What I’m looking for is something around 1/8" thin, laser cuttable, and preferably in matte colors.
I’ve considered acrylic, but the cost becomes prohibitive on small pieces, and the large pieces are very expensive to ship. I can buy it from a local plastics company for a little over $100 / full sheet, 4 week lead times.
I don’t particularly need it to be plastic, but it needs some water resistance especially on edges and either remain the same color when lasered or a nice contrast, so something like melamine is pretty much out.
Is there anything else out there? Or is cast acrylic sheet really my only hope?
Cheaper is relative. Pvc can cost little money but also eat your Glowforge! you can find inexpensive sources of acrylic, but find that it is extruded. You might call about to a shop that makes big plastic signs etc and ask for a recommendation or even what they do with their scrap.
This - there are signs stores in every mid-sized or larger town and if you’re looking for small pieces they may be thrilled to pass it on to you.
OTOH wood can have “some water resistance” with a spray coat of sealer. I’d suggest doing a test of all possible materials, figure out what you really want to use, and then find a good source at your price point.
That was definitely the most interesting part of @rbtdanforth 's suggestion and definitely something I’m going to try. After all, much of what I’d need it for is 5x8. I would like consistency though, so we’ll see!
Yes wood is by far the cheapest and easiest to source locally, but would require the most “finishing”. Acrylic is so advantageous because if well desired, it’s basically cut, peel, assemble, touch of glue.
I think they are actually 3mm sheets (0.118"), so it’s not really 25% plus or minus.
I suspect this is basically the same acrylic you’re going to find anywhere, but if it doesn’t work for you, there are other places. If you search the forum for acrylic sources, you’ll find lots of options. Some are pricier, but have cheaper shipping, so you need to shop around.