Herlp needed please......cleaning a Newtonion mirror

[UK1]

how can you clean a Newtoinon Mirror which you cant reach ... do you have to take the whole thing apart which sound to complecated for me thanks, by the look of it, it looks like dust particles.. must be lack of use
many thanks
Rob

[Space Dog]

Hi Rob, yes you will need to remove your Primary mirror from the optical tube of your Newtonion telescope to clean it.
However it is not as complicated as you may think.
Check out how to go about it with a step by step guide by reading the article on this subject written by Mike Salway in "Projects & Articles" on the IceInSpace home page.

Cheers, Ric. :)

[barx1963]

David Kreige and Richard Berry in their book "The Dobsonion Telescope" have very detailed instructions for washing mirrors. They recommend washing in situ, which for a Obsession style scope means not even removing from the rocker box. For a regular Dob, that would mean removing the mirror cell but leaving the mirror itself in the cell I guess!

[norm]

Hi Rob,

My main advise is NOT to get too worked on it. At the end of the day, IMO there isn't much to it. Just use common sense.

My main tips are:

1. Spray with water using one of those misting bottles to remove as much dust/grime as possible.
2. wipe over gently (no heavy pressure) with cotton wool strips dipped in water and detergent (only need a few drops of detergent into a bucket of water).
3. Use a spray bottle to remove the suds.
4. final rinse with distilled or de-mineralised water.

The mirror should be tilted during the cleaning process.
And the most important tip. Don't attempt to dry or remove any droplets using the cotton balls/strips. Let it air dry.

Good luck.

Norm

PS: something better than cotton balls/strips is these things called:
'Swisspers' woman use them to remove make-up and can be purchased at supermarkets or chemists for a a couple of bucks. They're flat shaped and larger than 6cm in diameter and come in packs of 80 - perfect for mirror cleaning - specifically cause they don't leave any fine lint or cotton hairs.:thumbsup:
(they are 100% cotton too and you'll only end up using maybe 2/3).

[DavidU]

A little different but works great with over coated optics
http://www.youtube.com/watch?v=9Y8xFnXFVGQ

[richardda1st]

Hi Rob.

I find removing the mirror to be very easy. I lift the tube assy of the dob base and stand the tube upright on a coffee table. Remove all the side screws from the cast ring at the base, then just lift the tube of and put aside. Make sure to protect the mirror from any possible damage that may be caused when removing/replacing the tube. Off course this depends on the brand of scope. Mine is a 10" Mead LB. :shrug:

-----------------------------------------------------

Thanks for posting that David. I've been doing something similar but using the shower with a hand held shower head and the mirror in a plastic bowl. Haven't bothered with the detergent and I use a few cotton balls which I gently drag over the mirror. I definitely rinse with distilled water. Works well.:thumbsup:
The demo reassures me that what I'm doing is OK.
Although I don't know if the LB has over coated optics.:question:

Cheers
Richard

[DavidU]

Cleaning a BIG one......

[erick]

You can try to keep the mirror in the mirror cell and wash it like that - remove the entire cell off the tube. Works well for a GSO solid tube. I've even seen one washed with the fan still in place. Just leave it all to dry out completely before reconnecting power to the fan.

[supernova1965]

Does that minimise the need to collimate Erick thanks for the tips everyone

[DavidU]

No. You must collimate often.

[erick]

Well, your collimation may not have changed much. The real issue is reducing mirror handling and the risk of dropping, banging it. Keeping it in the mirror cell should achieve this. You just need to be sure that, if you immerse it entirely, there is nothing from other than the mirror that might detach in the washing and find its way to the mirror surface. There usually isn't anything?

[Visionoz]

Take care in not dropping the mirror!

Cheers
Bill

[iceman]

Hi Rob

Here's how I do mine:

Cleaning the Mirrors of a Newtonian Telescope (http://www.iceinspace.com.au/63-345-0-0-1-0.html).