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Thread: Engraving on Black acrylic

  1. #1
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    Engraving on Black acrylic

    Okay, I'm ready to do a graduation announcement for my nephew on black acrylic. It has the school logo, a photo of him, and text. Do I need to invert anything or should it be "normal" engraving. Also, the picture is a color pic, would I be better off changing to gray scale. I'm such a novice!

    Thanks in advance
    Carol
    Carol Barbero (Newbie)
    Epilog Mini 18, 30 Watt

  2. #2
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    Carol,
    I haven't done any engraving on Black Acrylic, but you will need to convert it to grayscale. Are you using photograv or are you manipulating the picture yourself? I am assuming you are engraving on the front since it is black Acryllic. Is that correct? If you are manipulating the photo yourself you may want to look through some of the threads on here on engraving on marble or granite because there is some excellent advice on how to get your photo just right by lightening and darkening different areas.
    John & Alicia Love
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  3. #3
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    You have to invert when engraving on black , the laser engraves all the "black" in the picture.
    Rodney Gold, Toker Bros trophies, Cape Town , South Africa :
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  4. #4
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    Hey Carol.

    You can get more control over the result by converting to 1-bit in Corel-Draw, rather than relying on the Epilog driver to interpret your greyscale.

    In Corel, select your image & choose "Bitmaps/Mode/Black & White (1-bit)..."
    Select the "Stucki" dithering pattern & adjust the slider to tweak the result, you can pan around your image & check the preview.
    Pay attention to where you have black-to-white gradiends or detail in your image, you always have to "juggle" how much to lose during the conversion.

    This method is much better than converting to a greyscale & then having the driver do the dithering ( even though the "Stucki" dithering in the Epilog Driver is very good, for photos you need more control over how the dithering is applied to light & dark, gradients & details etc )

    You can get better results by experimenting with adjustment of brightness & contrast of the image before doing the conversion.

    Good luck!

    Chris.

  5. #5
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    Yes it needs to be inverted. If you decide that you want to remove the background before inverting it, then it has to be black because when you invert it, the black will turn to white and won't engrave.
    Epilog 45w Helix X3/X5 Corel Microflame Generator (flame polisher) Heat Bender


  6. #6
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    Smile

    Thank you all for the advice. I'll give it a try tonight!
    Carol Barbero (Newbie)
    Epilog Mini 18, 30 Watt

  7. #7
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    And make sure to use cast acrylic.
    Brian Robison
    MetalMarkers
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  8. #8
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    Not sure......but I think all colored acrylic is extruded......no one that I bought acrylic from has ever confirmed it......they just say they don't know.

    But the only time it really makes a difference is on clear acrylic.
    Epilog Mini 24 - 45 Watt, Corel Draw X5, Wacom Intuos Tablet, Unengraved HP Laptop, with many more toys to come.....





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  9. #9
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    I've buy extruded acrylic in black.
    I use it all the time as a back piece for my license plates.
    Brian Robison
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  10. #10
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    Burn a piece , cast burns with a crackle and wont drip molten flaming balls , extruded will burn silently and drip molten flaming balls
    Rodney Gold, Toker Bros trophies, Cape Town , South Africa :
    Roland 2300 rotary . 3 x ISEL's ..1m x 500mm CnC .
    Tekcel 1200x2400 router , 900 x 600 60w Shenui laser , 1200 x 800 80w Reci tube Shenhui Laser
    6 x longtai lasers 400x600 60w , 1 x longtai 20w fiber
    2x Gravo manual engravers , Roland 540 large format printer/cutter. CLTT setup
    1600mm hot and cold laminator , 3x Dopag resin dispensers , sandblasting setup, acid etcher

  11. #11
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    Ouch! That's gotta hurt.
    Brian Robison
    MetalMarkers
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  12. #12
    Steve

    Check out Rowmark colorcast acrylics in the Johnson Plastics catalog.
    Mike Null

    St. Louis Laser, Inc.

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  13. #13
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    Quote Originally Posted by Steve Clarkson View Post
    Not sure......but I think all colored acrylic is extruded......no one that I bought acrylic from has ever confirmed it......they just say they don't know.

    But the only time it really makes a difference is on clear acrylic.
    I buy cast colored acrylic from Piedmont Plastics regularly. Just because it is colored doesn't mean it's extruded.
    Epilog Legend EXT36-40watt, Corel X4, Canon iPF8000 44" printer,Photoshop CS6, Ioline plotter, Hotronix Swinger Heat Press, Ricoh GX e3300 Sublimation

  14. #14
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    I have about 2 tons of different coloured acrylic. All of it is cast. I actually don't have any of it which is extruded.
    Epilog 45w Helix X3/X5 Corel Microflame Generator (flame polisher) Heat Bender


  15. #15
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    Degussa who supplys Euro and africa make a huge range of extruded colours and others
    Extruded will stress crack with solvents far more than cast
    Extruded is generally far tighter in thickness tolerance than cast - cast can vary by more than both plus and minus 10-20% over a sheet.
    Rodney Gold, Toker Bros trophies, Cape Town , South Africa :
    Roland 2300 rotary . 3 x ISEL's ..1m x 500mm CnC .
    Tekcel 1200x2400 router , 900 x 600 60w Shenui laser , 1200 x 800 80w Reci tube Shenhui Laser
    6 x longtai lasers 400x600 60w , 1 x longtai 20w fiber
    2x Gravo manual engravers , Roland 540 large format printer/cutter. CLTT setup
    1600mm hot and cold laminator , 3x Dopag resin dispensers , sandblasting setup, acid etcher

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