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First completed build! And a learning experience

Crackula

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Glad you got it focus, but you find out soon the focus ring is there to help protect your fingers from burning while focusing:)
Unless you have big fat fingers like mine. Nubm44 got me 🤕
 
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trephanation

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So I've been able to play around with the focus of the 2E-G for a bit, and I've found that it's a pretty decent burner. Not quite as good as my Chinese 450nm Amazon laser however, except the threading on the Amazon laser has unfortunately crapped out so I'm debating on building either a 405nm or 450nm next.

I know this is the Green section but does else think that a BDR-209 ran at 530mA would work well in a similar host, or should I go for a larger one with better heatsinking? I'm not sure if the shorter wavelength violet would cause the device to become hotter than my green one.
 

paul1598419

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All the 405nm diodes have a higher forward voltage than the blue ones. That means they run hotter. Also, they are very temperamental. They can fail at a moment's notice. Usually right at turn on. I was losing them left and right until I used a huge C11 heat sink and decreased the driver current. You might get away with 530 mA, but I would keep the drive current no higher than 500 mA. Because the BDR209 is a single mode diode they are great for burning, but are not that visible being so close to UV.
 

trephanation

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So if I were to run the BDR-209 at 445mA which is one of the fixed current options on SL, according to DTR's test page I would get around 740 milliwatts if I were to use a G-2 lens as well. Would this minimize potential loss of the diode as long as heatsinking is adequate, or do you think it would be more sustainable and better for a newbie to just get a robust multimode 445 diode to work with? I wasn't looking so much for visibility, but more for that incredible fluorescing effect that the 405 almost-UV wavelengths create when they come in contact with translucent materials, as well as for the burning power possible from such a short wavelength on a single mode beam.
 

GSS

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The best info I can give is I had this BDR-209 doing 700mW ish with a G2. It is in a small pen light host but using a 12mm Dtr copper module.
Yes it heats up somewhat quickly but iv'e had for a few years and maby 10 hours total with me etching popsicle sticks.
A C6 or 501B host should really be a good step up heatsink wise. Yes I would limit it around 700mW.
 

trephanation

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The best info I can give is I had this BDR-209 doing 700mW ish with a G2. It is in a small pen light host but using a 12mm Dtr copper module.
Yes it heats up somewhat quickly but iv'e had for a few years and maby 10 hours total with me etching popsicle sticks.
A C6 or 501B host should really be a good step up heatsink wise. Yes I would limit it around 700mW.
Interesting, do you think the extra 40 mW will make much of a difference? I was just going by the fixed 445mA current buck drivers available from SL which are probably the most convenient to set up. I've messaged Lifetime about some heat sinks as well, the ones he has look like they would be a great fit for this build I have in mind.
 

GSS

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I'm the worst to ask but I wouldn't think 40mW more would be a issue.
It's when they are pushed to over 800 to 900mW's I see membera claim failure but like some posted alot is on start up also..
Yes Rich will make a nice for sure.
 

paul1598419

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Even at 400 mA these diodes are still being seriously over-driven. They are temperamental diodes and they fail the harder you push them and the less heat sinking you use. I have told you what has helped with my 405nm diode builds. At least they aren't expensive diodes, so if you have to replace a few they won't cost you at lot of money. A 2+ watt M140 445nm build is also a good burner. They hold up a lot better too.
 

trephanation

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Even at 400 mA these diodes are still being seriously over-driven. They are temperamental diodes and they fail the harder you push them and the less heat sinking you use. I have told you what has helped with my 405nm diode builds. At least they aren't expensive diodes, so if you have to replace a few they won't cost you at lot of money. A 2+ watt M140 445nm build is also a good burner. They hold up a lot better too.
Thanks for the info! What about an Osram PLTB450B, as it's readily available in module from DTR. It looks like 1.8A will reach 2.1W but I'm not sure if that's overdriving the diode too much and 1.5A would be safer for that.

Also let me know if I should make a different thread for these questions, I know we're way off topic from Greens now, lol.
 

paul1598419

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The PLTB450B is a good choice. These blue diodes aren't as touchy as the 405nm ones are. You can start a new thread if you expect to have many more questions. But, just get Jordan, DTR, to set it up for you and put it into a substantial host and you're done.
 

GSS

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Thanks for the info! What about an Osram PLTB450B, as it's readily available in module from DTR. It looks like 1.8A will reach 2.1W but I'm not sure if that's overdriving the diode too much and 1.5A would be safer for that.

Also let me know if I should make a different thread for these questions, I know we're way off topic from Greens now, lol.
Yes that PLTB450B1 is a good one. Iv'e had one going on 4 or 5 years in a 501B host set at 1.8A.
It even has a bit better tighter beam and spot profile than a M140. I'm using a G2 lens and don't see the need to tame it with another lens..
 
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Lifetime17

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Hi,
The PLTB450B diode is an icon of diodes , its been around for years and is very efficient . it will hold up to 1.8a no problem with good heat sinking. As Paul said it has a better divergence than the M140 but the M140 is a great diode also
As for the BDR-209/405nm diodes keep them set lower they are very fussy critters to failure at higher settings. Even at a 600mW output they are real burners due to the fine divergence of the beam.
Every one here gave outstanding help keep that in mind for reference. these guys been building for ages.
Rich:)
 

GSS

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Rich it's funny as my pen hosted 405 and 501B purple colored host with the PLTB450B1 is from you:);)
 

Lifetime17

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Hi GSS,
Glad to hear that they ar still going strong buddy, Yes it was I coincidence that this came up good call...
The PLTB450B diodes ae worth the cash and not to leave out the M140's.
Rich:)
 




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