Shafts, sleeves & flanges
Fit and assembly holes on rotating/locating parts.
Open →PROCESS · GENERAL MECHANICAL
Standard Drill → Ream — The Default Path for Print-Critical Holes
If the print cares about diameter, roundness, or finish, treat drilling as preparation and reaming as the sizing cut. Choose a carbide drill that leaves a controllable pre-hole, then a reamer (carbide or PCD by material) to hit tolerance. This page is the shared playbook for general parts; shaft/flange and box/bracket pages apply it to part families.
DECISION
Drill-only vs drill + ream
- Drill-only when clearance holes or generous diameter bands are enough and position is fixture-controlled.
- Drill then ream when the print sells size, roundness, or finish—reaming is the sizing cut, not a salvage step.
- Position error is mostly a setup/fixture problem; reaming alone will not “fix” a wandering pre-hole.
Part-family details (shafts, flanges, boxes) live on their own pages—this page stays on process logic.
PRE-HOLE QUALITY
What a reamer inherits from the drill
- Taper / bell-mouth forces uneven stock removal and chatter risk.
- Walk / shift leaves the reamer fighting an offset centerline.
- Work-hardened skin (especially on some steels) accelerates edge wear on the first sizing pass.
- Chip packing in deep or blind holes damages both the drill exit and the ream entry.
Stabilize drill support, peck/coolant strategy, and runout before you blame the reamer.
ALLOWANCE MINDSET
Think method—not a universal table
Reaming stock depends on material, diameter, and how the pre-hole was made. XRZ does not publish one feeds/speeds or allowance chart for every metal. Use the engineering method on our Knowledge page, then confirm against your print:
TOOL MAP
Where XRZ products fit this path
| Step | Role | Product |
|---|---|---|
| Drill | Open hole / controlled pre-hole | Solid Carbide Drill Bits |
| Ream (general) | Size & finish after drill | Reamer tool |
| Ream (upgrade) | Non-ferrous + life/finish pressure | PCD Reamer |
| Combine stations | Only with a stable process window | Combination drill-ream—evaluate case by case |
FAILURE MODES
What usually shows up on the CMM or gauge
- Oversize — excess allowance, worn lands, or thermal growth
- Taper — poor pre-hole, guidance, or uneven wear
- Chatter marks — stick-out, holder, or stock too aggressive
- Built-up edge on aluminum — edge condition, coolant, and speed/feed balance
APPLY TO PARTS
Next: pick the family page
Boxes & brackets
Multi-hole patterns without batch drift.
Open →NEXT STEP — CORE TOOLS & RFQ
Specify the finished hole / face requirement, then choose the conversion path:
FAQ
Process FAQ
How much stock for reaming?
Use the Knowledge method—not one number for all metals. Start at allowance & pre-hole size.
Is an HSS drill good enough?
Often carbide wins on life and hole consistency in production batches.
PCD reamer after carbide drill on steel?
Material gate: PCD is not the default on steel; stay carbide/reamer-tool unless the application truly fits PCD.
Skip reaming to save cost?
Only if the print allows. Scrap and rework usually cost more than the second tool.
RFQ
Send print + current drill recipe
Include material, target Ø/tolerance, pre-hole method, and what fails today (oversize, taper, finish, life).