My astronomy project:
Repair and adjusting focus friction

Content:

Repair the friction coupling:

1. Introduction focuser
2. Disassembling the focuser
3. The friction parts
4. Assembling focuser together
5. Implement of high friction surface
6. Spring compensation load
7. To be continued

Related projects:

• Repair and adjusting focus friction
• Tangent arm focuser
• Rack and Pinion focuser
• Push and Pull focuser
• Focus and camera rotator
• Focus and temperature drift

Note:
I take no responsibility or liability for what are written here, you use the information on your own risk!

5: Implement of high friction surface

The last month I haven't used the telescope, of course I then got lot of nights with clear sky. This problem with the slipping focuser was difficult to solve without buying completely new equipment. But with that I also have to manufacture new adapters, it will be a bit expensive and take a long time to built.

The last week I concentrated me on the problem, too low friction. The diamond shape surface will sure helps but difficult to make by myself and I don't know any other who can do it. TS can deliver new spare parts, but they don't either have the diamond shape surface.

Are there any other solution? Maybe I have found one that is worth to spend some time on. What has high friction? Sandpaper! I have tested with different sand papers and what I found wet sandpaper grid 2000 seems to give highest friction.

My idea now is just simple glue the sandpaper on the steel surface. One drawback is of course, if it slips then the axis surface will be a bit rough. But I can't use it as it's now so nothing to worry about. The simple test I did was just to put the sandpaper in between the steel plate and axis. Result, very high friction, tight and stable as rock!

I cut out a piece of sandpaper that would cover the steel plate.

Now I just glue them together and let them be under press over night.

This is how it looks after the glue has dried for a day. A relative smooth surface.

When I adjusted the force on the axis I found that I can now have a bit less force relative earlier.

All the mechanics mounted to hold the motor focus and Hub device, ready for a test.

No idea for how long the sandpaper will last, but if it worn out, I just have to glue a new one on the steel plate.

Don't do what I have done here, maybe it will destroy your good focuser. Let me do some test first !