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Last WO EZ Touch question - i promise!

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#1 helpwanted

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Posted 28 June 2009 - 04:15 PM

first, thanks to all who helped with my other posts about this mount.

it took some effert to find all the parts needed, but i finally have a counterweight solution. the Omni 6" f5 weights in around 22lbs with eyepiece, so i needed something to take stress off the bearings.

in this picture, you see a 12mm bolt, 180mm long, with a nut/washer combo at the mount end... washers on the far end, a 7lb counter weight onto of 1/2" PVC pipe.... which needed to be whittled and sanded down for the counterweight to fit in. i couldn't go without the pvc, since the bolt on the counterweight didn't reach the 12mm long bolt, and even if it did, it would have rolled around.

my last few questions...

7lb counterweight, sitting 10 inches from the center of the mounts axis... the otherside being the 22lb scope... am i okay with this amount of weight? i don't want to put more, but i do have more counterweights. will my set up balance stress on the bearings, or cause more?

also, with eyepiece and diagonal off, the scope needs to sit pointing zenith and the tention tightened a bit, to keep it from nose diving... is this an okay parking position?

i have a 16" pier extention on order, and the combined weight will be getting up there... any one have a wheely-bar solution? either pre-made or home-made? rolling this baby outside complete would make my day!!

thanks again for everyone's help.

david

oh, and the two M10 bolts seen in the picture serve no purpose, i just put them there to not loose them.

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#2 Sky Captain

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Posted 28 June 2009 - 07:22 PM

7lb counterweight, sitting 10 inches from the center of the mounts axis... the otherside being the 22lb scope... am i okay with this amount of weight? i don't want to put more, but i do have more counterweights. will my set up balance stress on the bearings, or cause more?



David, I use my 6" f8 for solar viewing with the 11 lb. CW on the other side. The scope weighs around 25 lbs. The bearings are sealed steel roller bearings...you'll have no problem putting a load on them. I have had heavier loads on the EZT and the mount handles great.

Nothing to worry about on that count.

also, with eyepiece and diagonal off, the scope needs to sit pointing zenith and the tention tightened a bit, to keep it from nose diving... is this an okay parking position?



No problem at all.

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#3 helpwanted

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Posted 28 June 2009 - 07:29 PM

thank you!

#4 GaryML

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Posted 28 June 2009 - 08:12 PM

Gently and carefully tip the tripod over to one side with the azimuth axis loose to test the balance. If it swings towards the scope side then you need more counter-weight. If it swings toward the counterweight side, then move the counterweight closer to the mount.

I had one of these mounts and they will work fine with one side heavier than the other up to about a 12-15 lbs. differential. For me, the main issues was to avoid too much imbalance in the tripod rather than stress on the mount. So if you have 22 lbs on the scope side and 10 lbs on the counterweight side you should be fine. And by moving the CW away from the mount you increase its effective weight.

One final note: I found some brass bushings to go in the counterweight hole to fill the space between the 12mm bolt and the CW hole. Worked like a charm and kept the CW from becoming lop-sided. Also, the CW can act as a convenient handle for moving the scope!

EDIT: Fixed typos & clarified balance test

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#5 helpwanted

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Posted 28 June 2009 - 11:12 PM

brass fittings... where was that idea two days ago! :)

#6 GaryML

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Posted 29 June 2009 - 10:35 AM

brass fittings... where was that idea two days ago! :)


The best option is a real counterweight shaft with a 12mm thread to fit the mount and the proper shaft thickness (25mm?) for the common Celestron CG-5/Meade LX-75/ Vixen GP CWs. But I couldn't find this anywhere.

My first attempt just used washers and I could not keep the counterweight centered on the bolt. I went looking for a sleeve to go over the M12 bolt to keep the CW centered, but then when I saw these bushings I knew that it was the perfect answer. Those bushings are shaped like a hat: there is a part that slips inside and what you see in the photo is just the hat "rim." The central hole fits the M12 bolt pretty well, and the small shoulder ("hat bowl") fits the hole of the Meade CW perfectly. I have one on each side and the CW is perfectly centered and very secure.

I am fortunate to have a really good industrial hardware store in town with hundreds of thousands of different kinds of bolts, nuts, bushings, etc. You can't find this stuff at the local Home Depot or Ace Hardware.

#7 Chris Schroeder

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Posted 29 June 2009 - 01:43 PM

What about attaching the weight to the Vixen side, any ideas? I use the WO Losmandy style plate and clamp for my 110mm.

#8 Chris Schroeder

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Posted 29 June 2009 - 01:43 PM

What about attaching the weight to the Vixen side, any ideas? I use the WO Losmandy style plate and clamp for my 110mm.

#9 GaryML

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Posted 29 June 2009 - 06:06 PM

What about attaching the weight to the Vixen side, any ideas? I use the WO Losmandy style plate and clamp for my 110mm.


I read on CN some time back that ADM makes a setup where he puts a threaded shaft on a Vixen-sized dovetail, and then you can use his standard threaded weights. I think it was about $100 for the dovetail, shaft and one weight. It's not in the Web catalog but he can make one up from stock parts. The real convenience is that the its easy to remove the counterweight without tools when transporting the mount.

#10 Chris Schroeder

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Posted 29 June 2009 - 07:02 PM

That sound like the ticket, thanks Gary.

#11 GaryML

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Posted 29 June 2009 - 07:38 PM

That sound like the ticket, thanks Gary.


You're welcome! :)

#12 Sky Captain

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Posted 30 June 2009 - 01:17 AM

I read on CN some time back that ADM makes a setup where he puts a threaded shaft on a Vixen-sized dovetail,


I made a similar set up with a dovetail cut to fit the exact size of the mounts DT slot. Drilled and tapped the center and made a stainless shaft to fit the Atlas counter weights.

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#13 Sky Captain

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Posted 30 June 2009 - 01:19 AM

Here is a close up of the pieces. Just some ideas on other ways to improve the EZT set up.

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#14 Chris Schroeder

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Posted 30 June 2009 - 07:43 AM

That look great Kerry!

#15 Sky Captain

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Posted 01 July 2009 - 01:41 AM

That look great Kerry!


Thanks Chris.

[BTW since no one asked...there was a pineapple just out of the picture. The top of it was the reflection in the polished aluminum dovetail on the counter.] :grin:

#16 Chris Schroeder

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Posted 01 July 2009 - 07:31 AM

Oh that's what that was I though it was from the hat you were wearing :lol:
I some how manage to get a part of me in a lot photos because of reflections.

#17 Sky Captain

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Posted 01 July 2009 - 09:00 AM

Oh that's what that was, I though it was from the hat you were wearing



:wron:






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