♦ True No-Marr Clamp
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)
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
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.
last updated 4/06/02