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ArcticMyst Security by Avery

Casio dichro figures

Morgan

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Hi All,

I originally posted these figures in another thread but it's useful information should anyone be planning to build with these. My measurements are as accurate as I can make them but as they're the first ones I've taken from a set of dichros then there may be small errors as the setup is so small. Either way, the measurements can only come out low so if anything, expect better results from any future build.

Here is the data I got all at 45 degrees:

Blue, (445nm A-140) - 143mW raw: After 1st dichro 130mW, (91% pass): After 2nd dichro 120mW, (92% pass).

Red, (650nm LOC) - 248mW raw: After first dichro 240mW, (97% reflected): After 2nd dichro 237mW, (99% pass)

Green, (Duh!) - 120mW raw: After dichro 105mW, (87.5% reflected)

Therefore:

Pass blue, (91%)/reflect red, (97%)
Pass blue, (92%) and red, (99%)/reflect green, (87.5%)

I think these aren't half bad but what would I know, right?! :tinfoil:

Any glaring errors or more standard ways to present this data then please point them out as I don't like making the same mistakes twice. ;)

Thanks,

M
:)
 
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I'm trying to figure a way to cut them perfectly.

I might get one of those diamond bit dremel bits and slowly etch some perfectly square cubes on both sides. If I have coolant flowing the whole time I don't think scratching would be a problem...

Any ideas anyone? You could cut these things down into a whole lot of little ones, they are quite large.
 

flecom

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how about a glass cutter? you know one of those little pen-like things that scores the glass with a wheel and then you snap it? or would the coating not survive that?
 
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I am looking for a little more precision than that. It would be pretty difficult to put one of those in a mill.

I'm attempting to do the same thing, only with a mill. I would only go deep enough to score the glass, not a full cut. I think if I lightly etched both sides I could then just snap them apart without having that ragged back edge that a wheel cutter usually leaves.
 
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There's a thing in the FAQ about cutting FS mirrors, would probably work for dichros, you cover the entire face with saran wrap and cut through with a diamond saw blade, should work for these dichros and a dremel wheel.
 
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I might try the saran wrap, but I want precisely cut pieces. Its really hard to do that with something handheld.
 
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There are some diamond tip glass cutters pretty cheap on FeeBay--or this is what I am going to try--my Dentist has offered to save me a few of the used diamond drills he uses on teeth-(sanitized for my protection--lol)- I am planning on putting them in my dremel and cutting some thin FS mirrors for practice- then try it on a dichro. I may even try to cut FS mirrors into circles- I have many free mirrors to waste til I get it right. I have some flat blade pliers coated with tape and a small vice to hold the glass while i try to snap it into clean breaks-- I think I can do a better(or as good) job than Dave did--I will post my results here- should be getting the diamond bits Friday.

hak

Morgan thank you for the testing--good job
 
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Morgan

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Putting on seran wrap would probably have helped too but this way worked really well. I gently pinched the dichros in ktichen roll where the jaws were and supported them with a piece of ally from the back. I hope that makes sense. I'll draw a sketch or take a photo if you need more. Oh, a little water was all that I used for lubricant and cooling but it would work just fine without. I made the first cut half way through then snapped underwater but the second cut I took the whole way through. That's the way I would do it next time too.

M
:)
 
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Score it with a glass cutter, but give yourself an edge to work with.. use a wood ruler or anything with a straight edge that won't scratch the surface. If you're mega picky you could stick a piece of lens paper between the straight-edge and the glass. Then you just snap 'em in half.
 
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I have used a nice sharp edge on a metal file to score glass.
Do as ElecktroFreak says
Get that score line right over the edge of the ruler below then use a 2nd lens paper covered ruler on top of the glass hanging over the lower ruler and apply pressure to the middle of the ruler till it snaps.
All it takes is a consistent scratch without breaks, depth helps only slightly
 
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I've cut microscope slides with a glass cutter with no problems. Just get out the sewing machine oil, and cut through the oil so it doesn't shatter your glass. Grind down the edges under water using a fine grained file (I used the nail file on my Leatherman).

I know that Daguin just outright snapped the dichros for his dichro sale. It should be just as easy, and cleaner, with a glass cutter.
 
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First coat the workpiece with collodian, paint or wax, then grip the dichro in a rubber jawed vice with a razor blade or ther flat piece of very hard metal facing the painted side to for your guide. Next scribe it with a diamond tool or carbide point bit and smap in the direction opposite of the scribe. When done disolve the paint with acetone DCM or other solvent of your choice. These dicrhros can be easily cut into fourths or eigths, maybe even 16th's.
 
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Hi All,

I originally posted these figures my, "Sneaky Peak", thread but it's useful information should anyone be plannig to build with these. My measurements are as accurate as I can make them but as they're the first ones I've taken from a set of dichros then there may be small errors as the setup is so small. Either way, the measurements can only come out low so if anything, expect better results from any future build.

Here is the data I got all at 45 degrees:

Blue, (445nm A-140) - 143mW raw: After 1st dichro 130mW, (91% pass): After 2nd dichro 120mW, (92% pass).

Red, (650nm LOC) - 248mW raw: After first dichro 240mW, (97% reflected): After 2nd dichro 237mW, (99% pass)

Green, (Duh!) - 120mW raw: After dichro 105mW, (87.5% reflected)

Therefore:

Pass blue, (91%)/reflect red, (97%)
Pass blue, (92%) and red, (99%)/reflect green, (87.5%)

I think these aren't half bad but what would I know, right?! :tinfoil:

Any glaring errors or more standard ways to present this data then please point them out as I don't like making the same mistakes twice. ;)

Thanks,

M
:)

I know this is an older topic, but I was thinking and I believe the reason the green's losses are slightly higher could be because of IR. The dichro will likely filter out any IR..
 

Benm

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Seems like these would make a very usable set of dichro's RGB combination. Surely you will lose nearly 20% of the blue in the process, but that will be the color you have plenty off. The reflection and transmission for red are impressive, and thats the thing you'd probably need most.
 




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