Knife Sharpening: Knives Per Belt And Belts Needed

Excel Formulas › Knife Sharpening

Belts are the biggest consumable in a sharpening shop, and running out mid-batch stops the job. Belt life in grinding minutes divided by minutes per knife tells you how many knives one belt handles; the batch size divided by that tells you how many belts to pull from the shelf.

Functions used (tap for the full reference guide):

The example

Three jobs with different belt life, knife times and batch sizes. Slower knives and bigger batches both raise the belt count.

The formula

Knives per belt rounds down (half a knife is not sharpened), and belts needed rounds up:

How it works

Here is the logic, one piece at a time:

1. B2/C2 is belt life divided by minutes per knife.
2. INT(...) rounds down to whole knives per belt.
3. D2/E2 divides the batch by knives per belt.
4. ROUNDUP(...,0) rounds up because a partial belt still has to be loaded.

Track real belt life: heavy serrated or damaged knives wear belts faster than clean chef knives.

Try it: interactive demo

Variations

Keep a spare belt

Add one to the belts needed for jobs where a belt may tear.

Cost per knife

Divide the belt price by knives per belt.

Pitfalls & errors

Practice workbook

Frequently asked questions

Related formulas: Knife Sharpening: Ticket Total by Blade Type · Knife Sharpening: Tiered Volume Price · Embroidery: Machine Run Time From Stitches

Function references: INTROUNDUP