I've chosen to reverse engineer the Harold antique scope in CAD. It's a fun procedure. Besides keeping my modeling skills sharp in between client projects, it...
Equalizing shades of particular zone in Couder mask in order to find ROC of this zone is based on assumption that ROCs of two areas behind pair of openings in...
Hi mirror cell experts, I have made (via PLOP) a 6 point cell. Its 3 bars have pivots which are not "extremely" frictionless in rotation. How bad or good they...
Art, ... Zijl in his calculation used viscoelastic material Gap Pad VO Soft. www.bergquistcompany.com This material is used to conduct heat away from...
Art, ... After reading the article I am not so sure about size of "reinforcement". calculation was based on : -ideally flat mirror back, - Infinitely rigid...
It appears that my intuition has been reinforced by analysis and validated by others with a similar idea. Naturally, I am pleased to see that. The question...
Thanks, David, that's an extremely kind offer! I might take you up on that! However, a kind reader made a suggestion to look at the various special triangle...
As frequently happens the text of my first reply to Asad was deleted from the reply. It seems that this only happens on the atm_free group. It does not happen...
Hi folks, I have much experienced in grinding 4",6" and 8" mirrors and similarly today, i completed 12" f/9 successfully. But during polishing stage of each...
I received this post from Professor Irving Robbins who heads the Astronomy depatrtment at CUNY on Staten Island. He asked that it circulated as widely as...
Hi Art, "CHIEFspiegler" is actually "Schiefspiegler" pronounced with sh like in sheep. The name came from the book: "Der Schiefspiegler," in 1953 (Kutter...
After seven months I am finally nearing completion of my 18" F3.5 astrograph. I have taken delivery of the optics (got a small scratch on the coating of the...
Vladimir Galogaza ... What has "CNC offer" (very kind indeed), in common with cell construction theme. Why don't you change the subject (thread) for the...
I need to find someone who knows how to model non-standard situations into PLOP. Specifically I'm looking to model the performance of a standard flat blank...
Okay gentleman, I have completed the construction of my 8" cassegrain. While it does look good I have a problem. When I turned my new scope to the skies I...
For a free pdf copy of Alan Adler's Sky& Telescope article go to http://media.skyandtelescope.com/documents/Adler-MirrorFlex.pdf  Alan was one of the...
You've heard me speak about Gordon's skill as a mirror maker on countless occasions to the point where your perhaps sick of hearing it. You've also heard me...
Guy, ... Calculating center of gravity for triangle with geometry method is mathematical way to solve the problem. Physicist will propose to students different...
You may have some interest in my most recent blog article. It's about getting all excited about using math when figuring out how to measure and cut the...
We know the telescope scope was custom built around the late 1920's. However, when I examined the mirror I was surprised to see that it was made from plate...
... Hi Art, Nope, that's what going to happen. Flex.exe shows that for fast mirrors a spherical back of a particular ROC gives a better (theoretical)...
Art, The reason I thought a composite tool might be worthwhile is because you can just pour the hydro right over a tile sheet and not worry about sealing the...
Charles Mitchard wrote: "The mirror will be flexed after grinding the back face to a 59" ROC, 7 In" Hi Charles! I've not yet read the Adler article on flexing....
I have a 10" well made tool and i want to grind a 12" with it till fine grinding. Is this size of tool will create any trouble in grinding a 12"? ASAD ... ...
This seems to have cropped up just at the right time. I have just finished making the tool to radius the back of an 8" f3.7. The mirror will be flexed after...
The article was more informative than I remember, but I did remember that the pusher system provided the best correction. I was a little surprised (since I...
On April 24th I gave a brief presentation to the members of the NJAA, our astronomy club. Afterwards a member of the audience, the friend of a friend,...
Mark Whitaker wrote: "You may have to dig through old Sky and Telescope magazines for the original articles." I went to their site Mark and, using their search...
