Thread Star Knobs Clamping Knob Grip Stainless Knurled Thumb Handle Knobs Screws

Match knob diameter to the torque you need and the space available. The 42 mm knob suits confined spaces and lighter clamping loads (M5–M8). The 48 mm knob balances grip area and compactness for M10–M12 applications. The 70 mm knob delivers the highest hand-tightening torque and is best for heavy-duty fixtures or where maximum clamping force is needed without a wrench.

Measure the total thickness of the material being clamped, then add the engagement depth of your threaded hole or nut (typically 1–1.5× the thread diameter). For example, clamping a 20 mm fence rail into a 10 mm deep tapped M8 hole requires at least 30 mm of shank — order the 30 mm or 40 mm variant to allow full thread engagement with a small margin.

304 stainless steel provides tensile strength typically in the range of 515–620 MPa, which is adequate for hand-tightened clamping applications. These knobs are not rated for torque-wrench tightening or structural bolted joints. For heavy machining fixtures subject to vibration, consider adding a locking nut or thread-locking compound to prevent loosening.

304 stainless steel offers good resistance to atmospheric corrosion, fresh water, and mild chemicals. It is not fully immune to chloride-rich environments (e.g., coastal salt air or chlorinated water). For marine or highly corrosive settings, 316 stainless would be preferable. In typical workshop, outdoor enclosure, or food-processing environments, 304 performs reliably without surface treatment.

Yes. The threaded stud follows standard ISO metric coarse thread form, so it is compatible with any standard metric hex nut, flange nut, threaded insert, or tapped hole of the matching size (M5, M6, M8, M10, or M12). No special adapters are required. Always verify the thread pitch of your existing hardware matches the standard coarse pitch for the selected size.

Yes — these are a popular choice for 3D-printer bed-leveling knobs (typically M3–M5 range; select M5 here), CNC router fence stop blocks, and axis-limit adjustment screws. The knurled star grip allows precise, repeatable hand adjustment without tools, which is ideal for frequent calibration tasks. Confirm the thread size matches your printer or machine's existing hardware before ordering.

Order 1 piece for a single replacement or prototype test. Order 2 pieces for paired clamping points (e.g., both ends of a fence rail). Order 5 pieces for multi-point fixtures, production jigs, or to keep spares on hand — the 5-piece pack offers the best per-unit value. All pack sizes ship the same knob; only the quantity and price differ.