How to Choose the Best Metal Finish for Your Bike Storage: A Comprehensive Guide
We cater to the needs of many clients across the business and public sectors, and with so many years of experience, we have a good idea of what works best for our customers. This is why our bike storage products come in wide varieties with different sizes and designs.
To increase the flexibility of our bike shelters and racks even further and give our clients greater freedom regarding how the final product looks, we also offer several different metal finishes from which to choose. However, we have found that this sometimes leaves clients wondering – what is the best metal finish to select when the bike storage product of their choice comes in several variants? This is why we wrote this short guide to help people navigate each finish’s differences, benefits and limitations.
Types of metal finishes
Many industries depend on metal and metal production for parts and components. Our sector is no exception. A great variety of metal finishes are used out there, such as hot dipped galvanisation, electroplating, powder-coating, phosphate coating, electropolishing and many others. Some of these methods are used primarily for decorative purposes, like powder-coating for adding colour. In contrast, others are used to add further protection against the environment, like galvanisation for extra corrosion resistance. Learning about the different metal finishes allows you to choose the most appropriate one for your next project.
In this guide, we will focus only on the finishes we use. Depending on the product you are looking at, there may be several options. Let's take our 10 Space Bike Shelter as an example. The shelter is made from 50mm box tube steel to BS EN standards. We ship with no finish where you can apply your own, or you can select hot dipped galvanised, polyester powder coated to BS EN ISO 1461:1999 standard finish in any RAL code colour or both - galvanised and powder coated.
2. Galvanised Finish
Steel is an alloy of iron and carbon with small amounts of other elements. It is an excellent metal that can be fully recycled and re-made into new steel products. It has a long life, great strength and is low maintenance, making it the perfect material for bike shelters and street furniture. Steel is often galvanised for added benefits.
- What is a galvanised steel finish?
We recommend clients choose, as a minimum, the galvanised option as it gives the metal added strength and makes it more durable. Galvanising steel is a process in which the steel is exposed to zinc. There are several ways to do this: hot dip galvanising, electroplating, metallising, sherardising, mechanical plating, in-line galvanising, and zinc-rich paint. Each method has a different cost attached to it, resulting in different thicknesses of zinc layers.
We use hot dip galvanisation, done by submerging the metal in a bath of molten zinc. The zinc binds to the steel and forms a protective coating giving galvanised steel its signature splotches surface pattern. This is one of the most popular ways to galvanise steel as it is cost-effective and results in a thick and even layer of zinc forming. Another advantage of hot dip galvanising is that it covers areas which are usually weak spots for corrosion, like corners, recesses and seams, very well, giving them complete protection.
- Advantages of galvanised steel
Galvanised steel has a comparatively low initial cost when weighed against other treated steels. Products are less expensive to produce, can be used right after delivery, and no additional costs need to be incurred.
Due to its iron content, steel is prone to rusting. Galvanised steel also has excellent rust resistance due to the zinc coating, which acts as a protective barrier between the elements and the steel underneath. Adding this layer is essential for any street furniture, bike shelters or other products made from it that will spend significant time outdoors or in a humid environment.
The galvanisation strengthens the steel and makes it more durable. The hot dip process produces a metallurgically bonded coating, giving the steel superior resistance to damage. The protective layer is excellent at protecting even corners and recesses, which are infamously hard to shield from moisture and wear down with time. Galvanisation gives the metal an extended life expectancy with very little to no maintenance needed.
The zinc coating acts as a physical barrier but also gives something called sacrificial protection. This means that as the galvanised coating slowly corrodes over a long time, it will corrode preferentially. Even if there are scratches and small breaks on the surface, the zinc around will ''sacrifice'' itself and corrode first, thus protecting even the exposed steel. The mechanism is called sacrificial protection and is also why galvanised products typically don't require much repair work.
- Disadvantages of galvanised steel
Galvanised steel has very few disadvantages in its use in cycle shelters, bike stands, or bike racks. An extra cost is added on top, and this could start weighing on the budget for extensive projects, but the advantages and long-life properties usually outweigh the negatives.
3. Powder Coated Finish
Powder-coating is a dry finishing process that has become increasingly popular. Advancements in the industry have made it possible to have a truly great choice of colour. Furthermore, contemporary paints have excellent qualities that make them efficient in providing the right aesthetic and decorative value but also have given them excellent performance properties like durability and protection.
- What is powder coated finish?
On many of our products, we offer the option of applying powder coating to the metal in a RAL colour of your choice. Powder coating is a process where the metal is painted with a protective layer of polyester coating, giving it a colour of your choice and some extra environmental protection.
To correctly apply powder-coating to steel, the steel must first be cleaned from any grease, dirt or small bits that may interfere with the paint and not allow it to stick to the metal properly. The colour is then applied to the steel and the coloured product cures at a very high temperature. The heat makes the paint chemically react and bind to the metal creating high cross-link density. This makes the coating strong and resistant to breakdown.
- What are RAL colours?
The term RAL colour is a common one in the industry, but often it is an unfamiliar one for clients. RAL colours are the colour you can choose from when it comes to the powder-coated colour finish for your selected product.
RAL stands for ReichsAusschuss für Lieferbedingungen, and it was initially developed in Germany back in 1927. RAL is a colour matching and management system used in powder coating to ensure standard colours are applied across the board. It is similar to, for example, what Pantone is for the printing industry – a way of standardising colour, making it easy to communicate what shade you need, and consistently achieving the same result regardless of who and where is printing it for you.
- Advantages of a powder-coated finish
Powder-coating your selected bike shelter is the best way to get the exact look you need to fit your environment. The almost endless choice of RAL colours gives you great freedom and the option to have a beautifully finished product with the aesthetic you want.
Ordering a bike storage product that has been pre-coloured may look like an added cost initially, but it saves you any extra spending and hassle after delivery if you decide to paint it yourself.
Powder coating is also not just decorative; it is also an extra protective layer on top of the metal, giving some shielding from the elements and wear and tear.
- Disadvantages of a powder-coated finish
There is an extra cost associated with the added step of painting. As we mentioned, painting the metal does give it an extra coat of protection; however, the protective layer powder coating gives you isn't as strong as the zinc one, which forms as a result of galvanisation. And you need to keep in mind that once a product has been powder coated, it cannot be galvanised, as the paint will interfere with the chemical process.
Powder coating is a process that requires excellent attention to detail. Every step needs to be followed precisely to ensure the final product has no defects, which can easily occur if the manufacturer isn't careful. Different paints require different handling, but overall great attention must be paid to cleaning and removing contaminants when preparation is done. This is why you must choose a provider with experience and skill.
Additionally, some touch-up work may be required in time as pain may fade, get scratched and be damaged by impact.
3. Galvanised & Powder Coated Finish
As we already explained, galvanisation is the process of metallurgically binding zinc to steel, resulting in a more robust and corrosion-resistant metal. Adding powder coating to this is a great way to get the best of both worlds – the strength of the galvanised steel and the look of a colour of your choice.
- What does galvanised and powder-coated finish mean?
Knowing already what the benefits of galvanised steel are, we can explore the other option we often offer – galvanised plus powder-coated colour. This option gives you the benefit of retaining all the significant advantages of the galvanised metal with the addition of colour choice.
Galvanised steel, as you know, has that specific patterned look. However, this often differs from what designers, architects and building owners seek. They would like a bike shelter with a long life and a strong and durable construction but also one they can choose the colour and look of. This is where powder coating comes in.
Powder coating is a layer of colour applied after the galvanisation. This second step is done by applying an even layer of polyester powder coating to a recently galvanised product. This then cures in a stove at a very high temperature. All of this is usually done within a few hours of the galvanisation.
- Advantages of a galvanised and powder-coated finish
As said above, the apparent advantage is that you get all the durability, strength and corrosion resistance of galvanised steel, coupled with an aesthetically pleasing finish of a colour of your choice. This allows you to have components for your building match your exact specifications and gives you greater freedom when it comes to design.
There is also a further benefit to applying a polyester powder colour finish. The colour top coat effectively becomes an extra protective layer that shields the zinc, which in turn shields the steel. This cascading protection adds strength and durability to the metal, increases its life and decreases the need for maintenance even more.
- Disadvantages of a galvanised and powder-coated finish
Opting for the galvanised and powder-coated finish is a great choice that gives you both strength and design flexibility. However, there are a few disadvantages.
Painting adds extra initial costs, sometimes undesirable, depending on the budget.
As we mentioned in the above section about powder-coating, you must be very careful when selecting a provider as the work is done by a specialist and painting instructions must be followed precisely to avoid defects. Maintenance may be needed with time, as the paint may need a little touching up.
5. Stainless Steel
As we explained in our introduction, we are including stainless steel in our guide, even though it is a different steel alloy and not a metal finish. We would like to briefly explain the difference between stainless steel and galvanised steel, as we offer it as a choice for some of our bike racks.
- What is stainless steel?
Steel is an alloy of iron and carbon, which has improved resistance to fractures and strength. Stainless steel is a type of steel which also has the addition of at least 10.5% chromium. This element gives stainless steel its sleek look and superior resistance to corrosion and rusting. Stainless steel can be further modified to enhance specific properties of the steel by adding other elements, like nickel, manganese, molybdenum and others, in particular proportions. There are different grades of stainless steel.
- What are stainless steel grades?
Some of our products, like the Kirby Cycle stand, are offered in stainless or galvanised steel. Another detail is worth pointing out. In the description of our products, you may come across the words, "Stainless steel is grade 304 as standard".
- What does 304 stainless steel grade mean?
Stainless steel is divided into several types based on the metal's crystalline structure. The two popular grade series are the 200 and 300 series. Grades are there to give you an idea about what you can expect from a specific steel. They are like shortcodes for composition and properties. The 200 are chromium-manganese-nickel alloys, and the 300-grade series are chromium-nickel alloys. The most common grades of stainless steel used are 304 and 316. They are similar but also have an important distinction – 316-grade stainless steel is best applied underwater and in saline environments.
304-grade steel makes excellent products, so we use it as a standard for manufacturing cycle racks whenever we make them out of stainless steel. It is highly durable, and it has excellent corrosion and oxidation resistance. This steel does very well in harsh outdoor environments, can withstand high temperatures, and has high tensile strength. Additionally, it is relatively inexpensive to manufacture. As said above, the 316 grade has similar advantages but performs better against acids, alkalis and chloride and can be a bit more expensive.
- What are the differences between stainless steel and galvanised steel?
Galvanised steel is coated in a layer of zinc which protects the steel underneath from corroding. It has great rust resistance and strength. Stainless steel, on the other hand, as said above, is an alloy with added chromium. It is very strong and resistant to rust too.
Stainless steel overall corrodes less, even in marine environments, and is generally stronger. Galvanised steel offers excellent resistance against water and chlorine but wouldn't last long if submerged under or near the sea.
Both stainless steel and galvanised steel are strong and would resist wear and tear for long periods. However, stainless steel is generally stronger and lasts longer. Stainless steel usually has higher tensile strength, too. However, it is a little more specific to work with and needs specialist skills to handle.
Stainless steel is also more expensive, which is often a consideration when choosing between the two options.
Additionally, both steels have distinct looks – the spotted signature look of galvanised steel is a little more industrial, whilst the polished one of stainless steel is a bit more sleek and modern. If look is a consideration for you, this may play a role in deciding.
Overall, both make for strong, rust-free, long-life bike storage products like cycle stands or bike racks. Often the more budget-friendly galvanised steel option works just fine. However, if budget is not an issue, you can always choose the stainless steel option for extra added longevity.
We have extensive experience in providing bike storage solutions and are here to advise any client on what is best for their space, budget and aims. We would love to hear from you – whether it is feedback on this guide, advice on bike storage or placing an order. Don't hesitate to get in contact with us.