2" collimation sight tube?

[garymck]

Hi,
is anyone aware of any 2" collimation sight tube available in Australia? Need one badly to help collimate my 12" newt. With the dollar where it is, the price from the US is more than I can spare at the moment.

Alternatively, if I could find some 2" aluminium tube I could make one, but can't find any available here :-(

cheers
Gary

[iborg]

Hi


I don't have an answer for you, but, I am about to 3D print something similar for an SCT (in order to check position of the secondary).


I'll put it on thingiverse over the weekend, and link here. Have a look, if you think it may help, let me know and I can print up another. Alternatively, talk to the 3D printing people elsewhere on the forum, they will do a better job, and possibly know a more suitable design.


Philip

[Andy01]

Try the guys at Sidereal trading (https://www.siderealtrading.com.au/) - Diego used one to check collimation of my newt recently. :thumbsup:

[sharkbite]

Does it have to be aluminium?
Could you use PVC?
50mm pipe and end caps abound at plumbing stores...

[garymck]

thanks Phillip,
I tried 3d printing one - a ten hour print ! It ended up 1mm too small - don't know why, everything else prints perfectly :-). I ended up using a 1.25" sight tube that I cut to the correct length (sight tube ID x Focal ratio).

sharkbite,
I had already tried making one out of 50mm pvc pipe but I was unable to get it to centralise correctly in the focuser - wrapping tape around it is not good enough :-(

Andy01,
will follow up with Sidereal Trading

cheers
Gary

[sharkbite]

.....Damn....

i have always said that plumbing pipes can do everything....
and that Duct tape could fix anything....

Seems i'll have to change that to "most things"

:-(