Orion Optics Variable Friction Brake

[greglloyd]

Hoping someone can help me with a little problem I have fitting an Orion Optics Variable Friction Brake?

I received this today. In the box came the two sides of the brake with the teflon pads. One screw with turn handle for adjusting the tension. And that's it.

There is a hex screw in each side of the friction brake which I had originally presumed screw straight into the side of the dob base where the holes are located for the brake. However, there is no way these would reach the side of the base. It's as if there should be some spacer or other component that should be there to mount the brake to?

I'd be interested in hearing from anyone who has one of these brakes fitted to a 250mm or larger OO Dob base to find out what I need to do.

Thanks

[jetstream]

The set screws adjust to touch the base and keep the pads square on the rings. There are little indents where the screw points fit, to keep things from turning when tightening. I put a little sealer on the set screws to help them stay in position.

[scarp15]

As above, Gerry's description and picture says it all really. Just maintain that the set screws are adjusted to the correct extent. I find the friction brake to be particularly helpful when swopping round e.p's, attempting to keep the target in the field.

[greglloyd]

Ok, thanks. It just seems that on the inside of the base the set screw would never touch? I'll take another look. Perhaps they will touch when the tension is tightened up enough.

So are you say that the brakes would quite loose and rattle a bit when the tension is not tight? I kind of thought they would stay firm in place when not tight?

[greglloyd]

Ok, got it now. That's it sorted. Working well now. Earlier I was busy trying to actually screw those set screws into those holes in the base! Thankfully I didn't go too far and it all still works!

The next problem is that I scored some of the paint off the altitude ring that the teflon pads grip on to (part of the tube ring assembly). It seems the metal bit in the middle of the pad rubbed and scored the paint away because I moved the scope up and down earlier when trying to get the way I had fitted it.

Has anyone fixed up the paintwork on their OO dob base before? I'm thinking some Hammerite but wondering if it's hammered effect or flat black? Have any of you had this problem with the friction brake scoring off paint?

[jetstream]

Hi Greg, the Al is powder coated, with a texture finish for the alt/az movements. They just coat the whole base pieces for looks and simplicity I think. I wouldn't be concerned with a bit of coating off the side of the ring, the brake will work fine.

The brake will rattle when loose, so I leave mine snugged up a bit. I may put a spring in there to keep things tensioned, but as I transport my scope a lot in 2 pcs I take the brake on and off a lot, and the spring may complicate this.

[greglloyd]

Thanks for the photo. That's how I have it set up now and it's working nicely. Just wasn't clear on the OO website shots. Cheers!

[greglloyd]

Lol at my typos above! Autocorrect on phones can be a pain ;-)

[scarp15]

Yep that's a good point, the rattle would be quite distracting, therefore when I travel with the base, I tighten the friction brake up, so that the PTFE brake pads are clamped together and in situ as they would otherwise be.