I wanted to design a decorative front license plate for an electric car. Embarrassingly this was my 4th attempt at making this. Every way I’ve tried to paint acrylic has come out looking horribly, so I finally decided to just use more material and do acrylic on acrylic.
This is white PG medium acrylic cut to the shape of a license plate and engraved with the design. Then I cut the same design from PG blue acrylic, and each of the pieces fits exactly into the engraving, which made lining everything up automatic and held everything in place while the glue dried.
I have some of that and have used it to make a few things.
But I want to make some license plates and unfortunately it’s not good for that:
The $7.50 sheets are only 12" wide while a license plate or plate frame are a minimum of 12" wide. Even with lid calibration, Glowforge alignment isn’t good enough to include the edge of the material in a design and have it come out right. I’d need the 12x24 sheets yet only be able to cut a single plate or frame from the entire sheet (12.5 + 12.5 > 24) making it $23 in materials for a single license plate that retails for $5-10…
The color doesn’t come out clean when you engrave those. The dust from the colored top layer gets blown into the white core layer that’s being exposed, and you end up with a speckled interior instead of nice solid colors.
Check out the white text on these hang tags I printed from Inventables color-on-white acrylic. Look closely at the text on the red one. You can see that it looks almost pink, because there’s a lot of red dust trapped in the white text from the engraving process. It does not come out even with vigorous scrubbing with a toothbrush or with being sprayed by air duster cans.
I was really hoping there’d be a way for me to make license plates for other people with my Glowforge, and the only way to do so that comes out looking professional so far is with acrylic designs glued to acrylic, which is somewhat labor-intensive and uses a lot of materials still.
i haven’t done it, but i’ve seen others say that running a very low-power second pass will clean out any of the red dust by removing a very thin layer on just the white area.
beyond the issues you talked about, i think that material has another negative for long-term use as a license plate. you’ll need to make sure it’s UV safe or it may fade. not all colored acrylic is meant for outdoor use in direct sunlight.
I ran into this exact same problem…only with different sizing. Making a 8 x 6" award out of an 8 x 12" piece of two-tone. Technically, I should have been able to get two awards out of one sheet, but because the measurements were so exacting, I had to resign myself to cutting one per sheet.
The two tone stuff is horrible from a smelll perspective…almost toxic. I won’t mess with it again. I agree the dust does not make it clean. I wish it were better!
I don’t know if this is where this needs to be, but it is related to this very issue.
Inventables website actually suggests that the laser be set to engrave backwards on two-color acrylic, to prevent this very thing.
Is there anything in the future of GF that may address that issue? Is there a way that I have not been able to find on my own, that would allow the engrave feature to be set to engrave toward the airflow if the fan, so that the smoke particles won’t become embedded in the warm, softer areas that have just been engraved?
