Release the Kraken! Engraving painted Acrylic

Finished creations
#1

1
14640×3472 1.67 MB
2
24640×3472 2.96 MB
3
34640×3472 2.21 MB

Dear fellow Lightburners,

i recently engraved poylsterene which i sprayed black on one side. The tentacles came out nicely, thus producing some nasty fumes…
The magnet (some with defective vacuum tubes on them) are a quick solution for some warping problems. I have to improve my method of holding my workpiece down. Since one side in engraved and thereby structurally weakened, the polysterene begins to bend. Focus is lost easily and the result is a loss of the workpiece :frowning:
Any ideas about how i can hold things down to the surface?
The finished artwork is glued in a 3d printed frame, painted with rust-alike-paint and then glued on some timberframing i will use for walldecoration.

#2

It looks very nice, also the frames with that rust paint I am impressed by. However, refrain from working with plastic (except acrylic) it is not good for your health nor for the machine.
It’s a bit confusing, in the headline you write acrylic and in the text polystyrene …

#3

I’ve had acrylic and even some 3mm ply go into slack mode in the middle of a job. Acrylic seems to absorb and retain the heat, then send it on to other portions of the job.

For complex, part-filling designs, it’s a tough task to provide support sufficient to avoid distortion. If there are spots within the work that will not be hit with a laser, an under-surface block would be an answer.

I 3D printed a number of “jacks” that have a magnet encased in the base and another encased in the top. The base and top thread on, holding the magnet. The tops are printed with corner cut-outs, edge cut-outs and no cut-outs. The no cut-outs are used under locations that won’t take a laser hit. Each jack can have a magnet over the work, pulling it down if it warps during the cut, or pulling it down if it started warped, as 3mm plywood has.

They aren’t hard drive magnets and they aren’t cheap, but magnets are a must-have for laser work. Please explain how the expired vacuum tubes assist? Eye candy, like having a cat in the frame?

#4

Hello again. I used polysterene (called polystyrol in german).
Yes, i also thought about some 3d printed parts with “cutouts” to hold thing down.

The used vacuumtubes come from my amprepairs and clued to the magnet with epoxy, just for looks. I use them to put notes on metal surfaces. If you are interested in vacum tubes: there are some cheap at ebay in wholesales, especially the uncommon ones.