How to find the right Copper Shims & Shim Stock AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Copper Shims & Shim Stock
- Alloy
- C11000 ETP copper for thermal and electrical shims, and the listing must state it Many "copper" shims are actually brass, which conducts heat and electricity far less well.
- Thickness and tolerance
- Buy to a stated nominal thickness with a stated plus/minus tolerance, and verify with a micrometer A shim's whole job is a precise gap, so an unspecified tolerance defeats the purpose.
- Temper
- Annealed (soft) for gasket-style sealing and conforming to surfaces, half-hard or hard for spacing shims that must not creep under load Soft copper crushes to seal but will relax under sustained clamp load.
- Flatness and surface
- Rolled flat, burr-free edges, and clean or protected surfaces for thermal-interface use Burrs and dents create air gaps that ruin thermal contact and throw off spacing.
- Form factor
- Roll or sheet stock for cutting your own, pre-cut squares for repeat sizes, laminated (peelable) shim for adjustable stacks Cutting thin stock cleanly is hard, so the right format saves scrap and time.
- Standard
- Sheet and strip should reference ASTM B152 or an equivalent mill specification It ties the material to controlled chemistry and conductivity rather than a seller's claim.
Brands that matter
- Precision Brand: Long-established US maker of shim stock in brass, steel and other metals, with a thickness-labelled range.
- Artus: Shim specialist offering precision and laminated shims to custom sizes.
- Revere Copper Products: US mill source of copper sheet and strip that shim stock is cut from.
- Aurubis: Copper strip producer, including oxygen-free grades.
What to avoid
- Listings that give thickness only in one unit with no tolerance
- "Copper-colored" or plated shims with no alloy stated
- Thin copper used as a structural spacer under heavy permanent clamping, because annealed copper creeps
- Pre-cut CPU/GPU thermal shims of unknown thickness, because wrong thickness leaves an air gap or overstresses the die
Questions
Does soft or hard copper shim stock work better for a heat-transfer gap?
Use soft annealed copper when it must conform to uneven surfaces, and harder temper when it must hold an exact thickness. In both cases, use thermal compound on both faces.