pmrid
28-08-2009, 01:48 PM
OK. I'm having a bad day. That said, it all began with the snake and just got worse. But that's another story. The story of my moment is the joys of flocking a GSO Ritchey-Chretien. I read Paul's notes and thought that looked oretty straight forward. Disassembled the scope, removed the baffle tube -- and that's where things started to go wrong. Instead of the baffle tube coming off, the whole mirror retaining collar came with it. Well, I thought, that shouldn't be a problem. I'll have to re-collimate anyway.
So off I went flocking away happily, getting things stuck to things you don't want, using 3 times more material than the job needed and so on. But in the end, the job is done.
While all this was happening, I'd taken Paul's advice and put the primary mirror away in a safe dust-free place. Only when I went to get it out later, I found the mirror surface was speckled with what looked like condensation. No explanation for it; just plain wierd. SO I took the corner of a piece of tissue to see if I could gently soak up the droplets. Nope. Instead, the droplets smeared. Not water? Not sure. Did something manage to splash on the mirror? Dunno. So it was unavoidable. I had to do a mirror wash. Out came the mirror - because there was nothing retaining it any more, so it came freely. There was a plastic collar in the central hole and another plastic washer underneath. OK. Put those aside.
Wash the mirror ever-so gently. OK. All done. Nice and clean, dust free and no smears of whatever.
Time to reassemble. All seemed to go according to Hoyle - only this time, when all was re-assembled, the mirror had about 2 mm of play up and down and a whiskjer side to side. No amount of retightening seems to eliminate that play. What am I missing here? I can't get the mirror bck into a position where it will lock down. OK. I've probably done my warrantay. I knew that when I started. I just wanted to flock this darn thing: which I've done but in the process, I seem to have managed to stuff it up entirely.
Anyone want a nice mirror for the budgie?
Peter
So off I went flocking away happily, getting things stuck to things you don't want, using 3 times more material than the job needed and so on. But in the end, the job is done.
While all this was happening, I'd taken Paul's advice and put the primary mirror away in a safe dust-free place. Only when I went to get it out later, I found the mirror surface was speckled with what looked like condensation. No explanation for it; just plain wierd. SO I took the corner of a piece of tissue to see if I could gently soak up the droplets. Nope. Instead, the droplets smeared. Not water? Not sure. Did something manage to splash on the mirror? Dunno. So it was unavoidable. I had to do a mirror wash. Out came the mirror - because there was nothing retaining it any more, so it came freely. There was a plastic collar in the central hole and another plastic washer underneath. OK. Put those aside.
Wash the mirror ever-so gently. OK. All done. Nice and clean, dust free and no smears of whatever.
Time to reassemble. All seemed to go according to Hoyle - only this time, when all was re-assembled, the mirror had about 2 mm of play up and down and a whiskjer side to side. No amount of retightening seems to eliminate that play. What am I missing here? I can't get the mirror bck into a position where it will lock down. OK. I've probably done my warrantay. I knew that when I started. I just wanted to flock this darn thing: which I've done but in the process, I seem to have managed to stuff it up entirely.
Anyone want a nice mirror for the budgie?
Peter