Bearings and locks by system

This page picks up where the scale comes off. It covers what you find under it on each bearing system you will meet at the bench, how to clean, oil and inspect each one, then does the same for the three lock types and the parts every lock shares. For the take-down itself, see Disassembly, reassembly and pivot tuning; for which models carry which system, the bearing systems page.

A few rules hold for every system. Clean with 91–99% isopropyl, never a water-based cleaner. Keep the two sides’ bearings apart from the moment the scale lifts until they go back in. Handle balls and rollers with tweezers, not fingers. Let every part dry fully before any oil goes on. And give the knife a few hundred cycles after reassembly before you judge the result; the action settles over that stretch.

Bearings by system

SRBS

An SRBS knife carries a single row of balls on each side. Early knives came both ways, loose or caged, so look before you lift: if the balls are loose, have your tray under the knife and raise the scale straight up. Count the balls on each side as they come out and check the count when they go back; a ball can hide in a recess or cling to the scale.

Clean the balls in a small dish of isopropyl, agitate them gently for a minute, lift them out with tweezers and let them dry. If the race has a cage or insert, leave it in place and clean around it. Wipe the races in both scales with isopropyl on a cotton swab and blow out the channel.

Oil with a light knife-pivot oil, KPL or Nano-Oil 10wt. One or two small drops on the seated balls is enough; roll them around the race to spread it and wipe off anything that migrates. Before reassembly check each ball for flats, pitting or discoloration, and the race floor for scoring or embedded grit.

MRBS

MRBS is the serial standard: several rows of loose 1.5 mm balls riding in races machined into the scales. Photograph the arrangement before you disturb it and lift the scale slowly; some balls stay in the blade-side race and some come up with the scale, and the photo tells you which row each came from. Keep the rows separate during cleaning as well as the sides.

You can clean MRBS two ways. Individually: balls into isopropyl, agitate, out with tweezers, dry, inspect. In the race: leave the balls seated, flood the race with isopropyl, work a cotton swab gently around the rows, blow out the debris and solvent, and repeat until the swab comes up clean. Either way, leave any race inserts in place and don’t scratch the channels.

Oil as for SRBS, lightly and evenly on each row. Excess oil holds pocket lint, which is what makes an MRBS action go gritty in the first place. On inspection confirm the count per row and look for a ball that sits higher than its neighbors, which means debris under it or a damaged ball.

SRRBS

SRRBS knives, the Custom Division and Sprint Run system, carry a single row of loose cylindrical rollers on each side. They are not caged. When the scale lifts, expect rollers to be free to move, and if a side stays seated, leave it seated and clean it in place.

Rollers want more care than balls. A roller that goes back in skewed or on its end spoils the action. Work over a light-colored mat, lay the rollers out in the order they came from the race, use non-magnetic precision tweezers, and keep each side’s rollers in their own container. Clean them together in a dish of isopropyl, with a soft brush for stubborn debris, blow them dry at low pressure and let them finish drying before you handle them again. Clean the race channels thoroughly.

Use less oil than on a ball system. A lighter oil, Nano-Oil 5wt, is the usual choice: a single small drop across the seated rollers, spread by rotating the blade gently, then wipe away any excess. On inspection roll each roller on a clean flat surface and watch that it rolls true, look for flats or nicks at the ends, and confirm every roller sits flat in its channel before the scale goes back on. Custom Division scales carry finish work, so clean the outer titanium and anodized surfaces with a microfiber cloth and a mild, pH-neutral cleaner, and keep the solvent to the race channels. If the action after service isn’t what it was, the cause is almost always a roller out of orientation; see Troubleshooting after reassembly.

DRRBS and MRRBS

The two roller systems above SRRBS sit on the custom tier, with DRRBS also on a few early Custom Division pieces: DRRBS carries two rows of rollers per side, often over hardened steel underlays set into the titanium, and MRRBS carries several rows of uncaged rollers at tighter tolerances still. Leave them to the workshop. If you do open one, photograph it from several angles before separation, keep the assembly together during cleaning rather than pulling individual rollers, and oil as for SRRBS. All the rollers are loose. Full customs also carry the duck foot pivot, which is never found on Custom Division; note its orientation and seating before it comes out. For any real problem with a DRRBS or MRRBS pivot, contact the factory or the dealer who sold the knife; see Service, warranty and storage.

Locks by type

Frame lock

The F95, Hati, NeOn, Quantum and MidiQ Custom Division are frame locks. Clean the lock bar face and the matching face on the blade tang with isopropyl on a cotton swab, and clean the relief cut so the bar flexes freely. Nothing abrasive touches either face, carbidized or not. Look for an even wear pattern and for galling or bright smearing, which means the interface has been running dry or dirty.

Leave the tension alone unless the lock is misbehaving. Note where the lock bar sits on the tang before disassembly and compare after; if the two match and the lock holds, there is nothing to adjust. When a change is needed, make it small: bend the bar inward for more tension or outward for less, one minimal move at a time, and test after each. Titanium work-hardens with repeated bending, so every extra flex costs you.

Service the lock bar stabilizer at the same time. Clean its threaded hole and the disc face, check the screw isn’t stripped, and on reassembly put a trace of blue 242 on the screw threads and set it so it doesn’t drag on the lock bar.

For lockstick, escalate in order and stop at the first step that works: clean both faces; give the interface a break-in period, since a fresh lock face often sticks until the two faces mate; apply a trace of graphite (a pencil lead rubbed on the tang face); apply Gunny Glide; and only as the last step, a heavier oil on the contact patch alone. Keep graphite out of the pivot.

Liner lock and the 111’s inset lock

The F3 is a liner lock, the Stellar and the Astrum are liner locks with an apron, the Sinkevich Fat Strip, Fit Strip and Skinny Strip are liner locks, and the 111’s liner lock carries a stainless insert at the contact face, which is what collectors call the inset lock. Clean it as you would a frame lock: isopropyl on a swab across both faces, debris out of the lock bar channel, and a check that the liner travels freely.

On the 111, clean around and under the edges of the insert without removing it. If it has to come out, record its exact position first and confirm it is seated and secure when it goes back; an insert that has shifted shows up as a change in where the lock bar lands on the tang. Tension on a liner lock is adjusted as on a frame lock, with more caution, and the 111 rarely needs it.

Chores every lock shares

The detent ball and its path. Clean the ball with isopropyl on a swab, clear the detent hole in the blade, and put a trace of light oil on the detent path on the tang, not on the ball itself. Detent strength depends on lock bar tension, so a detent that changed after service points back to the bar, not the ball.

The stop pin. Clean its contact surfaces, look for wear, flats or a shifted position, and confirm the blade stops where it did before, open and closed. A worn or moved stop pin shows up as vertical play or as a change in lock engagement.

Then the check before the knife goes back in your pocket: the lock engages fully every time, releases without sticking, holds under moderate spine pressure, and lands on the tang where it did before you started. If any of those fail, work through the troubleshooting table before you touch the tension again. Owner disassembly doesn’t affect coverage, but damage done in the process does; see the warranty page.

Questions answered: Service and care FAQ.