To the average person in the street, tension springs are those coiled things that you may see in a broken chair or torn mattress.
They all look the same, from the smallest in a ballpoint to the largest in a sofa, but although they are similar in design, they are not the same. Compression and tensions springs are in fact vastly different because they do different jobs.
Tension springs are used in the manufacture of trampolines and may be found in garage doors among many other applications. When the spring is tight it is resting and you can see this by looking at a closed garage door. When you open the door the force produces the tension by expanding the spring which contracts when you close it. Hence a tension spring holds components together.
For the general public most springs look alike, such as the tension and compression springs. However, they are designed to perform much different tasks. Their similarities exist in the design. Both are made up of a coil spring that is devised for elasticity and strength, but that is where their likeness ends. The main difference is that tension springs are meant to hold two things together while compression springs are designed to keep components from coming together. While they work in opposition with each other, they are both necessary for different products.
In contrast, compressions springs are designed to keep components apart. The resting position of a compression spring is the exact opposite of its tension counterpart. It is at rest when extended. These springs are commonly used in many more applications. The can be found in a pogo stick, watch, mattress, compressor and electrical switch to name just a few. Virtually every industry you can think of uses compression springs in one form or another.
Materials used in the manufacture of springs
Both types of spring can be manufactured from a diverse range of materials and the type you purchase will depend very much on the springs’ intended application. Factors to consider include risk of rust, the environment temperature and stress the spring will endure.
The materials from which springs can be made include:
- Copper Alloy
- Cold drawn steel
- Stainless steel
- Cold rolled steel
- Various type of wire
- Titanium alloy
If you have a project requiring compression or tension springs, standard or bespoke, do contact our highly experienced sales staff. They will be happy to advise you on materials and the best match spring for your specific needs.
Reupholstering may seem like hard work but even amateurs can’t deny the sense of achievement they feel when it is accomplished. Serpentine springs in upholstery are an excellent choice for refurbishing modern, shallow framed chairs, sofas, chaise and footstools. The strong wire they are manufactured from is 2 dimensional and they are popular not only because they are relatively cheap, in comparison to other springs, but also because of their anti-sag properties. However, they are not suitable for deep framed furniture when coil springs should be used.
Modern chairs and sofas
Serpentines are referred to as no-sag springs by professional upholsterers and are used in most modern chairs and sofas today. They are laid from the front of the piece to the back on the seating area and from the top to the bottom for the back rest. The springs are tied together around 3.8 centimetres from where they are attached, from side to side. There is less tying involved than with coil springs so the job is not quite as boring.
Durability and Gauge
You can replace coils with serpentine springs provided you use the correct gauge and durability of spring. Serpentines are usually purchased in 304.8 centimetre sections and then you can cut them to size with wire cutters. 8 or in some cases, 9 gauge springs are most commonly used in seating whereas the softer 11 gauge serpentine springs are more suitable for the back supports of chairs and sofas.
Don’t break the “reupholstering rule”
Generally, when reupholstering, there is a rule to use the same springs in a piece of furniture as you removed from it. Whilst you can use different springs, breaking the reupholstering rule may result in the piece looking misshapen. This particularly applies when you try to use coil springs when serpentine springs were in the original piece. When taking the chair or sofa apart you should pay attention to the layout of the springs because if you don’t apply the same arrangement to the new ones, the aesthetic appearance may not be what you had hoped for.
If you are unsure as to which springs to use for your reupholstering project call us on +44 (0) 1484 401610 for more information. We will be happy to share our knowledge about serpentine springs in upholstery with you.
No matter the type of chairs – antique, contemporary, classic or modern, they will all have a skeleton frame of timber or metal and some form of shape or body usually created by the tautness of upholstery springs and webbing. These springs give furniture its memory and underlying shape; if they aren’t correct to begin with, anything upholstered or created on top of them won’t be either. As upholstery springs suppliers, we know a thing or two about furniture upholstery so here is some useful information.
Arranging springs and webbing is an art
If you are rebuilding furniture to re-create the way it was previously, especially in the case of antique furniture, the way you arrange the springs and webbing is more of an art than a science. Upholstering is also partly dependent on the finances and desires of your customer, as well as your own personal preferences.
Initially, around the 1800s, high end furniture was constructed by using a frame with webbing stretched tightly over it, then building a layer of coil or cone type springs across the top of the webbing. This procedure is still the industry gold standard today with some manufacturers even using zig zag or serpentine springs.
Materials used to repair and renovate antique chairs
Common types of webbing
The ideal is normally to keep the chair renovation as near to the original design and fabric as possible. Traditional jute webbing adheres to this rule of originality, but when renovating more modern furniture, some upholsterers will choose man-made webbing.
There are two types of webbing that may be used to support coil springs, nylon and jute. Consideration should be given when using jute as to the final environment of the piece of furniture. This is because jute will not withstand outside weather conditions, where it may quickly deteriorate. Nylon is normally thinner than jute and when first introduced to the upholstery market was cheaper, but these days this is not always the case.
The webbing would normally be attached to the end of the wooden frame using tacks or staples. However, with some of the more modern type, lower priced chairs and sofas with flimsier frames made from plywood, this method is more difficult to achieve as the plies of wood may split. In these cases, the webbing is brought around and stapled to the side rather than to the end of the plywood.
Common types of upholstery springs
Coil, or double cone springs (Bonnell type springs) are hour glass, cylindrical shaped, metal springs which may be clipped to, or sewn onto a webbing base. The process of tying the springs to each other in 8 different directions (an 8-way hand tie) gives them neatness, order and tension to create a stable, hard wearing seat able to spread a person’s weight evenly.
Tension Springs, sometimes known as Extension Springs, are tightly wound coil springs that are manufactured to operate with tension when attached at both ends to other components. If these adjoining components are moved or pulled apart, the spring uses force to bring them both together.
They are closely wound springs, and as such, each coil is tightly held against the adjoining coils. The initial tension of the spring determines how tightly coiled the springs are.
The majority of tension springs have end fixings of loops or hooks which attach to other components to create the tension. Siddall & Hilton supply many types and sizes of tension springs to suit a wide range of requirements.
Most upholsterers will use tension springs in seat and back applications. They are applied for use in many industry sectors, Rail, Agriculture, Oil and Gas, Food Processing and Aerospace. They are also used in manufacturing, general and car manufacture, used for trampolines, farm equipment, tools such as pliers, garage doors and even automotive parts. Tension springs have a multitude of uses.
When you look to confirm your requirement for these springs, you need to take into account the following details:
Free length – the length of the spring when unloaded
Extended length – the length of the spring when used at full capacity and extension
Spring rate – the force per unit deflection amount
Maximum load – the possible load when the tension spring is at full capacity and extension
Diameter of spring and wire – Also take into account the thickness of wire required and actual diameter of the spring
Siddall & Hilton supply Tension springs in natural and plastic coated finishes depending on your specific application.
Tension spring assemblies (spider units) can be supplied for all your needs and the most common end fixings are different types of end loops and hooks, but there are also others available, screw fixings, shackles etc.,
Not sure what you need?
Please contact us at Siddall & Hilton for more detailed information. Our friendly customer service personnel are highly trained and always willing to help customers with design to ensure they get the right spring for their application.
Apart from companies like ours, furniture manufacturers and upholsterers most people wouldn’t have a clue what Bonnell or double cone springs are but you might be surprised how much they feature in our everyday lives. These furniture and upholstery springs are often used by orthopaedic mattress manufacturers and in a wide range of high quality furniture products where firmness is required.
They are not just used in machine made furniture but by thousands of individual traditional upholsterers worldwide. High quality upholstery springs provide comfortable seating, and ease the back pain of sufferers allowing them to get a decent night’s sleep.
It’s not just new furniture that benefits from double cone or Bonnel springs. Antique dining chairs, chaise longue, couches and armchairs can be positively rejuvenated with them. A good professional upholsterer takes time and uses quality materials in restoring antique furniture back to its former glory. Re-upholstery can be expensive because of the time taken and the materials used. Here is a list of the main materials and tools a professional furniture restorer needs to carry out the work:
- Upholstery springs
- Spring twine
- Staples (usually half inch) and staple remover
- Jute webbing and a stretcher for it
- Upholstery tacks (usually 12 oz)
- Tack hammer (preferably magnetic)
- Fasteners (with Klinch-it tool)
- Air compressor with hose
- Button twine with specialist button needle
- A pair of goggles
Time consuming preparation
The preparation for restoration can take days with removing the fabric, old staples or tacks and padding and although it is possible to use the old upholstery springs it’s invariably better to use new. With constant use and new springs chairs can last more than a lifetime.
If the furniture is made of wood, upholsterers will either manually strip the old varnish/paint or send it away to be dipped in paint or varnish stripper. When it comes back there may be rubbing down to do, staining and re-varnishing. So you can see that it’s hard work.
Restoring a piece of antique furniture can often work out more expensive than buying new but many people prefer to pay the additional cost for something they may never be able to find a substitute for.
For more information about our range of tension, serpentine and upholstery springs call us or complete our web form. We are happy to share our knowledge with you free of charge and give a no obligation quotation.