Desktop CNC engravers- mystery machines from china

[auntiebling]

i'm slowly reading through all of this, several times. i'd like to get a used machine, there are a few around locally

re: aluminum. i know it'll be slow going and small parts. feeds/speeds etc i'm not trying to carve out big parts. i see it being pretty handy at making templates that need to last a little longer than an MDF/wood product version would and those can be pretty thin.

there is someone selling a couple machines on facebook

https://www.facebook.com/marketplace/item/4443468072348438/
https://www.facebook.com/marketplace/item/420622035618731/

both use a buildbotics controller setup which seems to take care of some of the integration of rPi and such i'm not really comfy with and don't want to sink time into just yet. that first one has a 1.5 watt spindle, i bet i can really destroy some cutters with that!

anyway, anyone looked into the buildboticscontroller? the integrated computer that can be controlled wirelessly i thought was a little gimmicky but reading further explanation could be very convenient. it's also something i could use if i ever get to adapting my benchtop manual mill to cnc

 

[cheez]

Unfortunately there's an enormous price rift in lasers. There's the lowly K40 which can be had for $400, but you'll end up dropping another $2-300 before it's actually useful. But then there's not much of anything until you are ready to drop $2500 on the laser Mike Warren reccomended.

The only one I know of in the middle is the Beamo, which came out of a kickstarter project for a little over a grand. I've heard good things but I don't know much about it.

I still just have a K40. Its great, but it also sucks.

Have you ever tried to cut a license plate on it?

 

[TylerW]

I haven't ever used a machine using the buildbotics controller, but it seems like a good resource to know about - when I get a bit of free time I'd like to build a camera motion control system and I'm debating if I want it to just eat GCode for programming it instead of building a custom interface, which might be more limiting further down the road.

the arrangement of the USB ports and Ethernet jack tells me that the buildbotics controller is still running on a raspberry pi -no issue with that, and I'm sure their software hides all those guts from the end user. It just amuses me.

For anyone curious, this is an aluminum part I cut recently on my home machine. Just a few simple operations, two pockets that were cut to a 1mm depth and the long slot in the center that was cut to the full .125" depth, and the four screw holes. All told, I'm really happy with the surface finish on the walls of the cut. And this is with a cheap wobbly X-Carve, a dewalt palm router for a spindle and cheap bits made of pure chineseum.

 

[TylerW]

Have you ever tried to cut a license plate on it?

Welp, I've got a laser and a license plate. I'd be happy to chuck it on there and film the results.

What are license plates made from? 18ga aluminum?

 

[auntiebling]

Buildbotics is upfront about using the raspberry pi, its sort of a selling point. They aren't doing anything new, just letting people skip the rpi/controller/driver assemblage/integration step. I think

 

[byke]

Why Glowforge? Are you looking for the ease of use? The size? Glowforge offers a simple, slick interface for shooting lasers at stuff, but its also relatively underpowered, and very expensive.

Mike Warren from Instructables just did a video for Cool Tools talking about the laser he just bought. It's 80w, much bigger, and cheaper than the glowforge. You do need a decent amount of shop space to dedicate to it, and while Glowforge is great for showing videos of people using it in the living room, you really shouldn't - lasercutters are boxes of deadly fumes that need good ventilation and exhaust so you don't kill yourself or others.


youtu.be/7P661CYrgh4

I'm guessing he didn't look at the reviews for toolots. :laughing

 

[TylerW]

As promised, I tried, and I failed. A 40w laser tube, full power at 5mm/sec did not make even a mark on a CA license plate.


youtu.be/NZrn3so79b8

 

[cheez]

Well damn. Thanks for trying, at least!

 

[TylerW]

TBH I knew it wasn't gonna work. But you're a good duder and I didn't mind taking the time - especially since I wasn't sure what the outcome would be, if anything.

Those state outlines you're doing are cool, but I don't know that a scroll saw isn't the best way you could be doing it. Then again, I don't know how much time it takes you. I reckon a big CNC router could work for you, maybe also a CNC plasma cutter.

There's also a few home waterjets you can use, but you're gonna be limited in cutting area and waste management can be a pain - they don't use as much water pressure as commercial machines, so they use a ton more media in the process.

That said, I'm not gonna knock owning a laser either. Mine has already paid for itself 4-5x over in just this year alone. My entire etsy shop is full of products that were made on my laser.

 

[cheez]

TBH I knew it wasn't gonna work. But you're a good duder and I didn't mind taking the time - especially since I wasn't sure what the outcome would be, if anything.

Those state outlines you're doing are cool, but I don't know that a scroll saw isn't the best way you could be doing it. Then again, I don't know how much time it takes you. I reckon a big CNC router could work for you, maybe also a CNC plasma cutter.

There's also a few home waterjets you can use, but you're gonna be limited in cutting area and waste management can be a pain - they don't use as much water pressure as commercial machines, so they use a ton more media in the process.

That said, I'm not gonna knock owning a laser either. Mine has already paid for itself 4-5x over in just this year alone. My entire etsy shop is full of products that were made on my laser.

It's just tedious, it's not "hard" if that makes any sense. I just have this optimal solution in my head where I'm feeding whole plates into a laser cutter, it's producing the component shapes with the rivet holes pre-cut, and I can spend my effort on assembly. I didn't figure it was such a tough medium. Meh.

 

[Sharxfan]

I started reading this and was waiting for TylerW to chime in he does some cool things.

I have seen where people have converted cheap 3D printers to laser cutters by removing the print head and swapping in a laser. I haven't really looked into it but it maybe something to look into as you get all the parts for cheap and just need the laser and some plumbing. I may have seen it on Hackaday or somewhere similar.

 

[TylerW]

I started reading this and was waiting for TylerW to chime in he does some cool things.

I have seen where people have converted cheap 3D printers to laser cutters by removing the print head and swapping in a laser. I haven't really looked into it but it maybe something to look into as you get all the parts for cheap and just need the laser and some plumbing. I may have seen it on Hackaday or somewhere similar.

I'm pretty deeply inculcated in the hobbyist and semi-pro machines. There's some other folks on here who are deep in the pro end who are laughing about everything I post, because I don't know shit on their end, and they're right.

Anyhow, I'm not a big fan of multifunction machines, because each function affords significant compromises against the other. Adding a laser to a 3d printer is probably the least compromised, but any laser you can add to a printer will likely just be a low-watt diode laser. While you'll be able to engrave wood, acrylic and other soft materials, you won't be able to cut through anything other than thick cardstock.

 

[brichter]

This is what I love about Amazon:

Exquisite 3040 is a miniature version of mobile longmen structure of carving machine,put on you computer is like putting a printer or scanner that coordination,and can completely as a compute peripherals tools, anywhere, anytime, help you to design intent fast real appear.

:laughing:laughing:laughingarty

 

[wilit]

Hey, that's my video! Like, that's literally me in the video and my old garage shop in SF! :laughing

Okay, so a bit of my knowledge dump on what I've learned about CNC in the past few years. There's a ton of different ways to generate your CAM and GCode. Easel is one of them, it's the most user friendly, but its also the most limited. Pretty much the only thing I use it for is V-Carving, which means that you're using a bit that's tapered so you can generate designs with tight corners.

Another option for CAM is Carbide Create. You don't need to run it through a web interface, it can also generate V-carving toolpaths, and in general it's a little more powerful and versatile.

Most of the time I'm generating GCode in Fusion 360. They recently reshuffled the hobbyist licensing in Fusion and hobbled the CAM portion of it. The worst part about the new licensing is that you can still generate toolpaths, but it will no longer generate rapid movements - which means that when your bit is traveling above your material from one operation to another, it will be moving at your cutting feetrate - which means that your overall machining time per part will be considerably higher.

I'm still sending my GCode through UGS on a a rasPi - it's still a system that works for me. I'm considering moving it over to a cheap fanless PC so that I can run my laser from the same computer - more on that later.

As for materials, you *CAN* machine aluminum on cheap machines, it's really a question of how patient you're willing to be. There's a ton of deflection in these cheaper machines which means that you need to make shallower cuts and lower feed rates. The lower feed rates means that you're putting more heat on your tool and shortening your tool life. But if you want to make a few one-off parts out of .125" or even .25", it is possible. You need direct air to clear the chips and some lube definitely helps. You're not going to be making a top triple anytime soon, but custom mounting plates? Heck yeah!

But in general, you're better off with wood, carbon fiber, G10, acrylic, or HDPE. MDF machines really beautifully and I just made some parts out of HDPE last week.

For deep diving on machining on hobbyist machines, Check out Winston Makes. - he works for Carbide (who makes the Shapeoko machines) but he's got a ridiculous amount of knowledge about toolpaths, machining strategy, feeds & speeds, plenty more.

I'll have more to say about laser cutters in another post.

Dude, thanks so much for that vid. It was very helpful since my Linux/Raspbian is a bit rusty. Couple of follow up questions.

UGS on the Pi. The visualizer isn't working. I looked it up and only found a single how-to on getting it working. Is it worth it to jump through the hoops or is there a better G-code sender out there? I'm leaning towards bCNC.

Carbide. I looked it up and it looks more like what I'm into... Free. But looking through the machine setups, it looks like they only have Shapeoko machines. Is that critical to having the 3018 profile in there to generate good G-code? I'm pretty proficient in Fusion, but for the simple engraving projects I'm using the 3018 for, it's way overkill. And yes, I agree with you on the licensing. But it's a brilliant monetizing model. Get users hooked, then start charging. I also use Sketchup and Fusion is lightyears better.

 

[wilit]

i'm slowly reading through all of this, several times. i'd like to get a used machine, there are a few around locally

re: aluminum. i know it'll be slow going and small parts. feeds/speeds etc i'm not trying to carve out big parts. i see it being pretty handy at making templates that need to last a little longer than an MDF/wood product version would and those can be pretty thin.

there is someone selling a couple machines on facebook

https://www.facebook.com/marketplace/item/4443468072348438/
https://www.facebook.com/marketplace/item/420622035618731/

both use a buildbotics controller setup which seems to take care of some of the integration of rPi and such i'm not really comfy with and don't want to sink time into just yet. that first one has a 1.5 watt spindle, i bet i can really destroy some cutters with that!

anyway, anyone looked into the buildboticscontroller? the integrated computer that can be controlled wirelessly i thought was a little gimmicky but reading further explanation could be very convenient. it's also something i could use if i ever get to adapting my benchtop manual mill to cnc

What are you trying to use the CNC for? The problem with both of those and most of the other machines we've mentioned is they're not real mills, they're really CNC routers. The Z axis travel on most routers is really limited, so you can't really cut stock much more than an inch or two high. Also, like TylerW mentioned in another post, the deflection on the Z axis is bad. I was cutting MDF on my 3018 at too high a feed rate and it was deflecting a good 1/8".

 

[wilit]

It's just tedious, it's not "hard" if that makes any sense. I just have this optimal solution in my head where I'm feeding whole plates into a laser cutter, it's producing the component shapes with the rivet holes pre-cut, and I can spend my effort on assembly. I didn't figure it was such a tough medium. Meh.

You probably want a CNC Plasma. Langmuir Systems has a pretty affordable table ($1500). Then add a chinese pilot arc plasma for $400 and you're cutting metal.

https://store.langmuirsystems.com/products/crossfire-cnc

 

[TylerW]

Dude, thanks so much for that vid. It was very helpful since my Linux/Raspbian is a bit rusty. Couple of follow up questions.

UGS on the Pi. The visualizer isn't working. I looked it up and only found a single how-to on getting it working. Is it worth it to jump through the hoops or is there a better G-code sender out there? I'm leaning towards bCNC.

Carbide. I looked it up and it looks more like what I'm into... Free. But looking through the machine setups, it looks like they only have Shapeoko machines. Is that critical to having the 3018 profile in there to generate good G-code? I'm pretty proficient in Fusion, but for the simple engraving projects I'm using the 3018 for, it's way overkill. And yes, I agree with you on the licensing. But it's a brilliant monetizing model. Get users hooked, then start charging. I also use Sketchup and Fusion is lightyears better.

Thank you! I'm so glad that it's helped you!

I've never gotten the visualizer to work, and as such, I've just kinda lived without it. I just use the timer, and my simulations in Fusion CAM to get a sense of where I am in the overall timescale of the operation. I think it's just a limitation of the graphics capabilities of the Pi. It might be better with the Pi 4, I'm not sure.

I've been running larger jobs recently on the 4x4 cnc at my makerspace, and that machine runs Mach4. The visualizer is certainly helpful, even if it's just 2D. But seeing where the bit is, and its current depth on the DRO is raelly nice. I know the visualizer works on other hardware like Windows, so that's another point in favor of moving up to a fanless PC.

Where are you getting hung up on machine setup in Carbide Create? I'll admit it's been a minute since I've used it, but I just downloaded and poked around a bit. I have no idea what flavor of GCode your machine accepts, but I'd be surprised if it didn't use GRBL.

Like you, Fusion CAM is definitely overkill for most of what I do. I still enjoy it because I've come to enjoy the level of control it gives me over the process, and I feel like I learn something new every time I generate a new toolpath. That's important to me.

I still love that we have access to these tools. I first learned CAD back in high school in the early 90's, and I knew then that my designs could be used to create actual, physical parts. We had a desktop Roland mill in the classroom, but no one knew how to use it, including the teacher. It had no documentation, and no tooling. A lot of this is some pure, teenage wish fulfillment for me.

 

[TylerW]

What are you trying to use the CNC for? The problem with both of those and most of the other machines we've mentioned is they're not real mills, they're really CNC routers. The Z axis travel on most routers is really limited, so you can't really cut stock much more than an inch or two high. Also, like TylerW mentioned in another post, the deflection on the Z axis is bad. I was cutting MDF on my 3018 at too high a feed rate and it was deflecting a good 1/8".

That's some INSANE deflection!

I was recently doing some test cuts in HDPE since I hadn't worked with it for a while. I was using a .125" 2-flute upcut bit. My recipe (outer contour cut) was .025" depth of cut and a feedrate of 100" per second. The speeds felt insane, but the cuts came out perfect. I made a video of it here: https://www.instagram.com/p/CIJt-MwhZJX/?utm_source=ig_web_copy_link

 

[Dubbington]

Been looking into these to do custom engraving in cutting boards and other wood items. Don't really have the space for one currently BUT still intrigued.

The high watt lasers require a co2 supply right? Also I've noticed many of the cheaper ones have a small table. I make boards sometimes 15x22 and the laser would be to straddle the board in order to engrave correctly.

 

[TylerW]

The high watt lasers require a co2 supply right? Also I've noticed many of the cheaper ones have a small table. I make boards sometimes 15x22 and the laser would be to straddle the board in order to engrave correctly.

Not exactly sure what you mean, so I'll overexplain what I know. Most hobbyist/prosumer lasers are CO2 lasers, but the carbon dioxide in this case is the gas within the tube that the laser beam is generated in. It determines the wavelength and properties of the laser, but that's it. The gas is sealed within the tube and does not need replacing. The laser tube has a service life and will eventually need replacing. They generally have an expected service life measured in hours - generally 1000-2000 hours depending on how its used.

The tube does need active water cooling. My setup is fairly ghetto - 4 gallons of distilled water in a sealed Lowe's bucket fed through an aquarium pump. It works.

For most cutting operations, lasers perform best with what's called "Air Assist". This is a stream of air that blows, ideally, coaxial to the laser beam. This stream of air blows any smoke or other debris from the cutting operation clear of the laser beam so it can continue its work unobstructed. You can run your air assist from an air compressor, which I'm assuming you have. I run mine from a small air pump - I would like to upgrade it soon.

Anyhow, the air assist is just normal-ass atmospheric air. nothing fancy.