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I found several used liquid cooled Coherent 35 watt Laser Diode types unde $200 each. 35 watts @ 830nm. Threshold laser @ approx. 18 amps. Would this be minimally acceptable to cut lightweight fabric at >= 5cm/s ?
While CO2 could be used it gets much more complex to design with several mirrors etc. I'd like a lightwieght laser that can move. Also these old lasers are no longer made at Coherent and I'm looking for a data sheet.

I would love one of those lasers. Let me know if I can get one somewhere.

35W should be plenty of power to cut fabric. I have not used the wavelength, but it probably works.

The buildlog 2.x cuts fabric just fine. Leaves a very nice (non charred) edge even with excessive power or insufficient speed.

I think the wavelength may be a factor, though: Your 830nm laser may behave very differently than the CO2 10600nm laser.

Yes ebay is a source. The 830 Nm diode is oblong and would require some odd optics but I suspect doable. I might just buy one and setup a single axis test jig just to test it with various fabrics under acceleration to determine what it can and cannot cut and how fast.
I also need to see how well aluminum patio screen will stand up under the fabric as an alternative to honeycomb (cost issues) as i need a vacuum exhaust table that will be fairly large (5' by 8'or 10' long. I'm also thinking that aluminum pool enclosure beams are plentiful in Florida and already have the welting slots for the screen if it will work without burning.
I think the CO2 1060Nm cuts metal better than the shorter wavelengths but am not sure. My intent is to keep the cutting speed above a limit where it damages the aluminum screen but cuts the fabric.
All feedback is much welcome!

I know which modules you are talking about and you are going to have a very hard time getting the beam shape to be useful. These would be good for side pumping a Nd based laser like a YAG or a Vandanate crystal.

Be very careful with these laser diodes at the shorter wavelength. Many things that appear to be opaque are transparent. A laser cutter built with these needs to be in a completely enclosed metal sided system. This wavelength will pass right through black acrylic. The reflections from this are just as dangerous and can cause retinal damage. Make sure you have good google rated for this wavelength.

In the end it would be best to spend the money and get a CO2 tube.

I'm on marcona's side here, mostly because from a safety perspective diodes in the near IR scare me.

You cannot see the light but unlike a CO2 laser the beam is not stopped by the outer layers of your eye. That means that any light you see (Even if you glimpse at the spot where cutting is occurring) will be focused by your eye into a tiny spot on your retina. This is compounded by the fact that you will be unaware damage is occurring so the protective reflexes will not kick in.

When a glimpse at the dot of the laser has the potential to permanently damage your eyes during things like initial set-up. At 35W even reflections of the beam are trouble. And of course, it becomes much harder to ensure safety when you cannot use regular glass or acrylic for protection.

Sure a CO2 laser is also dangerous, but at 40W you really need to stick your face in the beam. You don't get surprise invisible reflection blindness.