Why Two Machine Shops Quote the Same Part Twice as Much

Send the same STEP file to five shops and you will get five numbers, sometimes twice apart. Buyers read this as dishonesty or inefficiency. Usually it is neither. Each shop priced a different process, because each shop saw a different way to make the part. Understanding where the gap comes from tells you which quote is genuinely cheap and which one is quietly cutting corners.

The Route Through the Machine Is a Choice

A simple bracket can be made in two setups or five. It can start from a sawed block, from a milled blank, or from a pre-machined casting. The CAM engineer decides, and the decision depends on the shop's equipment. A 3-axis shop adds op-splits and hand flipping; a 5-axis shop finishes critical faces in one chucking. Two routes, two cycle times, two prices. The cheaper route is not always the better part: hand-flipped setups introduce datum error on geometric features.

Fixturing Quietly Prices the Part

How the part holds still is the second big variable. A production fixture with soft jaws and locator pins costs money to build but holds every part the same. A cheap vice on a tricky part costs less upfront but burns time finding the datum and produces drift. On small batches the vice wins; on production the fixture pays back. A quote that ignores fixturing is betting that the part is easy, and it becomes expensive the moment it is not.

Tolerance Is Interpreted, Not Measured

One shop reads a ±0.05 mm callout as standard precision. Another reads the same number as a precision feature and programs an extra finish pass, a CMM check and a temperature-controlled room. Both are making the drawing, but they are priced differently. The expensive shop is not wrong: on a mating bore, the extra pass is what makes the reorder assemble. On a non-critical face it is waste. The question is whether the tolerance matters where it was called.

Certifications and Quality Systems Have a Cost

An ISO 9001 shop, an AS9100D shop and an untitled job shop have different overhead. The certified shop pays for calibration, records, internal audits and traceability. That cost shows up in the rate, but it also shows up in the paperwork. A buyer who needs certificates and CMM reports is not comparing the same service as a buyer who just wants a bracket milled.

The Low-Bid Trap

The quote that comes in 40 percent below the others is usually one of four things: the shop misunderstood the quantity, the shop plans to skip inspection, the shop has never machined the material before, or the quote is a loss-leader that rises on the reorder. Ask how the part will be fixtured and which features will be CMM-checked. A shop that cannot answer the process question in writing is already telling you where the money went.

What We Do at KGL

When KGL quotes a part, the process route is part of the answer: which operations, which machine, how it is held, which features are inspected. Buyers can see why the number is what it is, and they can trade process against price deliberately, not by guessing. The goal is a quote that matches the real work, not the lowest guess.

Conclusion

Price comparison only works when the process is on the table. The next time the quotes differ that much, stop comparing dollars and ask each shop for the route. The gap will shrink, and the true cost will finally be visible.

FAQ

Q: Is the cheapest quote always cutting corners?

A: No, but it always means something. It may mean the shop is running near capacity and wants the order, or it may mean a skipped operation. The fix is to ask for the process route and the inspection plan in writing before choosing.

Q: Why does the same shop quote me differently on the reorder?

A: Setup and first article are one-time charges. The reorder repeats only material and machine time. If the reorder price jumps instead, the shop likely added a revision, a material change or inspection you did not authorize.

Q: Should I always pick the middle quote?

A: No. Pick the quote whose process you understand and whose inspection plan matches the part's critical features. A well-explained $100 part beats an unexplained $60 part that fails on assembly.