What wood does everyone use for laser cut prototypes for parts that will ultimately be cut out of aluminum plate or polycarbonate? 1/4” birch plywood? Other?
Cheap floor underlayment. Or for thicker, whatever plywood is cheap at Lowe’s.
1 Like
There’s a decent bit of discussion in this thread from a few weeks ago around materials for prototyping on a laser
We used to go to hardware stores for it, but a lot of the Baltic birch is warped, or just doesn’t cut well. It works, but it’s annoying sometimes.
I’ve had pretty good luck with Makerstock. Their prices are reasonable. Little annoyed to pay shipping on sheets of plywood, but it is what it is. Most laser cutters don’t have huge build volumes, so you can get small sheets.
Thanks! That’s just what I was looking for. I had spotted that thread, but didn’t read far enough to get to the materials part.
Yeah - be careful. “Birch” plywood isn’t baltic birch. It’s usually plywood with a cheap birch veneer on the outside.
If it doesn’t have 13 layers, it isn’t proper baltic birch. But for prototyping, you don’t need baltic birch.
1 Like
We use 1/8 or 1/4 MDF
It’s super cheap, cuts well on the cnc router and is nice to do a test cut on a part before we commit to polycarbonate or metal
1 Like
We don’t have a laser, just a shapeoko 5. Our tests with wood were abismal. We have had great success with 1/4" hdpe. Yes it’s more expensive. That’s the only downside.
It holds bearings, is rigid enough and can be reinforced if needed, can be drilled easily for new or forgotten holes, and cuts fast - we run 100 ipm with 1/8 or 7/32 2 flute endmill dropping 0.050" per pass.
Plus The kids learn the tool they’ll use for aluminum in the process.
And if the proto is good enough, take it to competition, it holds up well.
0.25x48x96 $140
0.125x48x96 $70
1 Like
We have had pretty good look with Home Depot SandePly which is pretty cheap and laser cuts easily. Maybe not quite as strong as Baltic Birch, but its cheap and more than adequate for many prototype jobs. We pay about $30/sheet at 5.2mm (approx 1/4") for it in my area.
I never had access to a laser cutter nor a router, but when prototyping, the point isn’t to make something fully robust, just to figure out a geometry that works. Use dimensional lumber when that makes sense, otherwise regular old plywood, thickness determined by whatever the load is going to be and what’s on hand. Once the geometry is figured out, start working with higher quality materials to improve repeatability and robustness.
Sometimes, you may go back to the less expensive materials. In 2017 STEAMworks, we prototyped our gear intake slide out of surplus corrugated plastic signs about mosquito control. After we had the geometry, we made it in polycarbonate, which turned out to have a higher coefficient of friction. After trying several other materials, we went back to corrugated plastic, though we bought new stuff rather than using discarded signage.
2 Likes
Agreed. The robustness may surprise you though. Because it held up so well during practice sessions, we considered not replacing our el cheapo prototype belly pan (we ended up doing so just before our Regional).
$6.33 at our Lowes.
https://www.lowes.com/pd/1-4-in-Lauan-Plywood-Application-as-2-x-2/1000068901