Mount extra counter balance weight - your opinions :-)

[NorrinRadd]

I am in the midst of the quest for improved and longer guiding, which has lead to the path of adding some front counterweight to my C11 , as the Celestron HD Focal reducer weighs about the same as a small car  on the rear and balance is appalling even with the C11 tube all the way forwards.  

So....after fitting a solution   ie an ADM rail and front adjustable weight to move any declination balance as required, I now find the whole set up needs more weight in RA

The mount is a CGEM DX which only appears to have 22lb weights available for it as it has a fat bar so other smaller weights wont fit. I reckon I will only need about 7/8lbs of weight to solve all my needs.

My worry and questions are :

- If I add another 22lb weight on I guess I can balance it by moving way up the bar, but is this all too much overkill in weight going to cause me wearing out gear issues or is it irrelevant because its balanced? (apologies if this is obvious!) 

- Alternatively I have an home made option of adding some weight right on the tip of the bar by screwing in weights to the safety weight tip thread/screw , but this means the weight is way out on the tip so is this more unstable for tracking. (cheap though)

Sm I better off with too much weight but balanced or less weight but on the tip ? 

A third option is to buy say an 11lb CGEM weight and drill out the middle to fit the DX mount bar ?

Would really value your thoughts.

Cheers,  Simon

[Bizibilder]

Have you thought of using a conventional "weightlifters" weight - you can get them in cast iron or plastic from some supermarkets.  The hole is, I believe, 1.25" and should fit or can quite easily be made to fit with a sleeve of some sort.  They are much cheaper than a proper "astro" weight!!

[Carina Lass]

I cast my own add weight from some tyre balance weights.

If you only need a couple of pounds, it can be added just above the standard counterweight.

[knobby]

Or if you can find them, the stick on wheel balance weights might be an option? Stick them in between the weights...

[ollypenrice]

More weights closer to the centre (further up the bar) wins in terms of being balanced with less angular momentum. This reduces the load on the motors. It doesn't increase it.

Olly

[NorrinRadd]

Thanks for the suggestions guys much appreciated.

Olly thanks for that I did so set it might be the case re the placement.

So really I'm better off increasing and being able to slide up the bar , as I'm currently near the end of the bar already before adding the required min extra weight.

Following your info , I'm seeing if a friend of mine can knock one up with an screw on to the bar. Need to find the weight and he can lathe it . The hole size on the CGEM DX needs a 32 mm drill hole so he's got a farm with some serious metal work gear. The weights on the tip idea is being dropped !

Thank you . Simon

[opticalpath]

More weights closer to the centre (further up the bar) wins in terms of being balanced with less angular momentum. This reduces the load on the motors. It doesn't increase it.

Olly

Funny, without thinking much about it I always just assumed it would make no difference: small mass x large distance = large mass x small distance.  But of course that's the static balance case and angular momentum is dynamic = MVr, so much lower for the large mass/ small distance case.  Doh!

Adrian