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Old 11-07-2013, 10:09 AM
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Counterweight for EQ6

To use this mount for my 10" Newtonian, I need additional counterweight, cca 15kg in total..

So I decided to make my own.

The start was the round plastic 4 litres cake box ($2.50 at local shop) to be used as a mould and 1/2 bag of premix concrete, leftover from pier slab ($3.00?).

A friend machined for me the plastic tube with 18mm internal diameter (for counterweight rod), which I center-placed into the plastic mould (cake box).
I also added some reinforcement for the second half (actually, additional 5-7kg, as right now I already have 10kg).
Then the concrete was poured in.. now I am waiting for it to set and then to proceed with the rest (it was cold last night so the setting process is slow...).
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Old 11-07-2013, 10:15 AM
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Tinderboxsky (Steve)
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Excellent. A tidy up and some paint and it will look right at home on your mount. Reminds me of when I did the same thing on a larger scale to make a mooring weight for my yacht.

Steve.
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Old 15-07-2013, 03:55 AM
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awesome idea Bojan, I'll keep it in mind when I build my GEM
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Old 18-07-2013, 12:53 PM
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Nice work. I went with drilling out barbell weights, but this is really tidy.
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Old 21-07-2013, 04:59 PM
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It is on the mount.. 14kg total (10kg concrete, 4kg metal) is enough to balance my 10" Newt.
So, I need to add 6~7kg of concrete to the existing counterweight, that will be 2/3 of the cake box mould (just to cover the reinforcement, visible on the pics). The counterweight will then have to be 6-10cm closer to the OTA than it is now
If I need any more weight on the OTA in the future, I just have to move the counterweight a bit further away from the tube.
The total load on the mount will be ~35kg... a bit heavy but probably within the carrying capacity of the EQ6.
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Last edited by bojan; 22-07-2013 at 10:13 AM.
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Old 24-07-2013, 03:52 PM
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Phase 2..
The cake box was cut, so the additional concrete could be poured in.. the estimated outcome should be ~15k.
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Last edited by bojan; 25-07-2013 at 09:03 AM.
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Old 24-07-2013, 04:43 PM
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Bojan I had ninety lbs or 40kg of weight above the axes of the mount. Only the wind will beat you!

Bert
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Old 24-07-2013, 05:29 PM
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Quote:
Originally Posted by avandonk View Post
Bojan I had ninety lbs or 40kg of weight above the axes of the mount. Only the wind will beat you!

Bert
Nope.. if/when all this is housed under this.. (in the near future)
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Old 24-07-2013, 06:10 PM
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Nope.. if/when all this is housed under this.. (in the near future)
How are the electronics going?

Bert
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Old 24-07-2013, 07:28 PM
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Getting there.
Driver circuit is assembled, control is with SoundStepper (alternatively with Bartels (in step-dir) mode) and CdC/EQAlign.
New motors are here (400s/rev, http://www.ebay.com.au/itm/270871351...84.m1423.l2649), still need to machine the motor shaft ferules (to fit wider timing belt pulleys).
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Old 01-10-2013, 04:00 PM
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Quote:
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Nope.. if/when all this is housed under this.. (in the near future)
Hi Bojan, what brand of observatory is that?..........and how many $clams?

Rob.
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Old 01-10-2013, 04:46 PM
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Hi Bojan, what brand of observatory is that?..........and how many $clams?

Rob.
The brand name is "Bojan's Dome" .. . not sure about the final price, but it should be ~<2k$ in total (with automation).

Last edited by bojan; 02-10-2013 at 06:05 AM.
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