Aerospace fastener hole machining
Structural fastener holes in aluminum, titanium and composite stacks — interference fit, exit condition and hole-to-hole consistency.
Open fastener holes →SOLUTIONS · AEROSPACE & DEFENSE
Aerospace & Defense — The Process Is Frozen Before the Tool Is Chosen
On an aerospace part the reamer is rarely the free variable. Once a hole process is qualified against a part number, changing the tool means re-qualifying it, so the useful question is not what cuts fastest but whether a tool can hold the qualified window and be documented doing it. Two things follow from that: a material stack turns one hole into two problems, because a CFRP/Ti fastener hole has no single exit condition, and the record is part of the deliverable, not paperwork written afterwards. HENTRY works from your drawing, your qualified process and your inspection plan — not from a catalogue page. Choose the subpage that matches your part, or send the print with the qualification requirement marked.
WHO THIS IS FOR
Shops that have to answer for the process, not just the part
- Airframe structure and detail-part suppliers drilling fastener holes in aluminum, titanium and composite stacks
- Engine and actuation manufacturers finishing bores in casings, seal lands, bushings and fuel or lube system components
- MRO and spares operations that must reproduce an already-approved process at low volume
- Typical stocks: 2024, 7050 and 7075 aluminum; Ti-6Al-4V; 15-5PH and 17-4PH stainless; Inconel 718; CFRP and CFRP/Ti stacks
If your part is a general machined bracket with no qualification gate behind it, the General Mechanical hub gets you a quote faster. This hub assumes somebody will eventually ask for the process record.
CORE APPEAL
Three constraints that outrank cutting speed
In aerospace the tooling decision is usually made second. These three constraints decide what is even allowed on the table:
- Qualification lock. A different tool geometry is a different process. If the part is already qualified, the honest options are a tool that holds the existing window or a change justified by a defect you can name and measure.
- Stack mismatch. Composite and metal in the same hole means two chip mechanisms, two heat paths and one exit condition. A drill that is clean on the composite layer usually pushes the damage into the metal, and the reverse is equally true. The layer you enter first and the support behind the exit are tool decisions, not operator preferences.
- Documentation. Batch identification, drawing revision, geometry record and agreed inspection points travel with the parts. A tool that cannot be reproduced identically across batches is a liability dressed as a saving.
This hub stays at programme level. Interference-fit detail, bore-by-bore feature maps and traceability field lists live on the three subpages — they are not restated here.
PROCESS SNAPSHOT
Tool map for aerospace work
| Need | Common path | HENTRY entry |
|---|---|---|
| Open a fastener hole through a stack | Carbide drill sized to the stack, through-coolant once depth or layer count demands it | Through-Coolant Carbide Drills |
| Bring the hole to fit size | Ream after a controlled pre-hole; aluminum and non-ferrous can take PCD, titanium and nickel normally stay carbide | Carbide Reamer · PCD Reamer |
| Fillets, edge breaks, contour work | Corner-radius or ball-nose geometry matched to the fillet callout | Corner Radius End Mills · Ball Nose End Mills |
| Heat-resistant casings and rings | Carbide with coating and edge prep matched to the alloy rather than to a general-purpose grade | Solid Carbide Drills · Carbide End Mills |
| Hard-turned or hardened features | CBN where hardness rules out carbide entirely | CBN / PCBN Inserts |
SUB-SOLUTIONS
Choose the page that matches your part
Aerospace engine & actuation bores
Casings, seal lands, bushings and fuel-system parts in heat-resistant alloys and thin-wall rings.
Open engine bores →Aerospace tool traceability
What a tool change actually costs: first-article, batch identification, drawing revision and tool-life records.
Open traceability →WHEN TO LEAVE THIS HUB
Use a different scenario when the job changes
- The alloy physics is the problem — heat, chip control and exit burr in titanium or nickel, with no qualification gate → Difficult Materials hub.
- Plain locating holes — brackets, flanges and covers without a fit or a record requirement → General Mechanical hub.
- High-volume aluminum housings on line takt — EV and transmission work where cycle time outranks documentation → Automotive & EV Powertrain hub.
- Fluid-power bores with a moving element inside — valve bodies, spool bores and manifolds → Hydraulic & Fluid Power hub.
RFQ CHECKLIST
What to send for an aerospace tooling review
- Drawing and revision, with the qualified or target process stated
- Material and stack sequence — which layer the tool enters first
- Hole schedule: Ø, tolerance class, depth, perpendicularity, chamfer or countersink
- Fit or interference requirement, and how it is verified today
- Machine, holder, stickout, measured runout and coolant supply
- The inspection plan and acceptance record your customer asks for
FAQ
Quick answers before you RFQ
Can you supply a tool for a process that is already qualified on another supplier's geometry?
Usually yes, and the review starts from the qualified geometry rather than from our standard range. Send the existing tool drawing or a measured sample with the part print — matching a qualified window is a different job from designing a new one, and it is quoted as such.
Do you hold aerospace quality certification?
We do not publish a certification claim, and we will not imply one. If your quality plan requires a specific approval, state it on the RFQ and we will confirm what can and cannot be supported before any quote is issued. Our published position on evidence is set out on Manufacturing & Quality Evidence: workshop images show resources, not a certification result.
Is PCD ever right in aerospace?
Yes, but narrowly. It belongs on aluminum and non-ferrous features where finish or wear life is the driver. Titanium, nickel and most structural steels stay on carbide; putting PCD there is a cost increase with no process benefit.
How do you approach a CFRP/Ti stack?
As two holes that happen to share an axis. The composite layer cares about fibre pull-out and delamination at entry and exit; the metal layer cares about heat and burr. Drill geometry, feed schedule and the support behind the exit are reviewed together — the fastener hole subpage covers that in detail.
Where does the general alloy cutting data live?
On the Tough-Alloy Holemaking page under Difficult Materials. This hub covers what the aerospace programme adds on top of that physics; it does not repeat it.
ENGINEERING QUOTE
Send the print with the qualification requirement marked
Primary tooling entries for this hub: solid carbide drills, carbide reamers and through-coolant drills, with corner-radius and ball-nose geometry for contour work. Certification requirements are confirmed before quoting, never assumed.