The In-House Sharpening Question
At some point, most shops ask whether they should be sharpening their own drills. The answer isn't simple, because it depends heavily on volume, available skill, the quality standard you need, and what your time is actually worth. This post walks through the real options — from a basic bench grinder setup to dedicated drill grinding machines — and helps you figure out what setup actually makes sense for your operation.
Option 1: The Off-Hand Bench Grinder
A bench grinder with a dressed aluminum oxide wheel is what most small shops already have. In skilled hands, it can produce a serviceable drill point. The cost to add sharpening capability: essentially zero if you own a grinder, maybe $80 to $200 for a quality bench grinder if you don't.
The skill requirement is real, though. Off-hand drill sharpening is one of those tasks that looks simple but takes genuine practice to do consistently. The critical elements — matching the point angle, balancing the two lips to equal length, achieving correct lip clearance without grinding away too much body — are all done by eye and feel. A new machinist can learn it, but not in an afternoon. Expect a few weeks of practice before results are reliable.
The other issue is consistency. Off-hand sharpening produces variable results, especially on the balance between the two cutting lips. An unbalanced drill — where one lip is longer than the other — cuts oversize holes, loads unevenly, and dulls faster on the longer lip. For general shop work in mild materials, slightly unbalanced drills are often "good enough." For precision holes or harder materials, they're not.
Off-hand grinding works best for: large drills (3/8" and above) where there's enough material to see what you're doing, frequently used common sizes where practice builds familiarity, and shops where precision tolerances aren't the primary concern.
Option 2: Dedicated Drill Grinding Attachments
Several manufacturers make drill grinding attachments or fixtures designed to mount on a standard bench grinder. These hold the drill at the correct angle and guide the rotation to produce consistent geometry. Cost runs from $40 for basic plastic fixtures up to $200 or so for better metal fixtures with angle adjustment.
These attachments solve the consistency problem for standard point angles and common sizes. They're limited on range — most handle 1/8" to 3/4" or similar — and they don't accommodate split points, parabolic flutes, or specialty geometries. For a shop doing repetitive work in a narrow size range with standard geometry, a fixture is a solid upgrade from pure off-hand grinding at reasonable cost.
Option 3: Dedicated Drill Grinders
A dedicated drill grinder — the class of machine represented by the Darex E90, the WinsloMatic, or similar — is a different category. These are purpose-built machines with precision collets, calibrated angle settings, and wheel geometry designed specifically for drill points. They produce consistent, measurable results across a wide size range and handle web thinning properly.
Cost: entry-level dedicated drill grinders start around $600 to $800 new for smaller machines, and WinsloMatic-class or Darex units run $1,500 to $4,000 depending on size range and features. Used machines are available and often represent good value, but require inspection — wheel condition, collet wear, and spindle runout all affect results.
A dedicated grinder is the right choice for: shops running high drill volumes, operations where consistent geometry matters (tight tolerances, hard materials, CNC work), and situations where the time cost of suboptimal drills exceeds the machine investment. If you're throwing away $200 or more per month in drill replacements that could have been resharpened, a $1,500 machine pays back in under a year.
Skill Required vs Equipment Cost: The Honest Tradeoff
There's an inverse relationship between equipment cost and required skill. Off-hand grinding: nearly free equipment, significant skill required. Quality drill grinder: significant equipment cost, minimal skill required after initial setup. The fixture approach sits in between on both axes.
Most small shops underestimate the skill side of the equation. Off-hand sharpening looks easy because experienced machinists make it look easy. Teaching a newer employee to off-hand grind consistently takes months, not days. If your shop doesn't have a skilled grinder already, factoring in training time often changes the economics in favor of a machine or mail-in service.
The Hybrid Approach: In-House Plus Mail-In
The approach that makes sense for many small to mid-size shops is a deliberate split between what you sharpen in-house and what you send out.
In-house: large common sizes where off-hand grinding is manageable (3/8" and up), drills used constantly where you have the skill to do it quickly, and quick touch-ups on drills that just need a small correction.
Mail-in: small diameter drills where precision matters and off-hand results are inconsistent, any drill where geometry precision affects part quality, high-value jobs where drill performance is a variable you want controlled, and batch resharps where the time to do them in-house exceeds the mail-in cost.
Mail-in resharpening from a service like MachinistPost runs a fraction of replacement cost per drill. For shops doing their own sharpening on obvious stuff but sending out anything critical or small, the hybrid approach often produces better overall results at lower total cost than trying to do everything in-house with equipment that isn't quite right for the job.
What You Actually Need to Get Started
Minimum viable setup for occasional in-house sharpening: a 6" or 8" bench grinder ($80-$150), a dressed aluminum oxide wheel (already standard on most grinders), good lighting directly on the work, and a drill point gauge to check geometry after grinding ($15-$25). A drill holder fixture adds consistency for an additional $40-$80.
For a real sharpening station: add a drill stand or vise for holding drills during inspection, a loupe or magnifier for checking small drills, and a dedicated wheel dresser to keep the grinding wheel flat and true. Total cost under $300 for a functional setup that handles most shop needs reasonably well.
For precision work at volume: budget for a dedicated drill grinder. The math usually works out — especially when you add up what you're spending on replacement drills that could have been resharpened for a fraction of the cost.