Half of the blast cabinet and blast room questions we get are really media questions in disguise: how fast will it strip, what profile will it leave, how many times can I recycle it, and will my recovery system handle it. This blast media chart is Kresco’s engineering reference for the 22 abrasives most shops run, and it answers most of those questions in one table. Below the chart is a short guide to reading it, because the column that matters most changes with the job.
Blast media comparison chart
| Media | Mesh | Shape | Mohs | Density (lb/ft³) | Recycle cycles | Working speed | Typical PSI | Cost | Typical applications |
|---|---|---|---|---|---|---|---|---|---|
| Steel shot | 8–200 | Round | 8 | 280 | 200+ | Medium | 20–90 | $$ | Cleaning, finishing, peening |
| Steel grit | 10–325 | Angular | 8 | 230 | 200+ | High | 20–120 | $$ | Removing heavy scale |
| Cast zinc/aluminum shot | 12–60 | Round | 3 | 246 | 200+ | High | 30–90 | $$ | Cleaning, deburring, deflashing, paint removal |
| Stainless steel shot | 8–170 | Round | 8 | 300 | 200+ | High | 20–90 | $$ | Cleaning, finishing |
| Stainless steel grit | 8–170 | Angular | 8 | 270 | 200+ | High | 20–90 | $$ | Cleaning, finishing, etching |
| Cut wire shot | 8–60 | Round | 4–5 | 150 | 200+ | High | 30–90 | $$ | Cleaning, finishing, peening |
| Alumina zirconia | 20–240 | Angular | 8 | 150 | 200+ | High | 30–90 | $$$ | Cleaning, deburring, polishing hard metals |
| Ceramic beads | 8–46 | Round | 7 | 150 | 100+ | Medium | 20–90 | $$$ | Cleaning, finishing, peening |
| Corn starch | 16–60 | Angular | 2 | 45 | 14–17 | Med–high | 20–45 | $$ | Composite and sensitive-substrate coating removal, deflashing, etching |
| Wheat starch | 12–80 | Angular | 2 | 45 | 12–15 | Medium | 20–45 | $$ | Composite and sensitive-substrate coating removal, deflashing, etching |
| Glass beads | 30–440 | Round | 5.5 | 100 | 8–10 | Medium | 20–55 | $$ | Cleaning, finishing |
| Plastic media | 12–100 | Round or angular | 3–4 | 45–60 | 8–10 | Med–high | 20–60 | $$ | Cleaning, paint removal |
| Aluminum oxide | 12–325 | Angular | 8.5–9 | 125 | 6–10 | High | 20–90 | $$$ | Cleaning, finishing, deburring, etching |
| Corn cob | 8–40 | Angular | 3–4.5 | 20–25 | 4–5 | Med–low | 30–60 | $ | Cleaning, paint removal, polishing |
| Silicon carbide | 12–325 | Angular | 9 | 95 | 3–4 | Very high | 20–90 | $$ | Cleaning, finishing, etching |
| Garnet | 30–220 | Angular | 7 | 145 | 2–4 | Medium | 20–90 | $$ | Cleaning, finishing, deburring |
| Walnut shell | 6–100 | Angular | 3.5 | 40 | 1–3 | Low | 30–60 | $$ | Cleaning, paint removal, polishing |
| Crushed glass | 30–400 | Angular | 5.5 | 100 | 1–2 | High | 20–100 | $ | Cleaning, finishing, etching |
| Green diamond | 8–60 | Angular | 7 | 85–105 | 1–2 | Med–high | 30–120 | $ | Cleaning, finishing, etching |
| Star-Blast | 60–90 | Angular | 6.5–7 | 145 | 1–2 | Medium | 20–120 | $$ | Cleaning |
| Baking soda | 60–170 | Angular | 2.5 | 60 | 1 | Med–low | 30–60 | $$$ | Cleaning, paint removal |
| Coal slag | Various | Angular | 6–7 | 75–100 | 1 | Med–high | 40–120 | $ | Outdoor blast cleaning |
Source: Kresco media reference. Values are typical ranges; actual results depend on nozzle, pressure, standoff and substrate.
How to read the chart
Shape decides the finish
Round media (shot, beads) peens the surface: it closes it, leaves a satin finish, and is what you use for cleaning without cutting, and for shot peening where compressive stress is the goal. Angular media (grit, oxide, garnet) cuts: it leaves the anchor profile that paint, powder and thermal spray need to stick. If your spec calls out a profile in mils, you are in the angular rows.
Recycle cycles decide the economics
This is the column that separates a production setup from a disposable one. Steel shot and grit survive 200+ cycles, which is why every mechanical recovery floor in a steel-fab blast room runs steel. Aluminum oxide and glass bead give you 6 to 10, enough that a cabinet with a cyclonic reclaimer pays for itself. Coal slag, crushed glass and soda are one-and-done; they belong in outdoor or portable blasting where you are not trying to recover anything. Media that only recycles once or twice is a sign you should not be building a recovery system around it.
Density decides the recovery system
Pneumatic (vacuum) recovery moves media by air. It handles everything up to about garnet and aluminum oxide comfortably, but heavy steel grit and large shot, at 230 to 300 lb/ft³, overwhelm it. That is the rule behind our standing advice: light media and moderate volume, go PARS2000 pneumatic; steel media, go MARS2000 mechanical. Density also tells you how much a hopper of media weighs and what your bucket elevator is lifting.
Mohs hardness decides what you can blast
Media harder than the part will cut it; media softer will clean it. Steel (Mohs 8) on a steel weldment is a cutting job. Plastic media (3–4) or starch (2) on aluminum aircraft skin or a composite panel strips the coating and leaves the substrate alone, which is why aerospace MRO runs plastic and starch in cabinets built for them. Walnut and corn cob (3–4.5) clean soft metals and molds without changing dimensions.
Working speed vs. cost
Silicon carbide is the fastest-cutting media on the chart and recycles only 3 to 4 times; aluminum oxide is nearly as fast and lasts twice as long, which is why it is the default in industrial cabinets. Crushed glass and green diamond are cheap and fast but single-use. There is no universally cheapest media, only the cheapest cost per part once you multiply price by cycles and divide by speed.
Quick picks by job
- Steel fab, structural, trailers, heavy equipment going to paint: steel grit in a blast room with mechanical recovery.
- Production cabinet, mixed steel parts, deburr and prep: aluminum oxide with a cyclonic reclaimer.
- Stainless, food, pharma, or anywhere iron contamination is a problem: stainless shot or grit, glass bead, or aluminum oxide; never carbon steel media.
- Aluminum, composites, aircraft skins, molds: plastic media, starch, walnut or corn cob.
- Cosmetic satin finish on aluminum, stainless or castings: glass bead, or wet blasting with fine bead.
- Shot peening to spec: steel, stainless or cut wire shot, or ceramic beads, in a peening system with Almen control.
- Outdoor or portable blasting, nothing recovered: coal slag, crushed glass, or garnet.
Media, then machine
We ask about media before we size anything, because it decides the recovery system, the separator setting, the dust collector load and the nozzle. Tell us your part material, the finish or profile you need, and how many hours a week you blast, and we will match the media and the equipment together. Request a quote or a free process evaluation, or start with the Abrasive Blast Rooms Buyer’s Guide.
Blasted metal is bare metal. Whatever media you choose, protect the surface between blasting and coating with Cortec VpCI rust prevention.
