吃瓜tv 路 Connector specification 路 acceptance worksheet
Press-fit PCB holes: start with the connector specification
Compare finished-hole and board-thickness windows with the connector application drawing. Prepare plating, support and inspection requirements for review.
Preliminary files and open process questions are welcome.
What is a press-fit hole in a PCB?
A PCB press-fit hole is a plated hole intended to receive a specified press-fit connector pin under a controlled assembly process. For a compliant-pin connector, the pin鈥檚 elastic feature and the finished plated hole work as a system. The required hole interval comes from the exact connector鈥檚 application specification, together with board thickness, plating, finish and insertion requirements.
This is different from selecting a generic mechanical dowel-pin interference fit. A simple pin-diameter-minus-hole formula cannot qualify a compliant electrical connection or predict the insertion force of a complete connector. A board can have a plausible nominal hole diameter and still be unsuitable because its tolerance, copper plating, finish, support or assembly process is wrong.
Start with the connector part number and current application drawing. Then compare the complete PCB finished-hole range with the allowed range. This page provides that dimensional comparison and a release checklist. The broader PCB DFM review can reconcile these requirements with the rest of the board artwork and fabrication package.
Translate the connector document into a PCB requirement
Distinguish three quantities: drill-tool diameter, finished plated-hole diameter and the connector鈥檚 specified hole interval. The fabrication process transforms the drilled hole through preparation, plating and finishing. The pin encounters the finished surface, not the original drill-tool size. Ask the fabricator to propose a controlled route for producing the required finished condition.
Connector requirements may specify more than one construction or board-thickness range. Verify that you are using the correct row for the actual pin and connector variant. Similar housings can contain different contact systems, and a footprint library may omit a manufacturing note that appears in the application document. Resolve conflicts before ordering boards.
| Requirement | Record in the manufacturing package | Avoid this substitution |
|---|---|---|
| Connector identity | Exact part, variant and document revision | A generic connector family name |
| Hole dimension | Finished minimum and maximum with unit | Nominal drill size alone |
| Plating and finish | Required system, thickness basis and restrictions | Colour or an unspecified 鈥減lated hole鈥� |
| Board thickness | Allowed finished interval at the interface | An average panel measurement |
| Hole location | Pattern, positional requirements and datum | Nominal pitch without pattern alignment |
| Insertion process | Approved tooling, support and verification | Generic mechanical-fit force arithmetic |
Keep the connector document available during the quotation. If the customer drawing and the connector application requirement disagree, mark the issue explicitly. A manufacturing quote should not silently choose which requirement to ignore. An early review can prevent a board purchase that is dimensionally repeatable but incompatible with its connector.
Compare complete dimensional windows
The worksheet tests containment, not just overlap. It compares both ends of the PCB finished-hole interval with the connector-approved interval, then repeats the comparison for board thickness. A negative margin identifies the boundary that exceeds the entered requirement. The result says 鈥渄imensions only鈥� even when every margin is nonnegative, because plating and assembly conditions remain separate.
Press-Fit Dimensional Window Comparison
For an invented example, a connector-approved hole window of 0.98鈥�1.06 mm contains a PCB window of 0.99鈥�1.05 mm, leaving 0.01 mm at each boundary. A PCB window of 0.97鈥�1.05 mm would overlap the approved window but fail containment at the lower end. These values demonstrate the logic and must not be copied as a real connector specification.
Measurement uncertainty and any required guard band are not included automatically. If the acceptance plan reserves part of the connector window for uncertainty, enter the agreed manufacturing limits and document that decision. Matching nominal values is not enough, and a favorable calculation does not eliminate the need to verify the delivered hole condition.
Specify the conductive hole wall and surface condition
The compliant feature interacts with the hole wall during insertion. Copper plating, surface finish and their condition affect that interface. Use the selected connector鈥檚 requirements and a fabricator-approved process rather than assuming any solderable PCB finish is acceptable for every press-fit system. Keep the hole finish requirement distinct from the finish used on other component lands when necessary.
The PCB surface-finish guide helps organize finish choices, but the connector specification remains the controlling source for its hole interface. Likewise, a requirement expressed as a local minimum plating thickness should not be replaced by a panel-average value. Agree the measurement location, method and sampling so that the quoted evidence addresses the actual requirement.
Also review hole preparation, debris, damage and any later process that could alter the finished interface. Avoid unapproved reaming or cleanup that changes the conductive barrel. A hole that can physically accept a pin is not necessarily an electrically reliable press-fit hole. Any proposed repair or process deviation needs a documented engineering disposition.
Treat the complete connector pattern as a mechanical interface
One hole may be within its diameter limit while the full pattern is out of position. Hole-to-hole location, board registration, connector alignment features and the assembly datum all contribute to insertion. Review mounting features and keepouts near the connector so that fixtures can locate and support the board without contacting vulnerable components.
Board bow and local thickness variation can also affect seating and support. Discuss where the connector loads enter the board and whether the underside is accessible. Components, solder joints, copper features and protruding leads can restrict a fixture even when the top-side footprint looks clear. A useful assembly drawing shows the actual working envelope, not just a connector courtyard.
The worksheet intentionally does not calculate positional tolerance or aggregate insertion force. Those tasks depend on the connector, pin count, tool and support arrangement. Add the relevant dimensional and process records to the review instead of using a universal formula that hides these dependencies.
Qualify insertion with the actual connector and tooling
explains compliant contact systems as an interaction between the contact and PCB. This supports a part-specific approach; it does not authorize transferring one product鈥檚 hole size or process limits to another connector.
The selected connector鈥檚 assembly document should define the tooling and seating requirements that apply. For example, includes support, insertion and seating instructions for that product. Its numerical limits are product-specific and are not general PCB press-fit tolerances.
Plan board support, tail clearance, connector alignment and the insertion load path before a trial. A fixture should support the intended region without forcing populated components or delicate solder joints to carry the load. Check that the tool acts on the connector where its manufacturer permits, rather than applying force to an incidental housing feature.
Where force or displacement records are part of the agreed process, define what trace is recorded and how limits are established. A peak force alone may hide an abnormal seating path. An unexplained force change deserves investigation rather than automatic acceptance because the connector appears seated. Rework and reinsertion permissions should also come from the applicable connector and product requirements.
Separate board acceptance from assembly acceptance
Bare-board verification should address finished-hole dimensions, relevant plating and the other agreed drawing requirements. Assembly verification addresses connector seating, visible damage, alignment and the specified process or electrical checks. These are complementary records. A board report does not establish that insertion was correctly performed, and a seated connector does not prove the hidden hole wall is acceptable.
Agree how samples represent the connector hole population. If sectioning is used, identify the feature and orientation so that the result answers the plating question. If gauges are used, define their suitability for the required dimension and condition. Do not assume one simple gauge can certify plating thickness, roundness, position and finish simultaneously.
For product qualification, select environmental and mechanical evidence according to the application and applicable requirements. The is a starting point for identifying relevant board and assembly documents; the order should name the agreed revisions and acceptance criteria. A generic 鈥淚PC compliant鈥� statement is not a substitute for the connector application specification.
What affects a press-fit PCB quotation?
The quotation may reflect a tighter finished-hole process window, plating requirements, special inspection, test coupons, controlled board thickness or additional engineering work. The practical cost also depends on hole population, pattern, panel utilization and whether the interface can share the normal board processing route. There is no universal surcharge that accurately prices every press-fit footprint.
Separate bare-board fabrication from connector insertion and qualification. A low board price may exclude the process development or evidence needed for the finished assembly. Ask which items are included: connector supply, fixture design, trial insertion, measurement reports, assembly records and any product-specific qualification. Compare equivalent scopes before choosing a supplier.
Press-Fit PCB Holes Budget and RFQ Brief
The budget brief accepts your own dated allowances. It can also produce a technical request with costs left blank. Changing quantity, scope, currency or source clears old allowances so that a previous price is not silently applied to a new connector requirement. The tool does not compute a press force or claim a calibrated market price.
Prepare a connector-to-board review package
Send the exact connector part and application document, fabrication revision, drill data, finished-hole table, board-thickness interval, plating and finish notes, hole-position requirements and requested quantity. Include the assembly arrangement if 吃瓜tv is also reviewing insertion or the populated board. A marked drawing is useful for identifying which holes are press-fit and which are ordinary soldered through holes.
Identify open questions before the quote is finalized. Examples include the approved finish, measurement method, access for underside support or a conflict between the connector drawing and existing artwork. State who owns each decision. This helps separate a manufacturing clarification from a product-design change that requires customer approval.
Return to PCB manufacturing for the complete board build or PCB assembly when the scope includes population and connector insertion. The same released interface specification should travel with both requests so that fabrication and assembly evaluate the same requirement.
Press-fit PCB questions before ordering
Can the tool select a hole size from my pin diameter?
No. Use the selected connector鈥檚 approved finished-hole interval. Compliant-pin geometry and its qualification cannot be reduced to a generic pin-minus-hole calculation. The worksheet compares documented windows after those requirements are known.
Is a drill file enough to specify a press-fit hole?
It is part of the package, but the finished-hole requirement, plating, finish and applicable connector document must also be clear. The fabricator needs to distinguish the requested finished condition from the manufacturing drill input.
If the two tolerance ranges overlap, is the design acceptable?
Not necessarily. Some boards within the PCB range could fall outside the connector-approved range. The complete PCB interval must meet the agreed limits, including any separately defined uncertainty or guard-band policy.
Can a press-fit connector be removed and installed again?
Do not assume that it can. Removal and reinsertion can affect the contact and hole interface. Follow the connector supplier鈥檚 instructions and the product鈥檚 approved repair process, with the required inspection and disposition.
Review your press-fit hole specification
Send the fabrication revision, stackup, quantity and the specific process question. Include connector or package requirements, mechanical drawings and the inspection evidence you need.
Tool use is optional. Attach any downloaded brief manually; Contact does not automatically receive worksheet inputs. References reviewed September 2026. Illustrations are explanatory, and photographs are not process qualification records.