Balacing dual plate with different weight OTAs

[Dangerous-Dave]

Folks, I've just bought a Geoptik 300mm side by side plate from another regular as the piggy-back set-up was restricting my guiding options to the Megrez and/or piggy-backed DSLR.

This works very well with

1. OMC140 and Megrez

2. Megrez and ST80/ADM rings

3. DSLR on ball-head and ST80/ADM rings

However, I have a balance problem when the OMC140 is in one saddle and my ST80 guidescope and ADM guide rings are in the other. I had assumed it would just be a matter of positioning the OMC closer to the centre of gravity but I can't seem to get the OMC close enough as its dovetail is snagging on the tightening screws for the Geoptik EQ6 universal saddle.

OK I can obviously use the Megrez to guide the OMC - which I've done before to image M1 - but it's difficult to find a guide star so I'd have to fit it to the guide rings which is a real shlep mid-session. I'd rather be able to just drop scopes in, balance the plate and be away, as I often change OTAs mid-session.

I was just wondering if anyone else had encountered a similar problem and had any ingenious solutions....? Obviously replacing the ST80 with a slightly heavier guidescope has crossed my mind, but it would need to fit 125mm guide rings, and I would want something similarly "fast" as I guide with a DMK21 which has a small chip.

D

[Kai]

A bit Heath Robinson but how about those ankle/wrist weights that people use in the gym.They are normally attached by velcro.

Or Lead flashing from a builders merchants

[Dangerous-Dave]

Cheers mate, the lead flashing sounds like a great idea, though I might be a little concerned about handling lead on a nightly basis!

[Ben Ritchie]

A bit Heath Robinson but how about those ankle/wrist weights that people use in the gym.They are normally attached by velcro.

I've used these weights for this, work very well.

[Dangerous-Dave]

I've used these weights for this, work very well.

Cheers, think I might give that a go. I take it they are long enough to wrap around an 80mm OTA?

[Ben Ritchie]

I take it they are long enough to wrap around an 80mm OTA?

Mine are. I picked up pairs of 0.5kg, 1kg and 2kg velcro weights from Tesco for a couple of quid a pair, and they go around a 160mm diameter refractor OTA without problems.

[Merlin66]

The velcro weights I got from Tesco are just not long enough to go around the tube of the ST80!! - bummer ( In the end gave them as a "present" to the wife!)

I have had similar problems with my dual plate dovetail/ HEQ mounting plate and found a solution by drilling countersink holes in the bottom of the dovetail and using 6mm c'sunk screws instead of the normal bolts. This allows the dovetail to be positioned anywhere along the length.

BTW I've had the 6" f3.5 Cometseeker on one side and the ST80 on the other; still managed to find a balance point!

[Merlin66]

Ben,

Just seen your post.

The ones I bought were the "Skywatcher" anaemic light blue 500gm each. With the velcro tab that came with them I can't get it to fit around the ST80 tube ( well dew cap to be precise)

Chinese standards???