DIN 551 Slotted Grub Screws, Flat Point
We supply DIN 551 slotted flat point grub screws in steel and A2/A4 stainless steel from M1.6 to M12. Grub screws are headless screws driven fully below the surface; the flat point bears squarely on a mating face and is the general-purpose choice for locating collars, pulleys and fittings.
Also known as: grub screw, set screw, headless screw, slotted set screw, flat point grub screw, blind screw.
DIN 551 dimensions
| Diameter | Pitch | Point diameter | Slot width |
|---|---|---|---|
| M1.6 | 0.35mm | 0.8mm | 0.25mm |
| M2 | 0.4mm | 1.0mm | 0.25mm |
| M2.5 | 0.45mm | 1.5mm | 0.4mm |
| M3 | 0.5mm | 2.0mm | 0.4mm |
| M4 | 0.7mm | 2.5mm | 0.6mm |
| M5 | 0.8mm | 3.5mm | 0.8mm |
| M6 | 1.0mm | 4.0mm | 1.0mm |
| M8 | 1.25mm | 5.5mm | 1.2mm |
| M10 | 1.5mm | 7.0mm | 1.6mm |
| M12 | 1.75mm | 8.5mm | 2.0mm |
What is the difference between a grub screw and a set screw?
In UK trade language the two terms overlap: a grub screw is a headless screw driven fully into a tapped hole, and "set screw" is often used for the same thing, although in UK bolt terminology it can also mean a fully threaded hex screw. DIN 551 is the headless, slotted, flat point pattern.
Is DIN 551 still a current standard?
DIN 551 has been superseded by ISO 4766. The standards are closely related, although dimensional or technical differences may exist. If your drawing specifies DIN 551, send us the requirement and we can identify the appropriate product.
When should I use a flat point grub screw?
The flat point bears on the mating surface without digging in, so it suits parts that are adjusted or removed frequently, or where marking the shaft must be avoided. For a more positive lock, see cone point DIN 553 or cup point DIN 438.
Need DIN 551 in a non-standard size or material?
Send us your drawing — specials quoted within 24 hours.