A productive RFQ is a controlled input package, not just a request for a price. The intended machine route depends on the part, manufacturing stage, datum, incoming error, handling, acceptance method and responsibilities after delivery. Missing data can create a comparison that looks simple but does not describe the actual application—and the gap is usually discovered at acceptance, when it is expensive for everyone.
This checklist does not state a price, delivery, capability or service scope for any specific project. It defines the information required for an application and commercial review, so that the quotation you receive answers the question you actually have. Used from the buyer side, it is also a filter: a supplier who does not ask for most of these items is quoting a machine, not a solution.
*Engineering concept illustration. It is not a quotation, confirmed configuration or customer installation.*
Part and Process Definition
Include the controlled drawing and revision, material specification, heat-treatment, coating and machining stage, sectional geometry, length, mass where relevant, functional surfaces, permitted contact areas and existing datums. Supply representative error maps or inspection records rather than only a statement that parts are bent: the shape of the incoming error decides the correction method, and two parts with the same “straightness problem” can need entirely different machine architectures.
| RFQ input | Purpose |
|---|---|
| Drawings and revision history | Defines the controlled part and change risk |
| Material/process stage | Frames recovery, surface and correction-window questions |
| Datum/features | Defines fixture, measurement and handling assumptions |
| Incoming variation | Identifies sample and trial requirements |
| Quality characteristic | Separates straightness, runout, bow, surface and end requirements |
| Volume and mix | Frames cycle, changeover and handling review |
| Current process | Reveals constraints, rework and measurement boundaries |
Three of these rows carry most of the project risk in practice. Revision history, because a machine scoped to revision B may be structurally wrong for revision D. Incoming variation, because a quotation validated on your best samples does not cover your worst production day. And the current-process row, because the existing rework loop, gauge limitations and handling constraints are often the real reason a new machine is being sought—stating them lets the supplier solve the actual problem instead of the nominal one.
Write the quality characteristic in drawing language, not shorthand. “Straight within 0.1” is three different specifications depending on whether it means centerline straightness over the full length, bow over a defined span, or runout to end-axis datums—and the difference decides fixturing, measurement and machine architecture. If the characteristic is still under engineering definition at RFQ time, mark it as open with an owner and a date, so the quotation can carry the assumption visibly instead of silently.
Handling, Measurement and Acceptance
Describe loading and unloading, orientation, floor space, utilities, upstream and downstream interfaces and any special material protection. Attach the customer inspection method, gauge status, support and span, calculation rule and pass/fail decision. An in-line result may need correlation to a released customer measurement—flag it now, not after the machine is built.
*Engineering concept illustration. Final method and configuration require part-specific engineering and trial evidence.*
Use the machine gauge versus customer gauge correlation guide to identify correlation needs, and the straightening sample test and acceptance guide to prepare representative trials. Where long or non-round parts are involved, the full-length profile straightness scanning page explains why scan-level evidence may be needed in the acceptance definition.
Define Scope and Commercial Assumptions
State the requested scope: machine, tooling, fixtures, measurement, loading, guarding, controls and data, documentation, training, spare parts, installation support, acceptance and any interfaces. Identify buyer and supplier responsibilities, local safety and compliance requirements, site readiness, requested schedule assumptions and the change-control process. Do not infer inclusion from a generic machine description—the phrase “straightening machine” has covered everything from a bare frame to a turnkey cell with gauging and robotics, and quotations that look comparable across suppliers rarely are until the scope lines are matched item by item.
*Engineering concept illustration. Measurement layout and acceptance must be defined for the actual workpiece.*
What Missing Data Costs Later
Each gap in the package does not disappear; it converts into an assumption that someone pays for at a later stage:
| Missing input | Where it surfaces | Typical consequence |
|---|---|---|
| Incoming error map | Application review | Wrong correction architecture proposed; rework at trial |
| Acceptance method and gauge | FAT / SAT | Machine accepted on one gauge, rejected on another |
| Datum definition | Fixturing | Fixture redesign; schedule slip |
| Handling and interfaces | Installation | Integration work discovered on site |
| Volume and mix reality | Production | Changeover or cycle mismatch vs. planning assumptions |
| Scope boundaries | Contract | Commercial dispute over what was included |
The pattern to notice: none of these failures are machine failures. They are information failures, and they are cheap to prevent at the RFQ stage relative to every later stage they can land in.
Preparing Samples and Error Maps That Carry Weight
Representative samples are the single highest-value item in the package, and their value depends entirely on how they are selected and documented. Send a spread, not a showcase: typical production parts, known-difficult parts, and parts at the edge of the incoming variation you intend the machine to handle. Label each with lot and process-stage identity, and include the inspection record taken before shipment—unsupported samples transfer the measurement problem to the supplier instead of the application question.
An error map does not need to be sophisticated to be useful. What the application review needs is the character of the error, not a research dataset: where along the length the deviation concentrates, whether it is single-plane or multi-plane, how it varies part to part and lot to lot, and what the current process does to it before the part reaches the straightening station. A sketch plus five measured parts with recorded positions answers those questions; a stack of pass/fail printouts does not. For the measurement discipline behind that record, the measuring datum selection guide covers the datum decisions that make the numbers comparable.
State also what cannot be supplied. If worst-case parts are genuinely unavailable—because the process is new, or the defect is intermittent—say so and define how that uncertainty will be handled: an expanded trial at FAT, a conditional acceptance with defined verification at SAT, or a first-article program in production. Known unknowns can be engineered around; discovered ones can only be paid for.
Trial and Acceptance Structure Across the Project
A straightening machine project normally has three evidence gates, and the RFQ package should already sketch all three. At the application trial, representative parts are run on reference tooling to validate the route and the correction window—this is where missing error-map data bites. At FAT, the actual machine demonstrates the agreed process against the agreed measurement method, with instruments and references identified; the detailed structure is in the straightening machine FAT checklist. At SAT, the same evidence repeats in the production environment, including the interfaces, handling and personnel that FAT cannot reproduce.
Keeping the three gates consistent is what makes them meaningful. The characteristic, gauge rule, support condition and sample count defined in the RFQ should be the ones used at FAT and again at SAT—each silent change between gates restarts the validation conversation and converts acceptance into negotiation. Where the customer’s own gauge is the final authority, the correlation between it and the machine measurement belongs in the plan explicitly, using the machine gauge versus customer gauge correlation framework, and the allowable difference needs customer quality approval before the machine is built, not after.
RFQ Review Questions
- Is the accepted characteristic defined in the same state in which the customer will inspect it?
- Are representative parts and variation available for a trial?
- Does the requested scope identify tooling, fixtures and material handling explicitly?
- Which inputs are assumptions rather than verified facts?
- What evidence will be required at FAT and SAT?
Add supplier-side questions that reveal engineering depth rather than catalog matching: What does the supplier want samples for, and how many? What would change their proposed route if the incoming error doubled? What do they measure during FAT, with what references, and how do they handle a mismatch against the customer gauge afterward? A supplier’s questions about your application are usually a better qualification signal than their answers about their machine.
For a selection boundary, see the straightening machine FAT checklist for what factory acceptance should contain, and the straightening machine cost page for how scope drives investment—automation level, measurement architecture and validation depth dominate the commercial conversation once the process route is fixed. Then contact StraighteningTech with the controlled package.
Frequently Asked Questions
How complete does the package need to be before sending an RFQ?
Complete enough that a supplier’s questions are about engineering choices rather than basic definitions. If the drawing, characteristic, acceptance method and representative samples exist, a serious supplier can scope the application and will ask for what remains. Sending earlier is fine—sending vaguer is not, because vagueness is what produces a machine quotation instead of an application one.
Why do suppliers ask for worst-case samples, not good ones?
Because the machine has to survive the production distribution, not the showcase part. Worst-case incoming bow, different lot conditions and near-limit geometry are where architecture limits and correction-window boundaries appear. Trials run only on good samples validate nothing about the days the machine was bought for.
What is the most commonly missing item?
The acceptance method. Requests frequently specify the geometry tolerance but not the gauge, support, span or state in which the customer will verify it—which means the machine is being scoped against an undefined target. It is also the cheapest gap to close: it already exists at the customer, it only has to be attached.
Should the RFQ state a budget?
A budget range constrains the solution space honestly and prevents wasted cycles on configurations that were never viable. The more useful discipline is stating scope priorities: which elements (measurement, automation, validation depth) are essential versus optional. That converts the commercial conversation from price comparison into scope engineering.
What interface data should be included for automation and traceability?
If the machine will operate inside a larger cell—robot loading, MES or quality-system integration, part identification and result storage—state it in the package with the protocol environment, data the machine must emit, and marking or traceability expectations. These requirements change controls architecture and cost materially, and they are far cheaper to specify at RFQ than to retrofit after installation.
Straightening Machine Cost and Price Drivers
There is no standalone price-list page for straightening machines because commercial intent overlaps ROI, selection scoping and the RFQ structure above. Use the straightening machine cost page to structure the cost drivers—workpiece envelope, measurement architecture, automation, tooling changeover and validation scope—without relying on unsupported price numbers quoted out of application context.
Related StraighteningTech Resources
See how automatic shaft straightening works for the closed-loop machine concept, straightening sample test and acceptance for trial evidence structure, and shaft straightness vs runout vs TIR for the characteristic definitions the acceptance section of your package should align with.