[ATM] Plop Flop

[Jay Kirkland <jaykirk2@compusmart.ab.ca>]

Over the last 2 months, I think I've broken just about every drafting
template/too/pencil/etc I have as I've grown more and more frustrated with
trying to design a new mirror cell for my scope. The reason for my
frustration: yes, I'm a non-mathematician trying to use Plop. You'd think
that something with a GUI would give you a result that would be easy to
translate. Ha! I have no idea what any of this stuff means. So I thought
I'd take the easy way out and just plot the graphic full size and use that.
Which I did today. The graphic has the right angles, but the radii are all
way off. So when I draft up the right radii on paper, the angles make sense
but then the parts dimensions that Plop gave me don't match a single
measurable thing on the paper. Not even close. And where does part 4
balance anyway? Is it the COG of the part? And if it isn't, does the COG of
the part matter at all?  The Plop user manual is of no use. If anything, it
adds to the confusion. 
	Is there anyone out there who has actually successfully used Plop (man,
you have my greatest admiration and respect) who wouldn't mind taking a
crack at my cell design? I know it's asking a lot, but I'm absolutely
stymied. Or alternatively, if you've designed a 27 point cell for a 20" of
any thickness/focal length, my machining won't be to the millimeter
tolerances required by Plop anyway so I think any non-Kriege/Berry cell for
a 20" of any fl would work just fine. But in case, my specs are 508mm
diameter, 54mm thickness, 2895.6mm fl (yes, f5.7), and a 79mm obstruction.
I've been trying for a 27 point support, and have used Monte Carlo and not
(same results either way). All I need is simple Kriege/Berry-type #'s for
the triangles: base/altitude or outside/short side/third side, balance
point from vertex, and radius to balance point for the 3 (4) triangles. I
mean, all this stuff that Plop spews out, why can't it also  give results
in those terms for the rest of us??? AAAURGH!!!
	Huge thanks to anyone who can help!
	
Had a full head of hair two months ago,
Jay


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