Giro Ercole: Satisfying at last !

[John]

I've owned a Tele Optik Giro Ercole alt-azimuth mount for a few years now. Although it's beautifully made and I really like it's simple but robust design, I've never been quite happy with the motion around the azimuth axis. No matter how carefully I balance the mount (and balance is important to the smooth operation of this type of mount) I have found just too much "sticktion" in the azimuth movement. Probably unfairly, I relegated the mount to a cupboard and only used it occasionally. I had hoped that the azimuth axis would ease over time and with some use but that didn't really happen. My Skytee II, although more crudely engineered and finished, operated much more smoothly and became my primary mount for my 100mm, 102mm and 120mm refractors.

I have recently dismantled the azimuth axis of the Giro mount to see what is going on in there. The original blurb on the mount stated that the bearings are "totally free of lubricants" but mine did seem to have some rather sticky grease that had been applied at sometime during it's life. I carefully cleaned all that off, re-assembled the mount and tested it with a couple of different scopes on board (with careful balancing again). Unfortunately the result was no better and the azimuth motion remained far too stiff for my tastes. So a "no-lubricant" approach did not really work, at least for my Ercole.

I took the azimuth axis apart again, cleaned it all again and then applied some decent quality white lithium grease. Not too much though - a thin film around the bearing surfaces and down the azimuth shaft that sits within the curvaceous body of the mount. I re-assembled the mount and was pleased, and a little surprised, to find that it's motion around the AZ axis was much smoother. It's now very close to the "butter smooth" motion of the altitude axis. Over the past couple of weeks, during the short clear patches, I have used the Giro Ercole with all 3 scopes mentioned above and found it a really pleasant and satisfying experience. With the 100mm and 102mm refractors I've even found that the mount is quite useable without the counterweight bar and counterweight fitted. With the 120mm refractor a small amount of counterweighting is needed so I use an old Vixen 3.2kg weight with that scope. With the smaller scopes, using a 1.8kg counterweight delivers a very smooth and well balanced rig which is a delight to use. 

Clearly, with my example of the Ercole mount, there is a "goldilocks" amount of the right sort of lubrication to create a really satisfying operation and I seem to have hit on that with my latest work on the mount.

Now that it is so pleasing to use, I can enjoy the sheer simplicity of the Giro Ercole mount coupled with it's capacity to provide very a stable platform for observing with refractors up to and including  the 7kg F/7.5 ED120. 

I have the Skytee II and also the superb T-Rex alt-azimuth when I want slow motion controls but I do enjoy the sheer simplicity of the Ercole design with it's fine seemingly unbustable engineering. Plus it's nearly 2kg lighter than the Skytee II, which is a bonus.

As owners of the excellent Rowan AZ75 and well sorted dobsonian mounts have found out, if a mount is really well engineered, properly balanced the need for slow motion controls diminishes as well because adjusting an objects position within the field of view, even at high magnifications, becomes 2nd nature - you start to do it unconsciously as you observe.

I'm very pleased that my Giro Ercole is properly sorted now and will, at last, become a very regularly used tool when I am observing with my 100mm - 120mm refractors 🙂

Here is the Giro Ercole mount on my Berlebach Uni 28 tripod. Now it really feels like an excellent combination of German workmanship 

 

 

Edited November 19, 2023 by John

[Stu]

Sounds like an excellent improvement John. I used to find my Ercoles pretty good, especially when balanced horizontally. They could be a little sticky with a heavier scope on, but freed up nicely when a counterbalance was added.

I must say, one of the things I like best about the AZ75 and AZ100 is that it doesn’t seem to matter how heavy the scope (within capacity) the motion stays smooth without counterbalance. Without revisiting old topics (😉) when mounts perform like that, the simplicity of just moving the scope by hand can be very simple and satisfying.

[John]

Just now, Stu said:

...I must say, one of the things I like best about the AZ75 and AZ100 is that it doesn’t seem to matter how heavy the scope (within capacity) the motion stays smooth without counterbalance. Without revisiting old topics (😉) when mounts perform like that, the simplicity of just moving the scope by hand can be very simple and satisfying.

Agreed, on all counts 🙂

 

[MalcolmM]

I also love the simplicity of this mount. It's very easy to use. Great for low power sweeping and great for star hopping. It is also easy to pan at high magnifications (×180 is no problem). I use it on an Innorel CF tripod, which struggles a bit for stability when extended more than one section, but that's a tripod problem, not the Giro. I have not yet felt the need for a counterweight with a 100DC or a Mewlon 180.

Malcolm 

[RT65CB-SWL]

That's why I like my AOK-AYO [left] and Tele-Optic Giro [right] mounts. No faffing around, etc., apart from balancing.

 

[pavel_s]

Hi, I have a related question.

I have Giro Ercole on top of Berlebach Uni (mount head: EQ5 without the pin). The issue is that the scope hits the leg when observing near zenith.

I'm looking for some extension, that will raise the Ercole a bit (10 cm would be sufficient). 

Do you have some advice or recommendation?

[RT65CB-SWL]

Hi @pavel_s

You can get extensions from about 21cms. FLO stock the SkyWatcher ones. https://www.firstlightoptics.com/search/for/Tripod+extension/ 

 

[pavel_s]

 

33 minutes ago, RT65CB-SWL said:

Hi @pavel_s

You can get extensions from about 21cms. FLO stock the SkyWatcher ones. https://www.firstlightoptics.com/search/for/Tripod+extension/ 

 

Hi, thank you for suggestion, but I actually dislike the build quality of SW extensions (not sturdy enough in my opinion). Are there any alternatives?

[John]

15 hours ago, RT65CB-SWL said:

That's why I like my AOK-AYO [left] and Tele-Optic Giro [right] mounts. No faffing around, etc., apart from balancing.

 

I've had a Tele Optic Giro II in the past and liked that a lot. It looked just like yours 🙂 The Ercole is made by the same people and has a little higher capacity I believe. I didn't have any issues with the smoothness of the Giro II azimuth motion though.

 

[John]

11 minutes ago, pavel_s said:

 

Hi, thank you for suggestion, but I actually dislike the build quality of SW extensions (not sturdy enough in my opinion). Are there any alternatives?

I've only used the Skywatcher HEQ5 and EQ6 extensions myself. They seemed very sturdy but the finish is not as good as the Berlebach tripod or the Giro Ercole mount. Rowan Astronomy makes some nice extensions - maybe one of those could be used ?:

Rowan Astronomy

[RT65CB-SWL]

11 minutes ago, John said:

I've had a Tele Optic Giro II in the past and liked that a lot. It looked just like yours 🙂 The Ercole is made by the same people and has a little higher capacity I believe. I didn't have any issues with the smoothness of the Giro II azimuth motion though.

 

I bought mine secondhand from fellow SGL’er @A McEwan and at the same time or year, I joined SGL. 

Edited November 20, 2023 by RT65CB-SWL

[Stu]

2 minutes ago, John said:

I've only used the Skywatcher HEQ5 and EQ6 extensions myself. They seemed very sturdy but the finish is not as good as the Berlebach tripod or the Giro Ercole mount. Rowan Astronomy makes some nice extensions - maybe one of those could be used ?:

Rowan Astronomy

Beat me to it John, the Rowan ones are a very nice design, beautifully made as you would expect.

[pavel_s]

23 hours ago, John said:

I've only used the Skywatcher HEQ5 and EQ6 extensions myself. They seemed very sturdy but the finish is not as good as the Berlebach tripod or the Giro Ercole mount. Rowan Astronomy makes some nice extensions - maybe one of those could be used ?:

Rowan Astronomy

Thank you, Rowan's extension looks very robust and will fullfill my needs. Only I have so make some budget for it