What to Confirm When You Supply the Material
Customer supplied material changes who owns the risk. Specification, condition, allowance and delivery all have to be agreed before anything is cut.
Supplying material is a reasonable choice. It is also a change in who carries the risk, so it needs to be agreed before cutting rather than after a sheet has been consumed.
Start by asking
Say in the request that you intend to supply the material. Whether a shop can work from customer material is confirmed per job, along with how it is handled once it arrives, so an order that assumes it will be accepted can lose a week.
What the fabricator needs to know
- The specification, written out: material type, grade, thickness and any standard it has to meet. "Mild steel" covers a wide range.
- The form it arrives in: sheet, plate, tube, profile, and the size of each piece.
- The condition: new, previously cut, sheared, weathered, or reclaimed. A recycled plate with a curved edge changes how parts nest and how much is usable.
- Certificates, if the project requires traceability. Say so at the quote stage, because it affects handling rather than just paperwork.
- Whether a cut edge, mill finish or protective film needs preserving.
Allowance, and the number that matters
A part nests on a sheet. The quantity of material needed is not the sum of the part areas, and cutting a set of parts from a sheet you supplied means that sheet is used up. Confirm the allowance for nesting and for the first article, and confirm who carries a shortfall.
In practice: buy enough material for the parts plus a margin, and agree what happens if a piece is scrapped during the run.
Delivery and handling
State when the material arrives, where it is unloaded, and who accepts it. A sheet delivered without a reference to the purchase order becomes unallocated stock in a shop that does not hold stock.
What stays with you
Ownership of the material and any remainder. Say whether offcuts return, are scrapped, or are kept. Say whether material is to be marked so it can be tracked through the shop.
Why this comes before cutting
Once a cut is made, a material problem becomes a fabrication problem. Thickness that is under nominal, a sheet with a bend in it, or a grade that will not form as expected all surface after cutting, and at that point the remedy is a new sheet rather than a conversation.
The reverse order works better: confirm the specification and supply the certificate before the work starts, and the same material question is answered while it is still cheap.
How to identify critical dimensions in a quote request covers the drawing side of the same request.