How to quote a machined part, line by line

The part on the bench for this one is a spool valve, SV-3120, revision C. A turned and ground steel body, a honed bore with a tenth-of-a-thou class tolerance, 2 outside finishes, 1,200,000 pieces a year on a 6 year program.

The buyer sent a print, a step file, a cost breakdown workbook and a volume release schedule. Every figure below is the one this part actually carries on the worked example that runs through this site, so you can check the arithmetic end to end and none of it is hypothetical filler.

The discipline that matters before any line gets priced is deciding what the part is made of, in the manufacturing sense.

A quote is a stack of small commitments, and each commitment needs to be traceable to something, a bar price, a cycle, a rate, a supplier’s number. The moment a line reads “misc” you have stopped estimating and started hoping.

Material, off the bar

The body comes out of 1215 cold drawn bar, 0.625 diameter, 2.555 gross length per piece once you include the cutoff and facing allowance.

Gross length is the honest number, since the saw kerf and the facing stock are real steel you paid for, and quoting on net length is the first of the quiet ways a quote goes light.

Bar price times gross weight per piece, divided through by yield, lands material at $0.240 a piece. Note the remnant too, the last unusable length of every bar, because at 1,200,000 pieces a year the remnants are tonnage, and whether they return credit as scrap steel belongs in the same line.

On a part that will sell around $1.41, material is 17 percent of the sell, which is worth noticing.

Every line needs a source.

On high volume turned work the material line is often the largest single commitment on the sheet, and it moves with a market you do not control. Date the bar quote that sits behind it, because a material line without a date is an opinion.

The routing, operation by operation

The routing is where estimating either respects the floor or ignores it. This part runs 4 inside operations before anything leaves the building.

OP-10 is the rotary transfer, turn, drill, cross-drill, groove and part off in one pass, 4.6 seconds of cycle, priced at $0.160 a piece. OP-20 is deburr and ultrasonic wash at 1.8 seconds and $0.028. OP-30 is a centerless grind on the 0.6245/0.6240 lands, 3.2 seconds and $0.078.

OP-40 hones the bore to 0.3125 +0.0004/-0.0000, 5.1 seconds and $0.135, and it is the most expensive inside operation on the part despite being fourth in line, because tight bores are paid for in seconds and in scrap risk.

Each of those prices is cycle time against the rate of the specific work center that will run it, and the rate has to be the burdened one, machine ownership, floor space, maintenance, operator and overhead share, the full build we walk through in what a burdened rate actually includes. Setup time rides on top, amortised across the release quantity.

At 1,200,000 pieces a year with releases around 50,000, setup pennies spread thin, which is exactly why the same part at 5,000 pieces would carry visibly different line prices. Volume is not a discount, it is a different denominator.

Setup, releases and the denominator

Every price above quietly divides by a quantity, and the quantity deserves as much scrutiny as the cycle. The release schedule in this package calls for roughly 50,000 pieces at a time against the 1,200,000 a year.

Volume is a denominator.

A changeover on the rotary is measured in hours, and those hours belong to the release that triggered them, so at 50,000 pieces a release the setup time adds fractions of a cent to each piece and disappears into the line price.

The identical changeover against a 2,000 piece trial order is a visible per-piece cost, which is why the same part at 2 volumes is 2 different quotes, and why copying last year’s price into this year’s volume is wrong in whichever direction hurts more.

The denominator discipline extends past setup. First article inspection and the PPAP effort amortise across the program. The bar quote behind the material line assumes mill quantities that only make sense at volume.

When a buyer asks for a price break table, most of what moves between the rows is not efficiency, it is denominators, and an estimator who knows which lines are quantity-sensitive can build that table in minutes instead of rebuilding the quote 4 times.

Outside processing, priced twice

Two operations leave the building, a carbonitride case and a zinc nickel plate. Outside processing is the part of the quote you do not control, so it gets priced twice.

First provisionally, from the last numbers those processes carried on similar work, $0.128 and $0.105 in this case, so the quote can keep moving while suppliers respond. Then firm, when Meridian comes back at $0.110 on the carbonitride and Calumet at $0.090 on the plate, and the provisional lines get replaced rather than averaged.

Two disciplines matter here. Carry the freight and the handling in the line, because a per-piece process price that ignores 2 truck moves is understated. And check whether the buyer requires source approval on the processors, since an unapproved plater discovered after award is a schedule problem you priced nothing for.

Price the lot, not the piece.

Lead time belongs in this section too, even though it never appears as money. The carbonitride and the plate each add days of transit and queue at the supplier, and the promise date on the quote has to survive both.

A quote that wins on price and then misses its first delivery because nobody counted the second truck move has converted a commercial win into an expediting bill, so the outside lines get a date check as well as a price check before the sheet moves on.

Tooling, amortised in the open

The tooling and gauging package for this part is $185,000. The buyer’s own workbook carries a tooling tab, ownership sits with the customer per their form, and the package amortises over year one volume, 1,200,000 pieces, which is $0.154 a piece.

The estimating failure with tooling is rarely the total. It is burying the total inside the piece price without saying so, which makes the quote look expensive against a competitor who listed tooling separately, or cheap against one who forgot it entirely.

Put the number where the buyer can see it, on its own line, amortised exactly the way their form asks.

QA, scrap and the last 2 cents

Final inspection, cleanliness spec and the PPAP burden amortise to $0.019 a piece here. It is the smallest line on the sheet and the easiest to wave through, which is why it deserves a moment of suspicion.

A cleanliness spec with a particle count, or a capability requirement on the honed bore, can multiply the line. Read the quality documents in the package before accepting the small number.

History beats the handbook.

Scrap and yield do not get their own line on this sheet, they live inside the cycle prices, and that is a defensible choice as long as it is a choice.

A honed tenth-class bore does not run at perfect yield in its first weeks. Whichever convention your floor uses, use it consistently, because a routing priced half with yield inside and half without is unauditable.

From unit cost to sell

Stack the lines. Material $0.240, the 4 inside operations $0.401 between them, outside processing $0.200 firm, QA $0.019, tooling $0.154. Unit cost lands at $1.014. Margin policy on this program is 28 percent, sell is $1.410, which is $1.69M a year at volume and $10.2M across the 6 year program.

Those 2 large figures belong on the quote summary, because the buyer is not buying a piece, they are buying a program, and the person who signs your quote should see what they are signing in program terms.

The number behind the number

One more check separates a quote from a guess. This part’s closest relative in the job history, a spool valve from the same family, was quoted at $1.28 and actually ran at $1.37.

Nine cents light, across 3.4 million pieces, is $306,000 that never came back. The build above is priced from what that job cost, which is the entire point of keeping history.

The print tells you what the part is. Only your own closed jobs tell you what it costs on your floor, and a line-by-line build that ends with a comparison against a real relative is the strongest quote a manufacturer can send.

If you are weighing tools to run this build faster, hold them to the same line-by-line standard, the whole comparison is in the buyer’s guide.