Your first laser purchase - what would you have ordered differently?

[Don Corbeil]

Yes, David the capability of a router for deeper relief (and I would assume perceived quality) has had me questioning the practicality of doing that aspect with a laser. For those out there that do a lot of medium/larger piece wood carving, do the lasers leave something to be desired with this type of carving work?

[Mike Lassiter]

Another thing to consider is where you will put the laser. A larger machine means a larger building, especially if you are planning on using pass thru for door and such. I have mine in a 12x32 building and only needed the pass thru on one door to run material in for cutting it. I really need more room around mine but make do.

[Jason Hilton]

I've done both CNC and Laser 3d relief engraving. You get deeper and more efficient relief from a CNC, but it's also messier. It really depends on the type of work you're doing. I prefer using a laser because it's clean and I mostly do small detail work on pieces 2-5 inches across. However it takes a lot trial and error to get the relief you're looking for, because where a CNC controls depth very accurately with a bit, a laser uses a combination of power and speed determined by a grayscale relief image. Differences in the speed and power change the depth and the quality of the finish on the piece. You also have variations between materials, so you have to account for those differences with adjustments to power and speed. If you don't have enough power, you have to do multiple passes, multiple versions of a source image to control depth... There are a lot more variations with a laser, and 3d relief isn't the best use of a laser engraver. You can get amazing results, but it's not as cut and dried as a CNC. I still prefer the laser, but like I said, I do small work with very specific requirements and very little variation. I've also already done all the trial and error. Of course, I'm nearing the purchase of my own laser, so I'm about to do it all again...

[Don Corbeil]

That's informative for me, Jason. I've also heard that to get good quality 3D relief with a laser, it involves pretty intensive work with the image processing software to get those grey areas where you want them for depth control. Perhaps it's the same with setting up a cnc router, but it sounds like it may be trickier with the laser.
However, when you get it right, do you see people being as satisfied with a wood engraving done through a laser, or do they tend to prefer the traditional router product? This is an important element in my decision on how to do larger wood pieces.

[Joe Hillmann]

For what you say you plan to do I question if a laser is the way to go. A lot of what you want to do sounds like larger items than you can fit in a laser.

Take a window for instance. Even if you have front and back passthrough you can't fit the window if it is to wide for the machine, and if the width does fit you may have the problem of lining the part on the x axis if you have to break up the engraving. The same would go for fireplace mantels. You may want to think about sandblasting set up and a plotter for cutting the masking.

Also if you want to do metal engraving with a laser you need to use cirmark to get a mark. I have never used cirmark but there are many threads on the forum asking for help on getting it to work so it seems to be something that takes a lot of trial and error to get it to work. Metal can be masked and sandblasted but the mark doesn't have much contrast.

Wood could also be sandcarved but it takes some skill to get a 3d look to it and even then it will be nowhere near as detailed as CNC.

[Glen Monaghan]

Another issue with engraving relief in wood is the effect of the wood grain. A CNC's results are not (particularly) affected by the wood grain because the bit cuts through harder and softer layers equally. In contrast, a laser's relief results can be significantly compromised by the grain. The laser will ablate the softer wood more than the harder wood so that a wood such as oak will exhibit a sort of rippling effect in engraved areas where the harder parts are left higher than the softer parts. There's basically no reasonable way to correct for this effect with laser engraving.

[Jason Hilton]

Don,

For the products I create, no one viewing the end product can tell the difference. But that's because the 3d engrave is only part of the process, I also do staining, painting, and other finishing work. As Glen mentioned, variations in material will cause irregularities that can't be corrected with a laser process, but that CNC will never encounter. I almost always 3d engrave on softwoods.

In terms of artwork, it really depends on your method of creating it. I use 3d software to create my grayscale images for engraving. If I need to tweak, I tweak at the 3d art level and re-export the grayscale image again. I primarily tweak to control the depth and contour of the engraving, so it's easy and quick to alter 3d geometry. I've gotten pretty good at judging the artwork needs for the machine I'm using. Another consideration: artwork for 3d engraving is a lot less portable, because every machine is different in terms of power, speed, lens, etc., so if you create artwork that you need to do a large laser run with, you can't call up a buddy and just send him a file, you'll have to make adjustments, and matching between machines is a big pain, if you can do it at all. CNC on the other hand can usually accept an actual 3d file with defined depth, meaning as long as you use the same bits, feeds, and speeds (in general) you can get the exact same result on two different CNC machines.

If all you're doing is large relief engraving, I would echo many others in this thread and say that a laser is probably not the tool you want.

[John Bion]

Regarding pass-through capability - I ordered my Chinese Lasers with it, I do not often use the facility, however when I do, I have to match up the the different sections with incredible care or I will err on the X axis or possibly both. The longest piece I handle on the lasers is 6’ (engraved top to bottom). The router is the ideal thing for this, hence my recently purchasing one. The only downside is that you cannot play with settings on a router to achieve darkened/contrast effects as you can on a laser (although depth and line width can be used to some degree on a router - in 2d that is - I have never had the opportunity to try 3d).
Considering the weight of some of the products you are speaking of, this may be an issue for the machine, possibly requiring strain bearing rollers either side to take the weight off of the laser bed. The next problem is the Z travel, a door is not an issue, however a mantel piece could be; not only is sufficient Z from bed to laser head required but also sufficient pass through door depth to where the bed needs to be, most pass through doors are very limited in depth (Z travel).
Doors, window frames etc can of course be engraved on a laser in sections if you are working with the joinery who then complete construction post engraving.

Kind Regards,
John

[Keith Upton]

It sounds like you need a small to med work area on your laser and the balance of the money should be applied to a CNC router. That would ensure that you had the correct tool for the job a hand. You might need to scale back on the options for each to be able to afford both.

Try looking at what you would need laser wise if you already had the CNC router for the large door type projects. Than do the opposite assuming you already own the laser for the smaller stuff.

[David Somers]

Don,

Another thought about using a laser for such a large 3D engraving. Speed? If I remember right, folks discussing 3D work on other threads in the forum have mentioned that 3D engraving is slow as well as highly variable due to differences in wood density across summer and winter growth, etc.

Dave

[Don Corbeil]

It sounds like you need a small to med work area on your laser and the balance of the money should be applied to a CNC router. That would ensure that you had the correct tool for the job a hand. You might need to scale back on the options for each to be able to afford both.

Try looking at what you would need laser wise if you already had the CNC router for the large door type projects. Than do the opposite assuming you already own the laser for the smaller stuff.

With the excellent feedback I'm getting from everyone here, I have to say this is where I seem to be leaning now - starting with a laser system that offers a medium sized work area (possibly with a front door for some oversized flexibility), and with enough power to handle the various materials I would anticipate using. I could do quite a bit with this setup to start with and not break the bank, and then look at adding a traditional CNC router in the future (if demand arises) for those large wood pieces.

[Mike Lysov]

I would have never bought a laser driven by stepper motors. I did not know their disadvantages over servos for laser cutting until I got one.

[Tim Bateson]

My 2 cents..... When they say the most machine you can afford, That shouldn't mean the most you can afford payments on. If I had taken a loan out to get started, I would have had to fold years ago. The near zero overhead has allowed me to learn at my own pace without the pressure of financing hanging over my head. Not to mention cash flow was more of a trickle, maybe even dripping the first couple years.

[Mike Lysov]

I cannot see why CNC routers are faster than lasers. It really depends on your product size, details you need to cut out and whether you can use a wider bit to do less passes.
If I compare with my products and the CNC router I have had it is not faster than my 280W laser for cutting. In most cases my laser cuts faster than the router I have had. We can compare cutting something of 18mm thick MDF where artwork details does not allow using any bit wider than 3mm. Actually it is not even comparable because laser can cut out details much less than 3mm while with the router you are limited to a bit diameter. Anyway lets assume there are no such small details in the product used for comparison.

On my router I wa doing one pass with 2.8mm depth maximum and feed rate was 3200mm/m, usually even less than 3000mm/m.

So for 18mm thick product I had to do 7 passes. That is 3200/7=less than 460mm/m
Now with the 280W laser I can cut through 18mm thick MDF at 480mm/m rate That's already 5% faster. Plus with the router I had a lot of tabs left on my products that I had to remove and it was taken at least extra 2-3 minutes. Yes, the edge is not square with such a thick material and it is charred but i is just a matter whether you and your customers are ok with it.

[Rich Harman]

I would have never bought a laser driven by stepper motors. I did not know their disadvantages over servos for laser cutting until I got one.

Can you elaborate?