laser cutter: move over materials list (#22)

Author: DanNixon

src/SUMMARY.md

@@ -10,6 +10,7 @@
 - [Equipment](./equipment/README.md)
     - [Abridged List](./equipment/abridged_list.md)
     - [Laser Cutter](./equipment/laser_cutter/README.md)
+        - [Materials](./equipment/laser_cutter/materials.md)
     - [Bambu Lab P1S](./equipment/bambulab_p1s/README.md)
         - [User Guide](./equipment/bambulab_p1s/user_guide.md)
     - [Prusa MK3](./equipment/prusa_mk3/README.md)

src/equipment/laser_cutter/README.md

@@ -14,3 +14,5 @@ It cuts stuff using a laser.
 ## Usage notes
 
 > **It is not permitted under any circumstances to leave this machine running unattended!**
+
+A list of compatible materials can be found [here](./materials.md).

src/equipment/laser_cutter/materials.md

@@ -0,0 +1,62 @@
+# Laser suitable materials
+
+Materials that can be cut/engraved (largely taken from the [London Hack Space wiki](https://wiki.london.hackspace.org.uk/view/Silvertail_A0_Laser_Cutter#Allowed)).
+
+If you want to cut a material which is not on the allowed list you must contact the maintainers through the members email list to ask permission.
+
+## Prohibited materials
+
+- **Anything that cannot, with reasonable confidence, be identified**
+- Cork (fire risk)
+- Wood which isn't explicitly laser-grade (laser contamination, fire risk, emissions)
+- Food (laser contamination, fire risk, emissions)
+- Body parts
+- Plastics containing PVC (laser contamination, emissions)
+- Plastics containing ABS (laser contamination, fire risk, cyanide emission)
+- Fibreglass (laser contamination, fire risk, emissions)
+- Circuit boards (laser contamination, fire risk, emissions)
+- Polycarbonate (laser contamination, fire risk)
+- All metal (except engraving anodized aluminium)
+- Polystyrene (laser contamination, fire risk, emissions)
+- Polypropylene (laser contamination, fire risk, emissions)
+- HDPE (high-density polyethylene or polyethylene) (laser contamination, fire risk, emissions)
+- Carbon fibre (laser contamination, fire risk, emissions)
+- Shuttering ply (laser contamination, fire risk, emissions)
+- Latex (laser contamination, fire risk, emissions)
+- Leather, all. (laser contamination)
+- **Anything not explicitly allowed (either in the lists below, or by prior permission)**
+
+## Allowed
+
+Woods:
+
+- Laser-grade MDF (max 8mm)
+- Laser-grade plywood
+    - Birch ply (max 9mm)
+    - Poplar ply (max 9mm)
+- Balsa wood
+- Paper (cutting only)
+- Card/Cardboard (cutting only)
+ 
+Plastics:
+
+- Thin Polypropylene sheet (<1mm)
+- Acrylic (max 10mm)
+- Foamcore (non-PVC variety)
+- Correx (Genuine non PVC)
+- Depron foam (Fire risk, must be closely monitored)
+- EVA Foam (if real)
+- Delrin (max 8mm)
+ 
+Textiles:
+
+- Cloth/felt/hemp/cotton (Not plastic-impregnated fabric)
+- Polar Fleece
+ 
+### Engraving only
+
+- Stone
+- Ceramic tile
+- Non-resinous wood IE hardwood
+- Glass
+- Anodised Aluminium