Drill Bit Resharpening vs. Buying New: The Actual Math for Machine Shops

The question comes up in every shop eventually: is it actually worth the effort to resharpen, or should we just buy new? The answer isn't the same for every drill size or every shop. Here's how to run the numbers for yours.

THE BASIC COMPARISON

Take a standard 1/2" HSS jobber drill. New, from a domestic supplier like OSG or Nachi, runs $18–$28 depending on grade. A mail-in regrind from MachinistPost runs $4.25 per bit (Standard tier) or $3.00 in volume.

That's a 75–85% cost reduction per resharpen compared to buying new.

Over 5 resharpenings (a conservative estimate for a 1/2" bit): the bit cost the original $22 purchase plus $4.25 × 5 = $21.25 in regrinds = $43.25 total for 6 usable lives versus buying new 6 times at $22 each = $132.

You spent $43 to get what would have cost $132 in new drills. That's $89 saved per bit for a drill size you probably use in multiples.

WHERE THE NUMBERS CHANGE

Small drills flip the math. A 1/8" drill costs $2–$4 new. MachinistPost's minimum per-bit rate is $2.75 (Standard tier, small-batch). At that price point, resharpening still saves money — but the margin is smaller and the handling logistics (collecting, packaging, sorting) add real cost in labor.

Most shops find the economics of resharpening improve sharply above 3/8" diameter. Below 1/4", the case-by-case analysis matters more: are you using them in large quantities? Are they going into expensive materials where bit geometry matters? Are they from a premium domestic supplier worth preserving?

THE HIDDEN COST MOST SHOPS MISS

New drill bits — especially imported ones — often don't arrive at factory geometry. Point angle inconsistency, unequal lip lengths, and non-concentric chisel edges are common on low-cost bits. A resharpened bit from a precision grinder comes back to a tighter geometric tolerance than many bits arrive new.

The argument "I'll just buy new" implicitly assumes the new bit performs at least as well as the resharpened one. For domestic name-brand HSS at full price, that's usually true. For imported bits at commodity pricing, the resharpened bit often outperforms.

VOLUME CHANGES EVERYTHING

MachinistPost pricing tiers: Standard ($4.25/bit), Pro Member (volume discount, $2.75+/bit). If your shop uses 20+ drills of 3/8" and above per month, the Pro Member program gets the cost low enough that the math heavily favors sending everything rather than buying any new bits in those sizes.

Run this calculation for your top 5 most-used drill sizes. Use your actual cost of new bits from your current supplier. The answer usually surprises shops that have been defaulting to new.

← Back to Blog