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Mounts that we upgrade receive attention to the existing mechanics (worms / wheels / bearings) to ensure that they leave us in tip top condition. There are many consistent design failures we try and correct, the worst being the use of roller bearings as thrust bearings in particular in worm axles. Bear in mind that end float is important so these tend to be done up tight. However if the telescope is knocked, a huge force is generated on this end-float bearing and it can distort the casings of roller bearings. We see this is a 'notched torque' requirement when it rotates. Prevalent mostly on EQ6 product where they tend to get loaded to the limit. All telescope drives should have a smooth and even torque requirement throughout the rotation of all the axles. This needs to be checked by hand.


It is easy to replace the motors and electronics on this superb mount. It is well engineered with phosphor bronze wheel and steel worms. The worm housing and bracket mounts on with M5 bolts and M5 grub screw adjustments pushing the worm into the wheel. The adjustments and locks make it a fit once and forget. The backlash should stay the same - the handbook says it is factory adjusted for life. However should you need to (we did on the mount that came in for a GOTO upgrade), first undo all the bolts and the backlash securing grub screws. The keeper plate holding the grub screws should be checked for tightness, then do up the M5 bolts mostly. The grub screws can then be adjusted by feeling how the shaft rotates. Tighten the M5 bolts and lock the grub screws! There may be an iteration here to get it right, but you know when it is done because the shaft should rotate by hand, and all the screws holding and adjusting the worm housing are done up tight.

The MOTOR/85 and timing belt fit on with substantial adjustable brackets.


Modified by adding MOTOR/85 externally with specially fabricated plates to allow adjustment of mesh of new pinion. DEC axis mounting requires extensive modification of the existing housing with large holes to cut in the casing. Absolute precision is not required as there are sliding plate adjustments, we have done all the ones to date. A base plate is fitted then the motor on a sliding stage is fitted. We recommend the wiring for the DEC motor be external to stop possible problems with cable wrap on teh internal wires. Some mounts have been manufactured with slip rings for all the connections, so it is quite safe to use the internal wiring. A 12V supply is required for the Centronics connector to power the internal polarscope illuminator.


Our motor assemblies on brackets simply bolt in place to upgrade to GOTO mounts with superior performance. These are small mounts and cannot cope with more than 10Kg payload else there will be abnormal wear of the moving parts. Over a degree per second for slew speed is the result.

If you have 5 pin or 8 pin MT-1 motors fitted we can drive them with our SYS5/VIX product at much lower cost. Our products drive the 5 pin motor to 10x sidereal and the 8 pin to 50x sidereal.


To the Fullerscopes MK IV mounting we add brackets to fix MOTOR/85 and a timing belt reduction onto the existing worm wheel brackets. We can service these at the same time, replacing lost ball bearings if necessary. They are getting quite elderly now but if the phosphor bronze wheel is in good condition then we can rebuild it from there. We have even sourced replacement worm to replace a bent axle damaged part. You get a fully capable GOTO system (normal 0.7 deg per second slew) with a quite decent load carrying capacity. They "scrub up nice" and several have been expertly refurbished to produce a spectacular telescope and mount.


Worm wheel sets modified with motors and timing belts in different configurations to match the load capability. Full GOTO systems result. We also supply substantial metalwork to fix the worm bracket in the correct place. For new mounts we can supply all these components. Many home-made substantial telescopes have been made with these components. The largest we have encountered is 24 inch optics. These excellent worm wheel sets have the correct engineering tooth profile for very low periodic error (5 arcsec rms) and the 12mm dia slow motion axles will not be bent! These worm wheel sets knock spots off everything else in this list. The nearest in quality is the Alter D6 in our view.


Alternative motors - two versions - (with timing belt reduction) replace the existing motor / gearbox and provides GOTO performance with around 1Nm torque on the slow motion axle for the MOTOR/50 and 1.5Nm torque for the MOTOR/85. Vastly increased power over the oem motor allows this mount to operate at its full potential.


The DC motors are underpowered in our view so we replace with our MOTOR/210 on a bracket bolted onto the worm housing with a belt reduction providing 3Nm torque on the slow motion axle. This telescope mount becomes a much more capable workhorse and the load carrying capacity during slews is vastly increased. The DC servo motors are configured as 200 step per rev stepper motors in order to operate them slowly.


A few of these have been done now. The worm bracket is really quite small and a serious consideration is the extra weight added by stepper motors so we only offer our small motor (MOTOR/50) on a 5:1 gearbox. Even so it generates 1.5Nm of torque on the worm. The earlier worms were small and this is just about manageable.


The Russian Intes-Micro mount works a lot better with our upgrade. The gearbox is over-geared and this is corrected as much as is practical. Our motors are not much bigger than the original equipment and it fits within the original casing. We achieve 0.55 degree per second during GOTO's at 12 Volt operation. Much higher speed achieved (1.2 degree per second) at 24 Volt operation.

We have also completely dismantled a unit for a thorough service. The main wheels have lost centres so they are quite tricky to put back together unless you make the correct 'V' block.


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