Laser engraving enclosures with a cheap Chinese machine? Yes!

[culturejam]

One small suggestion: when you align your artwork, align to the center of the enclosure, not to the edge.  I used to align top-left and I was always fighting alignment issues.  I made a small acrylic fixture that holds the enclosure by the screwholes and the artwork is centered on the enclosure.

The boxes aren't exactly precision made, nor is the powder coat, so the outer dimensions can vary a bit.  Center-fixturing helps reduce potential error.

I'll need some of your help getting that sorted out.

This thing does a "trace the frame" movement so you can see the edges of the artwork. I've been using "bottom left" as the homing point since I can visualize that easier than the center. I'm never really sure I'm in the true center, but I know for a fact if I've got the bottom left corner lined up.

But I'm more than willing to learn a new/better way to set this stuff up.

[culturejam]

Alright boys, here's the pudding.

I ran a powdercoated box (from BLMS) late last night. Did two passes at 100% power (full chooch!) at 900mm/min speed. I think this is 95% there.

Switching to imgur for hosting so I can notate things in-line in the post.

Okay, so here's the box right off the laser, no cleanup at all. There is powder ash all over. Stinks like hell, too. Damn this stuff is nasty.




And just below we have after cleaning. For this, I was able to get it looking like this with just 90% isopropyl and a toothbrush. There is still the thinest micro-layer of crust, but it won't come off without scraping. And frankly, I think it looks pretty cool. Sort of gives the metal a "relic" look. But you could, if some motivated, get 'er down the bare metal with a little more elbow grease and a dental pick.

Note: I did not clean the drill art at all, and next design will not have such elaborate markings (takes too damn long to etch and is unnecessary)



The text on "Time 1" really kind of lost resolution, and I think part of this has to do with the slope of the enclosure near the edges. Same thing for the left part of the main circle graphic. Changes in distance from the laser to the cutting surface changes the focus/sharpness of the beam, and that can throw off fine detail. Part of it also probably came from micro-movements in the laser frame over the course of two full passes (I'll get the frame locked down to my bench soon, and this should no longer be an issue).

Also, the drill art circles came out all kinds of not-round. Again, a big part of this is enclosure concavity, and some has to do with frame walk during multiple passes. And still more, sometimes you lose a bit of finish when cleaning, which also make circles look not that great.

Yeah, so it's not perfect by any stretch, but I'm damn well impressed with what a cheap-ass laser can do. With a few more refinements, I think this will be a nice options for finishing on a one-off or short run basis. Need to get some more fixturing improvements (in the works!) and then we'll be in business.

[culturejam]

Forgot to mention: I suspect a third pass might make the final product even closer to metal. But I need to reduce the overall system slop before attempting 3 passes, as there are definitely some issues with precise repeatability of the cutting path from pass to pass. I'm going to adjust some of the firmware parameters to slow down the stepper motor transitions (start > stop and vice versa) and that will help. I'm also going to print some soft feet for the frame using NinjaFlex filament (which will also dampen vibration and reduce frame "walk").

FYI, I'm using a 2.5W diode laser head. I have gotten similar results with a 1.5W laser, but it took 3 passes to do what this one does in 2. Less passes is always better, assuming similar quality.

[EBK]

I'm wondering what a laser etch followed by a rub down with ferric chloride would do.

[m-Kresol]

thanks for your efforts and reports on the progress CJ. I'm still waiting on mine, should be here soon!

I'm wondering what a laser etch followed by a rub down with ferric chloride would do.

the powdercoat is inert against the FeCl3, so you would increase the depth of the etch or stain the metallic parts on short expure times. However, getting the gunk out of the etched parts without ruining the powdercoat and also preserving the powdercoat's colour will be hard.

[storyboardist]

Wow! That looks really good.


...I gotta stop looking at this thread or I'm gonna blow money I don't need to on one of these. lol

[EBK]

...I gotta stop looking at this thread or I'm gonna blow money I don't need to on one of these. lol

So true.  I wasn't going to buy one either.  Now, there is one in the mail almost at my door.   

[jubal81]

Makerspace here has a 12-50 watt Rayjet. Any general tips on power, speed or passes for cutting through powdercoat with it?

[wgc]

Nice! Get a scrap enclosure and then make a file where you can test different settings all in one or two setups. Usually you can assign settings to a color in your file. So mark 1 is blue, and you make the settings for blue 20p,50s, next mark is green, 30p, 50s, etc.

Sometimes makerspaces have a sheet where people can post their settings for different materials. Might save you some time. If they don't have that, it can buy you some cred  to set one up.

Fwiw the laser I used to use was similar specs and pretty much 50-60% speed and 30-40% power was about right in most cases. I generally err on the conservative side and run multiple passes if in doubt.

Definitely try some acrylic etching and cutting.

[pickdropper]

Nice! Get a scrap enclosure and then make a file where you can test different settings all in one or two setups. Usually you can assign settings to a color in your file. So mark 1 is blue, and you make the settings for blue 20p,50s, next mark is green, 30p, 50s, etc.

Sometimes makerspaces have a sheet where people can post their settings for different materials. Might save you some time. If they don't have that, it can buy you some cred  to set one up.

Fwiw the laser I used to use was similar specs and pretty much 50-60% speed and 30-40% power was about right in most cases. I generally err on the conservative side and run multiple passes if in doubt.

Definitely try some acrylic etching and cutting.

So much this.  We got a new 50W Epilog at work and I'm messing with optimal settings and the only difference (other than bed size) is the old machine is 30W and this is 50W.

Also, it matters who does the powder coating.  I goes some cheap Tayda enclosures to experiment on and they etch different than the expensive PPP enclosures.

[culturejam]

Also, it matters who does the powder coating.  I goes some cheap Tayda enclosures to experiment on and they etch different than the expensive PPP enclosures.

Different good? Bad? Just different? 

Asking for a friend. 

[Martan]

Makerspace here has a 12-50 watt Rayjet. Any general tips on power, speed or passes for cutting through powdercoat with it?

Don't know what kind of files your laser cutter will accept, but here's a link to a test file that I think is in .rl format. https://www.bosslaser.com/laser-test-files

There's one for engraving and one for cutting. Works great if you can load it. I always use the bottom plate of the enclosure to test the power, etc. I figure I won't see it much🙂

[pickdropper]

Also, it matters who does the powder coating.  I goes some cheap Tayda enclosures to experiment on and they etch different than the expensive PPP enclosures.

Different good? Bad? Just different? 

Asking for a friend. 

Not as clean as the PPP enclosure for whatever reason.  Definitely serviceable, though. 

What is weird is that the black and white enclosures have all sorts of weird finish problems (uneven, strange shiny spots, etc...) and the other colors have relatively even finishing to them.  They are packaged differently, so I suspect they might get them from different vendors.

[EBK]

My laser engraver arrived today (sort of).  I wasn't home to sign for it, so the post office kept it for now. 

It's 20 days from my order date, by the way.

[m-Kresol]

Got my A3 on Monday. I'm glad I bought the bigger version, it's not that big and I'll be able to engrave other things than pedals too. With Brian's add-on comments to the assembly instruction, it went together rather smooth. had 2 bad threads, but enough spare parts were supplied. A small tipp: put the pins of the Y-axis stepper motors facing down or forwards. I switched those around at least 3 times (including taking apart some assembled bits and pieces)

tried to get it operational on mac yesterday

• the manaSE firmware was a pain in the ass to flash with mac and didn't work after all since I can't use eleksMaker's GUI. Doh!
• Flashing grbl firmware and then using "universal g-code sender" worked well. I can control the stepper motors now
• Still need to find out how to control the laser: which pin the PWM signal is going to and the gcode command, etc.
• during booting the arduino controller will pull every pin high for a bit. thank god I had put an underlay under the engraver or my dining table wood have a nice stain.