Have a few shopping carts filled up.....CO2 laser upgrade - couple quick questions

The biggest question I have is whether I can run the 40w CO2 setup with the MiniRambo running the firmware I’m currently using for the 2.8.

Second question is dust management. Seeing all the mirrors and the lens setup I wonder if a chainsaw carver’s shop is perhaps not the best place for a laser set like this? Can anyone advise?

Lastly, should I/could I either design and print a mount to keep the 2.8 attached to the same gantry or am I better off maybe moving the 2.8 over to the other MPCNC (Rambo controlled, dual endstop)?

Appreciate anyone’s thoughts on the matter. I’ll wait until morning to hit “Proceed to Checkout”.

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Dust on the mirrors gets ugly when the laser fires. Usually it just burns off and ruins the mirror, but sometimes it gets hot enough to shatter the mirror, then you have a laser shooting somewhere it’s not supposed to.

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Mini Rambo will technically work, but expect a lot of pauses with high speed raster engraving, and I don’t know if even 2 nema 17s can move the gantry fast enough, which ones to my next point: motor sync.

If a motor on one side skips steps, loose pulley, motor unplugged, the laser can now be misaligned and that’s a big safety issue. I love the MPCNC, but it does not make a safe platform for a co2 laser.

MO mirrors would last the longest and need less cleaning but I recommend Si mirrors so you can squeeze every bit of power from it.

I’ll second this. I was looking at building a second MPCNC to put a co2 laser on and after much consideration and designing/though, decided against it.

The MPCNC would work well for a diode laser where you can mount it on the tool mount, but I wouldn’t use it for co2.

I keep hoping someone takes Jamie’s double decker design and just mounts the tube straight to the Z. Ironically a very rigid Z for a laser, but no alignment issues at all.

For the misalignment causing random burnings, could you build up sides like we’ve seen before and put some black spray painted steel or something on it? Something that will absorb, but not burn?

“Ow! My spleen!”

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I could see this going very very wrong if any of the steppers on the top gantry skip or fries a driver.

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Or the water coolant springs a leak

Why? It would just be pointing to the wrong place on the board. It won’t wildly fire lasers around the room. The laser also isntwthe structure between the two gantries, there are still pipes connecting them.

Water coolant wouldn’t be fun, but as long as your were there, you could shut it down and just have a big mess to clean up.

Did he use one long set of Z axis tubes connecting the two gantries?

I thought half the reason to go co2 was to sling the beam around really fast for engraving. I think you could go slow enough for through cutting, maybe.

So it won’t turn into a Stormtrooper?

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I am skeptical of that configuration being able to handle moving a 700-800mm long tube filled with water and 20,000 volts moving at 200-300mm/s.

At that point, a bed moving in x/y would be better, kind of like the laser babdsaw Jimmy diresta and FSL made.

I’ve got visions of one of those waving head guy inflatable things only it’s a glass tube flopping all over the place.

I’m going to go for it on the MPCNC but likely as a temporary measure. I’ll build up something more robust like a Y-1200 over the course of the summer and migrate things. I have an opportunity at my hands to offset the cost of the upgrade by more than half and trust my machine. In all the time I’ve been running the 2.8 I’ve only ever had issues caused by operator error (gcode for a bed bigger than I was running). Thank you for the words of caution though. Definitely appreciated.

He did connect them.

IDK. This is the devil I know at least. I am not sure you need to reach those speeds if you are through cutting. I am also not too worried about the water when a single gantry can easily hold a big router. Having twice the motors to sling it around could really make up for some of the troubles.

I guess if you’re willing to give up the real moneymaking part of the laser then sure, 1/8" ply or acrylic needs 10mm/s at 10-13 ma.

Despite my warnings, an extremely dangerous build is being recommended, so I will no longer participate here. Conjecture and theory is fine, but this too much. You could achieve a safer and cheaper build via vslot, and still achieve high speeds. Or even buy a k40 and tinker.

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If it’s in a enclosure how would it be any more dangerous than a k40?

I’ve looked at all of those options and agree - the 2040 vslot will be a great machine platform but in my case I’m not starting from scratch - I’ve already got a dedicated, enclosed, stainless tube MPCNC laser running (IE: materials all paid for). In looking deeper at both the K40’s from China and the Y-1200 buildup I see just as many hazards. I most certainly will not be strapping a tube to the gantry - I’ll use the mirror setups. And I’ll keep things clean by sealing the enclosure, filtering incoming air so the smoke and bad stuff can vent outside as the 2.8w currently does. And clean before every run.

I have seen steppers skip (completely disable in fact) and have seen how much the x or y rails can deflect and I question whether they would deflect enough to send a stray beam across the shop…still not a hazard to ignore (and mitigated by the enclosure which in the case of a K40 is a in box) but I don’t think it’s as grave as the above posts might make it seem. I am definitely going to look into this though and see just how much deflection I can get out of my rails. It’d a valid concern. Just might be a non-issue. My machine is pretty rigid.

I appreciate your seriousness and share the same seriousness.