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Richard Rumancik
10-20-2006, 12:24 PM
Has anyone had experience with using LaserDarc and the colored "bake-on" versions on wood engravings?

The LaserDarc is a black powder that is brushed on and fills in the "pores" of the engraving. The colored version requires a second pass with the laser - I'm not sure how well alignment is maintained but as it is a higher-speed pass maybe it is forgiving if slightly misaligned.

Bruce Volden
10-20-2006, 1:00 PM
Richard,


I just can't get too excited over it, I sometimes hate to do things once let alone the same thing twice!!?? It sounds like this stuff is "basically" a powder coating used in the industries for super toughness. I prefer to mask and spray paint if customers want more color. I do seem to go through lots of colored automotive wax also. My $.02.


Bruce

Nancy Laird
10-20-2006, 1:41 PM
Richard, on wood engravings we use an acrylic paint (artist quality). When the piece comes out of the machine, wax it with a good quality liquid floor wax made for wood floors. That seals the pores and cleans off any flare or soot from your piece. Then just slather the paint over the lasered portion -- we use a battery-operated toothbrush(!) -- and let it dry for a couple of minutes, then lightly remove the paint from the unlasered portions with a damp cloth. You will probably get some residue or film, but that's okay. After the paint is completely dry, (at least a couple of hours--overnight is better,) wax again, and the wax will remove any leftover paint residue or film and give your piece a nice shine, as well as sealing the paint.

Give it a try on some scraps or samples. We do a LOT of name tags, signs, etc. on 1/8" birch ply, which is fairly blonde, and use burnt umber acrylic (Liquitex Basics--available at any Hobby Lobby) for the color fill. The same technique applies to the pen boxes, plaques, etc. that we do. We go through a LOT of wax. (IIRC, the brand is Holland House, available at any major supermarket--just make sure that is the one for wooden floors).

Nancy

Ed Lang
10-23-2006, 12:52 PM
Bruce, would you tell me more about this process. Maybe start a new thread or PM me.

thanks.



Richard,


I just can't get too excited over it, I sometimes hate to do things once let alone the same thing twice!!?? It sounds like this stuff is "basically" a powder coating used in the industries for super toughness. I prefer to mask and spray paint if customers want more color. I do seem to go through lots of colored automotive wax also. My $.02.


Bruce

Lee DeRaud
10-23-2006, 1:15 PM
We do a LOT of name tags, signs, etc. on 1/8" birch ply, which is fairly blonde, and use burnt umber acrylic (Liquitex Basics--available at any Hobby Lobby) for the color fill.The birch ply I've been using ends up almost black in the rastered areas if the settings are right: the laser burns through the light top layer and exposes the darker second layer, plus it chars the glue in between. A quick coat of spray-can shellac seals it. See http://www.sawmillcreek.org/showthread.php?t=32906 for an example (as well as some other discussion on this topic: it comes up about every other month).

Bruce Volden
10-23-2006, 3:12 PM
Bruce, would you tell me more about this process. Maybe start a new thread or PM me.

thanks.



Powdercoating is a process where a powder is electrostatically applied to a metal. The powder itself is almost always a "plastic" based pigment. It can also be a hybrid of plastic and often will be availabe as an epoxy, which is also powdered! It is then baked in an oven until the powder melts, flows, bonds....with the metal and makes an EXTREMELY durable coating!! Powder is available in ANY color or texture or gloss under the sun, to include the crackle or veined looks. The temps required to cure the powder are usually less than 375 F. So I'm thinking that using this stuff and hitting it with a laser beam would make it "bond / adhere" to plaques et el. I don't beleive you would have much luck with making it bond with metal though, as I recall the substrate has to acheive a decent temperature also. Sorry for not getting back to you sooner.


Bruce

Bill Cunningham
11-29-2006, 12:51 AM
I have always considered LaserDark to be a "custom name" for Photocopy Toner... If the wood has been finished, just brush it, and it works..If you run it again, at high speed/low power the toner 'bakes' into the engraving...