DMT D6FC: problems, parts and running costs

Checked: 2026-10-17

Summary

The DMT D6FC is a 6 x 2 x 0.25-inch double-sided diamond bench stone — Coarse 45 micron / 325 mesh on one side, Fine 25 micron / 600 mesh on the other, about 0.86 lbs [8]. The usual complaints are physical rather than abrasive: it ships without non-skid feet and slides on a smooth bench, the 0.25-inch profile is thin for hand work, and one owner doubts current production matches older stones. There are no consumables at all — no oil, no flattening, no parts — so yearly running cost is effectively zero. It is strong value at or under $40, fair at the $59.99 Sharpening Supplies price, and weak above $80.

Common problems and fixes

Slides on smooth benches — the double-sided design has no non-skid rubber feet; DMT’s catalog lists rubber feet on single-sided models only, and a European retailer states that all models except the double-sided ones have them. Fix: set the stone on a mat or holder. [11][7]
Thin profile — at 0.25 inches the stone is thin: one owner wanted it to sit taller for hand clearance and was not comfortable using it as a hand-held sharpener. Fix: use a holder or raise the stone. [5]
Shorter than recommended for general use — a sharpening retailer recommends an 8-inch or larger stone for general sharpening, so the 6-inch plate is a compromise on larger blades. [10]
Durability doubts about current production — one r/sharpening user reports current-production stones are “nothing like the superb stones” from 10+ years ago; this is a single-owner signal, while DMT’s FAQ says a properly used stone lasts several years. [3][4]
Dry use shortens stone life — a retailer’s buying guide warns that dry use can shorten stone life; use water as the lubricant. [9]
Do not use it to flatten other stones — DMT’s FAQ says non-“Dia-Flat” stones should not be used to flatten waterstones, Arkansas and synthetic stones, even though the D6FC product page claims it can flatten conventional and water stones. [4][1]

Parts and consumables

No replaceable parts or consumables reported. The D6FC is a passive abrasive plate with no moving parts: no oil is needed, no re-flattening is required, and when the diamond surface wears out the whole stone is replaced. Clean it with scouring powder to lift metal sludge. [2]

Yearly running cost

Zero in consumables: no oil, no flattening plates and no replacement parts; water works as a lubricant at no cost and occasional scouring powder is the only supply. DMT says a properly used, cleaned and stored diamond sharpener lasts several years, so the cost is the purchase price spread over years of use. No per-year dollar figure was reported in the research. [4][2]

When it is a good buy

Store prices at the October 2026 research pass: DMT direct lists the D6FC at $75.99 (sold out on DMT’s site); Sharpening Supplies lists it at $59.99, on sale from $75.99; Home Depot lists it in the $34-38 range; Carbatec lists it at $149.00 AUD. [1][6][5][12]
Value thresholds from the research: strong at or under $40, good from $41 to $60, fair from $61 to $80 where you pay a premium for the DMT brand and US manufacturing, weak above $80. [1][6]
Named alternatives: a larger DMT 8-inch or 10-inch DuoSharp when you sharpen bigger blades or want the recommended general-use size; a water stone set with a flattening plate when you want a mirror finish and do not mind the maintenance. [10][2]