🔘 #6-32 UNC Aluminium Knurled Thumb Screws – Anodised Hand Grip Knob Bolts (5–30mm Thread Lengths)
You’re working on a piece of machinery, a precision mould, or a bearing assembly – and you need a thumbscrew that’s easy to grip by hand and won’t rust or strip. These #6-32 UNC knurled thumb screws are machined from 6061 aluminium with a durable anodised finish. The diamond knurled head gives you a secure, non‑slip grip for tool‑less tightening and loosening. Fully threaded, with stud lengths from 5mm to 30mm (measured under the head). Lightweight, corrosion‑resistant, and available in a variety of anodised colours. Perfect for machine clamps, jig fixtures, and any application where a reliable, hand‑operated fastener is required.
✨ Key Features – #6-32 UNC Aluminium Thumb Screws
- 🔘 Knurled round head – Fine diamond knurling provides excellent fingertip grip – no tools required.
- 🎨 Anodised aluminium finish – Corrosion‑resistant, durable, and available in multiple colours (contact us for options).
- ⚖️ Lightweight 6061 aluminium – About 1/3 the weight of steel. Non‑magnetic and thermally conductive.
- 🛡️ #6-32 UNC thread (32 TPI) – Standard US coarse thread, widely used in machinery, electronics, and DIY.
- 📏 Thread lengths 5–30mm (under head) – Fully threaded for maximum grip in tapped holes or with nuts. Tolerance ±0.3mm.
- ✨ High quality workmanship – Smooth, burr‑free surface, even threads, and uniform force – no slipping or stripping.
- 🔧 Versatile applications – Machinery, precision moulds, bearing assembly, jigs, fixtures, and industrial equipment.
📏 Specifications – #6-32 UNC Aluminium Knurled Thumb Screws
| Thread Size |
Thread Pitch (TPI) |
Head Style |
Head Diameter (approx.) |
Head Height (approx.) |
Thread Lengths (mm, under head) * |
Material / Finish |
| #6-32 UNC |
32 |
Round knurled |
~8‑10 mm |
~5‑6 mm |
5, 5.5, 6, 10, 12, 16, 20, 30 |
6061 aluminium / Anodised |
* Length measured from underside of head to tip. Fully threaded. Tolerance ±0.3 mm. Colour options available – contact us for specific anodised colours.
🛠️ Where to Use #6-32 UNC Thumb Screws
| Application |
Typical Use |
| Machinery & equipment |
Tool‑less adjustment clamps, access panels, fixture stops |
| Precision moulds |
Quick‑release fasteners, alignment pins, handle knobs |
| Bearing assembly & jigs |
Adjustable stops, workholding clamps, assembly fixtures |
| DIY & hobby |
3D printer bed leveling, camera rigs, model making |
❓ Frequently Asked Questions – #6-32 Aluminium Thumb Screws
1. How do I measure the length of a #6-32 thumb screw?
The length is measured from the underside of the head (where the knurling meets the shaft) to the tip of the threaded stud. The head itself is NOT included. For example, a “#6-32 x 10mm” screw has a 10mm long threaded shaft under the head. All our lengths follow this standard.
2. Are these screws fully threaded? What about the 30mm length?
Yes – all #6-32 screws in this range (5–30mm) are fully threaded from under the head to the tip, giving you maximum grip in tapped holes or when using a nut.
3. Will the anodised finish wear off? Can I get different colours?
Anodising is a durable electrochemical finish that bonds to the aluminium – it resists scratches and fading far better than paint. Standard colour is natural silver. Other colours (black, red, blue, gold, etc.) are available on request – contact us for custom anodising.
4. Will aluminium thumb screws rust? Can I use them outdoors?
Aluminium naturally forms a protective oxide layer, and anodising adds extra corrosion resistance. They are suitable for indoor and light outdoor use. For continuous saltwater or harsh chemical environments, we recommend stainless steel thumb screws.
5. Do I need a nut or washer with these thumb screws?
If your equipment has a pre‑tapped #6-32 UNC hole, no nut is needed. For plain holes, use a standard #6-32 UNC hex nut. A flat washer is optional for load distribution.
6. What is the difference between #6-32 and M3.5? Can I interchange them?
#6-32 UNC is an imperial thread (0.138″ diameter, 32 TPI), while M3.5 is metric (3.5mm diameter, 0.6mm pitch). They are not interchangeable. Always match the thread type to your equipment.
