Brass Shim Washers – Precision Shim Rings | Manufacturer & Exporter from India
We are one of the leading manufacturers, suppliers and exporters of Brass Shim Washers and Brass precision shim rings from India. We have been supplying Brass Shim Washers to the world market for 3 decades. Brass Shim Washers — also known as Brass shim rings, Brass spacer washers, Brass tolerance washers, Brass feeler washers, or Brass adjustment washers — are thin, flat, annular precision components used to fill gaps, adjust clearances, take up tolerances, or provide precise axial spacing in mechanical assemblies. Unlike standard plain washers (which provide a bearing surface for a fastener), shim washers are precision-ground or precision-turned to extremely tight thickness tolerances, making them an essential tool for fine adjustment in bearing housings, gearboxes, pump assemblies, valve bodies, optical instruments, and precision machine tools. Brass is the preferred material for shim washers in many applications because it combines good mechanical properties with excellent machinability, low magnetic permeability, corrosion resistance, and compatibility with both metric and imperial assembly systems. Our Brass Shim Washers are manufactured to DIN 988, IS 2016, ANSI B18.22, and custom specifications, with thickness tolerances as tight as ±0.01 mm. ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 certified, we supply individual shim washer orders to large OEM production quantities with consistent quality.
Overview
In precision engineering, very few components contribute as much to assembly accuracy as shim washers. A shim washer is placed between mating surfaces to precisely control axial clearance, bearing preload, gear mesh centre distance, valve stem clearance, or component alignment. The ability to select from a range of thicknesses — sometimes as fine as 0.05 mm increments — allows engineers to achieve sub-millimetre dimensional control in production assemblies without resorting to expensive custom machining of every individual component.
Brass Shim Washers are particularly valued in applications where: (1) non-magnetic material is required — Brass has negligible magnetic permeability, making it essential in sensitive instrumentation and magnetic shielding applications; (2) corrosion resistance is needed without stainless steel’s risk of galling; (3) good thermal and electrical conductivity is beneficial; (4) the shim must be soft enough not to damage precision bearing or housing surfaces; and (5) the appearance of a bright, golden shim is important for aesthetic assemblies.
Common application contexts for Brass Shim Washers include: bearing housing axial preload adjustment in motors, pumps, and gearboxes; gear centre distance fine-tuning in precision drive trains; valve clearance setting in engine cylinder heads; optical instrument focus adjustment; measuring tool and gauge calibration; PCB standoff spacing; and spacer rings in cylindrical assemblies such as hydraulic actuators and pneumatic cylinders.
| Standard | Grade | Composition | Hardness | Remarks |
|---|---|---|---|---|
| India IS 319 / IS 291 | Free-Cutting Brass | Cu 57–59%, Pb 2.5–3.5%, Zn Bal. | 55–70 HRB | Standard machining grade |
| Europe EN 12164 | CW614N (CuZn39Pb3) | Cu 59%, Pb 3%, Zn Bal. | 60–75 HRB | Standard CNC bar grade |
| Europe (Low-Lead) | CW508L (CuZn37) / CW505L (CuZn35) | Cu 63–65%, Zn Bal., Pb <0.1% | 65–80 HRB | RoHS-compliant, no lead |
| USA ASTM B36 | C26000 (Cartridge Brass) | Cu 68–72%, Zn Bal. | 50–60 HRB | Best formability, used for stamped shims |
| USA ASTM B16 | C36000 (Free-Cutting) | Cu 60–63%, Pb 2.5–3.7%, Zn Bal. | 55–70 HRB | Machined shim rings from bar |
| UK BS 2870 | CZ106 / CZ108 | Cu 68–72%, Zn Bal. | 50–60 HRB | Brass strip/sheet for stamped shims |
| Germany DIN 17660 | CuZn37 / CuZn39Pb3 | Cu 61–65%, Zn Bal. / with Pb | 55–80 HRB | Strip (CuZn37) or bar (CuZn39Pb3) |
| Japan JIS H 3100 | C2600 (equivalent to C26000) | Cu 68–72%, Zn Bal. | 50–60 HRB | Japanese JIS brass strip |
| China GB/T 4423 | H65 / H68 | Cu 64–68% / 67–70%, Zn Bal. | 55–65 HRB | Chinese standard Brass strip |
Manufacturing Process
Brass Shim Washers are manufactured by two routes depending on size and quantity: precision CNC turning from Brass bar (for small-to-medium batches and large inner diameters) or precision blanking/stamping from Brass strip (for thin shims and high-volume production). CNC-turned shim rings are produced on CNC turning lathes with precision facing and parting operations, achieving thickness tolerances of ±0.01–0.05 mm. The inner bore and outer diameter are machined to ISO tolerance classes as specified. For stamped shims, precision-ground Brass strip is progressively blanked in compound dies to produce ID and OD simultaneously, with strip thickness already controlled at material stage to ±0.01 mm. After blanking, shims are deburred in vibratory finishing systems, cleaned, inspected, and optionally tumble-polished for appearance. Thickness is verified on every batch using calibrated digital micrometers.
| Inner Dia. (d1 mm) | Outer Dia. (d2 mm) | Available Thickness Range (mm) | Thickness Tolerance |
|---|---|---|---|
| 3 | 6 | 0.1, 0.2, 0.3, 0.5, 1.0 | ±0.04 mm |
| 4 | 7 | 0.1, 0.2, 0.3, 0.5, 1.0 | ±0.04 mm |
| 5 | 8 | 0.1, 0.2, 0.3, 0.5, 1.0 | ±0.04 mm |
| 6 | 10 | 0.1, 0.2, 0.3, 0.5, 1.0 | ±0.04 mm |
| 8 | 12 | 0.1, 0.2, 0.3, 0.5, 1.0 | ±0.04 mm |
| 10 | 16 | 0.1, 0.2, 0.3, 0.5, 1.0, 2.0 | ±0.05 mm |
| 12 | 18 | 0.1, 0.2, 0.3, 0.5, 1.0, 2.0 | ±0.05 mm |
| 15 | 22 | 0.1, 0.2, 0.3, 0.5, 1.0, 2.0 | ±0.05 mm |
| 20 | 28 | 0.2, 0.3, 0.5, 1.0, 2.0, 3.0 | ±0.05 mm |
| 25 | 35 | 0.2, 0.3, 0.5, 1.0, 2.0, 3.0 | ±0.05 mm |
| 30 | 42 | 0.3, 0.5, 1.0, 2.0, 3.0 | ±0.08 mm |
| 40 | 55 | 0.3, 0.5, 1.0, 2.0, 3.0 | ±0.08 mm |
| 50 | 68 | 0.5, 1.0, 2.0, 3.0, 5.0 | ±0.10 mm |
International Standards
Brass Shim Washers are manufactured per DIN 988 (Shim Rings for Roller Bearings), IS 2016 (Plain Washers), ISO 7089 / ISO 7090 (for general purpose), ANSI B18.22.1 (Plain Washers, inch series), and custom specifications. Dimensional tolerances follow ISO 286 (ISO tolerances and fits) and DIN 7168 (general tolerance for machined parts). For bearing preload applications, the h class tolerance for thickness per DIN 988 is maintained.
Tolerances and Performance
Our Brass Shim Washers are manufactured to thickness tolerances of ±0.01 mm for precision-turned types (CNC machined) and ±0.04–0.10 mm for stamped types, depending on size. Inner diameter tolerance: H7 (clearance fit with shaft) as standard; H6, H8, or JS6 available on request. Outer diameter tolerance: h9 as standard. Flatness: max 0.01 mm per 10 mm diameter. Parallelism (face-to-face): max 0.01 mm per 10 mm diameter for precision CNC-turned shims. All shims are 100% thickness-measured using digital micrometers with 0.001 mm resolution.
Industries Served
Brass Shim Washers find application in precision engineering and machine tools, bearing housing and gearbox assembly, hydraulic and pneumatic actuators, automotive engine valve clearance setting, pump manufacturing, optical instruments and cameras, measuring instruments and gauges, aerospace sub-assemblies, medical devices, electrical equipment spacing, and marine machinery.
Turnaround Time
Standard DIN 988 sizes in common Brass grades are available from stock for rapid dispatch. Custom sizes, precision-tolerance variants, or large volume orders have a lead time of 4–6 weeks. We offer prototype shim sets (assorted thickness packs) for development and trial applications.
Why Choose Us
With three decades of precision manufacturing experience, we have the capability to produce Brass Shim Washers to tighter tolerances than most catalogue fastener suppliers. Our CNC precision-turning capability achieves ±0.01 mm thickness on individual shims — a level of accuracy that stamped commodity shims cannot match. We can supply full assortment kits (multiple thicknesses in a single packaged set), custom ID/OD combinations not listed in standard catalogues, and non-standard materials (Stainless Steel, Aluminium, Phosphor Bronze) alongside Brass. Custom packaging with customer part numbers and labels is readily available. Our ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 certified quality system ensures dimensional traceability and consistency across all production batches.
Customer Testimonials
“We require Brass shim washers to very tight thickness tolerances for bearing adjustment in precision spindle assemblies. Cable Glands India consistently delivers within our ±0.015 mm specification with full dimensional reports. No other supplier has matched their precision at this price level.”
— Robert Williams, Engineering Manager, United Kingdom
“We trialled several Indian suppliers for Brass shim washers before settling on Cable Glands India. Their CMM reports are detailed and honest — they highlight any borderline dimensions rather than just approving everything. That level of integrity is rare and very much appreciated.”
— Marc Dubois, Quality Engineer, France
Frequently Asked Questions (Q&A)
Q1: What is the difference between a shim washer and a plain washer?
A plain washer (DIN 125/ISO 7089) is used as a bearing surface under a bolt or nut head and is made to relatively loose dimensional tolerances. A shim washer (DIN 988) is manufactured to precision thickness tolerances (as tight as ±0.01 mm) for use as a precise spacer or gap-filler in engineering assemblies. The key differentiator is thickness precision.
Q2: What is the thinnest Brass shim washer you can manufacture?
We can manufacture Brass Shim Washers down to 0.05 mm thickness in small diameters (up to approximately d2 = 20 mm) using precision Brass strip and compound blanking dies. For thinner requirements, Brass shim stock cut to shape from precision-rolled strip is available.
Q3: Do you supply shim assortment kits?
Yes. We can supply Brass Shim Washer assortment kits in a range of thicknesses (e.g. 0.05, 0.1, 0.2, 0.3, 0.5, 1.0 mm) for a given ID/OD combination, packaged in a labelled compartment box. These are popular for maintenance and field service applications where the exact shim thickness needed is unknown until assembly.
Q4: What is DIN 988?
DIN 988 is a German standard specifying shim rings for use with rolling element bearings — defining the ID, OD, and thickness tolerances for precision shims used in bearing preload adjustment and housing bore compensation. Our Brass Shim Washers conform to the dimensional requirements of DIN 988 where applicable.
Q5: Can you supply shims with a split (slotted) profile for easy assembly?
Yes. Split (horse-shoe or C-shaped) Brass shim washers are available for applications where the shim must be inserted radially into a partially assembled joint without disassembling the shaft or bolt. Please specify the slot width required when ordering.
Q6: What is the hardness of Brass shim washers?
Standard Brass (CW614N / C36000) shim washers have a hardness of approximately 60–80 HRB (Rockwell B scale), which is softer than Stainless Steel or hardened steel shims. This makes Brass shims preferable where the bearing surfaces must not be scratched or where some degree of conformance to surface irregularities is acceptable.
Q7: Do Brass shim washers corrode in outdoor or marine environments?
Standard Brass has good atmospheric corrosion resistance but can suffer dezincification in aggressive salt-water environments over time. For marine or outdoor applications where long-term dimensional stability is critical, dezincification-resistant (DR) Brass or Stainless Steel shims are recommended.
Q8: Can Brass shim washers be used in high-temperature applications?
Brass retains its properties up to approximately 150°C. Above 150°C, the material softens and creep under load may cause loss of shim thickness over time. For temperatures above 150°C, Stainless Steel or Inconel shims are recommended.
Q9: Do you offer custom ID/OD combinations not in your standard range?
Yes. Any ID/OD combination from approximately ID 2 mm to ID 200 mm can be manufactured in Brass. Unusual ratios (e.g. very thin annular ring, or very wide flange) are also achievable. Please provide your drawing or dimensions for quotation.
Q10: What surface finish do Brass shim washers have?
Standard CNC-turned Brass shim washers have a machined surface finish of Ra 1.6–3.2 µm on the flat faces. Precision ground variants (Ra 0.4–0.8 µm) are available on request for ultra-precise bearing applications. Stamped Brass shims from strip have the natural strip surface finish.
Q11: Can shim washers be used in electrical applications?
Yes. Brass shim washers are used in switchgear assemblies, transformer terminals, and busbar connections as precision spacing elements. Their good electrical conductivity means they can also serve as a conductive path where required.
Q12: What is the minimum order quantity?
For standard sizes, our MOQ is 500 pieces per thickness/size combination. For custom sizes, MOQ starts from 1,000 pieces. Smaller sample quantities are available for development purposes at a sample charge.
Q13: Do you supply Stainless Steel or Phosphor Bronze shim washers?
Yes. We manufacture shim washers in Stainless Steel (SS304, SS316), Phosphor Bronze (CuSn6, CuSn8), Aluminium, and Copper in addition to Brass. Contact us with your material and dimensional requirements.
Q14: What packaging do you use for shim washers?
Brass Shim Washers are packed in polythene bags by thickness and size, with labelled inner packaging and outer cartons. Custom retail packaging, assortment kits in blister packs or compartment boxes, and private-label packaging are available on request.
Q15: Do you supply shim washers with measurement reports?
Yes. A dimensional inspection report covering all critical dimensions (ID, OD, thickness on minimum 5 pieces per batch) is available as standard. Full CMM reports and 100% inspection are available for precision and high-reliability applications at additional cost.
Glossary of Terms
DIN 988 – German standard for precision shim rings for rolling bearings; defines ID, OD, and thickness tolerances. Bearing preload – A controlled axial force applied to a rolling element bearing to eliminate internal clearance and improve rigidity and precision; shim washers are used to set preload accurately. H7/h6 fit – ISO tolerance system notation for fits; H7 is a standard clearance bore tolerance used for bearing inner ring installation. Blanking/stamping – A metal forming process where a punch and die are used to cut a flat shape from sheet or strip material. Flatness – A geometric tolerance specifying how closely a surface approximates a true flat plane; critical for shim washers to function as accurate spacers. Parallelism – A geometric tolerance specifying how parallel two surfaces are to each other; critical for shim washers used in precision gap-filling applications.
Related Parts
Brass plain washers, Brass spring washers, Brass machined washers, Brass lock washers, Brass tab washers, Brass wave washers, Stainless Steel shim washers, Phosphor Bronze shim rings, Brass hex nuts, Brass bolts, Brass studs, Brass spacers, Brass standoffs, Brass distance pieces, Brass tolerance rings
Request a Quote Today
For precision Brass Shim Washers in standard or custom specifications, contact our technical sales team. We welcome enquiries for development quantities through to large OEM production batches. Email: sales@cableglandsindia.com | Phone: +91-22-43449300. ISO 9001:2015 | ISO 14001:2015 | ISO 45001:2018 certified precision manufacturer and exporter of Brass Shim Washers from India.