On-Focuser Mounting Kit for ZWO ASIAIR and a Belt Drive for ZWO EAF

Some time ago I started to consider to get a new telescope to cover the focal lengths of around 420mm which would be basically in the middle of 550mm and 350mm of the Sky Watcher Esprit 100ED without and with the Starizona APEX-ED L reducer. While looking around, I discovered a similarity in the construction of numerous models of telescopes on the market. This sparkle an idea of a new mounting kit with a design which could easily scale and could be used to adapt for many models.

After quite some work, I now got something what helps to clean the mess of parts and cables

and to get a tidy system in a compact setup. 


I started with the TS-Optics CF-APO 70 mm f/6 FPL55 Triplet telescope, continued with Askar FRA 300 Pro, ZWO FF65 APO and lately adapted the design of the new kit for the William Optics ZenithStar 61 APO:

So what is the essential aspects which unites all them and makes it possible to adapt the kit for other models? All those four telescopes, like many others on the market, have a focuser body which holds a clamp for a finder or guiding scope. This clamp is pre-installed on one side and the holes on another side are covered by screws. The focuser body is long enough for such a clamp which provides enough space to put the ZWO EAF on the top of the body, between that clamp mounting holes. In many cases, there are tension screws for the rotator and for the locking of the focuser on the top side as well.

The design of the new kit places ZWO EAF on the top and shifts it slightly to the side so that it can drive the focuser knob via a belt. The hight of this placement can be adjusted via the height of the frame. The other side of the frame provides a clip for mounting of ZWO ASIAIR. The shape and the side of this side of the frame are different for each telescope. This is needed to make sure that there is sufficient space for cables and connectors.

Since the kit uses the mounting holes of the clamp which can be used for a guide scope, all versions of the kit provide a solution to place the guide scope. Some reuse the clamp and place it on another location, like here for the ZWO FF65 APO and Askar 65PHQ:

or here for the Askar FRA 300 Pro:

and others add a spacer for the clamp located in the saddle grip,  like here for the TS-Optics CF-APO 70 mm f/6 FPL55 Triplet and the William Optics ZenithStar 61 APO telescopes:

It took around 4-6 hours to adapt the design for each next modell including printing prototypes. In all cases, it was a weekend project and required the telescope being available for all measurements. The kits for these telescopes are available in the shop:

Feel free to contact if you have interest for a kit for your telescope.


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