A Complete Guide To Pozi Pan Head Machine Screws

In our previous blog post, Your complete guide to machine screws, we discussed machine screws in general and spoke about the different types available.

Following on from that, in this post we will delve deeper into DIN 7985z Pozi pan head machine screws and explain their unique features, advantages and disadvantages etc.

By the end, you will have a better understanding of these commonly used machine screws.

What Are Pozi Pan Head Machine Screws?

Or what is a Pozi pan head machine screw? A Pozi pan head machine screw is a pan head machine screw, specifically with a Pozi type drive.

Pan head machine screws feature a unique large circular head and get their name because they resemble an upside-down frying pan.

DIN 7985 specifies pan head machine screws, and manufacturers precision-engineer the Pozi variant to DIN 7985z, where the “z” indicates the Pozi drive. These screws are most commonly available in sizes from M1.6 to M6, but you can also find them, though less commonly, in M8 and M10 sizes.

What Are The Different Names For Pozi Pan Head Machine Screws?

Depending on who you talk to, there can be many different names for these screws. Some of the most common being dome head pozi screws, round head screws and raised cheese head.

Sometimes people refer to the Pozi drive as cross-recessed or a cross head.

Some may call it Pozi drive and when combined with a pan head, name it a Pozi drive pan head screw or even simply a pan head bolt.

The correct name for the drive is Pozidriv, but most people commonly shorten it to Pozi.

What Are Pozi Pan Head Machine Screws Used For?

Pozi Pan Head Screws serve as great all-purpose screws. They are widely used in many applications, including machine and electronics assembly, and manufacturing.

The flat underside of the head is ideal to provide a large area of contact on the mating surfaces. However, looking at the top of the head. Pan head screws with their rounded profile and no jaggy edges provide a sleek finish with reduced worry of snagging.

What Are Pozi Drive Pan Head Machine Screws Made Of?

Now that you know what cross head / Pozidriv pan head screws are and their uses,. Let’s discuss what materials they are made from.

You can find these screws readily available in many materials from zinc plated steel, black zinc plated steel, A2 Stainless Steel, A4 Stainless steel and nylon.

Do Pozi Drive Pan Head Machine Screws Need Nuts?

If you are screwing Pan head Pozi screws into a pre-threaded hole then you do not need any nuts.

If however, you are fixing two parts together by inserting the screw through pre-drilled unthreaded holes. Then you will need a nut or a nut and washer to tighten the screw.

What nut you use will depend on preference or if there are special requirements like high vibration of the mating parts.

Common choices you may look at are the standard everyday hex full nut or hex half nut. Or if you need to factor in vibration and the fact they may work loose, a nyloc nut may be your best choice.

Are Pozi Pan Machine Screws A Good Choice?

If you need to fasten the screw tightly and not worry about any slippage of the driver, Pozidrive pan head screws are one of the best drives.

Let’s look at Phillips drive vs Pozi drive pan head machine screws. The Pozi drive has extra nibs in the drive socket, these provide more grip and also prevent the cam out that the Phillips are prone to.

Now let’s compare the Pozi drive to slotted pan head machine screws. The Pozi will always outperform the slotted for grip when driving. Slotted screws are best used for applications where not a lot of torque is required.

However, if you need to apply a lot of torque to the screws when tightening something in place. Then it may be a good option to go for a Torx drive pan head machine screw instead. When it comes to Torx drive vs Pozi drive machine screws, Torx will win every time due to its specially designed drive.

Can You Use Pozi Pan Head Machine Screws In Wood?

The design of machine screws does not suit screwing directly into wood, making them a poor choice for this purpose. To screw directly into wood, you would need to use wood screws.

However, if you need to frequently assemble and disassemble two parts, you could use a Pozidrive machine screw, nut, and washers for this purpose.

What Are The Similar Head Types To A Pozi Drive Pan Head Machine Screw?

People can sometimes confuse a couple of head types with a pan head machine screw. What are they and what are the differences?

First, we will discuss the difference between a Pozi round head and a Pozi pan head. The Pozi round head is more rounded than the pan head, almost like a half sphere.

There is also a socket button head. A socket button head shape is similar to the shape of a round head screw and does not include the straight sides that the pan head has. The socket button head also takes an Allen key instead of the Pozi drive.

What Sizes Do Pozi Pan Head Screws Come In?

As I mentioned above the most common sizes you will find are between M1.6 – M6. You might sometimes find them in M8 and M10 sizes, but these are not as commonly used

The available lengths vary and get longer as the thread diameter increases.

Listed below are some of the more common sizes of DIN 7985 z, Pozi drive pan head screws.

How Do You Measure A Pan Head Machine Screw?

You measure the length of a pan head machine screw from under the head to the end of the thread.

If you want to gain a better understanding of measuring screws, We have created a full dedicated blog post on how to measure a screw or a bolt.

Where Can I Find A Pozi Pan Head Machine Screw Dimensions Chart?

Are you looking for a DIN 7985 dimension chart?  

You will find one detailing the various dimensions for these screws by clicking on A2 stainless steel Pozi pan head or black zinc plated Pozi pan head machine screws. These links will take you to the product pages that have the dimensions on them.

Conclusion

DIN7985z Pozi pan head machine screws are a good choice where you need a screw that has a good drive that can be confidently driven with less risk of slippage than other drives.

These versatile screws can be used for many different applications across various industries.

They are available in many different materials for different applications and environments. You should consider which material to use to avoid any problems.

Would you like to explore other types of machine screws? View our other blog post, Your Complete Guide To Machine Screws. In this post, you can read about the various types available and click through to a more in-depth post on each type.

I hope this post was helpful.

If you still have questions that were not answered here Email us on sales@boltbase.co.uk or call us on 01259 218830. We are always happy to answer any questions that you might have.