A laser can provide incredible detail and precision, and also ensure a minimum of wasted material. But because it cuts by heat (i.e.: burning), only relatively thin layers of wood can be laser cut.

CNC engravingwood

Only having used this tool a couple of times, I am completely satisfied with it's performance. I have used the bit to flush trim a few patterns in walnut and white oak. This bit moved right through the wood. The cut was very smooth. I am also happy that I will be able to turn / swap out the cutters.

CNC engravingdesign

However, because the material is removed by a spinning cutter head rather than burning away by the width of the laser beam, a laser generally allows you to get more detail and sharper edges. That is because the cutting or engraving is just the width of the laser beam, and because a spinning bit can sometimes “tear out” wood fibers around where it is cutting. Also, for interlocking pieces - such as in a puzzle or the pair of coasters above - laser cut pieces would generally fit together more snugly and can be cut via just “drawing the lines”; trying to do that with a CNC would either leave a much larger border between the pieces, or require cutting individual pieces from much larger stock if a snug fit is desired.

This is an investment! That being said, if you only doing one slab, I would recommend DIY build or having someone professionally flatten your project. I would hazard a guess that you would be saving for a fifth of the cost of this rig. I bought the dust shield with vacuum hose attachment and was disappointed on a few levels. Firstly, it's a gimmick that falls short of its intended purpose and although it may cut down a little of the waste being scattered in the shop, it does not work as advertised. Do your slab flattening outside or you'llbe vacuuming for days. Secondly the hose port fit is not standard for any shop vac, so you'll be needing some type of adapter. As for the router sled itself, the build is sturdy, and it does work as intended. However there is the minimal clearance issue. Even at its lowest setting, I still had to raise the work piece as the plunge depth of routers are limited. Also expect to clear debris (constantly) from wheel path as it collects and will hinder the smoorh and level tracking of the wheels Overall, it works. But I'm thinking I should have opted for the bearing rail system. I gave it 3 stars because that's where it falls in the overall rating. Average! These are my opinions from my experience. Your millage may vary. If I could send it back without the hassle. I probably would. I don't have the box, and the return policy says everything has to be in original unused condition, which is impossible after use.

When using a laser with wood, there are really just two “depths” you can set the laser to: engrave, or cut all the way through. You cannot use a laser to create detailed multi-depth cuts, except via stacking those layers on top of each other after the laser has cut them.

Cnc engravingmachine

Lasers always leaves telltale signs in wood: since a laser does its work with heat, there will be burn marks along the edges of whatever was cut. And similarly, a laser does its engraving into wood items via burning, so that engraving is always burned. This isn’t the burning you see of a log in the fireplace, but rather, because of the very controlled power and positioning of a laser, just a potentially modest darkening of the material around the edges. That is, the engraving done by a laser will never be the same color as the natural wood.

The tray part of this 2.5” deep key tray was cut out via a CNC; a laser could not remove the interior material to a precise depth, nor cleanly shape the vertical interior or exterior sides.

CNC EngravingMachine for Wood

I’ve often been asked if the engraved coasters I make are “laser cut” - they are not - which brings me to today’s topic: how to tell if something is cut or engraved with a laser (vs. cut or engraved with a CNC).

Do you have some cool laser- or CNC-made products to share? Or does this trigger other questions in how to tell the difference, or when to use one approach vs. the other? I’d love to hear your thoughts on the topic.

CNC engravingmetal

Incredible detail in thin wood, but note the discoloration around the edges, especially at the corners where the laser lingered slightly longer.

Cutting or CNCing the wood uses a rotating cutter head to remove material from a solid piece of wood. The three main advantages of this as compared to a laser are:

The base of this single-digit Nixie clock was made via CNC, with engraving done by a very small engraving bit, and the cavities for the buttons - that had to be of a precise depth into this 3/4” thick walnut - made with a larger cutting tool.

CNC EngravingTool

CNC engravingnear me

I had previously been doing all my slab flattening on a home made sled. It worked ok and it got the job done, but it had many limitations, some of which I didn't even realize until I started using the SpeTool sled. The first issue was that it had too much flex in the wood rails and would sag when I tried flatting slabs larger than about 20" wide. The second issue was the mess it made in the shop. It was actually so bad that I would have to use it outside. The biggest draw back however, wasn't realized until I started using the SpeTool sled. With the SpeTool sled I was able to work the router with the grain down the long side of the Slab This was something that I couldn't really do with my homemade sled. Working with the grain produces a smoother surface and is less work in my opinion. Then when you add in the dust collection, I was able to work in my shop again. Now I am not going to say you won't need to vacuum when you are done, but the mess is drastically less than with no dust collection. Also, the aluminum rails are much stiffer than my wood ones and don't flex nearly as much over larger spans. I would absolutely put this kit at the top of my list if I was setting a small garage shop up for slab flattening. Rob @ RM Woodcraft llc

These bunny “canvases” - which have not yet been painted by artist Jun Yang - are of 1/2” thick baltic birch plywood, far too thick to cut by laser.

Receive notifications when new blog entries are posted, as well as periodic newsletters of upcoming shows and new products. You can unsubscribe at any time.

To sum up the properties of the results: laser engraving gives you incredible detail albeit with some discoloration, while CNC engraving gives you depth. And laser cutting gives you very clean vertical lines but also with discoloration, and limited to thin materials, while CNC cutting allows you to work through thick materials and to cut to very specific depths to form truly three dimensional objects.

And just like the multi-layer laser-cut map above, we can construct multi-layer CNC pieces when the wood is much thicker, such as this lion, one of the more intricate and involved art pieces I’ve done so far:

Though laser engraving might also have been an option to engrave the messages on these coasters, I liked the more natural appearance and depth provided by CNC engraving. The cutting tool was basically shaped like a cone; the deeper that bit goes into the wood, the wider the line. You can read up more here on some of the planning involved in CNC engraving.