The focuser can be replaced easily and simply.

Product Description
The focuser is easy and straightforward to replace.

For example, with the SkyWatcher refractor, the old rack and pinion (OAZ) is unscrewed using three screws on the adapter, and the new Crayford OAZ is screwed back on using three new screws.

The OAZ may fit a little tightly into the adapter. However, you can either heat the white adapter ring with a hairdryer and/or place the new focuser in the refrigerator for a few minutes. This will expand the adapter or contract the OAZ slightly. If the new focuser is mounted flush with the adapter, the centering/alignment of the telescope is usually maintained.

Since most focusers don't have a finder shoe, you can attach a suitable finder shoe to the screw on the tube.

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