
Belt Buyer’s Guide: Which Abrasives to Actually Buy
Belts are the single biggest recurring cost in this hobby, and buying the wrong ones wastes money twice: once on belts that wear out fast, and again on…

Abrasives
ApexUltra at 64-67 HRC grinds like a stubborn 52100: feather passes and constant dunks to protect the temper, then a diamond-assisted routine at the bench.
1 min readWritten by Rich LinvilleFree to read
ApexUltra sits deliberately between worlds, and the shop experience matches: harder work than the classic carbon steels it forges like, far friendlier than the powder stainless class it cuts like. The tungsten that buys its wear resistance collects a modest tax at every abrasive step — pay it with sharp consumables and cool habits.

Fresh ceramic belts make annealed ApexUltra feel like slightly stubborn 52100; worn belts make it feel like punishment — the carbides decide which shop you run. Hog annealed as always. Post-heat-treat is the real discipline: at 64-67 HRC, edges are thin, hard and expensive — sharp 120-220 ceramics, feather pressure, dunk cadence like a metronome. A blued ApexUltra edge hurts three ways: the temper, the re-treat, and the bar price. Finishing: it hand-sands well for a carbide steel and takes a handsome satin; hamon is not its game (that is W2 and 26C3 territory) but a clean etch shows a quiet quench line on differentially treated blades.

Good stones work; diamonds work better. The tungsten/vanadium carbide load is low enough that quality waterstones cut it honestly — slower than 26C3, faster than any PM stainless — and a diamond progression simply makes the 65-HRC edge routine. Finish on a strop with fine compound: at this hardness the apex stabilizes beautifully and push-cut keenness holds. Angles: the whole point of the steel is running 10-14 dps kitchen edges at hardness that keeps them stable — grind the thin geometry it was engineered for, per the kitchen angle guide.

Budget roughly 1.5x classic-carbon shop time and premium belt consumption — then remember the finished blade’s spec sheet writes the listing. ApexUltra work is flagship work; the shop tax is part of the story the customer is buying.

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Same bench
I machine the parts, hand-assemble, track and test Torus grinders in Sterling, Illinois. Most orders ship in seven to ten business days from time of order.

Current dual-axis platform with a fiber-laser-cut 6061 chassis and single-knob tracking.

Current dual-axis platform with a steel chassis, more mass and less vibration.

Prior-design aluminum chassis, 90-degree tilt and 1.5-inch tooling arms.

One-man shop
I answer my own email. Tell me the steel, the machine and what it is doing, and I will tell you what I would try next.