Can I Cut Through 1/4" Thick Baltic Birch with a 30-Watt Laser Cutter?

[Bert Kemp]

I just got finished cutting 1/4" BB .......60 watt laser 2 passes 75% pwr 20 mmps yes slow but wanted to make sure it got thru on 2 LOL. I could go more pwr and slower for 1 pass but the edges turn charcoal.

[Scott Memmer]

Hey, Everyone. I promised myself I would report back after I cut the Baltic Birch, as a reference for others. Thanks again for all your input.

In short, my little 30-watt Epilog Zing laser cut through both the 1/8" and 1/4" BB like buttah. It confirmed my suspicion that Epilog underrates the power output on their machines, as I believe most of the more reputable companies do.

Specifically, I cut the 1/8" BB at the following settings -- Speed 20%, Power 75%, Freq 500. It cut through beautifully on the first pass, clean through the material, and the char was totally acceptable for my purposes. In fact I could easily have backed this off to, I suspect, maybe 25% Speed, 50% Power, and the same Freq. If you're working with this same material and concerned about cosmetics, the char was pretty black on my cut, so the Epilog appeared to have enough juice that it can be backed off to reduce that charring.

On the 1/4" BB the results were equally impressive. I ran it at Speed 10%, Power 80% and Freq 700 and, once again, it cut all the way through on the first pass. Again, pretty black char, but I'm using this material for a jig/work-holding application in my shop, so cosmetics are not an issue. The char was NOT such that it affected the structural integrity of the wood, just mainly a blackened color. I had a sense that, even with the 1/4" thick BB, I could have backed off further to maybe 15%, 70%, and 700 and it still would have cut all the way through.

BTW, Epilog appears to be dumping the Zing laser series. They've got them marked down by about 30% on their site. I've been suspecting this for more than a year. They will need to come out with entry-level machines with much more power, to compete with Dremel, Glowforge, etc. I anticipate an entry-level machine from Epilog in the 80-watt range for less than $10,000. We shall see.

Thanks Again for all your help,
Scott

[Kev Williams]

Sorry, but I'm curious as to why (it seems) many users never run at 100% power when cutting-? I can understand it with higher power machines, but running a 30 or 40 watt machine at 80% power- at slow speeds- seems counterproductive..

I ask because, whenever I CAN make use of 100% power, I DO...

just curious

[Lee DeRaud]

I ask because, whenever I CAN make use of 100% power, I DO...

True that, especially for my wimpy 25W(+?) machine, where the speed has to be slow even at 100%.

[Bert Kemp]

trying no to over drive tube no meter

[Scott Memmer]

Gents, on this last point: So, as a novice here, if you run at 100% does it reduce the life-expentage of the machine or the lenses (where they might need to replaced sooner if driven under max power)?

Thanks for clarifying.

sm

[Lee DeRaud]

Gents, on this last point: So, as a novice here, if you run at 100% does it reduce the life-expentage of the machine or the lenses (where they might need to replaced sooner if driven under max power)?

On an Epilog? No.

That's part of where the extra zero on the price tag came from.

[Scott Memmer]

On an Epilog? No.

That's part of where the extra zero on the price tag came from.

Lee, thanks. Agreed. Wonderful machine.

As a younger man I worked for twenty-five years in the home and professional audio industry, first in retail, then for many years as a field rep. I was an extremely lucky to be an Alpine Car Audio, Nakamichi, and other high-end brands in the hey-day of car audio in the eighties and made a boatload of money In that world it was well-known that the most reputable and high-quality lines always underrated their RMS power output by sometimes as much as 50%.

When I was in retail, we used to get these cheap home stereos for $100 where the box would say "100 watts of power." Total bunk, right. The true rating is continuous RMS (root mean square) power output. They were rating peak power that would last for, like, a nano-second. We used to call those power ratings the "ILS" rating -- "If Lightning Strikes."

sm

[Bert Kemp]

Just remember that the 30000 $ machine is not going to cut any faster the the 10000$ machine of the same wattage. If you want to know the true wattage of a CO2 laser check then tube length and dia. Length: 1225mm Diameter: 80mm Expected Life: 10,000 hours Laser Tube, 80 Watt RECI ..Some companies won't even tell you the tube lenght in their machine. you can bet its not the wattage they say it is.

[Lee DeRaud]

Just remember that the 30000 $ machine is not going to cut any faster the the 10000$ machine of the same wattage. If you want to know the true wattage of a CO2 laser check then tube length and dia. Length: 1225mm Diameter: 80mm Expected Life: 10,000 hours Laser Tube, 80 Watt RECI ..Some companies won't even tell you the tube lenght in their machine. you can bet its not the wattage they say it is.

This would probably be a great time for a comprehensive discussion of the differences between "glass tube" lasers (Rabbit et al) and RF lasers (Epilog/ULS/Trotec etc).

That's kind of above my pay grade ...if it's been done already, I'd love someone to post up a link.

[Scott Memmer]

Just remember that the 30000 $ machine is not going to cut any faster the the 10000$ machine of the same wattage. If you want to know the true wattage of a CO2 laser check then tube length and dia. Length: 1225mm Diameter: 80mm Expected Life: 10,000 hours Laser Tube, 80 Watt RECI ..Some companies won't even tell you the tube lenght in their machine. you can bet its not the wattage they say it is.

Bert, interesting stuff. In a machine like and Epilog, can one get access to the tube to measure it, or is it buried in the bowels of the machine?

Another question, if I may: Since it appears Epilog (and probably Trotec and other American-made laser cutters) are pretty beefy and overbuilt, is it possible to add a larger tube or other components to goose more wattage out of the machine? My best cutting depths I can get from my unit on the materials I use in my business is about 1/4" max. However, I have sheets at least twice as thick as that.

I don't yet have a benchtop CNC machine, athough we're budgeting out for that to happen by this time next year.

Appreciate your knowledge and insights,

sm

[Scott Memmer]

This would probably be a great time for a comprehensive discussion of the differences between "glass tube" lasers (Rabbit et al) and RF lasers (Epilog/ULS/Trotec etc).

That's kind of above my pay grade ...if it's been done already, I'd love someone to post up a link.

Well, I am behind your pay grade, Lee, so I'm not sure where that leaves me.

Sally forth....

sm

[Bert Kemp]

I think trotec mostly use RF tubes if you want to call it a tube. Im sure the glass tubes can be measured. I wouldn't think you have to worry about Trotec or epi claiming more power from a shorter tube if anything they understate their machines. Its the ebay , glowforge and FSL you have to look out for.

Bert, interesting stuff. In a machine like and Epilog, can one get access to the tube to measure it, or is it buried in the bowels of the machine?

Another question, if I may: Since it appears Epilog (and probably Trotec and other American-made laser cutters) are pretty beefy and overbuilt, is it possible to add a larger tube or other components to goose more wattage out of the machine? My best cutting depths I can get from my unit on the materials I use in my business is about 1/4" max. However, I have sheets at least twice as thick as that.

I don't yet have a benchtop CNC machine, athough we're budgeting out for that to happen by this time next year.

Appreciate your knowledge and insights,

sm

[Kev Williams]

The reason I asked about the 100% power thing is because I suspect some folks feel it'll shorten the life span of the tube.
Since 2001 I've owned 5 C02 lasers, still have them all except for my first, a 25w Universal (rebranded New Hermes Optima), which my BIL has been using every day since I sold it to him (at full power ) 4-1/2 years ago.
I put a rebuilt tube in the Optima about 2006, it's still going strong. The tube it replaced was fine, but 9 years old at the time and the new tube was a bargain so I just went for it.
My LS900 40w I bought new in 2004, that tube finally died last June at 16-1/2 years old.
My Triumph 1390 'dumpster' (the crate was exactly 4 cubic yards ) is exactly 7 years-6 weeks old, the 80w RECI shows no signs of stopping. It DOES have a meter, and I've never run it past 27mA.
My 30w GCC Explorer I bought used about 5 years ago, it's a 2005 model, original tube, still going strong. About 3 months ago I had to replace the red LED, and doing so forced me to re-align the FOUR mirrors. I now have more power than before
and my LS100 I got about 3 years ago as a factory refurb, it's about 8 years old I think- they recharged the original Coherent 35w tube, it's now testing at 47 watts. Still

Bert makes a good point about not running a glass laser at 100% power, because, I know many, like my Triumph, have their controller set for TESTING output of 30+mA. My Triumph hits 27mA at 72% power, so 72% is my Triumph's 100%. And, the lower the tube's rating, the lower the safe mA maximum (although I'm not sure of those numbers)...

So I at least, have gotten very good service out of ALL my lasers, including my fibers.
--knock on my head--

[Rich Harman]

100% power can mean many different things.

Most glass tubes have a max rated power, a max recommended power, and a max recommended power for long life.

The controller also has a 100% setting (some only go to 99%), which only means that it is sending a signal of 100% to the laser power supply. The laser power supply must also then be tuned properly to drive the tube at the desired output power.

The only way to really know what power the tube is operating at is to use an ammeter, then you can tune the power supply so that 100% on the controller is equal to 100% of your max desired output power - which should be less than the tube is capable of in order to allow the tube to last a while.

It seems that a popular shortcut is to just tell people to run at 80%, but without an ammeter you have no way of knowing what that really is.