What laser for etching steel?

I'm investigating the prospect of laser etching my knives, most of which I make out of 1075, 5160 high carbon steel, W1 and W2 tool steel and very occasionally 12c27 and 14C Stainless steel.

I'd like to etch artwork on the blades from time to time, as well as my makers mark.

There are bloody millions of the things online, just to make the choice easy.... not.

I realise like everything, you get what you pay for, but I need a machine to etch these metals, and being blades, they are thin, no more than 50mm wide and up to 400mm long.

I don't want to pay too much for too many bells and whistles I don't need.

Any help please?

Baz.

P.S. My current makers mark is electro etched.

 

Can't offer much advice for laser types etc but I'd be thinking more in terms of the etch/engraving area than overall size, the blade CNA overhang the table as long as the laser can get to the bit you want to engrave. I bought a 3018 (300 by 180mm work area) router a while ago and the next size up was much more expensive. It came with a 2.5 watt laser but I haven't used it yet.

 

The two things you need to think about with a laser are the wavelength of light it produces and the amount of optical power it puts out. Generally, what you can etch/cut with a laser is set by the wavelength, and the speed you can do it is set by the optical power. This is a massive generalisation (you can cut metal with a CO2 laser, you just need a lot of power), but it's useful to keep in mind.

The best option for metal marking is a fibre laser (operates in near infrared, at a wavelength around 1000 nm). A 20 W laser would likely be enough power to mark steel, but you're looking in the $4000 plus tax range even importing from China.

CO2 lasers (10000 nm wavelength) generally can't directly mark metals unless you've got a tube that can output more than 150 - 200 W. That said, you can use a spray called Cermark which when hit with the laser makes a permanent black mark. It's expensive, but you can get comparable results with Dry Moly spray lubricant. We've done this quite a few times now and had great results.

Some diode lasers (usually blue, ~ 400 nm) claim to be able to directly mark steel, but I've not tested this. Most people I've seen using diode lasers to mark metal use the Dry Moly trick as above

Please consider your safety if you're looking to get a laser - they're commonly sold without shielding, and even diffuse reflections can be dangerous.

 

Thanks guys. Much appreciated.

Baz.

 

I think the glow forge can etch steel if you use a paste on it first.

Might be worth looking into that

 

as mentioned by zak,

you can get sprays that are burned by the lazer and create fairly decent marks. I haven't used it but darkly labs (aus made emblazer creators, diode lazer) recommend a product call spectrumark,
https://pulselasersystems.com.au/product/black-spray-can/

though it doesn't mention carbon steel but i would think if it can do stainless it should be ok. not cheap at $110 a can, but the pastes are cheaper.

the emblazer laser is pretty decent, though no where near as powerful as the co2, but it does pretty much come plug and play out of the box with out the worry of slapping together a chinesium brand thing together. being aus owned their support is dam good as well.
https://darklylabs.com/emblaser2/

 

I've got one of the original Emblazer units, 3W blue diode laser, and have tried the Dry Moly option - lets just say you need much more power than 3W. it'll mark it as expected, but it is easy to remove.

 

I'm in Canberra and have a emblazer2 Im happy to sell if you wanted.

 

I've marked knives with a Neje A40640 15W dual UV laser module. The spot is tiny though so scans might take a while. Upside is you can get great resolution if your mechanical and control setup is good. I don't know what their xy system is like but would probably do the job

 

I'm not sure it's up to the task of etching hardened steel?

 

Does it have to be laser etched?

 

The electro etching in that video is what I currently do for my makers mark.

 

Pretty much what _ZAK said. You need fibre to etch steel and you’re looking around $6500 for a local unit (less from China but with more hassle and import fees and no support. But still multiple thousands).

Or can use a marking medium like cermark and a CO2 or diode laser to “set it”. While most people use the spray, you can actually get it in multiple formats. For logos on knives, the tape would be most easy to apply, remove and reduce waste. Cermark contains molybdenum which is why people have used moly spray to similar effect. But cermark also has glasses/ceramics that fuse so I would expect it to be more durable than a plain moly spray even if it looks as good off the laser.

Theres also people on FB who make hardened steel stamps suitable for marking blades (either hot, or even cold depending on the temper at the logo location). Dar Lu seems to be the most popular for these.

 

Sorry, I didn't see that PS comment at the end of your first post

 

Dar is a personal friend of mine. I have a couple of his stamps that I use to stamp my heavy tooling I make.

I'm more interested in the laser for etching artwork on the blade. Artwork changes for every knife, so it's not even close to practical to create a stamp for that.

Thanks for all the schooling on lasers folks. It's big money, so hiring laser services might be a better option to buying one, until such point that I am doing artwork on all knives and there is a market for it.

Cheers,

Baz.

 

send me a test knife that i can ship back to you and money for a 6 pack and i'll get a can of that etching spray and i can try it out on my emablazer 2 if you want? can see how well it lasts?

 

Can't fault this logic. There's a lot to learn (as with everything), and while it might be cheaper cost-wise to purchase a laser, you could probably do far more productive things in the time spent learning, not to mention the cost of mistakes!

 

We use Cermark with an 80W at work for stainless labels. Eventually the marked writing wears away in service, industrial use with oils and solvents. I much prefer engraved labels for longevity.

At least I can guarantee your knives won't be seeing the same levels of abuse, so might be ok.