[coder543]

Yeah, my larger point is that there are already plenty of ways to cut metal in a home workshop.

I don't see how a laser would be an improvement on any of those, unless the goal is to CNC with extremely tight tolerances, but even then... it seems unlikely that you'll be CNCing blocks of metal, more likely just 2D cuts from sheets of metal, which is pretty limiting.

It would certainly be fun for some stuff, but I think the danger level of a super high power laser detracts from the fun.

More powerful cutting lasers would definitely be great for industrial use cases.

[alanbernstein]

I use a 120W laser cutter for practical, precise, CNC projects all the time. I use a lot of 1/4" acrylic because it's a good material for this class of machine, but it's not the best option, structurally. If I could do the same with 1/8" or 1/16" steel, I would likely switch to that for almost every project.

I love the idea of using a mill/router instead, but IMO the more complicated process is fundamentally more dangerous. If a reflected beam can conceivably pierce the enclosure though, hmmm...

[83]

The precision of a laser cutter would open up a lot of possibilities. Particularly making things that slot together with tabs - like fabbing my own welding squares and fixtures where a cnc plasma cutter would leave too rough an edge to have them slot together accurately.

[coder543]

Can't you buy a CNC mill/router that can cut metal more precisely than a CNC plasma cutter?

[83]

You can't cut sharp inside corners using a cnc mill (round bits), as one would want for tabbed fixtures.

Most sheet good are too large to be placed on or moved around by a cnc mill table.

CNC milling is a slow process (unless you can drop six figures on one).

CNC mills take a lot longer to setup and program, and also require more skill to have a successful result (no chatter, not breaking bits, ramping into the cut on interior features).

Good CNC mills that can handle steel are massively heavy and large machines which makes transport and setup difficult for the home machinist.

[mrWiz]

Not cheaply, which was part of the OP's post.

[coder543]

Yes, for relatively cheaply. I’m not talking about a 5-axis CNC mill, and I’m not saying it’ll be fast. But a laser cutter is not fast either, and even if lasers get more powerful… a really powerful one is unlikely to be “cheap”.

[alanbernstein]

Of course it depends on what you're doing, and what you're comparing to, but in my experience, laser cutting is the fastest option for hobby-level fabrication.

[bsder]

Tormach metal CNCs are $10K+ and take up a lot of floorspace.

A lot of people also cut sheet metal which a CNC tends to be terrible at.

[coder543]

We're talking hobbyist grade stuff here. People mount router bits on $400 CNCs and cut metal all the time.

Not $10k: https://youtu.be/w26DHMccicE?t=637

Even though it's cheap, the cuts still look pretty smooth and precise. I can't speak to the safety, as I would hope a $10k CNC would have more safety features.

[bsder]

They cut aluminum. Generally not well.

This part is actually a typical good result in spite of how bad it is: https://youtu.be/w26DHMccicE?t=731

Deflection is bad. Repeatability is poor. etc.

If you put even mild steel on that, that machine will have no hope.

[coder543]

Okay, but if you’re expecting a magical new diode laser to cut steel any time soon… good luck. That’s what most of this discussion is about. I think starting with a cheap CNC is more likely to work out.

[91bananas]

Completely different processes for completely different things.

[coder543]

Yes, and a laser cutter is also a completely different process for completely different things... yet you can still do some of the same things, and a CNC mill would be more appropriate for smooth cuts than a CNC plasma cutter.

[mft_]

You're right that such things already exist; I think it would offer two incremental improvements:

* for wood, faster and/or thicker cutting, vs. existing CNC laser cutters

* for sheet metal, neater/cleaner cutting (i.e. cleaner cuts, higher tolerances, less subsequent prep-work needed) perhaps in a smaller neater machine, vs. existing CNC plasma cutters.

Especially within the context of a CNC machine, I wouldn't be overly concerned about safety - all of the more powerful CNC laser cutters I'm aware of already come with an exclosure - both for laser safety, and to constrain smoke (before it's vented safely).