New to Laser Cutting and Looking for Some Advice

(Eirik H) #1

I’m brand new to laser cutting (bought a 100w red chinese laser from ebay) and lightburn as well. I have gone through all the lightburn video tutorials which have helped me greatly getting me into the process but I have a few questions.

To start, I am getting into laser cutting specifically to augment my other manufacturing pipelines for product prototyping. I am experienced with CNC’s, traditional milling and 3D printing so please if I am using the incorrect term for laser cutting let me know.

  1. Are there any good rules of thumb for beginning speeds and power settings? Are there any resources that offer starting points for materials based off the laser wattage etc?

  2. Are there any materials I should absolutely avoid and is there any online lists of these materials? I read that neoprene releases chlorine gas when cut etc and don’t want to inadvertently endanger myself or others.

  3. Does anyone have any recommendations for source/brand of compounds that work well for engraving stainless steel? I’m located in the US midwest if that impacts your recommendation.

Thank you in advance.

(Rick James) #2

I moved this post here as this is more about general laser use and not LightBurn specific.

I find the best approach for choosing a starting point is to use a test file on a sample of the desired substrate and test, test, test, until dialed in. Each laser, tube and hardware setup has slight (and sometimes large) differences that only testing can reveal.

Here is a sample test file that will require adjustment for your setup:

And a discussion about how to use the ‘Power Scale’ feature in LightBurn:

(Eirik H) #3

Thank you Rick I appreciate you taking the time.

(Oz) #4

Boss Laser has a list of starting points for settings on their site, with different values for different wattage machines:

It won’t be perfect, but it should get you going.

For materials, Google is your friend - there are lots of online guides that will tell you what is safe, what is “mostly safe”, which materials don’t work well, and which ones to avoid completely.

In the never list, most prominent are PVC and vinyl, because they contain chloride compounds which turn into toxic and corrosive gas when burned. They’ll corrode the metal parts of your machine, kill you, and it’ll hurt the whole time you’re dying. (some people do cut these things, using very high performance exhaust systems and scrubbers)

Acrylic cuts well and is used often, but the fumes are bad for you, so make sure you’re venting outside.

Natural materials like natural woods, slate, leather, and felt work very well. Be aware that leather and felt smell to high heaven when burned (think burning fingernails and hair respectively), but they aren’t harmful.

HDPE melts and gets all over everything, polycarbonate resists lasing and mostly chars and blackens, and polystyrene has a tendency to melt and catch fire.

For metal marking, Cermark is kind of the industry standard, though it’s pricey. Dry Moly lube works well (though not quite as dark) and is significantly cheaper.

Engraving materials besides wood
(fred ungewitter) #5

For marking at a lower cost, Laser Bond 100 is great stuff. I’ve found the aerosol can permits the most consistent application, although with the right equipment, the liquid product probably does as well.

(Eirik H) #6

@LightBurn thank you for taking the time to respond.
The starting points were exactly what I was looking for and have already saved me time and material waste this morning!

Thanks for the tip on the PVC and vinyl, I’ve added them to my printed list on the front of the machine for a reminder.

I’ve review the cermark, it appears that I can get it in 25g bottles and test and go from there.

Thanks again.

(Eirik H) #7

@fred_dot_u Thanks, I’ll check out the laser bond 100. I appreciate the heads up!

(fred ungewitter) #8

Oh, yeah, I almost forgot one somewhat incredible marking material. Mustard.

Yes, mustard. I tried it on some stainless I had as “scrap” and the Gouldens version didn’t work well, as it’s lumpy and inconsistent. Grey Poupon is much smoother and produced a cleaner marking. It’s not as dark as Laser Bond 100, but it’s a great deal less expensive!

The video is the one that I discovered, and the user has a 4 watt diode laser just like my “toy” that introduced me to this hobby. If he can get this great result on 4 watts, it’s easy to see why it works with ten times as much.

(Rick James) #9

Never personally tried Rust-oleum Textured brown paint, but this post talks about this as an option as well.

(Eirik H) #10

@fred_dot_u thanks, I’ll give it a try!