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PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please sub

Bionic-Badger

Bionic-Badger

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

madmacmo said:
If you will, please let us know what you are able to work out, as I am intrigued by the possibilities but am intimidated by the daunting tasks of lens mount design, precise alignment, and host fabrication that others have described.
Click to expand...

Will do! I don't have fancy facilities for precise alignment, etc. but once I get the math and experimental part worked out maybe I can have them fabbed by people who do (or buy tools for it).
 





bennett326

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Bionic-Badger said:
Here's the thing with prism pairs versus cylindrical lenses:

- Cylindrical lenses are for focusing (collimating) a beam in only one axis.

- Prism pairs are for reducing the width of an axis of an already collimated beam (i.e. correcting aspect ratio).

The problem with those 638nm laser diodes is that each axis has a different divergence angle (7.5 vs 35 degree angles). So with a circular lens, one axis gets collimated, but the other still diverges. That's why you need to have separate collimation for each axis. Chances are, if you can collimate your beam, you won't have the exact optics to create a square beam--especially given the price of cylindrical optics. So now you can take the prism pair and correct one of the axises, or at least try and reduce the aspect ratio.

So here is what I'm going to do:

1) Use cylindrical lenses to collimate both axises; 2) use the prism pairs to reduce the beam diameter in one axis if there is a mismatch (this probably won't be perfect).
Click to expand...

wow that will be one hell of a build. and thank you for informative but easy to follow explanation :thanks:
 
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Cheech

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

6tool1.jpg
MINI Classic Lathe, 6 Tools in 1, Milling Machine, Sawing, Driller, Grinder
$199

MINI Classic Lathe, 6 Tools in 1, Milling Machine, Sawing, Driller, Grinder | eBay
 
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Alexizupinhea

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Cheech

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

looks workable but i wonder if it has duty cycles
@ 0:40
 
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Bionic-Badger

Bionic-Badger

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

That IS a cute lathe, but more like a micro-lathe than a mini-lathe. The writing for the commercial is terrible.
 
AUS

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

I was looking at that myself wondering what it would handle. I need something for small lathe & milling jobs.
 
scopeguy20

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Has anybody seen a good buy on a green HeNe power supply? -GH
 
Cyparagon

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

^The only fundamental difference between a green tube and a red tube is the mirrors. Electrically, they are virtually identical. As long as the current matches, or is close, a "red" power supply will work just fine.
 
ARG

ARG

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

AUS said:
Anyone want some 100 watt 808nm laser bar arrays? Currently sitting at $US10. I'm not bidding on these I don't have a 2.2V 110A power supply! 100W QCW 808nm Laser Diode Bar / Array, DPSS Nd:YAG Laser, Brand New! | eBay
Click to expand...

Not only finding a power supply, but cooling and collimating would be a pain as well.


EDIT:
Good deal for the yankies: (No shipping to Canada)

2 working, 1 unknown HeNe's 60$BIN
http://www.ebay.com/itm/3-SPECTRA-P...210?pt=LH_DefaultDomain_0&hash=item27cb884dd2
 
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AUS

AUS

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

Yes it says 35 degrees by 8 degrees, optics would be a nightmare. 45% efficient so you would need to get rid of 110 watts of heat, although that isn't that bad.

It would make a good 20-35 Watt 532nm DPSS if you could find crystals capable of handling the power (and if it was stable enough) !

Otherwise good for setting fire to neighboring houses or something.
 
T

Things

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Re: PERMANENT THREAD: Ebay& other internet FINDS of interest- read all the OP please

You can probably power that diode bar using a microwave oven transformer, re-wind it for 2.2Vish, rectify, filter & pass it through a linear passbank. Pretty inefficient though. You can get away with a variac if you give the diode a bit of headroom. MarioMaster has run a 80W bar this way.

In terms of beam specs though, CO2 lasers kick ass :D
 
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