Tools/Glowforge/Settings

Glowforge settings for various materials... put the "best" settings near the top of each table.

Acrylic

3mm clear acrylic

Glowforge “proofgrade” cut setting is speed 147, full power.

If you tell a box generator that the kerf is 0.2mm, you get tabs that you can assemble, although you have to be careful not to crack the acrylic when you do it. Pieces cut that way will hold together for light use (eg miniature display shelves), without glue.

Plywood

3mm Baltic birch from Commonwealth Plywood, late 2018 (actually 1/8 in, 3.16mm)

Mostly tested in early 2019 with a fairly new tube, in very dry winter conditions.

Looks like this material needs a light hand. All of the initial set of tests left significant smoke stains on the top, and many on the bottom. IIRC, cutting a long line at full/150 results in a flame following the laser.

Material tends to warp slightly and needs to be held flat on the bed using magnets or whatever.

Cutting

Tight corners at high speeds end up looking like there are little round holes drilled at each corner. Looks like it hits the laser and then starts moving, rather than say ramping up the laser as the actual cutting head motion ramps up. Maybe not true any more in 2025?

For long straight or gently curved cuts where start points and corners aren't an issue, high speed is in order. For corners and start points, 150 with reduced power.

Power Speed Focus depth Shape Results
Full 174 3mm Many These are jbash’s standard plywood setting, used for a long time on many shapes as of 2025-07-15. Was using 184 for a long ime, but got some failures near material edges. Faster speeds definitely too prone to fail with mild focus issues or “bad luck”.
Full 200 0.13in Tabbed box Seems reliable if the material is flat on the bed. Some staining on top and bottom, maybe 0.5mm rounding at corners probably due to start/stop time. Staining seems reduced if you put a damp paper towel under the plywood.
80 150 0.13in ~1.1cm sq Good corners, some staining on top, minimal on bottom. This is the lowest power tested so far. Could probably use even lower power and still get good corners.
Full 250 0.13in ? Had this listed as best speed based on cutting 1cm square, but does not reliably penetrate with larger project. May want to retest these faster speeds with more attention to keeping the plywood flat.
Full 220 0.13in ? Still doesn't penetrate reliably, at least on shorter segments (cut out a Penrose tiling and didn't get all the tiles out). Tried with dampened plywood; didn't seem to reduce staining much.
100 150 0.13in ~1.1cm sq Good corners, more staining than at power 90
90 150 0.13in ~1.1cm sq Good corners, more staining than at power 85.
85 150 0.13in ~1.1cm sq Good corners, slightly more staining than at power 80.
Full 150 0.13in ~1.1cm sq Glowforge standard setting for Proofgrade basswood ply. Bad staining on top, major "blowthrough" staining below.
Kerfs and dimensions

In general, telling any box generator that the kerf is 0.2mm seems to create tabs that you can get together with a mallet and will hold together with no glue… without cracking the material. Measurements following were from test pieces early in the game.

Using Full/200 with no backing, a square that Inkscape says is 10mm cuts out at 9.82 x 9.85 by the caliper, and left about a 10.1mm hole. An adjacent 20mm square is 19.85 x 19.86. The hole it came out of is maybe 20.2.

So the kerf is about 0.25 to 0.3mm...

18 evenly spaced cuts across a long skinny 10x200mm rectangle are nominally 10.53, and actually most of them are between 10.35 and 10.4, averaging maybe 10.38. The ones on the ends are smaller, roughly 10.1 and 10.2.

For tabs, a slot with a "geometric" width of 2.78mm will accept a tab of the plywood, but is quite snug. Everything up to 2.80 is definitely snug. 2.81mm would probably be good for gluing, and 2.82 and 2.83 are also acceptable fits. 28.4 begins to be loose.

A slot nominally 20mm long will accept a tab nominally 20.15 long, and it seems like a good fit.

A nominal 3.10mm tab extends above the surface on the "back" of the material, but would easily sand off; 3.05 is below the surface.

Scoring

20/175 produces a solid, dark score line about as thick as a solid pencil mark and visibly cut into the material. Areas with dense scored patterns appear dark overall. Tested with a fractal pattern on the "Sita box" project.

Engraving

Heat appears to build up as engrave lines overlap, so there's less burning and staining with multiple light passes than with one strong pass. Response is unsurprisingly nonlinear.

All these tests are at 450LPI ("HD" per Glowforge). For solid areas, it might be possible to do more in one pass by reducing the LPI to cut down on line overlap and heat buildup.

Power Speed LPI Passes Focus depth Shape Depth Notes
30 600 90/mm 1 0.13in ~1.1cm sq shallow Well defined light-brown text, not noticeably deep
30 600 450 2 0.13in ~1.1cm sq 0.97mm Staining significant but less than in 1-pass engraves.
45 550 450 1 0.13in ~1.1cm sq 0.75-0.8? Fairly similar to 50/600
40 500 450 1 0.13in ~1.1cm sq 0.8mm Staining less than at 40/400, but still significant
50 600 450 1 0.13in ~1.1cm sq 0.74mm A bit more staining than even at 40/500; apparently lower power matters for engraving.
40 400 450 1 0.13in ~1.1cm sq 1.46mm Still considerable staining, perhaps less than at 51/400.
51 400 450 1 0.13in ~1.1cm sq 1.8mm Much smoke and staining, "tarry" deposit at bottom of engrave. Significant burning near long side where engrave started.
100 400 225 1 0.13in ~1.1cm circle 1.8mm Fit a 1.8mm tall magnet in the hole and it sat flush. Much smoke and staining, "tarry" deposit at bottom of engrave.
25 400 225 6 0.13in ~1.1cm circle 2mm Fit a 1.8mm tall magnet in the hole and it sat slightly under the surface. minimal staining.

Ikea Frame Backing

Cut

Power Speed Passes Focus depth Shape Notes
Full 175 2 0.13in pendant press Worked well - cut cleanly through it all (with smooth side on top)
Full 200 1 0.13in pendant press Cut through the solid part and part-way through the mat at the bottom
Full 170 1 0.13in ~2.5cm circle Cut through the solid part and part-way through the mat at the bottom
Full 200 2 2.75mm man. 4mm screw hole Cut cleanly, minimal staining
Full 220 2 2.75mm man. tabbed box First and second passes in separate runs because of mistake. First pass did not penetrate. Second may have, but I didn’t realize how sticky the material was. Did third pass with focus adjusted to 2mm; parts then cleanly separated. Minimal staining.

didn’t see much of a difference between Full/200 and Full/170 - ended up with usuable parts, but had to manually trim them. maybe try Full/200 with 2 passes next time?

Branches

Cut

Power Speed Passes Focus depth Shape Depth Notes
75 150 3 0.13in ~2.5cm circle 7mm Nice cut, minor staining.
75 200 3 0.13in ~2.5cm circle 6mm c ut pretty well at 6mm, didn’t quite make it all the way through after about 7mm
80 150 3 0.13in ~2.5cm circle 8.5mm c ut through maybe 7mm, slight staining.
90 100 3 0.13in ~2.5cm circle 8.5mm M ajor charring of the wood. did manage to burn through, but wasn’t usable.
80 150 4 0.13in ~2.5cm circle 8.5mm c ut through maybe 8mm, slight staining.

Engrave

Power Speed LPI Passes Focus depth Shape Depth Notes
50 350 270 1 0.13in ~1.1cm circle 2mm slightly deeper than the 40/400/225 2 passes. bit more staining.
25 400 225 3 0.13in ~1.1cm circle 1mm Cut ~1mm deep hole. minimal staining. The core didn’t cut as deep, so needed a sight amount of carving to clear it out, but easy to do…
40 400 225 2 0.13in ~1.1cm circle 2mm decent depth, minimal staining
50 600 225 1 0.2in ~2.5cm circl 1mm cut maybe 1mm deep. minimal staining
full 1000 225 1 0.2in ~2.5cm circl 1mm heavy staining, uneven cut (deeper on one side), slightly oblong hole.
50 500 225 2 0.2in ~2.5cm circl 2mm minimal staining, 2mm deep

Score

Power Speed Passes Focus depth Shape Notes
10 150 1 0.13in Celtic Knot Seemed lighter than 10/200?
20 150 1 0.13in Celtic Knot Pretty good
10 200 1 0.13in Celtic Knot OK, but not quite as deep as I wanted

Stamp Rubber

Orange-red stamp rubber from Amazon, 2.3mm

https://www.amazon.ca/gp/product/B017IHVSLM/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

This material engraves without odor generates a lot of ash.

A quick wash followed by 5 minutes in water with soap in the ultrasonic cleaner cleaned up 10pt text, but 10 minutes might have been better.

Engrave

Power Speed LPI Passes Focus depth Shape Depth Notes
100 300 135/cm 2 2.3mm Blue’s logo stamp. 1.5mm? Used “vary power” with minimum of 100 for this monochrome cut.
50 400 135/cm 2 auto Address stamp, 10pt Arial black. 1mm? Early in machine’s life. Was usable but really too shallow. Numbers may not be right; GF app lost my settings...
50 350 135/cm 2 2.3mm Blue’s logo stamp. 0.55mm Too shallow, cut about 0.5 to 0.55mm deep.
100 300 135/cm 2 2.3mm Blue’s logo stamp. THROUGH First pass alone looked good. Second pass went all the way through the rubber.

Cut

Power Speed Focus depth Shape Results
Full 150 auto Blue’s logo stamp Cutting out around engraved shape
Full 200 auto Address stamp Had to do two passes of this even though it was outlining an already engraved stamp.

Gasket Rubber

BUNA-N sheet gasket from Amazon.com/Small Parts, 1/16"

https://www.amazon.com/gp/product/B0075DXN4K/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

This stuff smells HORRIBLE when cut.

Cut

Power Speed Focus depth Shape Results
Full 250 auto 1-1/8 x 1-3/4 washer Almost penetrated, easy to remove by hand. Some flame.
Full 300 auto 1-1/8 x 1-3/4 washer Did not penetrate, hard to remove cut part, but could do it.

Resin

Smooth Cast 325 Polyurethane Resin

https://www.smooth-on.com/products/smooth-cast-325/

Engrave

Power Speed LPI Passes Focus depth Shape Depth Notes
25 400 225 3 auto circle - 11mm 1mm? engraved through about 1mm of resin and took a thin layer of wood on the 3rd pass.

Cut

Power Speed Focus depth Shape Results
Full 200 auto Address stamp ???.

Glow-in-the-dark Jewellery Stock

Cut

Power Speed Focus depth Shape Results
6 200 auto Pendants very good - smoother edges than 5/195.
5 195 auto Pendants Best yet, pretty easy to get the pieces out, and cut well.
5 200 auto Pendants cut alright - but was a bit of a struggle to get the pieces out due to the thickness of the glowing layer.
5 210 auto Pendants cut through the plastic, but the glowing layer was almost untouched… worked well - pieces didn't come out, but I could get them out easily

Apollo write on transparency

Remember to check if there is chlorine if you get new sheets! burn a little on the end of a copper wire under a torch, if you see green flames, don’t use it!

  • 200 speed, 5 power : cut through two sheets

  • 150 speed, 5 power : cut most of the way through three sheets, but they kind of fused together.

  • 150 speed, 10 power, paper in between sheets, cut through 4 sheets exactly

  • 150 speed, 20 power, paper in between sheets, cut through 5 sheets and marked the 6th

  • 150 speed, 30 power, paper in between sheets, cut through 6 sheets and marked the 7th

  • 150 speed, 40 power, paper in between sheets, cut through 7 sheets cleanly, and mostly cut the 8th

  • 150 speed, 70 power, paper in between sheets, cut through 12 sheets and marked the 13th

  • 150 speed, 80 power, paper in between sheets, cut through 15 sheets cleanly, and a couple more unevenly.