My first attempt at the edge-lit night sky map! Thank you to all the folks who posted on this topic. Your advice and experience helped me a lot.
This is cut/engraved on proof grade medium clear acrylic using SD graphics settings with variable power. The diameter is 9 inches and the height is 11 inches with about 0.5 inches hidden in the LED base. The SVG was filled using a gradient and exported as a PNG file. The design was flipped horizontally so the engrave would be on the back side.
Some colors definitely make the map pop and are very bright at the bottom (e.g., blue at highest and lowest setting). The LED light intensity can be decreased to compensate but over all I am happy the way it turned out.
Things I would do differently next time: Increase the gradient (currently 80-100% to may be 60-100%), reduce the diameter to 7 inches and add a black rubber band as a washer to hold the acrylic flush to the base. Right now it kind of wobbles because the slot is slightly larger than 3mm. I think the base bottom can be popped open (has anyone tried this?); it might help to slip the rubber washer so its not visible from the top, reduce the thickness of the lines for the constellations, increase the font size and use 20% grayscale.
Also based on other comments and posts, I washed the acrylic with dishwashing soap to remove the small masking tape pieces. I used rubber gloves to prevent finger prints on the acrylic and they really helped with removing stubborn/tiny pieces of masking tape; just rubbing over the acrylic with gloves helped.
Looks Great!
Looks pretty big too. Is that 8" diameter?
Did you (or anyone reading this) test to see how big you can go with the layout with that type of LED base?
I’d like to make something big for our front window, but am afraid the top or sides wouldn’t get enough of the LED light.
Your sky map is great. I don’t ever seem to be able to get the entire thing lit correctly.
Thanks for the tip on the rubber gloves I had not thought that.
Yes, 8" diameter. I pointed the lit base to a wall and measured the distance at which the light beam began to fade or become unfocussed (~about 11 inches).
There were some posts with a rectangular acrylic sheet and the light seems to pass thru to the horizontal edges (eyeballing from the image it seems to extend about 5" on either side of the LED base).
You could use LED strips all along the four edges if you want to make a large window (door frame?) . And if using a GlowForge, the max width you would have to worry about is 20", which I think is doable with LED strips on each horizontal edge.
Could this be an issue with the LED base itself? The LED base I used is very bright; the map lit up the whole room. The pics don’t fully capture the brightness.
I just checked and I did not use the same type of LED Base you have listed above. So next time I try one I’ll give those a try. There are 3 really good ideas in this thread 1. the rubber, 2. the rubber gloves
3. Different LED Display found another one 4. using gradient. Thanks for sharing.
Just a note of caution: the gradient needs more trial and error. Today I tried to push the gradient even steeper and it did not work at all. Only half the design engraved.
I think the approach to tackle uneven brightness will vary from design to design. If the design elements can be “layered” with different color fills then you may not need a gradient. Each color can be engraved at an increasing power setting (shallow to deeper engraving). Just arrange the elements such that the deepest engraved design element is the furthest from the base.
Also the uneven brightness seems to affect the bottom center portion of the design most, about 2 inches from the base. Any design element at that height should be the shallowest engrave (low power + high speed).
