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Roger Lueck
04-07-2018, 7:22 PM
When converting vector graphics to bit map graphics for engraving using RDWorks v8, there is a perimeter line that surrounds the graphics that were converted to a bitmap image indicating these graphics will be engraved.

For some reason that perimeter line also engraves when the bitmap graphics engrave. How can that perimeter line be changed/deleted so that it does not engrave?

Thank You,
Roger

Kev Williams
04-07-2018, 11:29 PM
Is your engrave mode set for 'cut after engrave' rather than just 'engrave'?

If not, does a good portion of the artwork run up against the perimeter line (aka bounding box)? I've had this happen before at times with every laser, and it was always the horizontal line at the bottom (or top if engraving bottom-up) at the very end of the engraving.

Assuming you're using Corel, try this: when your image is ready to go, hit "view" and go into wireframe view... select the image with the mouse, and note the bounding box---

Now, hit the 'edit bitmap' button at the top, which will park it into CorelPaint for editing... once in Paint, click "image", then "paper size"... below you'll have 'current' and 'new' width and height dimensions, there's up/down selections at the right of the new selections. Click the 'width' button once, or a few times, until you see the white border building up on the sides, then click the 'height' button the same amount of times, then hit "ok"... the image should pop back on screen with a white border around it. Press the "finish editing" button above, "yes" to save, then alt-tab back to Corel where the image with the new border will reside. Note in wireframe mode if the bounding box moved, it should have--

Now, with absolutely no engraving data anywhere near the bounding box, hopefully the laser will engrave the graphics and ignore the box-- like it's supposed to! ;)

Just note that the dimensions as the laser will see them will be of the bounding box, NOT the image itself, so this needs to be taken into account...

John Lifer
04-08-2018, 7:53 AM
Thanks for that Kev, I do things different, very seldom engrave a bitmap, almost always I take 'vector graphic' with a background or objects I want to eliminate, convert to bitmap, depending on the graphic, I use one bit black, gray scale or just leave RGB. Then resample, and do a trace. Usually a high quality, but it doesn't matter a lot, then after working with colors if needed, and the other sliders, let it finish converting and will have background and delete original selected. It may or may not eliminate the full background, but if not, I ungroup and delete unwanted. Use a solid color box placed behind image to insure no white remains.
Your way may be faster, I'll try it.

Roger Lueck
04-14-2018, 11:50 AM
Thanks for the replies John and Kev.

Per John's advice, I discovered that when you convert a vector to bitmap for engraving, it needs to be converted to either greyscale or black and white (best choice) to avoid the "perimeter line" (bounding box) from either engraving or cutting. When converted to CYMK the problem will occur most of the time.

Roger