Would the GF be able to handle the task of the CNC?

projectinspo

#1

Here’s a really cool project I just saw on Instructables – anyone know if the GF could handle what is being done by the milling bit of the CNC?


#2

The Glowforge can definitely engrave acrylic.
If you search these forums for “signs” you will see some examples of doing exactly this.


#3

You will have no problem, except make sure you buy cast acrylic not extruded. Cast has good contrast when engraved so will light well, extruded has low contrast so will be very subtle.


#4

The key to the sign is “scratching” the acrylic like the router bit so the light is routed out the front of the sign instead of to the top edge. With a mill bit you only get one scratch-pattern. I would suspect you could do really cool effects with a combination of micro-engraving and smoothing (through defocusing the laser) at different depths and angles and patterns to your light source.

Laser cutters seem to be a primary tool of professional sign makers. One forum where they congregate is at the sawmillcreek engravers forum. If you search there you may find ideas and tips.


#5

I have made many acrylic signs as a side business using my Homemade CNC and a friend of mine recently purchased a 10K laser cutter and I got a chance to use it in making a acrylic sign and found that with the laser there is no need to polish the light edge of the sign when cutout and found that when the letters/design is engraved the outer edges are also polished and light transference was much better then I got with my CNC…Can’s wait to get my Glowforge…


#6

Also, if your acrylic sign needs to be larger than what the pro or basic can handle, I found some inspiration on the pass through thread from @syzygy2112 :

To be more specific, a neat workflow from 123D Make is to specify that your material limitations are 12"x20" and it will automatically produce plans with the number of 12x20 sheets needed (maybe mdf?) along with puzzle like tab connectors to put your large stencil back together. then no cnc needed. Just Router.


#7

He used a router to cut the trench for the LEDs as well. That one would take a bit more work on the Glowforge, as you need to figure out the right power setting to blast that depth in the wood, and then if using a natural wood, go back over it and smooth out the spots where grain or knots prevented you from getting full depth.


#8

Since I am not currently doing much production work most everything I make is a one off.
For wood in particular I am expecting to use the glow forge to cut complex grooves (not through cuts). Then use a good old fashioned chisel to remove material inside the lasered area. That way I can get a clean edge, but much more rapid material removal.

Plastic is a little trickier, but even there if you have a dremel you might want to consider a hybrid approach instead of trying to do everything in the laser.


#9

He was working with 3/4" stock for the base, but this kind of project strikes me as a great candidate for laminating a few thinner layers together for the base, maybe even of contrasting species.You could potentially build the skirt the same way, but instead of one piece per side, you could have four layers with a hole in the middle for the Acrylic. By doing it that way, you wouldn’t need to cut a 1/8" deep groove in the base for the LED strip - the top layer could have that slot cut right through it, and the hole he drilled into the side for the wiring could be approximated with strategically placed slots in the middle layer(s). Oh, and those glue-ups would be easy to clamp too, so you could enjoy your frosty beverage in more comfort while waiting for the glue to dry! :grinning:
When all you have is a laser, everything looks like a laser project!


#10

Yes, I’ve done that very project using a laser. The key to it is to use the acrylic that spreads the light from the edge. Other kinds of acrylic won’t work as well.


#11

Yes, Cast acrylic is best for edge lit signs…