ATM Advise on port-o-scroung-o-scope ventilation

[Dale Campbell <campbeld@abs-lcms.com>]

I'm building my first open tube scope (only my second scope) for my brother. His needs 
are cheap, rugged, portable and cheap.  Weight is not a consideration. It is 6 inch f/6.  
Purchased mirror.  Total cost without eyepieces ~$150.  I'm going to make a folding dob 
mount, but not there yet.  I thought I had come up good idea for the upper assembly 
support using 3 pieces of ½ inch conduit and a ring.  But like all my good ideas, someone 
else did it first.  It is similar to the jpg of recent memory with 2 tubes and a ring and 
the post in the archives using 4 tubes and a ring.  Sink drain focuser and single stalk 
mount.

My question is regarding the mirror box.  It is about an 11 inch cube inside diameter.  
The mirror sits about 3 inches off the bottom.  Will this allow enough air circulation to 
cool the mirror with no holes in the bottom?  No holes is preferable from a transport 
perspective, since it would mean one less cover to lose.  And holes in the bottom would 
need to be light baffled (not a lot of space under a 6 inch mirror).  Simplicity is the 
object here.  I'd rather not use a fan.  

Thanks in advance.

Best Regards,

Dale Campbell
Senior Research Scientist
Advanced BioAnalytical Services, Inc.
Ithaca, NY 14850 
USA

42°6'N 75°54'W