Laser Manual/Materials

Only approved materials should be cut with the Noisebridge laser cutter!

BANNED MATERIALS (NEVER USE THESE)

These materials must not be used in the laser cutter.

NOTE NEW ADDITION (2023-10): MDF is now banned.

Bad materials
Material	Notes
PVC	Contains chlorine. Will produce hydrogen chloride gas when used which is extremely toxic and also damages the laser optics.
Vinyl	Most contains chlorine. Will produce hydrogen chloride gas when used which is extremely toxic and also damages the laser optics.
PVC Foams	Most contains chlorine. Will produce hydrogen chloride gas when used which is extremely toxic and also damages the laser optics.
Foam Core	Usually made with PVC which is harmful as listed above.
Styrofoam	Can cause flash fires
Polycarbonate	Does not cut. TAP plastics sells both this and acrylic. Be sure to read your labels when purchasing material. Lexan is the trade name for Polycarbonate, while Plexiglass is the trade name for acrylic.
ABS or PETG	Gives off hydrogen cyanide which can kill you and also may damage the laser optics.
Fiberglass	Contains complex epoxies which will cause fires, chlorine, and cyanide. Also contains glass which will not cut.
Metals	Cannot be etched by this type of laser. Also is harmful as the reflective surface may cause the laser to be reflected back up to the head, damaging it. If someone claims to be etching metal using this type of laser then they are etching a metal with a plastic coating, anodized surface, or some other etchable surface on top.
MDF/fiberboard	Made of sawdust bound with glue, so it clogs filters so much that it's not excellent to other laser users. Use solid wood (or plywood, which uses much less glue) instead, or cut with the CNC or woodshop tools. Remember to follow proper dust-collection procedures when using those tools on MDF!

Known good materials

These materials are known to be ok for use with the laser cutter. The speed and power of the laser cutter will need to be set appropriately for the material and thickness in use. Below is a table showing the suggested settings when cutting or etching them.

Since upgrading the laser cutter to 150W, we have not tested and updated most settings. Please start at HALF the power as before and test carefully, increasing the power until you get a clean cut, and don't use power greater than 55% to prolong the life of our tube. (you probably won't be able to cut wood or MDF thicker than 1/4 inch or 6mm)

Old 100W Laser Cutter Settings for Known Good Materials

Material		Engraving			Cutting				Scoring		Date	For 150 W laser?	Remarks
		Speed mm/s	Power %	Test pics	Speed mm/s	Power %	Kerf mm	Test pics	Speed	Power
Acrylic	3/32" ≈ 2.4mm	400	5		50	55						unknown
	1/8" ≈ 3mm	400	5		30	55						unknown
	3/16" ≈ 4.8mm	400	5		20	55						unknown
	1/4" ≈ 6mm	400	3		12	55	0.1					unknown
Cardboard	3-4mm single corrugated				200	55			400	10		unknown
	6mm two layers corrugated				50	55			400	15		unknown
Cardstock (white, 100lb)					200	20			400	5		unknown	Higher speed reduces browning on edges.
Construction paper (3-sheet stack)	3-sheet stack				60	15						unknown	Higher speeds might work just as well. Make sure to clamp corners with magnets or weights. Compressor usually blows away scrap well, but watch carefully.
Fabric	Heat N Bond woven fusible				100	12						unknown
	KONA cotton from Fabric Outlet				100	7						unknown	Not a clean cut - you have to pull it apart, but cuts rip cleanly.
	Silky fabric from Fabric Outlet				100	7						unknown	lovely clean cut
		Engraving			Cutting				Scoring
Material	Material	Speedmm/s	Power %	Test pics	Speedmm/s	Power%	Kerfmm	Test pics	Speed	Power	Date	For 150 W laser	Remarks
Plywood	birch, 1/8" ≈ 3mm	500	5-25 varies by shade	200..800mm/s×5..55% + depths	25	50		15..50mm/s×10..50%50..100mm/s×50..100%				✓	50% 25mm/s gives reliable full cut
	birch, 1/4" ≈ 6mm	400	5-10 varies by shade		30	55						unknown
Rubber, natural	McMaster Carr #8525T53				20	55						unknown
Silicone	McMaster Carr #1460N24				10	55						unknown	Doesn't cut fully through - only enough to rip pieces by hand.
Sorbothane Rubber	1/8"				13	50						unknown	Creates inky black liquid; washes off easily with water.
	1/4" with adhesive backing				6	50						unknown	Adhesive side up

The Laser Gallery contains some past projects and cutting tests.

Sourcing Material

In general, Amazon and eBay are pretty good resources.

For plastics: Tap Plastics is nearby Noisebridge, but is expensive. The Tap Plastics offcut bin is a great resource and a great deal. eplastics online is another option, and Mr. Plastics is cheapest but is in San Leandro.

For woods: Discount Builder Supply is nearby.