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What to Send With a Copper Machining RFQ

September 21, 2026

A copper RFQ that arrives with a model and the word “copper” gets a cautious price, or a price that changes later. The list below is what a shop needs to commit to a number, in the order it matters.

The files

A 3D model. STEP is the safe default. IGES works. Native CAD formats often do not open cleanly at the other end.

A 2D drawing as PDF. This is where everything that is not geometry lives: tolerances, finish, edge condition, plating, notes. On simple flat parts a DXF or DWG is useful as well, because it can drive the profile directly.

If you only have one, send the drawing rather than the model. The model can be rebuilt from a good drawing. The intent cannot be recovered from a model.

The material line

State one of the following, never neither.

The grade, for example C110 ETP, C145 tellurium copper, C101 OFE.

The requirement, for example “minimum 90 percent IACS, grade open” or “ultra high vacuum service, oxygen free required”. This version is often cheaper, because it lets the shop propose a grade that cuts faster.

If temper matters, say so. Annealed, half hard and hard copper behave differently when bent and machined.

Quantity, honestly

Give the real quantity and say whether it repeats.

Setup and programming are paid once per order, so they dominate small quantities and disappear at larger ones. A shop that knows you will reorder quarterly will treat the fixturing investment differently from a shop that thinks this is a one-off.

Asking for prices at two or three quantity breaks is normal and useful. Inflating the quantity to get a better price is not, because the price you accepted assumed an order you are not going to place.

Tolerances that mean something

Mark the two or three dimensions that actually mate, locate or seal. Give everything else a sensible general block tolerance.

A drawing with a tight general block and no exceptions costs more and communicates less than one with a loose block and three specific callouts. Realistic bands are in copper machining tolerances.

Edge condition as a number

“Break all sharp edges 0.2 to 0.4 mm” is a cost a shop can estimate. “Burr free” is an open ended hand-finishing instruction, and it is the single largest source of scatter between quotes for the same copper part.

If only some edges matter, name them. See deburring copper parts.

Surface finish, per face

Put an Ra value on the faces that need one and name what each face does: electrical contact, thermal interface, sealing, plated, cosmetic. Leave the rest as machined.

Plating and coating

If the part is plated, state the finish, any underlayer, the thickness for contact and non-contact areas, the plated and masked areas, the standard you work to and whether dimensions are before or after plating. That is six lines and it prevents most of the arguments that happen after first article. Details in copper busbar plating.

Inspection and documentation

Say what you need before the shop quotes, not after it ships:

  • First article inspection report, and to which standard
  • Dimensional report on every piece, on a sample, or none
  • Material certificate
  • Certificate of conformance
  • Plating test report

Each of these is real work. None of them is expensive if it is quoted. All of them are expensive if they arrive as a surprise requirement.

Delivery and logistics

  • The date you need parts, and whether it is hard
  • Incoterm and destination
  • Packaging requirement, especially whether the part must arrive untarnished
  • Whether partial shipments are acceptable

Copper tarnishes. If your incoming inspection rejects brown parts, agree the packaging now.

The commercial notes

  • Quote validity, because the metal price moves. See how the copper price lands inside your quote.
  • Whether an NDA is required before files are shared
  • Your target price, if you have one
  • Whether tooling and fixturing are paid separately

A copy and paste RFQ header

Part:            [name and number]
Files:           [STEP + PDF drawing]
Material:        [grade, or requirement with grade open]
Temper:          [if relevant]
Quantity:        [real quantity] + [repeat schedule]
Tolerances:      [general block] with [named critical dims]
Edge condition:  break all edges [x] to [y] mm
Finish:          [Ra and face] / as machined elsewhere
Plating:         [finish, thickness, area, before or after]
Inspection:      [FAI / cert / report]
Needed by:       [date]
Ship to:         [country, incoterm]
Notes:           [NDA, packaging, target price]

Send that and the quotes you receive will be comparable, which is the whole point.

If you would rather send it once instead of five times, that is what this site does. One RFQ reaches up to 3 shops that already cut copper, you get their quotes directly and you place the order yourself. Reply within 24 business hours.

Frequently asked questions

Is a STEP file enough on its own?

For a rough budget, sometimes. For a real quote, no. A model carries geometry but not tolerance, finish, plating, edge condition or material. Those are what actually set the price on a copper part.

Should I tell shops my target price?

It helps more than it hurts. A shop that knows your target can tell you which requirement is blocking it, or decline early instead of wasting both sides' time.

What if I do not know the copper grade?

Write the requirement instead. State the conductivity, current, thermal or vacuum need and mark the grade as open. A shop can then offer the cheapest alloy that meets it.

Need a quote for this part?

Send the drawing. We match you with up to 3 copper shops and reply within 24 business hours.

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