Flip Mirror (FM) This unit is quite a help to astronomers that have to go out to dark sites, in other words portable. Finding and centering an object on your ccd chip can be extremely time consuming, not to mention frustrating. With the FM, after you have once adjusted it, all you have to do is flip the mirror down, center your object and focus as best you can by eye, and then flip the mirror up and your subject should be on your chip. All that is required then is final touch up focus.

Flip Mirror, CCD camera on AP refractor

Flip Mirror, CCD camera on C11 SCT

Flip Mirror on AP refractor

Motorized Filter Wheel (MFW) This is a 6 position, stepper motor driven filter wheel. It is 5 inches in diameter, about 3/4 inch thick in the body, not counting the stepper motor cover. The reason for the 6 positions is that IF one is using UBVRI filter there is still a clear position thru which to focus. If the clear position is equipped with a clear glass filter the same thickness as the photometric filters, then there will be no focus shift between filters. All the electronics are in the hand control box, none in the filter wheel housing itself. The hand box allows manual push button advancement of the filters, and has an LED that changes color to indicate which filter is in the optical path. Cables from the hand box allow for the connection to power, anything from 12 to 18 VDC, and to computer control of the filter positions. The computer cable is terminated in a DB-9 connector for serial port use. If the MFW is used with a SBIG camera then software from SBIG and Software Bisque will control it. MaxIm/CCD does an outstanding job of controlling the MFW and also allows it to be controlled from the parallel port. I also have a small stand alone Windows program to control the MFW is this is more desirable.

Motorized Filter Wheel Flip Mirror (MFWFM) This is simply the Flip Mirror and the Motorized Filter Wheel connected together as one unit. They can be separated and each used individually.

Motorized Filter Wheel,
CCD camera on AP refractor

Motorized Filter Wheel and
Flip Mirror on AP refractor

Motorized Filter Wheel, Flip Mirror,
and CCD camera on AP refractor

Bayonet Dove Tail System (BDTS) This is an item I designed and built quite some time ago to replace the narrow dove tail systems currently on the market. Unfortunately when a large or heavy scope is attached to a mount by the use of the normal dove tails a large and long lever arm is introduced leading to flexure and unwanted movement. Also trying to slide a heavy scope mounted on a regular dove tail can be quite an exercise in frustration and possibly worse, a catastrophe as it slides out the other end. My solution is to use a wide, up to 5 inches in some cases, plate that attaches to the scope and simply bayonets into the receiver plate that is attached directly to the mount top plate and in some case it can even replace the mount top plate. One simply partially over laps the scope plate to the receiver plate and allow the receive plate to drop into the receiver plate. Once in placed the scope can be moved for and aft for balance, and locked down. The design does NOT allow the two to slide apart once engaged. The locking screw system is composed of 5 to 7 screws which bear against a solid brass gib preventing the screws from making any contact with the dove tail surfaces. This way the engaging surfaces of the dove tail can never be marred or damaged. Any number of scopes can be instantly exchanged a mount by having a mounting BDTS plate for each scope. Change over can be done in a matter of seconds.

Bayonet Dove Tail System on AP mount

Bayonet Dove Tail System and Scope
Cradle on AP mount with C11 SCT

Bayonet Dove Tail System
on AP mount (front)

Scope Cradle (SC) This is another item I designed and built to eliminate the problem of gross flexure when mounting large or heavy SCT type telescopes. The customarily accepted method of mounting these is to use two small plates that screw to the cast aluminum front and rear cells and then attach to a narrow dove tail bar.This allows a considerable bending moment to be introduced as the mount moves across the sky and weight changes. The Cradle is a precision machined unit that goes exactly one half the way around the actual body tube of the SCT. It is lined with a layer of hard felt to prevent any scratching of the paint. The scope is held into this cradle with stainless steel hose clamp style straps. This allows a dove tail mounting system to still be used on the top to hold anything one is inclined to mount up there. I also have tapped holes on the sides of the Cradle arms to allow mounting accessories lower down to minimize excess weight farther from the rotational center line of the mount, again increasing rigidity drastically.

Scope Cradle, Bayonet Dove Tail System
C11 SCT on AP mount

Scope Cradle with
C11 SCT & refractor

Scope Cradle no anodizing

Meade 16 inch Focus Lock and Indicator (MFL&I) A devise that allows the mirror of the Meade 16 inch SCT to be locked down and its position monitored by use of the indicator. Also minor focus adjustments can be made by varying the amount of locking force applied to the lock. The indicator will give position changes readable to .0005 inches. Installation of this unit does NOT require any disassembly. Just remove the stock air intake from the back of the mirror cell and replace it with this unit.

C-14 Mirror Lock and Indicator (CFL&I) (pictured right) A locking unit very similar to the MFL&I. It serves the same function but installs differently. It uses one of the existing shipping lock bolt holes to hold the indicator assembly and the other shipping bolt hole is used for the actual locking unit.

My Big Mount (MBM) I wanted a big mount, one that would carry 250 pounds or more of relatively short telescopes, one that was close coupled; that is have the scope mounting surface as close as possible to the RA rotational axis and bearings to eliminate the flexure inherent in other designs that have a large distance between the RA axis and the actual scope mounting surface. I also wanted the worm drives, as well as the encoders, to be totally enclosed so no dust, dirt, etc., could get in and cause damage. I wanted the axis drives to be by way of servo motors, not steppers. Finally I wanted something esthetically clean and good looking. Since nothing meeting my requirements was available at the time, I designed my own and built it. I think I have achieved my goals quite well.

My design is a little different than what the commercial builders do, but then my design ideas always differ from theirs. Each axis is identical to the other, each axle is 2 3/8 inches in diameter and uses 4 high precision thin wall ball bearings and one 7 inch thrust bearing, each. These are then pre loaded to about 1000 pounds per axle, and, when in the free state (clutches disengaged), will spin like a top with no friction. I provided NO axle locks, therefore no abrupt loads can be transferred to the worm gear assemblies while loading or unloading scopes to or from the mount. Abrupt loads can cause flat spotting of the contact areas of the worm wheel, not to mention the shock to the worm gear bearings. All other critical internal design items inside the mount are strictly proprietary.

The mount is not equipped with a "goto" system as of this time, and frankly I doubt that I will ever add one, unless somebody out there comes up with an excellent after market goto system that is affordable. Key words: excellent and affordable, these are usually mutually exclusive. I presently use 8192 count encoders so pointing accuracy is extremely good, to good at times as I have this hard to control desire to move the mount till the readouts go to ZERO. That, as many of you know, can be an exercise in frustration. All in all I couldn't be more happy with my design and mount.

My Big Mount (right side)

My Big Mount (front)

My Big Mount with rotating shelf


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Phone: (575) 437-4233
E-mail: andy@tularosa.net