MadMat Posted March 23, 2016 Share Posted March 23, 2016 (edited) Yep, Lloyd, I used to use 3 minute washed rouge for "figuring" and 5 minute washed rouge for final polishing. ** Opps! It shows how long it's been... I would "figure" with 5 minute rouge. For final polishing, I used to let it settle for 24 hours, and then used what was left suspended. Edited March 23, 2016 by MadMat Link to comment Share on other sites More sharing options...
lloyd Posted March 23, 2016 Share Posted March 23, 2016 I hate to tell you how long it's been, but the last one I did, I got within 1/8th wavelength of perfectly paraboloid, It took a LONG time with my Foucault tester to do that, I tell you! And - duh! - it was just for a simple Newtonian! I never did any perforated mirrors for complex optics. Now, 1/10th wavelength finished mirrors (already aluminized and over-coated) are so inexpensive, it just isn't worth the weeks of time necessary to grind and figure and polish your own, and THEN have to send it out to a vacuum house to have it coated. Lloyd Link to comment Share on other sites More sharing options...
MadMat Posted March 23, 2016 Share Posted March 23, 2016 Yeah, I gave up on making and bought a Nexstar 11 sct..... I got it for dirt cheap from an estate sale (Yeah I know, this is off topic, so I'll shut up from here on Link to comment Share on other sites More sharing options...
lloyd Posted March 23, 2016 Share Posted March 23, 2016 Same here:ON the original topic -- Patrick got a visit from another pyro friend DBY, and they got past the sticking problem (mostly). He switched him to a 'known good' clay (Dr. Elsey's Precious Cat), and they came off alright. In addition, Patrick showed hi-res pictures of his spindle. It appears to have a short portion just above the divergent cone of the nozzle former that very well could be 'reverse tapered'. It sure looks that, to me. So, he has a new spindle on the way that will be verified not to have that defect, and he has a new clay to fool with! Lloyd Link to comment Share on other sites More sharing options...
OldMarine Posted March 24, 2016 Author Share Posted March 24, 2016 Pressed several 1 and 3 lb rockets last night and had little problem removing them from the spindle. I think the clay was definitely my biggest problem. The 1" still didn't come off quite as easily as Caleb's did in his video but was manageable.I did notice that my 1 lb u/h set made by SLD has a more noticeable taper than my 3lb set. Link to comment Share on other sites More sharing options...
OldMarine Posted March 26, 2016 Author Share Posted March 26, 2016 Got my new spindle from Caleb and what a difference! With a graphite/clay nozzle these twist off the spindle with just my hand.Going to my ex wife's place to launch a few. Hopefully someone besides her will run the camera. Link to comment Share on other sites More sharing options...
lloyd Posted March 26, 2016 Share Posted March 26, 2016 Yay! I knew you'd get it. Now... KEEP that darned thing clean and shiny at all times! Lloyd Link to comment Share on other sites More sharing options...
OldMarine Posted March 27, 2016 Author Share Posted March 27, 2016 Believe it or not Lloyd, I shined that spindle up like a mirror after each rocket. I "jacked it off" with "0000"steel wool and lubed it with the dry Teflon each time.The new spindle Caleb sent me is stainless steel with a much more noticeable taper. I figure I'll lose a bit of thrust and hence sound but all in all a good trade off if I don't have to trash 5 of 6 rockets! Link to comment Share on other sites More sharing options...
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