Benbox Laser Machines/CO2 Lasers/3D Printers

Good answer Zax. I too originally thought closer=better. I've played with distance/focus on my 2 machines running different diodes with the 3 element lens and found approx. 3 1/2" front of lens to surface of material to work well for me. I can't go any further away with current mounting. Small fan definitely helps...YMMV

It's more how much power can the mosfet dissipate. 2 to 2 1/2 watt diodes with built in current limiting should work fine. Our diodes duty cycle isn't 100% so that keeps thermal problems down. Anything larger than that, use the PWM output with an outboard ccontroller.

I'm sure I read it here somewhere, after focus, I put a blob of hot melt glue where the lens threads meet the holder, leaving the spring in. Seems to hold nicely and easy to remove.

I use a lot of the 3mm birch plywood (from eBay). I was never pleased with grayscale on this material, even sanded smooth with 320grit. I guess I never liked the "brown" look or the steaking at light shades. I fall back to using dither at 254ppi (.1mm). I use the bitmap dithering in Photoshop. It still takes many trial burns to even get that looking good. Sorry I don't have any secret formula for you. Just keep experimenting.

If the image is all raster, then I just export it as a jpg at 100% quality. Sounds like you will have to either use grayscale or dither.  You will have to do a bunch of experimenting to get the different parts of the image to look close to each other. Here, Inkscape doesn't enter into the picture conversion. Inkscape and dxf are for vector drawings, this is bitmap or raster.

I typically take 1" square samples of the final image and burn them to determine the "power" setting. Since you will be putting together a "collage" from different images, you may have to do this for each part. You could either burn each part separately or adjust the "gray level" of each part to match.

What you see on your computer monitor is not what you will end up with on wood, trust me.

Nice work! Like I said earlier, I find the religious "engravings" to be the most popular. If you search for "engravings religious" there are quite a few dating back to the late1400s to 1500s. Those artists were so talented.

I have no secrets for my lasering. In fact, being retired, I do all my work for free. The hobby keeps my mind extremely busy, between the electronics, mechanics and actual art. I'm currently running exhaust ductwork for a second engraver. Both use the Openbuilds ACRO frames.

Here's kind of how I do things. Regarding raster line engraving, if it's smaller than 8"X10" (approx A4), I will prepare my artwork at 254ppi (.1mm resolution) and engrave the same (most of the time). 8X10 (A4) usually is done at 167ppi (.15mm resolution). I prepare the artwork in Photoshop. Using the levels, black and white, posterization and smart sharpen adjustments, I get it down to just 2 colors, black and white. I might have to do some tweaking, erasing or pencilling in local areas.

For pictures with a lot of gray levels, I do similar tweaking as before but usually reduce the total number of gray levels. Then I use the bitmap diffusion dither in PS at 254ppi. I use PS CS5 which is circa 2010. I suppose the same could be done in Corel Draw of Gimp but never played with those softwares.

As always, my trash can is full every week with experiments and mistakes. The one I seem to do more than I like is forgetting to plug the laptop in and having the battery go dead in the middle of an engraving.

The font size increase is perfect. Thank you.

I guess I like your experiments. I ordered 4 packages from Japan off ebay. Thanks for the idea. Maybe bond the gold side to card stock to stiffen it up a tad.