Upgraded the 'Puffy" little Air Assist... to a 'Puffier' little Air Assist

So an interesting thread here on Lightburn caused me to consider installing a Gas Air Flow Meter on my CO2 laser. For those times when you still want a little positive pressure in the lens and nozzle, to keep out the smoke and debris, but you don’t need the full on air flow that the factory pump provides.

Now I say that, knowing that there are others out there with 50 gallon tanks and multi cylinder compressors that are putting out a bazillion PSI and doing as much cutting with their air pressure as they are doing with their actual laser beam. Ok, perhaps a little exaggeration. But you know who you are.

When I bought my 60W laser, it was with the intention of doing more engraving than cutting, so I spared the 150W tube and stayed small. I also don’t need a ton of Air Assault, just a little Air Assist to keep the flames at bay, and the soot to a minimum. Anyway, the included air pump was of the 30 Liter per minute, 16 watt variety and seemed to put out a reasonable puff. Much better than the diaphragm type pump of my old K40 and much, much quieter. After installing the Air Flow meter, I found that the typical 30L/min pump was only seeing about 12-14L/min after travelling through my systems hoses and reaching the nozzle exit (about 17L/min if unrestricted).

So I thought, what if there was another diaphragm pump out there with a little better flow? I found a 25 watt, 54L/min pump on AliExpress and ordered that up. When it got here I was a little disappointed because although it said 25 watts on it, it also said 30L/min, just like my old pump (even though their listing said it would put out 54L/min - so it’s being returned as we speak). But then I stumbled across an Ortur air pump that again claimed 50L/min, so I ordered up one of those. It arrived tonight, and I installed it immediately… it was a bit better, but not the 60% improvement that I was expecting.

Anyway, here are some results…

The original Aqua Blue 30L pump:

Its output:

Video of output (using the highly scientific water wobble test):

The Ortur 50L pump:

Its output:

Video of output (also using the highly scientific water wobble test):

That Ortur pump is built like a tank, and for $104, it’s very quiet, and I may keep it as my main pump and keep the original 30L/min pump as a backup.

I doubt I’ll ever need anything more than this in my 60W laser, but if I ever purchase a 150W cutting beast… then I’ll put that one in the shop and tie it into my shop compressor, since it’s never going to fit in my upstairs spare bedroom where the 60W resides.

Just thought I’d share the info here on the Lightburn Forum. Oh yeah… it was the Geek in me that decided to stick a single LED in the bottom of the Air Meter.

Air Meter Link.
Ortur 50L pump link.



Nice info. Suitable solution for most, I think.

How are you driving that LED? I like the idea and will be stealing it.

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I just tied it into the 24v that runs the rest of the internal lights on my laser. I drilled a hole in the bottom of the Acrylic and ran the wires through the chassis to the inside. It’s a 12V LED, but I ran it up past 24v on the bench power supply with no troubles, so far, so good. Not to mention I got 50 of them for $12 on Amazon. Decided to stick with white.

Sweet! Thanks for the link. I’m running at 24v, too. I assumed I would need a buck converter or resistor to tie a single diode into my pump circuit.

Well, I’m not saying I did the right thing here… but I did run this LED up past 24v on the bench and didn’t fry it, so I assume there is some safety margin built into these bulbs.

Which agrees with the results in my laser with similar plumbing, suggesting the 6 mm tubing + fittings betwixt pump and nozzle really is the limiting factor, not the pump’s alleged rating.

Now we know!

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“betwixt” Love that.
Just love that.
Gotta work that in somewhere…
Betwixt… puts my original desire to use “Plethora” more often, into second place now.


Both flow meters show 15LPM flow rates. Is that what you settled on to “slightly pressurize” your nozzle. I think I will add a 10PSI gauge as well. I expect 2-3 PSI would be adequate.

What I need is a method to pause the run between engrave and burn because I am using a manual ball bleeder valve to switch. My cut is on a second layer.

The images of the flow meters are the same meter. I chose the 25L meter thinking that I might be able to achieve close to that with my 30L pump… but, naw, ain’t gonna happen. I was just expecting more performance when going from 30L to 50L but only saw an additional 2-3L/min. I can dial down to a lower rate when needed by turning the knob at the top… no different than others putting in valves to restrict the air. I’m not really sure what a good minimum would be, but yeah, just enough to keep smoke out of the nozzle, but not disturb say, powder coat paint, if one chooses to try that technique.

There are those who have installed dual solenoid air valves and other hardware that takes advantage of the ‘wind’ terminal on the ruida controllers. This allows them to turn on or off their solenoids based on the air toggle on each layer in Lightburn. Without this, I would assume you either need to be ready to turn your valve manually, or just run the job in two phases… low air, and no air. I just don’t need that much flexibility or control in what I do.

In my case, I want Low Air or Air Knife. I did one project with two layers and turned off the undesired one. Everything I do is one-off, so Mikey’s Layer Switch method works just fine.

When I buy the flow meter, mostly for show, I am going to buy (just decided while writing this) a digital air pressure gauge located between the nozzle and the flow meter. This will give me a safe upper pressure reading, but decent resolution when the bypass valve is open.

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Do come back and show us please.
(It’s my thread, and I can steer it anywhere I want :slight_smile:)


I too have stayed on the low side, My plasma cutter in the shop has a 5 hp 17cfm compressor feeding the torch, but I have just a 60 watt pump for my laser. It moves plenty of air to keep the cuts clean and is quiet as a churchmouse. It just seems silly to use more power in the air mover than in all the rest of the system (My 2 cents).

Laser and I will be separated for about a month, but I will share.

I too have a quiet (Sculpfun) pump. I have to reach down and touch it to make sure it is running.

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Noise = power. Ask any import tuner fanboi. :grin:

I killed my first compressors because they weren’t meant for the duty cycle. I’ve since switched to industrial aquarium pumps and couldn’t be happier. They’re super quiet, available on Amazon prime so a replacement is 24h away, and they go for under 100 USD! I don’t trust the specs in the least bit, so I went with trial and error and settled on this size. It’s more than enough to blow smoke and even wood dust from cutting stock to size.

EcoPlus 728457 1300 GPH https://www.amazon.ca/dp/B002JLGJVM?ref=ppx_pop_mob_ap_share

I had one that was smaller for a third of the price as well ZOIC Commercial Air Pump, 317 GPH… https://www.amazon.ca/dp/B01EJBOLGO?ref=ppx_pop_mob_ap_share
It was fine for wood, but not enough for flames from acrylic.

I have a hard time calling any of these units, ‘compressors’ as they neither compress, nor store compressed air onboard. They are definitely just air ‘pumps’ in my book.

I had a similar single diaphragm style like this on my K40 laser, it worked fine, but man, was it noisy compared to the style I have now. I mean, really, really louder. Even with the rubber feet… and I mounted mine hanging under the back side of my desk, suspended by the rubber feet… still really loud compared to this newer style.

My 30L/min equates to 480 GPH, and the 50L/min puts out 792 GPH. Both adequate for engraving and light material cutting.

And for the record, Noise = Obnoxious, to me.

Agreed on air pumps. Like my post said, I moved from compressor to pump. It’s funny how I find them so much quieter than my previous compressors! Lol… I’d definitely be happy to find something even quieter!

I also liked how small the pumps are.

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Loved this one!


So, how do I put this…
The difference between these two styles of pumps are…

Single Diaphragm, goes, “RRRRRRRRRRRRRRR”
Other style goes, “MMMMMMMMMMM”

How’s that?

Sweet. For research purposes, what are they called? Since you called the ones I posted single diaphragm, I’m guessing the super quiet ones you found aren’t?