Reliability of black saturn scope tube lining?

[Quark (Trevor)]

Hi All,
Have been thinking about giving my scope a bit of a birthday and am considering lining the tube internally with black saturn.

My scope is an observatory mounted 16" f4.5 Newt and the internal surface is already flat black. I recall running into various atm'ers at various SPSP's that had done this.

With black saturn there should be a reduction in internal reflections and it should contribute to greater contrast.

Was wondering if anyone at IIS had done this and what their experience was over time, what they used to glue it in and how successful it was.


Regards
Trevor

[Quark (Trevor)]

Greetings All,
I know that I posted satin but I meant velvet.
I fancy that years ago a ran into a guy from Canberra at the SPSP that had lined his scope with black velvet, even had fitted several baffles in his tube.

Regards
Trevor

[iceman (Mike)]

I've got the flocking inside mine, but if yours is already painted flat black, I honestly don't think it'd be worth doing the flocking.

I think the improvement would be so minor as to be unnoticeable.

[Quark (Trevor)]

Originally Posted by iceman

I've got the flocking inside mine, but if yours is already painted flat black, I honestly don't think it'd be worth doing the flocking.

I think the improvement would be so minor as to be unnoticeable.

Thanks Mike,

I am only considering this as, having read your article on mirror washing, I am thinking about stripping out my tube and washing my mirrors.

My scope is now about 14 years old and has always had fitted end covers on it plus a dust sheet over the lot, when not in use. My mirror still looks in fare condition, being in an observatory in Broken Hill means that there has never been any dew on it, that is I just don't open up if there is the possibility of dew getting on my optics.

However there is enough dust on it, that I am noticing a fare amount of scatter with my Laser. I use an EZY collimator double pass Laser, their MK II and the scatter caused by the dust on the mirror means that the return beam tends to be spread more than it should. The internal surface of my tube also needs a thorough cleaning to get rid of the build up of dust etc on it. Obviously to clean the internal surface of the tube the mirrors need to be removed.

Being a 16" scope this is not a project to be taken lightly. My remote location means that if I do stuffup and my mirrors need re-coating it is a major hassle to safely transport them the 1000 km to Sydney to get the job done.

If I do strip the tube out then I would have the opportunity to line it and maybe fit some baffles. There is no way that I would consider stripping out the optics just to line the tube or insert baffles.

Regards
Trevor

[iceman (Mike)]

I'd definitely wash your mirror. And if you've got it apart then you could fit some baffles at the top and bottom ends. But I wouldn't worry about end to end flocking.

[Rick Petrie]

The last time I had my scope apart to clean the mirrors I noticed that around the bottom part of the tube and some sections inside there was rust.(steel tube!)
I also thought of flocking but with the rust problem and future dew moistening the flocking, this would tend to promote further rusting down the track.
With this in mind and needing to fix the rust I searched for a product that would solve both problems - eliminate the rust and sufficiently blacken the tube.
There is a product made by White Knight called Rust Guard Flat Black Epoxy Enamel and you can buy it in a spray can. (no affilliations). This product, following removal of the rust, can be sprayed inside the tube and will leave a very smooth black matt finish and is also self priming. After taking all the bits off the scope, sanding all traces of rust, a couple of coats will leave a good finish that I have found is probably as good as flocking. Might be worth a try.
Cheers

[monoxide]

I re-painted the inside of my 12" tube and added an A4 square of self adhesive felt behind the secondary and also added some baffles just above the primary.
to me it seemed to improve the contrast quite a bit visually but id say its pretty subjective, some people swear by flocking and baffling the whole tube and focuser and others dont think it makes any difference at all.
i think its worth it anyway, especially if you are already taking the mirrors out for a clean

[kinetic (Steve)]

Originally Posted by Quark

My scope is now about 14 years old ........

Being a 16" scope this is not a project to be taken lightly. My remote location means that if I do stuffup and my mirrors need re-coating it is a major hassle to safely transport them the 1000 km to Sydney to get the job done.

If I do strip the tube out then I would have the opportunity to line it and maybe fit some baffles. There is no way that I would consider stripping out the optics just to line the tube or insert baffles.

Regards
Trevor

Hi Trevor,

The mirror in the 8 has been re-mirrored twice.
I sent it to AOS in Sydney both times in the original 'packing crate'
box Dad made.
I can't see why you couldn't scale some sort of box like that up and still
freight it over. I can show you pics of it if you like.
It's a snug cell with minimal point contact and the mirror came back
SOOOOO beautiful.
Besides, did you know you can get it done here in Adelaide too?
I'm not sure about overcoatings though. AOS did a protective coating
as part of the deal.
I'd recommend checking the secondary too because being a first surface
mirror, they too suffer from cleaning/scratches, mould etc over time.

As far as 'black Saturn' goes...LOL, as has been mentioned here a lot,
baffles are the way to go for a big Newt.
The baffles will do more for contrast than flocking, as long as the flat
black paint is truly flat...many flat blacks end up with a bit of a sheen
to them....

FWIW, you probably won't read this anyway.

Steve.

[Quark (Trevor)]

Thanks Mike, Rick, Monoxide & Steve for sharing your experiences on this subject.

Trevor

[Kevnool (Kev)]

Trev if you need sone elasticized black satin the same as my shroud call me and its yours.....cheers Kev.

[Geoff45 (Geoff)]

Try sawdust and flat black paint.

• Take out optics
• Apply generous coat of flat black to the inside
• Before it dries, throw in a handful of sawdust and roll the tube round and round to spread
• When dry tap out any loose sawdust that has not stuck to the paint.
• Recoat with flat black, using a sponge.
• Replace optics

Guaranteed to have no internal reflections

[Ian Robinson]

Try Edmund Scientific , they sell the stuff in sheets (either self adhesive or non-adhesive).http://www.edmundoptics.com/onlineca...productid=1502

http://www.tomhole.com/Flocking.htm

Also http://www.fpi-protostar.com/flock.htm


Not sure who sells it locally - it's called flokking paper. http://www.iceinspace.com.au/forum/a...hp/t-2394.html