PCB Stencil cutting laser

[dboe]

I am working on a stencil cutter and was looking at these two lasers:

- 2W 445nm M140 Blue Laser Diode in Copper Module W/Leads & 405-G-2 Lens
or
- Nichia NDB7875 445nm 9mm Laser Diode In a Copper Module With Leads & Glass Lens

Both or the same price. The first has G2 Lenses and the second is more powerful.

Which one would work best?

Here is the link to cutting stencils: http://hardwarebreakout.com/2013/03/...-pcb-stencils/

I am new at this so any help would be appreciated

Thanks
dboe

[swamidog]

either of those lasers will be more than powerful enough. the plans call for an LPC826 which is a red laser at 200-300mW.

I am working on a stencil cutter and was looking at these two lasers:

- 2W 445nm M140 Blue Laser Diode in Copper Module W/Leads & 405-G-2 Lens
or
- Nichia NDB7875 445nm 9mm Laser Diode In a Copper Module With Leads & Glass Lens

Both or the same price. The first has G2 Lenses and the second is more powerful.

Which one would work best?

Here is the link to cutting stencils: http://hardwarebreakout.com/2013/03/...-pcb-stencils/

I am new at this so any help would be appreciated

Thanks
dboe

[JJWMACHINECO]

Check out this thread and post 913.

http://hobbycncart.com/forum/63-151-46

This guy Mark claims he is getting a 405nm focused down to .0005" and using it to cut .032" Basswood. If that's true, that size beam could cut out some very fine detailed stencils probably fairly fast.

He said he got the LD and lens from DTR.

[swamidog]

that is beautiful. i'm definitely going to have to add a diode head for my co2 cnc rig.

Check out this thread and post 913.

http://hobbycncart.com/forum/63-151-46

This guy Mark claims he is getting a 405nm focused down to .0005" and using it to cut .032" Basswood. If that's true, that size beam could cut out some very fine detailed stencils probably fairly fast.

He said he got the LD and lens from DTR.

[dboe]

Awesome thanks all!

I was hoping to get some decent speed and finer cuts with a 2W unit.

dboe

[JJWMACHINECO]

The G2 lens DTR sells, will give you more burning power, but I found that this three element glass lens will give you a smaller/finer focusing spot.

http://www.ebay.com/itm/261245338420...84.m1439.l2649

There even better then the 3 element glass lens he sells. Sorry DTR, but a smaller burn line gives me more detail on my LD photo laser engravings. I am using two of the Nichia NDB7875 445nm 9mm Laser Diodes on my CNC engraver from DTR.

Jeff

[dboe]

JJWMACHINECO thanks for the update.

Which components did you get from DTR to fit the Nichia NDB7875 together with the ebay lenses or did you make the mounts yourself?

Thanks
dboe

[JJWMACHINECO]

I purchased the LD already pressed into the copper module with his 3 element glass lens. The one on eBay has the same 9X.5mm thread and will screw right in. The threads on DTR's module for the lens are a little loose and you will have to wrap some Teflon tape on the lens thread to tighten it up. I had to make my own heatsink for the modules to clamp into. I do recommend a Lasorb also because I have learned the hard way not using one. The Flexmod P3 is a good choice for a driver. That is what we use.

Jeff

[dboe]

Jeff

Sounds good. I will go that direction.

As far as the constant current supply I have some of these http://www.ebay.com/itm/171095601976...%3AMEBIDX%3AIT which are Digitally controlled constant current supplies up to 3A with an output stability of 5mv at 1 amp as measured on my scope. I would add a Lasorb ESD L44-47-121-683-X to the laser diode.

See any issue there?

Thanks
Dave

[JJWMACHINECO]

Dave,

I know that is reasonably priced, but looks like it was designed for a LED. I sure would not take a chance on something that may turn your $100 Laser Diode into an very expensive LED. The Flexmod P3 is designed specifically to drive laser diodes up to 4a, but still maintain the 3.7-5.5v it requires with a 5v-24v supply powering it. The P3 also will allow you to set threshold and max amps to your LD and with the analog modulation input, you can change the power of the laser diode on the fly by varying that modulation input voltage from 0-5V analog.

Maybe someone else on this forum has used one of those to drive a LD and can step in with some information, but I would not recommend using it.

Also DTR stated to me that the Nichia can handle 2.1a max, but I figured out by one of them failing, don't push them that hard for long periods of time. I changed mine back to 1.7-1.8a because in my application, they run for hours non stop in just one engraving.

Jeff