A provider’s equipment list identifies possible enquiries. Selecting a service requires a defined supplied blank and delivered result, with evidence for the actual bore requirements.
Read the service scope rather than a general ranking
TBT’s German subcontracting page describes single and series production, with additional milling and threading work. This is a supplier’s offered scope; it does not establish a ranking of BTA providers or qualify a different part.
Ask the proposed provider to identify the operations included for the actual drawing. Drilling only, a route including finishing and a package including associated features are different services. A lower quotation can reflect an earlier delivery endpoint rather than greater efficiency.
Request evidence tied to the feature
Retain representative material, blank condition, tool configuration and inspection coverage with any application comparison. A machine’s nominal capacity is not the measurement result for a delivered bore. A certificate also needs its applicable scope and issuer; a statement that the shop works in an industry does not identify the required qualification.
For a first enquiry, the RFQ worksheet below collects drawing revision, incoming part, quantity, required characteristics and included charges. Avoid requesting a price for a nominal diameter while leaving the datum and texture requirements for later.
Keep the acceptance and exception route visible
Agree the record package associated with delivered parts, including uninspected features, rework and any agreed acceptance rule. A statement that the program completed does not establish that every required characteristic was assessed.
The provider comparison should preserve those same requirements across offers. Use BTA quality planning for the inspected endpoint and accepted-batch cost for the denominator. Evidence can support a decision once the compared services deliver the same specified result.
Revision note
October 8, 2026: revised the technical explanation and connected reading after source review. Original publication date and URL retained.
