My telescope mount keeps moving after I release the arrow button. Is this backlash?

When you move your mount using slow-motion controls, there is a delay? Changing the direction of the motion is also causing the scope to slew in different directions?

You cannot seem to complete the alignment in your go-to mount? There is simply no accuracy and no results, no matter what you do?

This article will become your retrieve. This is true if you are facing either of the two problems or both.

Both this conundrum is a direct effect of a mechanical property of mount. The gears in your mount undergo what we call backlash.

We will discuss the plausible causes of backlash. After you are through with this section, you will be able to troubleshoot effectively.

What do gears do in a telescope mount?

Backlash in caused by the gears in your telescope’s mount. It is then fair to ask why you should use gears at all?

You cannot eliminate your mount even though it creates a backlash. Your telescope’s mount depends on the gears.

These gears make the shaft in the mount to rotate. The rotation occurs in the centre. The rotation is remarkably slow for better accuracy.

Our concepts of mechanics are still insufficient. This makes it impossible to build a perfect electric motor. The motor cannot rotate extremely slow and maintain consistency at the same time.

Why do your telescope’s gears have backlash?

We have now established the importance of gears in your telescope’s mount. Theoretically, you would expect them to function flawlessly.

The gears in the mount have different sizes. The speed of the second gear’s shaft is slower. The speed of the shaft is subjected to the number of teeth.

Precision is the key factor required for this mechanism. If any of the gears’ teeth are imperfect, there will be jamming or wear and tear.

Precision is necessary, but expensive. There is a cheaper solution to this quandary. Making the teeth slightly smaller or further apart.

This creates an airspace between the gears. This airspace compensates for all the imperfections in the gear system.

Dealing with the Inevitable Backlash

Backlash is especially annoying when you are aiming for precision in your telescope. Two ways will help you cope better with backlash.

Reducing Backlash

You can adjust the alignment and spacing of the gears in specific mounts. This is a perfect way to reduce backlash.

This is typically true for high-quality mounts. Such mounts have in-built gears. Low-grades mounts, on the other hand, have an external gearing system.

To adjust the gearing of your mount, you need to disassemble the device. It is not a not simple task, but a rewarding one, nonetheless.

There are two areas causing backlash. Hence, two approaches to solve the problem. Both methods are related to each other.

The gearing system of your mount’s manufacturing might be grainy. You can easily replace the low-grade gears with those that are high-quality.
You need to leave room for free play when mounting the gears again. With higher-end mounts, fine adjustments of both the gears are easy.

Suppose the gears are placed in proximity, the backlash increases. If you tighten the screws too much, the movement will be restricted.

These two factors make it essential to enhance gear precision. Then you can align them accordingly.

Compensating for Backlash

Even when you adjust the gear system of the mount, backlash exists. There are a few measures that will reduce it even further.

The Easy Method

If you are moving your telescope to a short distance, the backlash is not a significant problem. The easiest way to overcome it is to ignore the challenge.

Method for Motorized Mounts

For EQ mounts that have built-in motors, you can use an electronic control pad. This is a functional integration if your goal is to reduce backlash.

Backlash in Go-To alignments

The final region, which can be modified for less backlash, is the go-to EQ mount. For setting up the mount, you need to conduct 2-3 alignments.

Using hand-controls for alignment, the go-to computer will notice the directional changes. But the telescope’s movement is still insufficient due to backlash.

The result is a distorted observation. The go-to integration makes somewhat accurate, but not sufficiently.

It is simple to resolve this problem. Choose a direction such as left/right and add another to it.

Use the buttons on the hand controller to do the alignment. There is a certain benefit to using the same buttons on the hand controller.

The information with backlash error will never reach the go-to computer. This will give more accuracy to the operations.

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