Collimating troubles.

[Thorney]

It's my first time trying this and what a mission (no wonder I put it off for so long)

I've got it the best I could and if its not right then I'm pretty stuck on what to do next. I was reading up online and after making a mess at first I think I have it the same as the pictures online, but I can't seem to tighten the secondary mirror with out it being thrown of centre and starting again. So would this be ok or once I move the telescope will it knock it off centre?

I haven't touched the primary mirror as it all looks ok to me but then it is my first time so I could be wrong?

[Moonshane]

hi there

the way to tighten the secondary adjusters (and it's important) is sequentially. adjust each one a tiny bit of a turn each time, going round and round until they are all tight enough. that way you should be able to do it without moving the secondary tilt from the correct position. doing this ensures next time you check it (i.e. when you are next observing) that it won't have moved. if when you tighten one of them move it back so the secondary is centred again and move onto the next.

eventually you'll get there.

it's important to do collimation in the right order. this other thread might help

[Thorney]

Thanks for the reply, I'll have to try and keep a steady hand then and keep my fingers crossed :-|

I'll check that link out thanks

Keep thinking the more I read and try the better and easier it will come.

[Moonshane]

that's the spirit! I'd say forget the reading and just practice while the dodgy weather is presenting itself. generally collimation looks wrong when it's wrong - look down the empty focuser and centre your pupil in the donut. you'll see what I mean.

[kirkster501]

that's the spirit! I'd say forget the reading and just practice while the dodgy weather is presenting itself. generally collimation looks wrong when it's wrong - look down the empty focuser and centre your pupil in the donut. you'll see what I mean.

+1

Couldn't have put it better myself. All we are talking about is tipping mirrors slightly with a few screws! Not splitting the atom. You can't break anything unless you are very ham-fisted. Get stuck in there!

[knobby]

My secondary has burr marks where the screws hit... Consequently it keeps jumping back into the burrs.

Filed it flat, now its much better

Might be worth checking

[umadog]

You can also add a couple of plastic washers to help with this. Cut up milk bottle material works well.

[Jason D]

You can also add a couple of plastic washers to help with this. Cut up milk bottle material works well.

[triton1]

I found a washer in my shed.I then polished both sides then with a felt tip coloured one side.I then removed grub screws from the spider,lined it up over the washer and spotted through with correct size drill.I then centre punched the marks and drilled three dimples(1-1.5mm deep)Then using a stone polished back of mirror holder. Mine was quite rough.Little smear of grease and sorted.Absolutly worked a treat.

Jonn