Large Scale Central

Laser Cutter Install Log

Modeling Technical Modeling
#61

Yep, they sent me 50hz / 240v. And a US seller! I sent them a fat not-happy-gram, and they fully refunded me. The new one (NOT from that first dope) seems to be running fine.

By “running fine” I mean on 110vac / 60hz (which it’s labeled for), and with the outlet plumbed right back to the inlet. The chiller has a 9L internal reservoir, but I was expecting to have a tub of water (like I’ve seen in many installations, where they are using a pump, not a chiller).

So I set it up like that, with the chiller reservoir filled, its outlet hose dumping into the half-full tub, and the inlet hose drawing from the tub. But after switching it on, the chiller just emptied its internal reservoir, and didn’t suck water any back in. So it seems like it’s designed for a closed-loop system, not open with an external reservoir.

Once I connected the outlet to the inlet, it ran fine, chilling the water from 25c to 22c. So the question I asked the vendor is whether this is the intended setup, or is their an inlet pump that’s not working.

This “chiller” doesn’t use refrigeration, only a fan and radiator I think. Also, there’s no setpoint adjustment; it’s meant for a 60-80W laser, and I guess you turn it on and hope for the best. But I asked the vendor about setting the temp as well.

I’d like to add a temp probe & meter, also an ammeter, per the advice of Dave Bodnar & others.

#62

I should have mentioned earlier that I received a lot of help with laser questions on this thread:

http://www.largescalecentral.com/forums/topic/26476/laser-cutter-questions

#63

Dennis Rayon said:

Cliff

Are you saying they sent you a 50 cycle/Hertz unit? If so, was that a “What we have here, is a failure to communicate”. That little Chinese person did not get the memo all US imports are 60 HERTZ

Dennis

Dennis, then you would get a bang out of HP. When I unpack one of their wide format printers, I find 4 different AC line cords in the box. Each one is for a different type of outlet. One I recognize as French, and one as British, and of course the USA one. The fourth I do not know. The printers are equipped with a power supply that can take 120-240 volts, 50 to 60 cycles, and convert it to the appropriate DC voltages the unit needs.

#64

In my previous “laser cutter questions” thread, Dave Bodnar mentioned he got a 50ma meter for his laser. Dave, I’m trying to figure out what I need, and have a few questions if you don’t mind.

DC, correct? Does this look ok?
https://www.amazon.com/dp/B008OUGWNW

Do I need to spec it for the 2kv or more voltage involved? And should I avoid the digital voltmeter-ammeter combo units (which have a max voltage much lower than that)?

Finally, where did you tie it in, and with what size wire?

Thanks very much,

Cliff

#65

David M., what was weird about my first chiller is that in only had a US-style 120v (not even 240v) cord, yet specifically cited 50hz 240v as the only power it could take. Bizarre!

#66

Looking at the power issues. Here’s the rundown of consumers, all on a 20A circuit which isn’t being used by much else.

Laser tube, calc’d (60w @ 110v): 0.55A

Laser machine (measured; no tube on): 0.6A

Fan (measured; labeled for 5A): 8.3

Chiller (as labeled) 0.9

Air compressor (measured) 2.3

Total 12.6

I don’t like how the fan is pulling 66% more power than its label says. Any thoughts on that, or running that total on a 20A circuit?

#67

I found out today that the small air compressor that came with the laser is hideously loud. I might take it off the list, and snake a hose from a remote (and quiet) compressor on a different circuit. The disadvantage with that is not having any clear indication that the air is on when running the machine, and sharing the compressor with different purposes (and pressure settings).

The supplied compressor specs are:

  • .035MPa / 5.1 PSI

  • 70 LPM / 2.47 CFM

To approaches come to mind.

Plan A: Use the compressor that came with the unit

  • Put it in the box with the fan
  • Plumb its inlet to somewhere else
  • Power it from the came line, switched from the same switch
  • Run a reinforced hose through the window with the duct port

Problem with that: it’s a sucky compressor, and I don’t know if it will have enough pressure with that setup.

Plan B: Use the quiet / remote compressor

  • Different circuit
  • Add a second port on the compressor
  • Run a pressure hose from that to the laser
  • Install a regulator & gauge at the laser
  • Maybe add a pressure switch, outputted to an indicator showing if air is on

Ideas / comments?

[edit]

After thinking it over more, to heck with both those plans. Dave M, I agree, too much hassle. I’ll find some way to quiet the compressor that came with it, and park it next to the cutter like I’m supposed to.

#68

Gee, this machine is starting to appear to be more trouble then its worth.

#69

It is not all that big a deal, David - I had both of mine working within an hour or two of delivery - it is all about how much time you want to put into preparation

dave

#70

Cliff Jennings said:

After thinking it over more, to heck with both those plans. Dave M, I agree, too much hassle. I’ll find some way to quiet the compressor that came with it, and park it next to the cutter like I’m supposed to.

Cliff - try hanging the compressor from one or two bungee cords - makes a world of difference when no vibration is transferred.

dave

#71

Cliff Jennings said:

Yep, they sent me 50hz / 240v. And a US seller! I sent them a fat not-happy-gram, and they fully refunded me. The new one (NOT from that first dope) seems to be running fine.

By “running fine” I mean on 110vac / 60hz (which it’s labeled for), and with the outlet plumbed right back to the inlet. The chiller has a 9L internal reservoir, but I was expecting to have a tub of water (like I’ve seen in many installations, where they are using a pump, not a chiller).

So I set it up like that, with the chiller reservoir filled, its outlet hose dumping into the half-full tub, and the inlet hose drawing from the tub. But after switching it on, the chiller just emptied its internal reservoir, and didn’t suck water any back in. So it seems like it’s designed for a closed-loop system, not open with an external reservoir.

Once I connected the outlet to the inlet, it ran fine, chilling the water from 25c to 22c. So the question I asked the vendor is whether this is the intended setup, or is their an inlet pump that’s not working.

This “chiller” doesn’t use refrigeration, only a fan and radiator I think. Also, there’s no setpoint adjustment; it’s meant for a 60-80W laser, and I guess you turn it on and hope for the best. But I asked the vendor about setting the temp as well.

I’d like to add a temp probe & meter, also an ammeter, per the advice of Dave Bodnar & others.

Cliff, Your unit like most has an internal pump and sump. The pumps suction inlet port is coupled to an outlet on the bottom of the tank. The pumps discharge port pushes water to the laser via the “outlet” port, warmed water returns from the laser to the air over cooiling coil where its cooled and returned to the TOP of the sump with an air gap in play.

Many of these “water chillers” are just air over finned cooling coils. Works like your cars radiator. I noted many refer to theses water chillers as employing “Thermolysis” which IMO is a sales gimmick, whereas Thermolysis = heat dissapation. Yet the term is more akin to the evaporative process atypical of evaporative water coolers and or water cooling towers again IMO. I work with build, design and install water cooling systems, mostly refrigerated systems plumbed simarly to your unit with a heat excahnger, cold plate or evaporative cooling coil in lieu of the air over cooling coil.

What temperature(s) are you wanting to monitor?

Ammeter is for measuring laser current?

Michael

#72

Cliff Jennings said:

Looking at the power issues. Here’s the rundown of consumers, all on a 20A circuit which isn’t being used by much else.

Laser tube, calc’d (60w @ 110v): 0.55A

Laser machine (measured; no tube on): 0.6A

Fan (measured; labeled for 5A): 8.3

Chiller (as labeled) 0.9

Air compressor (measured) 2.3

Total 12.6

I don’t like how the fan is pulling 66% more power than its label says. Any thoughts on that, or running that total on a 20A circuit?

Did you include the current used when the X and Y axis are moving via stepper motors in the 0.6 A or is that just at “idle?”

#73

Cliff - on the cooling I use a covered container that has 3 gallons of distilled H2O in it - I have two temperature probes that I hooked up to an Arduino - one measures the temperature coming from the reservoir and the other the temperature of the return H2O.

I keep an eye on it and, if it gets much above ambient, I toss a frozen bottle of water (ice!) in the bucket to keep it cool. Only need to do that on long projects.

dave

#74

Cliff - the 20ma meter goes in the return line from the laser and shows the power going to the laser tube.

I would recommend viewing this video that goes into detail about hooking it up - the fellow has done about 100 videos on using these lasers and really knows his stuff! I have learned a lot.

video: https://www.youtube.com/watch?v=xDZmuxq5BEM

You may also want to download and peruse the index to his first 72 videos - It can be seen here:

http://trainelectronics.com/LaserEngraver/rdworks%20learning%20lab%20index%20(to72).pdf

dave

#75

David Bodnar said:

Cliff Jennings said:

After thinking it over more, to heck with both those plans. Dave M, I agree, too much hassle. I’ll find some way to quiet the compressor that came with it, and park it next to the cutter like I’m supposed to.

Cliff - try hanging the compressor from one or two bungee cords - makes a world of difference when no vibration is transferred.

dave

Dave, good call, but when I just held it in my hand it was still pretty dang loud. So I’ll call that my backup plan if my current approach doesn’t work out. That approach is to mount the compressor (which is basically an oversized aquarium pump I think, just really loud) in a foam-lined ammo box.

The obvious problem here is heat buildup. So I’m running it now, and will take temp readings at a half hour and an hour. If it’s real hot, I’ll have to do something else.

[edit, 3/26] With everything running, and since the dB isn’t any higher with the lid off this box, I’ve taken the lid off permanently for better cooling. The foam is still on the sides though, because it helps as a vibration isolation mount.

#76

Michael Glavin said:

Cliff, Your unit like most has an internal pump and sump. The pumps suction inlet port is coupled to an outlet on the bottom of the tank. The pumps discharge port pushes water to the laser via the “outlet” port, warmed water returns from the laser to the air over cooiling coil where its cooled and returned to the TOP of the sump with an air gap in play.

Many of these “water chillers” are just air over finned cooling coils. Works like your cars radiator. I noted many refer to theses water chillers as employing “Thermolysis” which IMO is a sales gimmick, whereas Thermolysis = heat dissapation. Yet the term is more akin to the evaporative process atypical of evaporative water coolers and or water cooling towers again IMO. I work with build, design and install water cooling systems, mostly refrigerated systems plumbed simarly to your unit with a heat excahnger, cold plate or evaporative cooling coil in lieu of the air over cooling coil.

What temperature(s) are you wanting to monitor?

Ammeter is for measuring laser current?

Michael

Thanks Michael, that’s exactly how it’s acting. It has the 9L internal reservoir, and the water is getting pumped from there, and out of the outlet (vs. suction-pumped into the inlet). So it sounds like to affirm that it needs a closed circuit to work, because that’s the only way the water is going to get pushed back into the chiller.

I’ve been confusing myself, because the laser system comes with a (suction) pump which requires an external reservoir. But since I’ve gotten the impression that a “chiller” is a better approach, I got one that declared its compatibility with a laser system like this. So I was expecting that an external reservoir was also needed with that. But after seeing how it works, hearing what you say, and reading between the chinglish lines in the “manual,” it all seems like the external reservoir is NOT supposed to be involved with a chiller having its own internal one.

Thanks for helping me think this through.

The temp probe is to monitor the water temperature. But now, since the chiller has a temp readout, I’m not sure what the point would be in having an additional one – except to have it up at eye level, near the main control panel. Hmm. So I may bag that.

The ammeter, as I understand, is very important. The laser tubes are not really rated for what their power supplies put out – over the long term.

#77

Todd Brody said:

Did you include the current used when the X and Y axis are moving via stepper motors in the 0.6 A or is that just at “idle?”

Hi Todd, no, I haven’t yet. Good point. I expect those to draw less than an amp, but still it should be factored in.

#78

David Bodnar said:

Cliff - on the cooling I use a covered container that has 3 gallons of distilled H2O in it - I have two temperature probes that I hooked up to an Arduino - one measures the temperature coming from the reservoir and the other the temperature of the return H2O.

I keep an eye on it and, if it gets much above ambient, I toss a frozen bottle of water (ice!) in the bucket to keep it cool. Only need to do that on long projects.

dave

Interesting. If I were to do the same, it would have to involve in-line probes in the hoses between laser & chiller, since I have no external reservoir.

There is an alarm function on the chiller, and it will go off if the temp goes above 60 deg C. But that’s 140 deg F, much higher than ambient! I’ve asked the chiller vendor to splain how to adjust the set point, but I fear there’s no adjustment.

I can’t find yet what temps the tube will tolerate. Have you seen info in that regard?

#79

David Bodnar said:

Cliff - the 20ma meter goes in the return line from the laser and shows the power going to the laser tube.

I would recommend viewing this video that goes into detail about hooking it up - the fellow has done about 100 videos on using these lasers and really knows his stuff! I have learned a lot.

video: https://www.youtube.com/watch?v=xDZmuxq5BEM

You may also want to download and peruse the index to his first 72 videos - It can be seen here:

http://trainelectronics.com/LaserEngraver/rdworks%20learning%20lab%20index%20(to72).pdf

dave

Thanks Dave, yes this is the guy that was so informative on the 40W system, I watched all his videos. But I didn’t realize he’d made a new set on the larger units. So I’ll start watching!

#80

About the foam-filled compressor case.

After a half hour of running with foam packing, the temp on the compressor body was 140 deg F. After running a half hour more without foam packing, the temp was 130 deg. F.

So since it just runs that hot, perhaps the extra 10 deg F isn’t that big a deal…

Because this is such a cheap compressor unit, I’m considering letting it run in the foam-filled box. And when it fails, put in something better & quieter. But not before then.