# Vibratory finishing

Selecting and qualifying vibratory mass finishing for burr removal, edge rounding and surface improvement without losing dimensions or retaining media.

Reviewed: 2026-11-01

Tags: processes, finishing, vibratory-finishing, deburring

A **2.040 mm** example part losing **0.012 mm** and **0.014 mm** from its two faces finishes at **2.014 mm**, only **0.001 mm** below the upper limit of **2.000 ±0.015 mm**. Verify starting-size and removal variation, uncertainty, burrs and edge radius.

Unbalanced motors move parts and media in a vessel. Wet processes add compound and water. Qualify the cycle for the actual equipment, including part separation. [Walther Trowal, mass-finishing technology](https://www.walther-trowal.com/en/mass-finishing-technology)

The process can address burrs, edges and surface texture across batches, but “vibratory finish” is not a numerical acceptance requirement. A successful route must achieve the intended surface while preserving size, functional edges, holes and cleanliness. Qualification should use representative parts with realistic incoming burrs and surface condition.

## Define the finishing objective

| Objective | What to specify and inspect |
| --- | --- |
| Deburring | Burr locations, allowable remaining burr and whether loose or folded material is acceptable |
| Edge rounding | Target edge break or radius, its limits and edges that must remain sharp |
| Smoothing | Texture parameter and measurement conditions, plus dimensional allowance |
| Polishing/burnishing | Appearance or reflectivity reference and relevant surface-integrity checks |
| Cleaning | Residue or particle requirement appropriate to the next operation |

These objectives can overlap, but passing one does not establish the others. Removing a protruding burr does not demonstrate a controlled radius; a shiny face does not show that an internal intersection is deburred. Walther Trowal's brochure, marked **06/17**, lists deburring, radiusing, smoothing, polishing and cleaning as distinct tasks and emphasizes the combination of machine, media, compound and water. [Walther Trowal brochure](https://www.walther-trowal.com/fileadmin/user_upload/Produkte/Datenblaetter/imagebroschuere_engl_01.pdf)

Identify the worst incoming burr and the smallest permitted finished feature before trial processing. If the time needed to remove that burr over-rounds another edge or exceeds the size allowance, change the upstream burr condition, tooling or finishing route rather than assuming more time will solve the conflict.

## Media and compound selection

Media material, abrasive grade, shape and size are separate selections. Walther Trowal's UK consumables page offers ceramic grades from cutting to non-abrasive polishing, and plastic media from cutting to non-abrasive polishing. It describes lower-density plastic media as gentler for softer metals, while also identifying **V2030** plastic media for smoothing titanium or cobalt-chromium before polishing. Therefore “plastic for soft parts, ceramic for hard parts” is an incomplete selection rule. [Walther Trowal UK consumables, undated](https://www.walthertrowal.co.uk/consumables)

CLM Vibetech's **21 October 2015** guidance links media selection to cutting action, cushioning, feature access and separation. It explains that the shape must reach relevant edges without becoming trapped, and that adequate media can reduce collision damage. Use those as trial variables; a nominal media size alone does not establish either complete coverage or protection from part-on-part damage. [CLM Vibetech, function of media](https://www.clmvibetech.com/about/whats-new/vibratory-finishing-machines/2015/10/function-media-vibratory-finishing-machines)

Compound is not merely an arbitrary addition to water. The Walther Trowal brochure describes cleaning, degreasing, corrosion protection and maintaining media cleanliness and cutting behavior. Its UK page gives **T77** corrosion protection and **KFL** degreasing as named examples. Select chemistry for the actual alloy, soils, media and downstream operation; temporary protection is not a permanent corrosion-performance claim. [Walther Trowal brochure](https://www.walther-trowal.com/fileadmin/user_upload/Produkte/Datenblaetter/imagebroschuere_engl_01.pdf), [UK compound examples](https://www.walthertrowal.co.uk/consumables)

## Geometry, lodging and dimensional limits

Review holes, slots, cross-holes, undercuts, pockets and threads against the actual media shape, including orientations in which it could wedge. Also examine whether two components can nest together. Walther Trowal supplies separating beads specifically for flat or thin parts that tend to adhere during processing; their availability does not eliminate the need to check the actual part family. [Walther Trowal special media](https://www.walther-trowal.com/en/mass-finishing-technology/consumables/consumables-special-media)

Media access is not assured simply because a feature admits a chip. A blind pocket may retain media or liquid, while an inaccessible internal edge may receive insufficient action. Inspect the required internal locations during trials and after separation. Include removal checks for lodged chips in the release process when the geometry warrants them.

Dimension loss must be measured where it matters. Raised edges, broad faces, narrow ribs and sheltered regions need not finish at identical rates. Specify protected features or consider fixturing where bulk contact is unsuitable. Rösler describes individual chambers for sensitive components and clamped processing for particular larger workpieces; those configurations are distinct from an unrestricted bulk batch. [Rösler rotary-vibrator configurations](https://www.rosler.com/en/products/mass-finishing/rotary-vibrator)

## Separation is part of the process

Rösler's *Rotary Vibrators* brochure **EN.145.22, revision 04/2023** describes internal screening in which media returns to the processing channel while finished parts leave over a screen. It also identifies continuous or periodic undersize-media discharge, liquid drainage and separated chambers as available process features. These are configuration-specific capabilities, not features guaranteed on every vibrator. [Rösler brochure, pages 6 and 23; revision on page 32](https://www.rosler.com/index.php?eID=downloadFile&f=161565&token=699af24935ca3c6fa20dfbb1a4e7b7175c234165)

Develop separation using the actual part and media population, not only new chips. Agree how media condition and undersize accumulation are controlled and how separated parts are checked. Include loading, unloading and transfer in the damage trial: successful finishing inside the vessel does not demonstrate that the final handling step preserves the surface.

## Cleaning and drying

Rinsing, removal of process liquid and drying require their own definition. Walther Trowal describes heated vibratory drying with granules and notes that drying media can also remove lightly adhering residue or produce a polishing effect. A drying step can therefore affect the final surface and introduce another media-removal requirement; it is not automatically equivalent to a specified cleanliness result. [Walther Trowal special-media guidance](https://www.walther-trowal.com/en/mass-finishing-technology/consumables/consumables-special-media)

Choose cleaning for subsequent bonding, plating, sealing or assembly requirements. Specify any restrictions on temporary corrosion inhibitor or compound residue, and protect cleaned parts from recontamination. Follow the selected compound's current SDS and equipment instructions for handling, guarding, noise control and liquid management rather than treating an aqueous process as unrestricted.

## Original dimensional-allowance example

Assume a flat component enters finishing at **2.040 mm** thickness and must finish at **2.000 ±0.015 mm**. A representative trial measures **0.012 mm** removal from one broad face and **0.014 mm** from the other:

`2.040 − 0.012 − 0.014 = 2.014 mm`.

With the same removal, a **2.050 mm** incoming part finishes at **2.024 mm**, above the **2.015 mm** limit. Verify edge radius, burrs and hole condition separately.

## Manufacturing handoff

Record alloy and condition, incoming burr locations, dimensions, required edge treatment, texture and appearance, and any protected surfaces. Identify the machine configuration, media product and condition, compound, loading arrangement, qualified cycle and separation/cleaning route. Inspect representative worst features during development, then agree production sampling and limits. Preserve a controlled reference sample where visual acceptance matters, with numerical requirements retained for functional dimensions and edges.

## Related reference

[Surface-finishing processes](index.md)