Hi guys, I could use some help. I not happy with the results I’m getting from this image so I’m hoping someone can offer some advice. I’m trying to engrave our local baseball team logo on a bamboo cutting board. The image was black and white and brought into laserweb and converted to gcode (the colored original image attached). As you can see I have a bunch of lines, extremely dark areas and all in all it looks pretty chard. I do have air assist running as well. Any help would be greatly appreciated.
Hi @Chuck_Comito what speed/power did you use? The image has some very dark colors.
They were mentioning something about updates to a material database lately, but I do not know what version of laserweb they were talking about. I just figured it might be relevant.
@NathanielStenzel materials database is user input, just saved settings for later use.
Used 30mm/sec for dark and 85mm/sec for light and set the power from zero to 50 percent.
Thats seems to high in power or to low in speed. You can always do a second pass, go faster much faster i would say 200 to 300. Also if needed add some brightness to the image
Totally agree with Ariel that the speeds seem too low. I would typically do around 400 (black) 500 (white) with LW3. Can always do a 2nd pass as Ariel mentions. Also, sometimes after cleaning the final job (I used a small fingernail scrubbing brush & water) it will come up much lighter than originally shown.
On another note please post you stp file and images of your conversion here or in the k40 group. I been meaning to ask you for that. 
Should I first convert the image to 1bit black and white or just do what I did with faster speeds? Also, if I change speeds what would you recommend for the slow (dark) speed vs the fast (light) speeds?
@Chuck_Comito As far as I recall from the theory behind black/white speeds that Peter shared, the larger the difference between the black & white the more noticeable the changes between shades of colour should be in the end result (dependant upon material however). Mostly I found that a difference of about 100mm/s (i.e. white speed higher) seemed to give decent colour/shade differentiation in the final job.
@Yuusuf_Sallahuddin_Y right. The black colors would have more time to burn than the white. As long as the white speed and power has the ability to darken then wood slightly at off white colors, it should look great.
On another note, I believe I had asked before if someone could try preheating the surface prior to lasing to make it easier to lase consistently, but I believe I simply got a “too much bother” sort of response. That was a while ago now.
I do lots of bamboo your feed rate is too slow for dark and light
@NathanielStenzel That would be interesting to test. I guess you could test with a heat gun or hair-dryer. What I wonder is how to test “consistency” in that circumstance though, as each piece of wood has different grains (& possibly hardness in different areas) & would make it difficult to get any real consistency due to the inconsistency in the material.
Also of note… Bamboo needs to be sealed after engraving or you will lose any color variations that occured durring the laser engraving process… The black will essentially wash out if exposed to water
Faster speeds for both of these. The non-detailed one was the original processed by laserweb. The better one was pre-processed in gimp to allow more contrast but I used the same speeds. So, light was 350mm/sec, dark was 150mm/sec.
That is practically monocolor. Maybe split the difference on the Gimp modifications if you go that route? I imagine your laser power can be turned down if you go the oher route or your speed could ne turned up, but that is just using logic and no experience. I do how to get some minor experience later though as I end up adding a wood burner with speed control to my cnc. Yes, a wood burner instead of a laser. It may sound crazy, but I figure it should work for images at steady powered variable speed settings. I do not know of someone else doing it, so someone should try it out.
