An end-effector builder in Hamamatsu, Japan supplying robotics and automation has a pocketed 7075 aluminium tooling plate where the edges must be deburred but the dowel holes and flatness cannot move. SurfacePolish supplies finishing machines, media and compounds across borders and offers a free sample trial, in which the plate is shipped to Xiamen and returned with observed results and a proposed media, compound and cycle direction for the buyer to assess. This brief is written for a buyer in Hamamatsu working on robotics and automation; it describes equipment, media and a scoped sample review, not a local polishing service.
What is the size and mass spread inside one part family, and does one machine have to cover both a heavy casting and a small gripper jaw?
What is the smallest hole, slot, keyway or cross-drilling the charge must not enter or plug, and how will a lodged medium be detected and removed?
What does the finishing step actually have to deliver before the next operation, whether that is assembly, anodising, painting or a functional test, and who defines that requirement?
Two housings made to the same drawing can need different routes because of alloy and temper. A 6061-T6 machined body is soft enough to smear and peen under a heavy ceramic charge, and it marks where a steel charge has transferred iron. A 7075 part is stronger and cuts differently. Austenitic stainless work-hardens at the surface and responds to media pressure rather than to sharp cutting. Hardened 4140 or a nitrided seat may tolerate only a light edge break, because the finishing step cannot be allowed to remove the case. Castings can open porosity that machining had closed. Record the temper, the hardness range and the heat treatment, and establish whether an anodise, passivation or paint step follows, because that step usually sets the residue and smut limits the finishing cycle has to respect.
Long parts and heavy parts both fall outside a round bowl. A tub vibrator uses a rectangular chamber, so the working length extends along one axis while the bed stays shallow, which suits linear-axis beams, long manifolds and welded frames that cannot tumble end over end. The part is immersed or supported rather than turned, which removes bending risk from a divider, but energy per unit area is lower and a heavy burr takes longer. A grinding finishing machine works the other way, using higher removal energy to take off a defined layer or a heavy machining burr before refinement. That route cuts functional edges quickly and needs a tighter assessment of what may be removed. The deciding questions are part length, mass, how the part can be supported, and whether the critical face can be presented to the media at all.
| Machine route | Where it fits | What it will not do |
|---|---|---|
| Magnetic finishing machine | Fine deburring and light refinement of small precise features such as small bores, narrow slots and fine internal radii | Small working envelope that excludes housings and long parts, with pin media that can lodge in the fine features it reaches |
| Vibratory finishing machine, bowl type | General deburring and refinement of machined housings, plates and brackets that fit and can tumble without racking, with easy mid-cycle inspection | Continuous part-on-part contact and no access to deep internal passages; thin plates and finished mounting faces need separation |
| Disc finishing machine | Fast, high-energy edge breaking and surface refinement on small robust parts and uniform batches of gripper jaws, blocks and fittings | High impingement and edge-loss risk on thin, soft or aluminium parts, and the geometry must suit the disc working gap |
| Centrifugal barrel finishing machine | Small precise parts and short cycles with high contact pressure, such as spools, small inserts and compact machined components | Rounds edges and can distort thin unsupported sections quickly; results are sensitive to charge weight, speed and stop time |
Compound carries debris away, keeps the media from loading and buffers the chemistry against the metal. Alkaline and neutral families are common for general deburring and cleaning; acidic families may be chosen where a descale or brightening effect is wanted; silicate-bearing products can leave a tenacious film that is hard to remove from a bore or a sealing land. On aluminium an effective corrosion inhibitor usually matters, because the wrong chemistry darkens the surface during or after the cycle. Concentration, flow and temperature shift the result, so dosing should be metered rather than judged by eye, and rinse water hardness, chloride content and suspended solids all affect foaming and what remains behind. Where an anodise or paint step follows, the film and smut left by the cycle become the buyer's problem, so define how the surface will be checked.
| Media | Best fit | Watch out for |
|---|---|---|
| Heavy-cut ceramic, angle-cut triangles in a coarse size class | Removing a substantial milled or turned burr from open external edges and pockets on steel and stainless automation parts before a refinement stage | Cuts functional edges and corners aggressively, leaves a coarse surface on aluminium, and lodges in slots whose width approaches the media section |
| Magnetic finishing pins and fine magnetic media | Small precise items such as spools, orifice plates, small valve parts and fine slot arrays where tumbling media cannot reach the feature | Limited working envelope, pins lodge in the same fine features they are chosen to reach, and the surface signature differs from tumbling |
| Dry media such as walnut shell and corn cob | Drying assistance and light surface polish after a wet cycle, particularly on parts with pockets and threads that must not stay wet | Does not deburr or refine metal significantly, generates dust, and must not be treated as a cleanliness step |
| Steel media, including balls and shaped pins | Bright finishing and edge blending on stainless automation components where appearance and a burnished surface matter | Transfers iron to aluminium and carbon steel, needs a corrosion-inhibiting compound, and must be separated magnetically or by screen at unload |
Edge rounding beyond limit is the failure that most often turns a finished automation part into scrap, because the features that round first are the ones that set position. A bearing bore lip, a dowel hole edge, a seal groove corner or the edge of a ground mounting land can lose a fraction of its geometry under a high-energy charge and still look uniform and polished. Coarse or dense media, an over-long cycle and a heavy load ratio all accelerate it, and aluminium rounds faster than stainless under the same conditions. Because the damage is invisible to a casual look, checking has to be deliberate: measure the feature before and after with an optical comparator, a radius gauge or a moulded replica, and compare the result with the limit on the drawing. Masking, a shielding fixture or a gentler medium are the usual mitigations to test.
| Failure mode | Likely cause | How to catch it |
|---|---|---|
| Grey aluminium smear transferred onto stainless parts in a shared batch | Aluminium fines retained in media, compound or the machine sump after an aluminium lot, with no purge before the stainless lot | Check stainless surfaces under angled light for a dull grey film, review the changeover record, and inspect the charge and sump for retained fines |
| Burr remaining inside a cross-drilled intersection or an internal corner | Media too large to enter the intersection, part orientation that shields the feature, or a cycle stopped before that feature was reached | Borescope the intersection at a fixed angle, compare with a first-article reference, and use a pin or probe to feel for a lip on sampled parts |
| Bearing bore, bore lip or dowel hole edge rounded past the drawing limit | High-energy route, over-long cycle, dense or coarse media, or a functional edge run without masking or a shielding fixture | Measure the defined edge feature before and after with an optical comparator, radius gauge or moulded replica, and compare it with the maximum radius on the drawing |
| Threads rounded, galled or opened out by edge finishing | Media working the thread crest during a long or high-energy cycle, with no plugging or masking on the hole | Run go and no-go thread gauges on every sampled hole, inspect the crest at magnification, and confirm that plugs or masks were fitted and removed |
Hamamatsu City's own English-language industry profile describes a manufacturing city positioned between Tokyo and Osaka whose post-war base - textiles, musical instruments and motorcycles - developed into transport equipment, precision machinery, optics and electronics. It names Suzuki and Honda as rooted in the city, Yamaha and Kawai as instrument makers, and Hamamatsu Photonics as the anchor of an optoelectronics field that extends into medical devices and precision measurement instruments, and it states that transportation equipment is a key pillar while musical instruments are a signature strength. The city publishes industrial statistics by industry category and has adopted a second Hamamatsu industrial innovation plan, designating seven growth sectors supported through industry, academia, government and finance collaboration.
The nearest part of that base to this brief is aerospace: The same city profile records that Hamamatsu companies are investing in aerospace technologies alongside next-generation mobility, placing local aerospace work inside the mobility supply chain.
Optics and photonics hardware, precision measuring instruments and instrument-grade cosmetic parts put a premium on scratch-free surfaces, controlled edge break and cleanliness before coating or assembly. Musical instrument manufacturing adds cosmetic metal finishing, while automotive and aerospace work adds burr-sensitive machined features and sealing faces where edge condition affects function and inspection.
A Hamamatsu buyer's first question is whether the part is instrument-grade (where cosmetic surface quality and scratch-free edge condition dominate) or a functional precision part (where burr removal, edge break and roughness on a mating or sealing face dominate); that distinction decides the process and the media and compound combination to be trialled on samples.
Freight context: Tokyo-Osaka national corridor (city position as described by Hamamatsu City). The city's official profile states that Hamamatsu is strategically located between Tokyo and Osaka, so freight for machine deliveries and sample parts moves along that corridor; the city has no international seaport of its own, and no Hamamatsu port-authority or cargo-terminal page could be verified in this research, so seaport routing for this city remains unconfirmed.
Chinese industrial machinery entering Japan is classified under the Customs Tariff Law, whose harmonised schedule sets the classification and the General Rate; the Temporary Tariff Measures Law sets a Temporary Rate for certain products, and where the WTO rate or an EPA rate for the goods is lower, that lower rate is applied. The applied rate therefore depends on the exact commodity code, and on whether an economic partnership agreement covers the goods and their origin, so a landed-cost figure has to be confirmed against the specific machine before it is quoted. Japan Customs' monthly country table for August 2026 records exports to China of 1,809,133 million yen and imports from China of 2,361,239 million yen, the largest single-country line in the Asian table, with imports from China up 22.5 per cent year on year.
The customs authority is Japan Customs, the Customs and Tariff Bureau of the Ministry of Finance, with regional customs at Tokyo, Yokohama, Nagoya, Osaka and Kobe. Any person importing goods must declare them to the Director-General of Customs and obtain an import permit after examination and payment of customs duty and consumption tax. The declaration is normally filed by the importer or by a customs broker acting as proxy, on a triplicate import (customs duty payment) declaration form (Customs form C-5020) supported by the invoice, the bill of lading or air waybill, a certificate of origin where a WTO rate applies, certificates of origin for preferential rates, packing lists and freight and insurance documents where required, plus any licence or certificate demanded by laws other than the Customs Law. More than 90 per cent of import procedures are computerised. A JIS Mark certificate is a separate, voluntary third-party scheme; foreign exporters are eligible to apply, and certification bodies must comply with ISO/IEC 17065.
SurfacePolish supplies from Xiamen, China. The buyer's own destination rules, conformity marking, tariff classification and documentation responsibilities stay with the buyer; confirm them against the authorities named above before ordering.
Ask for a record that says what was actually done, rather than one that asserts a result. A useful batch record lists the part numbers and quantities in the lot, the machine used, the media type and size class, the charge mass and its age since the last screen or top-up, the compound product and dose, the rinse water source, the cycle time and any interruption, plus the inspection results and the lot disposition. Request the media and compound data sheets offered by the supplier. Where aluminium and stainless run in the same shop, ask for the changeover note covering media purge, machine cleaning and compound replacement. This is process documentation from a finishing operation, not a certificate of compliance with any standard, and it supports the buyer's own traceability.
A sample trial answers a narrow question: what happened to these parts under these settings on this equipment. It does not prove that a production lot will be uniform, because load ratio, media age and operator practice all shift the outcome, and it does not transfer a result from a coupon to a complex housing. It cannot establish a particle count, a cleanliness level or fitness for any regulated application, and it does not show whether a machine or medium is approved or qualified for a buyer's process. It cannot establish a cycle time, a cost per part, a capacity or a delivery schedule, and it says nothing about how the surrounding handling or automation should be arranged. Treat the returned parts and the settings record as evidence for the buyer's own engineering and quality decision, and plan the production route with its own first-article and sampling discipline.
A bore cannot be protected by the cycle alone; it is protected by what is decided before the cycle. Masking or plugging the bore, keeping the part out of contact with heavy neighbours, choosing a lighter route and shortening the cycle all reduce the load the bore sees, but none of them guarantees a dimension. That is why the bore must be measured before and after at the same points, with a bore gauge or CMM, and compared with the drawing limit. SurfacePolish does not promise a tolerance or a result; the trial reports what was observed on the parts tested, and the dimensional acceptance decision stays with your own metrology and quality functions.
SurfacePolish does not coat, anodise or paint parts, and no finishing cycle here should be treated as a coating preparation specification. A coating or anodising step usually makes residue, smut and embedded debris more visible rather than less, and a compound film left in a bore becomes your problem at the next operation. Define what your own coating process requires and how you will verify it, then ask for the parts to be checked against that requirement. A trial can report what was observed on the tested surfaces and the settings used, but the fitness of a surface for a downstream coating step is your own process decision.
Cycle time depends on the starting burr, the alloy and temper, the media size class, the compound and how much edge refinement is wanted, so no figure can be quoted in advance. A part that needs only a light edge break runs very differently from one that must shed a milled burr or a recast layer before refinement, and a two-stage route has to count both stages. The useful approach is to test one or two defined stop points on representative parts and record what changed at each. SurfacePolish does not promise cycle times or capacity; treat any timing on returned parts as an observation from that run rather than a production commitment.
Use Hamamatsu, Japan as the destination on the enquiry and state whether the deliverable is equipment, media and compound, a representative sample review or a line concept. A destination does not imply local stock, a local service point or a local delivery time.
Japanese buyers work to JIS (Japanese Industrial Standards), enacted and revised under the Industrial Standardization Act after the law was renamed from the Industrial Standardization Act (工業標準化法) to the Industrial Standardization Act (産業標準化法) in 2019; JIS content is administered through the Japanese Industrial Standards Committee (JISC). Drawings normally reference JIS or customer specifications for surface finish, and ISO 9001 management-system certification is commonly requested as general industry practice.
Sources were retrieved on 2026-09-29 and describe the local industrial and trade context only. They do not evidence any SurfacePolish project, shipment, installation or service in Hamamatsu.
The buyer wants the pocket edges and the plate faces deburred without warping the plate or rounding the dowel holes that locate the tooling.
Send the material, dimensions, approximate weight, batch quantity, the incoming condition and photographs of the difficult features. Mark which features must not be contacted by media and state how the result will be inspected. This form carries source reference PSEO-0900; quote it if you prefer an additional manual reference.
Open the SurfacePolish enquiry form Email a prepared enquiry
No price, lead time, certification or result is promised here. Confirm whether a sample trial is available for the specific part and what the trial can and cannot show.
Page PSEO-0900 · revised 2026-09-29 · cross-border equipment, media and scoped sample review. City context is sourced and cited above.
Email : info@surface-polish.com
IPv6 network supported 
+86-592-2381506 