll be over working the mount motors to keep the scope balanced . That also could cause trailing in an image . 

[Stu]

1 minute ago, celestron8g8 said:

The thing is do you have proper balance on your axes ? To me it looks like all it’s doing is making your OTA. Top heavy therefore youll be over working the mount motors to keep the scope balanced . That also could cause trailing in an image . 

I’m sure it is simply countering the weight of the mirror. These scopes tend to be very back heavy, hence the need for the counterweight.

[Knighty2112]

12 minutes ago, celestron8g8 said:

The thing is do you have proper balance on your axes ? To me it looks like all it’s doing is making your OTA. Top heavy therefore youll be over working the mount motors to keep the scope balanced . That also could cause trailing in an image . 

If I release the clutch with my 2” Baader click lock, Vixen flip mirror with EP fitted in and my camera attached without the extra weight I’ve fitted to the front the OTA sinks down to the lowest level possible at the back end (scope ends up pointing upwards). With the added weigh on the front end of the tube then when I release the clutch the scope remains exactly balanced regardless of whether I push it up or down one way or the other. The majority of the weight in my SCT is at the rear end like Stu says mostly because of the weight of the mirror. 

[celestron8g8]

5 minutes ago, Stu said:

I’m sure it is simply countering the weight of the mirror. These scopes tend to be very back heavy, hence the need for the counterweight.

On my C8 which looks the same counter balancing the OTA itself the main weight isn’t so much the mirror to worry about , it’s what all is attached to the rear cell , the weight if the EP is the biggest deal , but also the diagonal or things added such as the barlow or any extentions . But extra added weight to the front of the OTA  off the dove tail could possibly cause flucturing or flexing of the OTA cause it’s attached to the dovetail . If there is any bending detected with the OTA it can cause light to bend and giving off color to an image taken throught the OTA itself , but the main thing is even if you have the OTA counter balanced perfect if the counter balance for the mount is not equal to balance it can cause stress on motors and axes gears . 

[celestron8g8]

When you balance your rig are you attaching all equip your going to use to the OTA and then balancing your rig ?? If not then your doing it wrong , but if you are then sliding the OTA forward on the dovetail mount should be sufficent for counter balance . 

[Knighty2112]

6 minutes ago, celestron8g8 said:

When you balance your rig are you attaching all equip your going to use to the OTA and then balancing your rig ?? If not then your doing it wrong , but if you are then sliding the OTA forward on the dovetail mount should be sufficent for counter balance . 

Yes, I balance it always with whatever equipment I attach to the end of it to make sure all is hunky dory. 

[Stu]

31 minutes ago, celestron8g8 said:

When you balance your rig are you attaching all equip your going to use to the OTA and then balancing your rig ?? If not then your doing it wrong , but if you are then sliding the OTA forward on the dovetail mount should be sufficent for counter balance . 

I'm sure these scopes are all similar. With both C8 Edge and C925 I recall having the scopes pushed well forward so I'm not surprised at the need for front counter balancing with heavy kit at the back.

The tubes are pretty stiff to keep the optics aligned so I very much doubt anything Gus is doing would cause any impact at all on the image.