PDA

View Full Version : Set up advice for Raster on Wood



Tim Earling
06-16-2012, 12:00 PM
Hello,
I am engraving (rastering) a map on 1/2" Pine Wood. The size of the map will be 24 wide x 18 width (the full size of my laser bed - Epilog Helix).
I have never done a raster this big and was wondering if I could get some suggestions on my settings. My artwork is simple black and white, no color in the design.

Couple concerns I have is

1. Should I convert my Corel Art work to a bitmap image (if so, should it be 200 or 300 DPI)
2. The settings I normally use are 400 DPI at 35 speed and 100 power (the suggested Epilog settings)
3. Is there any way I can calculate the time it will take to raster a project this large

Thanks for your input.

Chuck Stone
06-16-2012, 1:05 PM
If you're doing a bitmap image:
the first suggestion I would make is to split that image up into tiles. That way you can
engrave each section separately. (separate layers/colors?) Nothing piles on the time like
engraving four or five dots on each outside edge and skipping over the entire middle section
(Maine and Washington?)

(if I understand correctly..)
Unless you're doing just hairlines/vector the software is already going to send a bitmap,
so I don't think you need to worry about that so much. But make sure your image is mostly
pure white (RGB). Otherwise it will engrave every square inch. Almost white and black look
identical when it comes to engraving. White doesn't engrave.. everything else does.

Tim Earling
06-16-2012, 1:11 PM
Thanks Chuck,
How do I split the image up into tiles? I have coreldraw x3

Joe Pelonio
06-16-2012, 2:50 PM
For a nice clean image without having to sand, I would finish it first with some kind of clear poly, I like Minwax. Otherwise, especially with pine, you will get bleeding of char/smoke around the edges of the details. Please share how long it takes
when done, I'm guessing 60-90 minutes. On a job that big on wood you get sooty smoke on the lenses/mirrors and if you do use the tile method I suggest cleaning before running each section. If you do it all at once, press pause and clean or stop completely 1/2 way thru to clean, then add a big bitmap all white with white outlines over the part you already did except for a slight overlap area and send the job again to do the rest. That's a good technique to learn anyway, and
it may be a good idea to practice it on a smaller piece using scraps.

Mike Null
06-16-2012, 4:06 PM
And after you finish you will probably vow never to engrave pine again.

Steven Cox
06-16-2012, 8:18 PM
And after you finish you will probably vow never to engrave pine again.

I find Pine is OK BUT you need to be very selective on the piece you use by avoiding pieces with wide sap areas. A closed tight grain pattern with minimal knots works best for me.

Bill Cunningham
06-17-2012, 1:58 PM
If your image is 300 dpi, engrave it at 300, or multiples of 300 like 600, or 1200..Not 400.. I usually engrave photos at 600.. you get a darker image.

Peter Meacham
06-18-2012, 8:20 AM
Tim

Do you need to raster a map instead of vector engraving; how much detail is in the map? Maybe you could post the drawing for some additional advice from the members.

Pete

Khalid Nazim
06-18-2012, 10:24 AM
Hi Joe, can you elaborate on what would "sending a big white bitmap" do after the engraving is finished? I am not familiar with this.

Tim Earling
08-02-2012, 11:00 AM
Thanks for all the advice on this. I did it twice, once using Pine Wood and the using Baltic Birch 1/8" thick). The Pine Wood came out bad and the Baltic Birch was perfect. I did two passes on the Baltic Birch piece. The second pass I did on a lower power and slightly higher speed - it cleaned up the map beautifully.
I will stay away from using Pine Wood for similar projects - Baltic Birch is a great wood to raster on.

George M. Perzel
08-02-2012, 6:32 PM
Sorry-don't agree. Baltic birch is not a great engraving medium. Contrast is poor and, as you said, needs two passes. Believe it or nor, one of the best mediums for raster engraving is luan ply-make sure its luan and not meranti (yellowish) or one of the other recent sunstitutes. I do photos on luan-great for holding detail and superior contrast at fast speeds.
Best Regards,
George
Laserarts