Replaced Broken Plastic Rack on Travelscope 70

[Stargazer33]

Having suffered for some while with broken teeth on my Tracelscope 70s plastic focuser rack; I finally got around to doing something about it.

First of all I cut a piece of aluminium (aluminum for our friends across the Pond 🇺🇸) the same size and dimensions as the plastic one on the focuser tube. Using the damaged one on the tube as a template, I marked out the replacement and began to file it down to size. Once this was done I copied across the positions of the valleys between the teeth onto the aluminium replacement. Using a manual mitre saw with a blade suitable for metal I cut the valleys. Some rough filing and the rack was almost complete. A hole was drilled at each end to receive a screw. I then cut off the plastic rack from the focuser tube, filed the cut flat and the glued and screwed the replacement into position.

Due to the rough hand marking, cutting and filing it is not 100% smooth running, but at least it gives me full travel.

A couple of pics:

                                                          

                          Broken plastic rack (removed).                                                     New aluminium rack glued & screwed in place

[Oldfort]

Wow.  That looks like a lot of effort.

[Stargazer33]

It was a bit. Spread out over a few days though. I have been keeping an eye out for a spare focuser tube. I thought Astroboot might have one, but I've only ever seen a 0.965" focuser tube offered on there, so I decided to just bite the bullet and make the rack myself. At least I can use my scope again.