A CNC shop quotes ₹85 per accepted shaft. It machines 100 pieces, but only 95 pass inspection. What does the job actually earn? This worked example uses customer-supplied blanks and excludes GST.

Calculate the cost per accepted piece

For the batch, setup and first-piece approval cost ₹1,200, machine time including the operator ₹4,000, tooling ₹900, outside processing ₹1,100, and inspection and packing ₹400. Total measured job cost is ₹7,600. The five rejected pieces have no recovery value in this illustration.

Divide ₹7,600 by 95 accepted pieces: ₹80 each. At ₹85 each, the customer invoice is ₹8,075. That leaves ₹475 after the listed job costs, before any overhead excluded from those rates. Dividing by all 100 pieces gives ₹76 and hides the cost of rejection.

Record the numbers against one job

Link the quotation, drawing revision, customer material challan, work order, job cards and inspection result. Separate setup from machine running time. Record the accepted, rejected and reworked quantities and reconcile unused blanks. Include outside processing and tool consumption. If the machine-hour rate includes labour, avoid charging it again. Add the extra cost of rework once and count the repaired unit once after acceptance.

Decide whether to repeat the quotation

At the same ₹7,600 cost, 90 accepted pieces cover the measured cost. At 89 pieces the job is ₹35 short. Recalculate when additional tooling or rework changes the cost. Compare quoted and actual costs on repeat orders of the same drawing revision. Check whether a variance arose from a one-off setup delay, repeated tool wear or rejected output before changing the quotation.

Bring a recent job card and quotation to a CNC job-costing demo with Thirvu Soft in Coimbatore. We can walk through the figures needed for a quoted-versus-actual report.