Student Material 001: Abrasive Media Quick Reference Guide¶

Material ID: U10M1-MAT-001 Purpose: Quick reference for abrasive media selection, specifications, and blasting parameters

Abrasive Media Comparison Chart¶

Media Type	Mohs Hardness	Shape	Mesh Sizes	Profile Depth	Reuse Cycles	Cost/lb	Best For
Aluminum Oxide	9.0	Angular	24–220	1.5–4.0 mils	5–10	$0.80–1.50	Metal profiling, aggressive cleaning
Silicon Carbide	9.5	Angular	16–240	2.0–5.0 mils	3–5	$1.50–3.00	Hardened steel, carbide tooling
Garnet	7.5–8.0	Sub-angular	30–120	1.5–3.5 mils	3–5	$0.25–0.60	General metal prep, waterjet cutting
Glass Bead	5.5	Spherical	40–325	0.3–1.5 mils	20–30	$0.40–0.80	Peening, satin finish, cleaning
Steel Shot	8.0	Spherical	S-70 to S-780	1.0–3.0 mils	100–200	$0.40–0.70	Shot peening, heavy descaling
Steel Grit	8.0	Angular	G-10 to G-200	2.0–5.0 mils	50–100	$0.45–0.75	Aggressive profiling, shipyard
Walnut Shell	3.0	Angular	6/10–40/60	0.1–0.5 mils	3–5	$0.60–1.00	Delicate cleaning, mold stripping
Corn Cob	2.5	Angular	10/14–40/60	0.1–0.3 mils	1–3	$0.40–0.70	Dry stripping, log cabin cleaning
Baking Soda	2.5	Crystalline	60–270	None (dissolves)	0 (single use)	$0.50–0.80	Graffiti removal, food equipment
Plastic Media	3.0–4.0	Angular	12–80	0.1–0.5 mils	5–10	$2.00–5.00	Aerospace paint stripping

Application	Recommended Media	Pressure (PSI)	Nozzle Size	Standoff Distance	Angle
Rust removal (steel)	Aluminum oxide 60–80	70–90	3/8"	6–8"	45°
Paint stripping (metal)	Garnet 60–80	60–80	5/16"	8–10"	45°
Glass frosting	Aluminum oxide 120–180	40–50	1/4"	10–12"	90°
3D print cleanup (FDM)	Glass bead 100–170	30–50	1/4"	8–10"	45°
Brass/bronze cleaning	Walnut shell 12/20	30–50	5/16"	8–10"	45°
Weld cleaning	Aluminum oxide 36–60	60–80	3/8"	4–6"	45°
Wood texturing	Glass bead 70–100	20–40	1/4"	12–14"	45°

Standard	Name	Cleanliness	Typical Use
SP 1	Solvent Cleaning	Remove oil, grease, soil	Pre-treatment for all methods
SP 5	White Metal Blast	100% clean	Immersion service, high-performance coatings
SP 10	Near-White Blast	95% clean	Most industrial coatings
SP 6	Commercial Blast	67% clean	Standard coating prep (makerspace default)
SP 7	Brush-Off Blast	Remove loose material	Maintenance painting

Mesh Size	Diameter (mm)	Diameter (inches)	Diameter (μm)
16	1.19	0.047	1190
24	0.71	0.028	710
36	0.50	0.020	500
60	0.25	0.010	250
80	0.18	0.007	180
120	0.13	0.005	125
180	0.08	0.003	84
220	0.06	0.0025	63

NEVER use silica sand — causes silicosis (irreversible lung disease)
Minimum PPE: Safety glasses (Z87.1), N95 respirator, hearing protection, gloves
Test unknown coatings for lead before blasting (LeadCheck swab)
Dust collector must be running before, during, and 5 minutes after blasting
Maximum exposure time: 2 hours continuous, then 30-minute break

Last Updated: 2026-03-19