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Will these parts work?

LazNC

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I'm trying to build a laser module for a CNC machine. I've decided a diode based laser would be better to start with.

DTR seems to have a good selection and tons of options. I was thinking i could just get the NDB7875 with copper module, G2 lens, and SXD Driver.

Is there any issues i might have with these? I would like to control the SXD Driver with a variable PWM signal (not just On/Off TTL). I've seen tutorials that show some soldering can add PWM support to the SXD by simply removing a capacitor and adding a wire.

:thinking: Does DTR ship this assembled? (laser, module, driver + copper)
:thinking: Would this be a difficult mod once assembled?
:thinking: Is the SXD's modulation safe for this diode?

My reasoning for the laser is i want more power so that i can have higher feedrates.
The NDB7875 appears to be a good balance of power and divergence for my application.
The NUBM44 seems to have issues in cnc applications due to its wide "dot". I cant believe there's no optics that can correct for this, but there doesnt appear to be any readily available solutions. Are there?
The M140's are a good option as well, but i'd rather get the higher-rated diode and underdrive it, instead of pushing a lower-rated diode to its limit.


Or would i be better off leaving out the driver and getting this driver from x-wossee? (there is only one left so likely someone here will snatch it up lol)
3A analog linear / PWM laser diode driver with thermal protection | eBay

If these drivers are not suitable for this laser using PWM, what would be a good relatively cheap driver, preferably one i dont have to build. I've fiddled with electronics and have a basic understanding, but i dont want to put my $200 diode's life on the line, unless the instructions are real clear and easy.

I intend to use computer ATX PSU as a power supply (5v or 12v) but i've got a boost/buck converter i could use to tune the voltage further.
:thinking: This wouldn't be run off a battery. Would that change which drivers i can use?

Finally, i would love to get some protective sheets that i could mount around the laser head to help protect against the reflection/scatter from the work surface. Im aware thats not sufficient and will need 445nm goggles as well, but it would be a nice addition in case someone walks into the room unexpectedly. I couldnt find anything like this on survivallaser's site. If anyone knows of a good source of this material i'd be interested.


Optimally, i'd like to order the module from DTR if the SXD driver is easily modded for pwm.

I really appreciate any help i can get. Thanks!
 
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Encap

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Pretty clear you don't know enough--how can you expect good result unless you know what you are doing?

--it says right on DTR's Super X drive web page "PWN/TTL Modulation Frequency: Up to 1kHz. Modulation Voltage 0-5V Full range: 1.6V ON "Max 12V" & 0.6V - 0V OFF/

DTR modules with diode, lens, driver, and module are all assembled and ready to power up if ordered that way.
Email DTR with any questions--ask him what is best for your application. You will need to mount it in something and use appropriate lens and need a way to cool it to avoid thermal runaway and damage to the diode---ask DTR how long you can run a module as is by itself if you are thinking to do that

Did you study the DTR page Laser CNC Engraving https://sites.google.com/site/dtrlpf/home/laser-cnc-engraving

YOu can also use the LPF Search function at the bottom of the page --there are a lot of threads about CNC and engraving w. lasers

Look at Opt laser --they make and sell good quality low cost CNC and engraving heads---they all us NUBM44 diodes 000they have all the optics to make your own also
See: https://optlasers.com/en/34-engraving-laser-heads
 
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LazNC

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I dont think im that far off :p

I did read the SXD page on DTR's site. Thats where i found the PWM mod instructions:
https://sites.google.com/site/dtrlpf/home/laser-drivers/x-drive

To me this says it would work? The driver can handle the diode's requirements, and would provide PWM support once modified as per instructions. Is the assembled module easy to disassemble and modify? or should i order the driver seperate or ask DTR to leave it unassembled?
I believe "PWN/TTL" is a typo, and should be "PWM/TTL" and says "modulation voltage 0-5v full range" which leads me to believe its variable, not just on/off.
My control board supports PWM at around 900Hz.

Indeed it will be mounted on a giant aluminum faceplate, which should provide more than enough heatsinking capacity. In addition i have 12v computer fan and a large heatsync i can bore out to fit around it.
If heat is still too much of an issue i will simply dial down the power. i am not going to start dumping water over my electronics. This should be manageable though because ive seen others do it without water cooling.

As for the lens, DTR offers a G2 lens for it, which i believe is focusable. I shouldnt need any additional optics, as i can just set the G2 lens and use Z axis movement to maintain focus. Or am i missing something here? Im aware the "beam" isnt really straight and has a "waste" that is the optimal point of focus. This should be manageable with the G2 lens and Z axis up/down motion
 
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hakzaw1

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Pretty clear you don't know enough--how can you expect good result unless you know what you are doing?

--it says right on DTR's Super X drive web page "PWN/TTL Modulation Frequency: Up to 1kHz. Modulation Voltage 0-5V Full range: 1.6V ON "Max 12V" & 0.6V - 0V OFF/

DTR modules with diode, lens, driver, and module are all assembled and ready to power up. Email DTR with any questions--ask him what is best for your application. You will need to mount it in something and use appropriate lens and need a way to cool it to avoid thermal runaway and damage to the diode---ask DTR how long you can run a module as is by itself if you are thinking to do that

Did you study the DTR page Laser CNC Engraving https://sites.google.com/site/dtrlpf/home/laser-cnc-engraving

YOu can also use the LPF Search function at the bottom of the page --there are a lot of threads about CNC and engraving w. lasers

Look at Opt laser --they make and sell good quality low cost CNC and engraving heads---they all us NUBM44 diodes 000they have all the optics to make your own also
See: https://optlasers.com/en/34-engraving-laser-heads

QUOTING BECAUSE the OP may need to read this GREAT advice another time...at least.

and there are CNC forums as well. So theres that.
 
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LazNC

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err, could you point out what i've got wrong? thats why i posted this, hoping people would point out anything im missing. just saying "you're wrong" doesnt show me where im wrong.

If you're saying the driver's TTL isnt compatible, then would the one from x-wozzee work? The x-wossee driver was recommended on DTR's Laser Drivers page specifically for its modulation capabilities:
https://sites.google.com/site/dtrlpf/home/laser-drivers

I figured it would be more appropriate to ask these questions on a laser forum rather than CNC forums because, other than the driver having a PWM requirement, this is all laser-related electronics. CNC people mostly work with spindles
 
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hakzaw1

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about altering a TTL driver to become analog??? news to me.
but what do I know.??
.I buy TTL for on/off only and analog for full color... simple..
Have you looked into the CNC forums much??
Some of our members are there as well.. like 'Things' who is inactive ATM..here at LPF
 
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LazNC

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okay so the SDX is on/off only. tbh im not entirely sure how PWM and TTL differ other than i know TTL causes the diode to be fully on or off.

So would the Simpledrive v2500 work? it says it does both TTL and PWM:
"Linear analog, logic (CMOS or TTL - logic0 should be pulled to Gnd and logic1 should be pulled to 5V) or PWM modulation"
"Modulation input 0 ... 5V (analog)"
"Compatible with 5V Arduino PWM, e.t.c."

theres also the BlackBuck 8M here:
http://www.ebay.com/itm/BlackBuck-8M-8A-Buck-Laser-Driver-NDB7A75-NUBM44-NUMB05-NUBM06-NUBM08-/182404712160?hash=item2a782b06e0:g:ELIAAOSwjDZYZmhV
it says:
"Can be controlled/modulated by an external sources like DAC, PWM or analog modulated signal."


which is sold in DTR's shop, but why doesnt DTR offer it included in the module? Would that be because of its likely heatsink needs? size? or ... is this entirely the wrong driver/thing im looking for again? lol

I apologize if im asking really bad questions. i am trying to understand how to rig a laser to this machine. If you think i should try another forum, i appreciate your patience.
 
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