RS PRO Pozidriv Pan Head A4 316 Stainless Steel Machine Screw, M4, 8mm

Metric Thread - A4 Stainless Steel

Machine screws are fully threaded screws that are specifically designed to be used in pre-tapped holes or used with conforming nuts and washers in through holes. Machine screws are available in an array of configurations, materials, driver head types and sizes. As their name implies, machine screws are used to fasten various components together in appliances, tools, machines, electronic devices, vehicles amongst a whole host of other objects. Machine screws are similar to a bolt but have a socket in the head which allows it to be turned with a screwdriver.

Are they easy to assemble?

Our pan head machine screws have been designed to give the user an easy assembling experience.

When are they used?

The pan head with cross recess screws are an excellent solution when you need to affix varied parts and components of machines together.

Features & Benefits

• Good corrosion resistance • Recyclable
• Non-magnetic

Pozidriv, sometimes shortened to Pozi, stands for “positive drive”. This head type has a cross recess in the centre with four small indentations around it creating 8 points of contact. This design provides improved engagement and contact with the screwdriver and prevents ejection force when tightening or loosening the machine screw.

Typical Applications

• Light engineering
• Domestic appliances
• Electronics

What are Machine Screws Used For?

Machine screws are designed to hold separate components together in a wide range of applications such as industrial machinery and vehicle engines. They are screwed through pre-drilled tapped holes in 2 components and can fastened at the rear with a nut. This marine grade 316 steel machine screw is ideal for use in the following:

• Swimming pools
• Chemical plants
• Boat deck fittings
• Dairy equipment
• Medical sterilising equipment
• Sewerage treatment plants

Frequently Asked Questions

What Does M2.5, M3, M3.5, M4, M5 Mean?

These measurements are found on metric screws, The 'M' stands for Metric. The number after the 'M' is the nominal outer diameter of the screw in mm.

How Do I Cut a Machine Screw?

Damage to the machine screw threads can prevent parts from fitting together properly, therefore care has to be taken when cutting them and the correct tools used.

Cutting a small machine screw (up to standard size #10 or metric size M5 (5mm)
Use a pair of multipurpose wire strippers or electricians pliers that feature M2.5, M3, M3.5, M4, M5 threaded holes. These holes are designed for cutting bolts without damaging the thread. Open the jaws and thread the machine screw into the correct size hole to the distance required. Squeeze the tool handles closed and the screw will be cut at the point where the two halves of the jaws come together. You will have a clean cut without any thread damage.

Cutting a large machine screw (larger than size #10 or metric size M5 (5mm)
This is best done using a hacksaw. Thread the nut on the screw until it reaches the desired point on the head side of the cutting line. Place the screw in a vice or clamp to keep it secure when cutting and cut the screw as straight as you can. When you unthread the nut it will repair and realign any threads that may have been damaged by the saw blade.

Note

This product equires a Pozidrive Screwdriver. We offer a range of pan head machine screws in various thread sizes and lengths. Refer to the datasheet and range overview download file for details.
If A4 (316) stainless steel is not what you are looking for, we can also offer you the fasteners in steel and brass. We also offer the cross recess machine screws in A2 (304) stainless steel, steel and nickel plated brass. Refer to the fasteners selection guide for details.

Standards

Threaded in accordance with DIN 7985