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Copper Busbar Machining
A busbar is mostly metal with a little machining on it, which is why the quote is decided by cross section, hole tolerances, bends and plating rather than by cycle time. The shops we match are the ones that handle those four things without drama.
Send the drawing. We read it, pass it to up to three shops whose work fits, and you deal with them directly. There is no commission on the order.
What the part needs
- Grade
- C11000 ETP for almost all busbar. C10100 only for vacuum or hydrogen brazed assemblies.
- Temper
- H02 half hard for stiffness, O61 annealed where the bar is formed.
- Hole tolerance
- Clearance holes ±0.2 mm or looser. Locating holes tighter, and there are usually only two.
- Bends
- Inside radius one to two times thickness. One radius across the bar so one tool covers it.
- Edges
- Break all edges 0.3 to 0.5 mm, written as a dimension.
- Plating
- Tin for indoor distribution, nickel for heat and welded joints, silver over nickel for switching contacts. Contact pads only, rest masked.
Grades that fit
Published typical values for the alloy, never a promise from a shop. Each grade has its own reference page.
- C11000
Electrolytic tough pitch copperThe default. Around 100 percent IACS, widely stocked in plate and bar, cheaper than C101 and machines the same way. - C10100
Oxygen free electronic copperOnly when the bar is brazed in hydrogen or lives in ultra high vacuum. The conductivity gain over C110 is about one point.
What drives the price
If a quote looks high, one of these is usually the reason, and most of them can be changed on the drawing.
- Metal weightCopper is bought by weight at a moving price. Every millimetre of thickness beyond the current rating is paid for on every bar, forever.
- Hole tolerancesTolerancing all holes like locating holes adds inspection time to every piece.
- BendsOne bend can cost more than the whole hole pattern on a small order.
- Plating areaFull length plating on a long bar is a cost paid on every piece for a benefit only needed at the ends.
What to put on the drawing
Send these and the quotes you receive will be comparable. The RFQ builder writes the material lines for you.
- Cross section justified against the standard your assembly is certified to
- Grade, temper and substitution note
- Clearance and locating holes separated by tolerance, all holes chamfered
- One bend radius, enough flat length at the ends
- Edge break as a dimension
- Plating type, thickness, plated and masked areas, dimensions before or after plating
- Real quantity and whether it repeats
Send the drawing
Short version here, or the full RFQ form with tolerance, finish and plating fields. Your files go only to the shops we match. Ask for an NDA and nothing moves until it is signed.
We are a matching service, not a machine shop. How matching works.
Questions buyers ask
Something else? Email .
What thickness and width should the busbar be?
That is set by current, temperature rise, ambient, plating and ventilation against the standard your assembly is built to. A wide thin bar cools better than a narrow thick one of the same area. Design against the standard, not a rule of thumb, and we match the drawing you send.
Can the shop bend the bar as well as machine it?
Most shops that run busbar do both. Say the temper you need and give one bend radius, and the shop plans the sequence so joint faces are machined after forming.
Is plating done by the same shop?
Almost always outsourced to a plater, with the machine shop managing it. Say who owns the result when the finish is wrong. Our screening asks every shop exactly that.
How many shops receive my busbar drawing?
Up to three, and only shops whose machines and copper experience fit. Shops see a preview with no name, company or files until they take the lead.