Signing my bowl using a laser

[ChrisA Edwards]

This is the first bowl I used my Ortur LM2-20W ($300) laser to sign.

[John Keeton]

Impressive!!

[Ted Calver]

Very nice. It seems to work great...and you get a consistent signature.

[ChrisA Edwards]

Yes, as stated on another forum, I've bought three different branding irons, one electric and two that you heat with propane, but unless the wood is completely flat, I haven't managed to get a really nice consistent brand, especially if the brand spans different species of wood. I've tried using a laser thermometer to be as accurate with the heat, but haven't found that to be consistent.

So I figured I'd buy this cheap laser ($300) and give it a try. I could have bought an even cheaper one, but settled on this one.

So far I've done this bowl and seven cutting boards and all have been good.

[Brian Tymchak]

Chris, where did you get your Ortur?

[ChrisA Edwards]

I ordered it from Gearbest.com (China). Took about 3 weeks to arrive.

I also see Amazon has them listed today. I checked when I bought mine and they did not. Although they are bit more expensive through Amazon.

https://www.amazon.com/ORTUR-Laser-M...xpY2s9dHJ1ZQ==

I bought the 20W model, but after being on the Ortur Facebook group for a couple of weeks, the general consensus is that the 15W is a better unit for engraving, it has a tighter laser focus.

[Dueane Hicks]

very nice; I wonder how far below the laser itself that it will work? For large or deep bowls.

[ChrisA Edwards]

The floor or bed, of my laser cabinet, sits on a Lab Jack (minute 3:30 in the video). This gives me about 10" of Z adjustment.

My homemade cabinet has a lower shelf, which I could remove and, in theory, set at a lower height.

For my laser, the setup distance to the top surface of the workpiece is 35mm from the base of the heatsink on the laser head.

[Mick Fagan]

Quite an impressive build sequence there. I noted what looked like a Laguna Revo 2436 in the background, with a steady hanging on the end.

Not trying to teach you to suck eggs, but is there a fine focus adjustment system you have worked out?

I ran 50W to 60W Lasers for around 16 years in my last business and working out the exact focus point of the beam is relatively easy, one then just adjusts the focus adjustment to that height and you are laughing.

I would suggest you may wish to think about adding air assist, whereby compressed air is travelling with the Laser head and blowing a very fine amount of air around the cutting point. Air being 80% nitrogen is certainly a cheaper way than using bottled Nitrogen, which is what we used.

Adding air assist may work quite well, or it may not, but adding it shouldn't be too hard for your workshop I would surmise.

Keep the focusing optics clean as anything, they get a build up and the crud hardens on the face of the optic, eventually cracking the glass, or plastic. The build up is on the inside and outside. Once there is a build up the beam gets fatter as it is spread by the crud, if you used a Laser day in day out you get a feeling for things like that. Cleaning, cleaning and more cleaning, is the name of the game.

Mick.

[ChrisA Edwards]

Quite an impressive build sequence there. I noted what looked like a Laguna Revo 2436 in the background, with a steady hanging on the end.

Not trying to teach you to suck eggs, but is there a fine focus adjustment system you have worked out?

....

Mick.

Yes, that is a Laguna 24-36 in the background, had it close to a year now, but it sat idle quite a lot while I finished up a big house, workworking related, project that consumed most of the space in my shop.

The Ortur laser has a lens that sits in a screw in adapter, which gives a few mm's of adjustment for find focusing. There is no Z height adjustment on the laser module, as delivered, where it mounts on the X axis gantry. Many folk offer a 3D printed adaptor that gives a couple of inches of Z adjustment. This allows people with a fixed flat surface to adjust for different thickness materials.

Ortur, the manufacturer, currently sells the same basic unit with three different laser heads, 7W, 15W and 20W. They have suggested focal length settings for each laser module.

I plan on adding a home made air assist at some point. Again, there are many home brew methods out there, simple and cheap. I appreciate your advice on keeping the optics clean, but the lens assembly, for this unit, costs about $20, so it's not that much of a major concern.

I don't plan on doing any major cutting with this unit, it doesn't have the power of the CO2 units, so what it can cut is pretty limited, plus with saws and routers, etc., at the moment I don't have a need.

[Alex Zeller]

What would be really cool is if you could mount the bowl to your lathe and have it rotate to work with the laser so you could do the engraving around the outside edge of a bowl.

[Wes Mitchell]

Your enclosure looks good, but I'd make sure that it will stop the 445 wavelength beam from your laser. I started on SMC by following the laser forums, and Dave Sheldrake frequently warned people every time they mentioned these diode lasers. The wavelength will go right through glass, and apparently if it touches your eye it can burn it out without much feeling, so you don't even know it happened. If it came with glasses I'd make sure to wear them every time.

[ChrisA Edwards]

Thanks for your concern. The Orange Plexiglass is OD3 rated, but already suffering some issues with my eyes, I always wear my OD+6 safety glasses as well and for the most part, I lay a large 55G black lawn and leaf bag on top of the cabinet.

[Brian Tymchak]

Chris, would you happen to know or tried to cut wood with your Ortur? I've had a project in mind for years that requires cutting 1/8" stock, but prices of lasers have kept me from moving forward. Not sure if 20w is enough to cut 1/8".

Thanks!

[ChrisA Edwards]

For what I've read, on the Ortur facebook group, 1/8"/3mm is about the limit for the 20W unit and it may take two or three passes.

The other issue is that to cut nicely, you need an air assist to blow the debris out of the cut line.

This is a mod that I will add to mine at some point, cheap air pump and some means of directing the jet of air to the cut area of the laser beam. People are printing 3D versions and there are a couple of after market add on's.

Found this example