Overview

A shim etching manufacturer is judged on one number more than any other: the thickness that actually arrives in the box. Shims set clearance in a stack, so a 0.05 mm shim that measures 0.056 mm throws off the assembly torque, preload or bearing gap it was meant to correct. Plants that etch in-house gauge every incoming coil, control the etch so thickness loss stays inside a known window, and sort the finished lot into thickness bands before packing — a step a trading company cannot perform because it never touches the sheet.

Production is organised around stack-ups rather than single part numbers. One order often contains several shim layers, each with its own outline, pocket and tab, and each layer has to sit flat against the next. Etching is well suited to that because every layer is cut from the same gauge in the same bath, pockets are half-etched to a controlled depth, and no stamping burr stands the stack off by a few microns.

Parameter Window

• Available Materials: stainless steel 304/316L, brass H62, copper, spring steel 301, nickel, aluminum 5052
• Material Thickness Range: 0.02–1.5 mm
• Tolerance: ±0.02 mm on delivered thickness band, ±0.05 mm on outline, 0.05 mm flatness per 100 mm
• Minimum Feature: 0.1 mm slot and 0.15 mm hole on 0.05 mm stock; half-etched pocket depth ±10% of target
• Surface Options: passivation, degrease and oil-free finish, tarnish inhibitor, adhesive-free stacking, laser-marked identification
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. Stack-Up Review — Read the assembly drawing as a stack, check that the sum of the shim layers lands on the target clearance, and flag any layer whose tolerance consumes the whole budget.
2. Gauge Selection & Verification — Pick the coil by nominal thickness and measure it at several points; the mill gauge, not the drawing, sets the starting point for every downstream number.
3. Cleaning & Lamination — Degrease and laminate resist on both faces so outlines, tabs and pockets are defined on each side independently.
4. Exposure — Expose outline and pocket artwork in one pass with shared fiducials, keeping the pocket concentric to the outline within ±0.05 mm.
5. Development — Open the resist over cut lines and pocket areas, then inspect for pinholes that would etch a stray dimple into a sealing face.
6. Controlled Etching — Etch through for the outline and to depth for pockets, with bath strength and dwell logged so thickness loss per lot is known rather than assumed.
7. Thickness Grading — Measure each sheet or strip on a micrometer plan, sort into 0.005 mm bands, and label the band on the pack so assembly can pick without re-measuring.
8. Flatness Check & Packing — Verify flatness on a surface plate, stack without adhesive, interleave, and ship with the gauge and grading record.

Core Advantages

1. Thickness you can build a stack around: Incoming gauge is verified and finished lots are graded into 0.005 mm bands, so the drawing tolerance is supported by measurement rather than by hope.
2. No tooling amortisation: Every new shim outline is a new film, which keeps prototype stacks, service parts and low-volume variants affordable.
3. Burr-free faces: Chemical cutting leaves no roll-over, so layers sit flush and a sealing or sliding face is not scratched by a stamped edge.
4. Pockets in the same operation: Half-etched relief, oil grooves and clearance pockets are formed without a second setup or a machined step.
5. Direct engineering dialogue: Stack-up questions go to the process engineer who sets the etch parameters, and a marginal design is reworked before the film is plotted.
6. No trading markup: As a shim etching manufacturer we quote from the plant's own cost base, and annual blanket orders carry the volume breaks the line can actually support.

Typical Applications

• Bearing and gearbox shims: Preload and end-play adjustment layers from 0.05 mm to 0.5 mm in spring steel and stainless.
• Motor and pump spacing: Lamination stacks and rotor clearance shims with half-etched relief for adhesive flow.
• Optical and sensor spacing: Thin brass or aluminum spacers that set focal distance to a few microns.
• Hydraulic valve shims: Orifice and spring seat shims where edge quality affects leakage across the land.
• Electronics assembly: Thermal and grounding shims in copper, supplied oil-free for bonding.
• Fixture and tooling shims: Setup shims cut to the machine outline, often ordered in mixed thickness sets.

Design Notes & Process Considerations

1. Thickness tolerance, not just nominal: State the acceptable band, for example 0.05 ±0.005 mm, and say whether thickness is measured before or after passivation.
2. Etch loss allowance: Expect 0.003–0.008 mm of thickness loss on thin stock; if the shim is thickness-critical, specify the target as finished thickness.
3. Stack identification: Mark each layer with its thickness and position, either etched or laser marked, so a mixed set cannot be assembled in the wrong order.
4. Pocket depth control: Half-etched pockets should be called out as depth from the original surface, with a tolerance of ±10%, and kept away from sealing lands.
5. Tab and handling: Add a 2–3 mm tab or a carrier frame on shims below 0.05 mm; unsupported thin parts curl at the edge during packing.
6. Flatness after grading: Ask for 0.05 mm per 100 mm flatness and specify that parts are packed flat, since a shim that bows will not seat even if the thickness is right.