While wikipedying parabolic and spherical reflectors to get a better understanding of the theory, I came across a couple of methods for making them. Both methods have some degree of error, but could be a good way to get a close approximation. I figure one could use polished aluminum and a dremel/snips to do the cutting, the part I cant really figure is a good way to bend/hold it together without welding. I suppose one could screw clamp the top edges... but I'd imagein that there would end up being gaps down the sides of it if that's all you did... hmm... any thoughts?

http://www.solarcooking.org/plans/paraboli...-flat-sheet.htm

http://vzone.virgin.net/ljmayes.mal/var/parabola.htm

I did some testing with an elliptical and some other reflectors and luckyme did some test with a parabolic.

I now look at any reflector as a lens system in reverse. As the LCD gets smaller you can use a shorter and shorter fl condenser system. The shorter the fl the narrower the beam and the light in that beam will be brighter by the square of the area of the beam.

A reflector does the same thing. It makes a light cone at a certain angle.

As a condenser lens system fl gets really short it become less efficient and at some point you just can't make the fl any shorter and the light starts to have distortions from the lens. You could use two or three condenser but it is cheaper to just go to a reflector system.

So as long as the LCD is over about 6" or so there is vary little light gain to be had with a reflector system.

The shorter the fl of the condenser or the greater the collection and narrower the beam of a reflector system the larger the arc image magnification so all the light will not fit inside of our triplets.

I may still use an elliptical reflector system in a high power setup just because there is no glass to crack from the heat.

YWH did have a nice reflector for sale for cheep here.

http://www.lumenlab.com/forums/index.php?showtopic=23602

That is a nice part and a good price.

That reflector wont work with the bulb I'm using (Ushio), and I'm planning on using this with the 4" condensor off of ebay recently.

Any other thoughts?

Having so many segments may make it impossible to have the light distributed evenly. You probably would need a much smoother surface.
It may be still fun to try though. To hold the leaves in place you could try having a support structure on the back, like a mixing bowl, that you could screw or glue it to.

I'm in the final planning stages for my new HD PJ and I am going this rout. My design is similar but with about 3 times as many flat points. The current plan is to use a medium to thin gauge aluminum silver soldered together and then chrome plated. We’ll see how well the fab goes when I get to it.