Modular Guidescope Rings






True No-Marr Clamp Screws

The basic concept of guidescope rings remains unchanged since the dawn of the telescope.  They consist of a simple ring with three radial machine screws arranged at 120 degrees, used to shift an auxiliary telescope to be aligned co-axially with the main instrument (or intentionally off axis for guidescope use).   In this simplest configuration the three hard-pointed alignment screws bear directly against the tube of the auxiliary telescope, causing inevitable damage to the telescope's finished (painted) surface.

Surprisingly, most currently available rings have evolved little from this basic design, and subject your valuable equipment to repeated damage.  The simplest and most inexpensive solution, taken by some manufacturers, is to add a small plastic cap or pellet inserted into the tips of the adjusting screws.  While this significantly reduces the damage, the rotation of the plastic screw tip against the telescope can still noticeably abrade a painted finish (particularly if there is any grit embedded in the plastic tip).  Also, often these plastic tips are made of too small a diameter, which result in high clamp loads that can permanently dent a guidescope tube.

The solution for this problem lies in enabling the plastic tip to freely rotate, so that as the clamp screw is tightened, the tip remains stationary relative to the telescope tube surface.  The clamp screws on our guidescope rings are designed in just this way.  Each clamp screw incorporates a large 12mm diameter nylon tip, in order to spread the clamp force and prevent permanent denting of a telescope's  thin wall tube.   The nylon tip is mounted onto the flanged head of a machined brass spindle, which inserts into a lubricated bore in the tip of the large diameter stainless steel clamp screw.  The net result is a rigid, truly no-marr adjustable guidescope ring.



One of the distinguishing features of our guidescope rings is their ability to be interconnected with each other, or to easily attach other auxiliary equipment (finders, pointers, etc).  Machined flats and mounting holes permit the rings to be assembled in a number of configurations, enabling you to mount and adjust multiple guidescopes, finder scopes, or other  auxiliary instruments.  These As shown in the image below, there are 5 locations around the periphery of each ring that have been machined as attachment points.  Each location has a machined flat, and a central 1/-4-20 threaded hole.  Note:  In order to couple multiple rings, you will need to drill out one of the 1/4-20 holes with a 1/4" drill, in order to bolt to the adjacent ring.


Shown below are some of the possible orientations that work for mounting 2 or more instruments:



The standard method for attaching these guidescope rings is to utilize the primary base 1/4-20 mounting hole.  Adjacent to this threaded hole are two unthreaded 5mm holes (28mm apart) that can also be used for additional mounting screws, or if your scheme requires screwing down through the ring into a base plate or telescope.  Of course, you can easily enlarge or modify any of the mounting features to suit your needs.  The extra heavy wall thickness and width of the rings makes them easy to rigidly attach to practically anything.



Product Pricing

Ordering Information


last updated 4/06/02



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