Casady Plates 18" Dovetail Tandem Bar
Manufacturer : Casady Plates
Part Number : RC22011811
Dovetail bar for mounting two OTAs side-by-side for imaging, or visual observing. Provides 14” of space between optical centers. Has mounting holes for Takahashi rings,
Robin Casady Dove8, Dove12, and Dove14 saddles. A Tandem Guidescope Aiming Device (TGAD) can be mounted between the tandem bar and the saddle or rings.
If you are using a guidescope for imaging, shooting with multiple cameras, or setting up a permanent observatory with multiple scopes, a Tandem Bar has advantages over piggybacking. By moving the OTA weight closer to the RA axis of rotation, the mount will be less strained and more stable. Less counterweight will be required to balance.
These bars are heavy-duty. They are machined from 1" stock with material carefully removed from both sides to relieve surface stesses and prevent warping during machining. Special care is taken to maintain flatness. The final thickness is appox. 0.97" in the thickest areas. The pads on the ends are reduced in height to keep the OTA as close to the RA axis of rotation as possible. The center area has material removed between struts to provide maximum strength without unnecessary weight.
Takahashi EM mounting holes with the appropriate circular depression are included on tandem bars. This allows the mounting of Takahashi clamshells and saddles without a dovetail saddle and bar. The four Astro-Physics 900GTO pattern (that matches my saddles) is still included, as well as a 1/4-20 clearance hole for mounting a camera.
There are a variety of ways to setup a tandem setup with one of these bars. Typically, a saddle would mount on each end.
