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HOLEMAKING · AUTOMOTIVE & EV

Engine & Transmission Holes — Precision Holemaking Without Guesswork

Powertrain holes fail from the wrong drill–ream stack, not from missing a brand name. Define material, diameter, tolerance, depth, and coolant, then choose a solid carbide drill series for the pre-hole and a reamer strategy for the finish. PCD reamers shine on non-ferrous precision holes; ferrous bores stay on carbide (or other agreed) paths—XRZ will say so up front on the RFQ.
HOLE JOBS

Hole jobs on engine & transmission parts

  • Oil and lubrication passages with depth and chip-exit risk
  • Locating pin and dowel holes that protect assembly stack-up
  • Bearing and bushing seats where diameter and roundness sell
  • Mounting and clearance holes that should not be over-tooled

We use generic feature language—no invented engine models. Housing-specific faces and windows live on Aluminum EV housings. Everyday shaft/flange holes → General Mechanical.

MATERIAL FORK

Material fork: aluminum vs cast iron / steel

MaterialDirectionNotes
Aluminum / non-ferrousCarbide drill → PCD ream candidatePCD value prop is strongest here
Cast iron / steelCarbide drill + carbide ream logicPCD is generally not XRZ’s default for ferrous
DRILL SERIES

Drill series selection cues

Start at the Solid Carbide Drill Bits hub and read series by material and coolant—not by one “universal” drill.

  • Match flute / coolant style to depth ratio and chip packing risk.
  • Stainless and hardened paths differ from general steel—use the matching series page.
  • Aluminum pre-holes still need controlled diameter so the reamer inherits a fair start.
COOLANT

Through-coolant—when it is worth it

  • Deep holes and stubborn chip exit benefit from through-tool coolant.
  • Blind oil passages often need a chip plan before you chase diameter with the reamer.
  • Details on coolant strategy belong in Knowledge and on the RFQ—not as a universal recipe here.
REAM OR NOT

When to ream

  • Ream when diameter, roundness, or finish is what the print sells.
  • Clearance holes with generous bands often stay drill-only if position is fixture-controlled.
  • Allowance method lives on Knowledge (“calculate reamer size”)—we do not invent a universal table here.
FAILURE MODES

Failure modes that show up on gauge

  • Oversize — excess allowance, worn lands, thermal growth
  • Taper — poor pre-hole, guidance, or uneven wear
  • Chatter — stick-out, holder, or aggressive stock
  • Poor prep hole — walk, bell-mouth, packed chips
TOOL MAP

Tool map + RFQ

StepRoleProduct
DrillOpen / controlled pre-holeSolid Carbide Drill Bits
Ream (Al / non-ferrous)Tolerance & finishPCD Reamer
Ream (ferrous)Carbide ream pathReamer tool
Combine stationsOnly with stable windowCombination drill-reamer
  • Material + hardness / casting notes
  • Ø, tolerance, depth, blind/through
  • Coolant and machine data
  • Volume and current scrap mode
FAQ

Engine & transmission holes FAQ

PCD on cast iron cylinder work?

Generally not XRZ’s PCD value prop—ask for the carbide path.

Step / multi-diameter holes?

Custom/step or combo—send the print.

How much reamer allowance?

Use the Knowledge method for calculating reamer size; no universal table on this page.

One drill for all metals?

No—series differ by material and coolant.

Same scenario: Aluminum EV housings · Combination tools · PCD aluminum · ← Hub

RFQ

Send the hole chart—we’ll fork aluminum vs ferrous correctly

Primary entries: solid carbide drills and PCD reamers for non-ferrous precision holes.

NEXT STEP — CORE TOOLS & RFQ

Specify the finished hole / face requirement, then choose the conversion path: