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GSS

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Yea, I make heat sinks and some MacGyver builds, I like to do as much as I can with limited tools but I still don't have a lathe or a mill and some times I need better tolorances so I am having parts made by Rich and Tung which is a great help, I really want to do some double 44's and double 7A75's c-lens corrected and with beam expanders but I am waiting for optical parts from Poland.

I am waiting for my rotators from OPT in Poland, it's been 4 weeks, has anyone ordered from them ? How long does shipping usually take ?
131.00 for two little pieces of glass but I need them to build a couple of dual nubm44 with 6X correction and beam expanders, should be real fun fire makers but I still wish every day for some bigger visible laser diodes, I may have to build out some of my ir projects, but I really prefer visible beams.
I had a gut feeling you were putting something together for me, I was thinking a drawing or maby a schematic or something?? not a video though:whistle:😁
You mentioned and showed 2 100W 2 ohm resistors. I'll probably order some from China and wait the course.. How much doe's the Ohms rating matter? They seems to have some 5 100W from 1, 2, 3, 4, 5ohms to choose from.

As far as your OPT laser question, we usually come to you for these answers:LOL:
 



RedCowboy

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Ohms are a measure of resistance, the higher the resistance the less current will flow.
At 4 volts through 1 ohm 4 amps can flow but at 4 volts through 10 ohms only 400ma ( 4/10 of an amp ) can flow.
So a 1 ohm resistive load is a reasonable test, for example a nubm44 with 2 x 18650 in series using a 4.5a sxd driver will draw 3 amps at 8 volts so each cell is putting out 3 amps at 4 volts, ( 12 watts each cell ) so the 1 ohm resistor is a reasonable size for a quick battery sag test.

The wattage rating of the resistor is what it can take, but as we are turning battery power into heat a bigger ( wattage rating ) is better, if you used a small 1/4 watt 1 ohm resistor the IMR cell would burn it up, but the 100w 1 ohm resistor just heats up.
 
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GSS

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Red, i'm due today for a couple of those resistors you linked..:) "and a LPM";) from some great member's.
Anyway's I was looking for 18350 battery cradles but they only seem to come in 18650's and even if I mickey'd them to fit a single 18350, from what iv'e red the wires they come with are way undersized and the battery springs are to thin and will glow red and end melting the plastic..
Just double checking, as it looks like you used some good size copper transformer winding wire attached to the + and - of the DMM and bent to fit the battery of your load testing??
 

RedCowboy

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I just bent some 12ga solid copper wire such as what runs around in our homes walls inside that Romex wire.

You can make your own or buy something like this if you want >



I had bought some like this before but am not seeing them on ebay >

 
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Pelagius

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:)
No No Red, Pelagius is a member who happened to buy a Phaser from me.. It was directed at me for getting somewhat ripped off..

Pelagius, by the way nice to see you still lurk the forums:)
Hi! I do Lurk- much like the Creature from the Black Lagoon! :) I've been focusing on my other hobbies-one being 3D rendering-mostly Star Wars related these days. :) My neighbor got suckered into a THREE THOUSAND MEGAWATT Death Star Laser-on Facebook- was shipped a "Laser 303" Green-for HALF OFF- at $50.00. I showed him some of my Sanwu's- and he particularly LOVES the Phaser I bought from you.
I UNMERCIFULLY deluged him in safety lectures and sent him here. I also sent him a link to your Star Trek Beyond (Darkness?) build on EBAY.
 
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GSS

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Red I keep forgetting that you always add more;) through edits, but I usually go back and re re re re read your posts:)
The last holders you added I did see them on ebay or Amazon at one point and could not find them again..
They were up there in pricing "compared to cheapie holders" but if they are as heavy duty as claimed then they are worth it.. Only problem is this sight looks alike a bulk wholesaler??
 

GSS

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Ok Red did some load tests with the one 100W 1ohm resistor..
These were on 18350 and some 16430 cell's so far and quite shocking just how bad cheap cells are..
Efest 18350's at about 4.1V dropped to 3.7V and 3.6V, purple cells and red cells in that order and stayed stable even after maby a full minute or more..
Surprisingly the 18350 AW didn't do as well at 3.5V but was only at 4V from the start..

The cheap red GTL 16340's went from 4V to a 2.2V and the blue 16340 ultrafires dropped from 4.15V to a ridicules 1.8V!!:LOL:
The blue 14500 ultrafires dropped to a pathetic 0.78V!! Are they KIDDING meo_O
The 18350 re raps that brought up this thread did a ok 3.3V+ considering I have no clue what cells were they were before the re rap??
 
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