Newtonian Baffling and Tube Currents

I have a 10"/f5 Steel tubed Guan Sheng reflector, clone of the old Orion XT10. I wish to baffle the tube to eliminate stray light and reflections. The scope also suffers from tube currents. I have read several articles about baffling, including the S&T one by Gary Seronik. I have also read articles about ring baffles and used Newt 2.5 to calculate the positions of these. The problem I have is deciding whether to use ring baffles which I understand will worsen the tube current problem or just use flocked paper for general blackening of the tube and baffle the focuser etc.

I am also considering installing a fan to fix the tube current problem, can someone advise which is the best way to do this on this type of telescope.

ie. Do I suck the air down the tube or blow it accross the face of the mirror etc etc. I have a number of 12 volt computer type fans which I think would be suitable for the job.

Has anyone addressed these issues with this particular telescope(yes there are lots of them out there) and advise me the best way to improve its performance

Thanks in advance.

Clear Skies
John Bambury

I think you would be happier with the flocking approach. I would recommend the variety sold by McMaster-Carr in Atlanta that has no adhesive backing. It is easy to apply with white glue such as Tite Bond II. It does make a big improvement in what you see looking down the tube, like a black hole.
I have personal experience on my on 10" dob with the fans. I ended up directing the fans across the front of the mirror with holes opposite for the air to flow through. In a steel tube such as yours, you will almost have to use hole punches designed to cut holes in thin wall metal. I believe they are called chasis punches. No matter how you attack the project the potential is to mar/scratch the finish of the tube, naturally undesirable. However, with proper care it can be done. Of course, one could cut two largish rectangular holes on either side and then cover with screen material to act as a filter.
FWIW, I have removed the fan from my dob as I have discovered that it stabilizes fairly quickly anyway, and the fans become less effective after an hour or so.

Walt