Disassembly, reassembly and pivot tuning

A full teardown is due when a pivot flush no longer clears grit, when the action has gone gritty or uneven, or when the knife has seen salt water or a season of hard carry. This page walks the knife apart and back together and sets the pivot. It assumes you have the factory bits and a driver that takes them, non-magnetic tweezers, a tray and a light-colored mat, and that you have recorded the action, the centering, where the lock bar sits on the tang and how tight each screw feels; if not, start with Tools, supplies and preparation. Taking the knife apart does not void the warranty; damage done in the process is not covered. The policy is on the warranty page.

Disassembly

Work with the blade closed, the knife flat on the mat and the show side up. The screws are proprietary slotted hardware, so use the factory bit that fills the slot; the Q95 Ursus and F95 Ursus are the exception, taking hex bits, and Sinkevich collaborations carry their own “tri-lobe” screws.

1. Remove the pocket clip. Back the clip screws out with the bit that fits them and put them in their own spot in the tray.

2. Remove the scale screws in a cross pattern. Loosen each body screw a fraction of a turn, moving diagonally across the handle rather than along it, then take them out in the same order so the scale comes off without warping. Screws can differ in length, so lay each one down in the position it came from. If a screw resists, the factory thread locker is holding it: warm the screw head briefly with a small heat source, then try again. Never force it.

3. Lift the scale straight up. Raise the show-side scale vertically, slowly and level. If it does not want to come, look for a screw you missed; do not pry and do not tilt, because a tilted scale spills bearings.

4. Deal with what is under the scale. On SRBS the single row of balls sits in a race and, on the early loose-ball knives, rolls if the race tips. On MRBS you find several rows of loose 1.5 mm balls in machined races on each side, some staying in the scale and others on the tang. On SRRBS, the Custom Division and Sprint Run system, the single row of cylindrical rollers is loose and scatters, so photograph it before anything moves. On the double- and multi-row roller systems (DRRBS and MRRBS) of full customs and rare Custom Division pieces, stop here and read the workshop position on Bearings and locks by system.

5. Remove the blade. Lift it out of the frame, note the orientation of any washers or race inserts, photograph any shim before you move it, and set the blade aside where the edge can’t reach you.

6. Handle the lock bar side. The lock bar is under tension; control it as the blade comes out. Remove the lock bar stabilizer if the knife has one, photograph the position of any insert, and leave the lock bar geometry alone.

7. Remove the pivot only if you need to. Cleaning the races and the pivot barrel rarely requires it. If it comes out, use the bit that fits it and keep any shims or washers in order.

Before you clean anything, count the balls or rollers from each side against your photos and keep the two sides apart. Cleaning and lubrication by bearing system and by lock type is on Bearings and locks by system.

The mistakes that cause most damage

Tools. A bit that does not fill the slot, a driver that lets it cam out, or a hard twist on a screw still held by thread locker are how screw heads get chewed and threads stripped, and a torn screw is the damage the warranty names as yours. Magnetic tools pull balls out of position and magnetize them; keep magnets for the screw tray.

Process. Skipping the photos and baseline notes, prying scales apart, tilting a scale as it lifts, working on a dark or cluttered surface and rushing are how parts get lost and knives go back together wrong. Stop when something resists and find out why.

Bearings. Balls and rollers get lost when they are not contained, mixed between sides, handled with bare fingers, cleaned with the wrong solvent or stored in a heap. Each side goes back where it came from, in the arrangement you photographed.

Lock. Flexing the lock bar, scratching the lock face, disturbing an insert that did not need to move, and forcing or over-tightening the stabilizer all change how the lock engages, and titanium does not forgive repeated bending. Clean the faces; do not adjust anything you did not measure before you started.

Reassembly

Every part is clean and dry, laid out by side, and the lubricant for your bearing system is at hand: a light knife-pivot oil such as KPL or Nano-Oil 10wt for the ball systems, less oil on roller systems, where a lighter Nano-Oil 5wt is the usual choice.

1. Prepare the races. Check both scales’ races for lint, scoring and residue, then put a small amount of oil in each channel and spread it evenly.

2. Seat the bearings. SRBS: the full count of balls, evenly spaced in the race. MRBS: rebuild each row against your photo and oil each row lightly. SRRBS: seat every roller flat in its channel with non-magnetic tweezers, match the arrangement to the photo and use a single small drop across the row. A ball or roller sitting proud binds the moment the scale comes down.

3. Prepare the lock. Confirm the insert is secure where the knife has one, the detent ball is clean and seated, and the stabilizer is ready to go back in with a trace of blue 242 on its threads.

4. Set the blade. Lower it onto the lock-side bearings with the pivot hole lined up and nothing disturbed, then swing it through its arc to confirm it moves freely.

5. Fit the scale. Bring the show-side scale down level, line up every screw hole, and check that no ball or roller shifted as it seated.

6. Install the screws. Start the pivot finger-tight. Then run the body screws in by the same cross pattern you used to remove them, snug and even, without pulling any one of them down hard.

7. Test the action. Open and close the knife, feel for smoothness through the arc, and check that the lock engages and releases and the detent holds the blade closed. A rough or catching action means a bearing is out of place; open it again now rather than tuning around it.

8. Finish. Refit the clip, set the pivot as described below, apply thread locker once the setting is final, then check centering and compare the action with your notes.

Pivot tuning

Set the pivot after the body screws are at their final tension, never before, because the scales load the bearings. With the pivot finger-tight, tighten it until you feel the first resistance in the blade’s swing, then go about 1/8 turn further. Open and close the knife several times, then hold it open and push the blade gently from side to side.

From there, work in 1/16-turn steps. If the action is stiff, loosen 1/16 turn and test again. If the blade has side-to-side play, tighten 1/16 turn and test again. You are looking for the threshold where play just begins; the right setting sits a hair tighter than that point, with the action still free. Check the lock and the detent at every step, because pivot tension changes both. Then leave it: the action settles over the first few hundred cycles, and the final touch is best made after that.

The systems respond differently. SRBS tolerates a wide range of tension and can start a little tight. MRBS is more sensitive and rewards the small steps. On SRRBS, 1/16 turn is a large change, which is why roller pivots are best left at the factory setting.

Thread locker goes on last. Once the setting is final, back the pivot screw out, put a tiny amount of blue 242 on the male threads only, run it back to the same setting and leave the knife for 24 hours to cure. Blue 242 releases with the same bits later; do not use anything stronger.

Centering

If the blade sits off center when closed, loosen every body screw slightly and retighten them evenly in the cross pattern before you touch the pivot; uneven scale pressure is the usual cause. If it still favors one side, adjust the pivot in 1/16-turn steps while watching the gap, and check that the bearings on the tight side are all seated. Centering that drifts after reassembly points to a screw that has backed off or a race that was not fully seated; check the screws first. Anything the screws and the pivot don’t cure belongs in Troubleshooting after reassembly, together with play, grit, lock stick and detent problems.

Model notes

On the F3, which is a liner lock, control the lock bar as the blade comes out and confirm it travels freely before reassembly; the lock bar stabilizer, if the model carries one, goes back in before the scale. On the 111, whose liner lock carries a stainless insert (the inset lock), photograph the insert’s position before the scale lifts and confirm it has not shifted before the final tightening. On the Sinkevich Fat Strip, Fit Strip and Skinny Strip, which are liner locks, clear the lock bar channel and check that the liner travels freely before you close the knife up. On carbon fiber inlay models, seat the inlays fully and check for debris where the material meets titanium before the screws go in; a trapped speck holds the scale off and skews centering. Custom Division and full custom pivots, including the duck foot hardware on Sergey Shirogorov’s full customs, are best left at the workshop’s setting; when one needs work, the route is the factory or the dealer who sold the knife.

Questions answered: Service and care FAQ.