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Scott Alberts
02-22-2013, 1:38 PM
Just got my Epilog Mini 30w. It's working great, but was wondering what the best setting is to darken the engraving in wood. I want to see how dark I can get it without color filling it.
Any other tips would be great too.
Thanks guys.

-Scott Alberts

Tim Bateson
02-22-2013, 1:46 PM
Scott, do some searches here. A lot of discussions on the topic. One answer is to laser out of focus. You'll have to experiment for the best color -vs- sharp image.

Glen Monaghan
02-22-2013, 2:45 PM
Some wood inherently darkens with a wide variety of laser settings, while other wood just doesn't seem to get very dark no matter what settings you use, and some (oak comes to mind) is highly variable with parts of the grain getting fairly dark and the alternate grain changing very little.

When going for darker coloring, I generally go slower and lower power. My thought is that higher powers tend to vaporize the wood and higher speeds provide limited dwell time to heat the wood. I think of darkening in terms of caramelizing any sap in the wood or toasting the wood fibers, and that means lower heat and longer "soak" time in order to bring about the change in color without vaporizing all the darkened material, hence slow and low...

-Glen Monaghan

Scott Alberts
02-22-2013, 2:58 PM
Thanks Glen. That makes sense.

Richard Coers
02-22-2013, 3:32 PM
What species of wood? Cherry or walnut should be used for really dark burns.

Scott Alberts
02-22-2013, 3:36 PM
Using Baltic Birch.

Ross Moshinsky
02-22-2013, 3:55 PM
Increasing the DPI typically works.

Michael Kowalczyk
02-22-2013, 6:02 PM
I was doing 2 different runs last night and both were with our 3mm Genuine Baltic Birch. One had a gold glitter material with an adhesive back that I pressed on by hand and then rolled with pressure using a "J" roller and the second one was 3mm with a double coat of clear poly (front and back).
I do a dual pass to get a clean darker burn. First pass at 100 power 35% Velocity (speed) Then a 2nd pass at 100 power and 50% Velocity with a .020" Z offset. 1st pass is engrave only then the 2nd pass has engrave (black), mark(red), cut inner (blue) pieces and then cut (desert blue) perimeter Sent pictures to my potential customer and he replied WOW!!! and wants us to quote 10,000 to 20,000 pieces.:)

Dan Hintz
02-22-2013, 6:14 PM
When going for darker coloring, I generally go slower and lower power. My thought is that higher powers tend to vaporize the wood and higher speeds provide limited dwell time to heat the wood. I think of darkening in terms of caramelizing any sap in the wood or toasting the wood fibers, and that means lower heat and longer "soak" time in order to bring about the change in color without vaporizing all the darkened material, hence slow and low...

Glen, an excellent description and right on the money.

Tim Bateson
02-22-2013, 6:20 PM
...generally go slower and lower power...

True, but time is money.

Glen Monaghan
02-22-2013, 7:26 PM
True, but time is money.

Well, yeah, but cost wasn't the issue being addressed. The OP didn't say whether his new machine is for hobby or business, just wanted to know how to get darker engravings in wood. My experience is that I get the most darkening by going slower and lower power. When I try to go faster, lower power can't darken as much so I up the power but then I get more material removed and still don't get as much darkening. Hence, lower and slower.

If money is your issue, then you have to determine what is acceptable coloration vs time (ie, if you run the job at a speed that you find adequately profitable, can you get both a depth and a color that your customer finds acceptable and worth the cost?). Alternatively, is there another process that is faster and/or cheaper, such as using any of a number of color fill methods, to get the color you need. For example, on a couple of jobs where I wasn't getting enough color but wasn't willing to spend more time engraving, I filled the engraving with a black pigmented filler (aka shoe polish!) and then used a hot air gun to melt it into the grain to develop the contrast I needed (doesn't work with some -porous- woods because the color leaches out through the wood pores). Other threads mention powder coat paint, laser darkening sprays, etc. Personally, I see those materials as extra expense and the extra handling also falls under "time is money", so what are ya gonna do?

-Glen Monaghan

Tim Bateson
02-22-2013, 10:08 PM
I believe both of our methods produce comparable results. As for color fill, Yes I do use that often as no method can get the colorization some customers wish to see and as you stated earlier some grains and some wood will never burn to satisfaction.

George Carlson
02-23-2013, 9:40 PM
On my machine I can do a "cut after engraving". So I make a quick shallow cut which really makes lettering stand out. The residue from the cut makes the engraved part darker as well.

Ben Halop
07-22-2013, 12:28 PM
I know this thread is a few months old but I've found with wood when you wanna run a higher speed setting, for a "branded" look I run at normal speed/power but have the laser roughly .75" out of focus. However this will not be as deep as standard wood etching. If you don't mind doing two passes I have found this works equally well running it normal first, dropping the table .75" and running a second pass, then it will come out deep and dark :)