Convertible tops: different types and processing

The word cabriolet, which is another word for a convertible, comes from French and can be translated as ‘to do a capriole or leap’. This is a fitting meaning because what is better in the summertime than driving 'with the top down’? Driving a convertible is a symbol of boundless freedom and sunshine. 

Soft tops and hard tops

There are different types of convertible tops. The two main categories are soft tops and hard tops.

convertible_tops-fabric-sewing_threadThe soft top is a cover made of a flexible, soft material. While the tops were once made of an upper layer of PVC material and a lower layer of backing fabric, today they are mainly made of composite textiles. The classic is a three-layer material consisting of fabric at the top and bottom and a rubber lining in the middle, which makes the fabric waterproof. People often mention fabric tops. The upper layer, which therefore faces outside, is usually made of a closely woven polyacrylic material, and the inner layer usually consists of a polyester fabric. It is therefore very important to use the right sewing threads as well as top fabrics when making convertible tops.

A&E Gütermann sewing threads for convertible hard topsA hard top is a firm but removable roof. This folding construction is usually made of steel, aluminium or fibreglass-reinforced plastic, and is primarily used in convertibles as a removable additional roof. When necessary, e.g. in winter, it can be mounted on the vehicle and stored when not in use. There are also hard tops that can be lowered into the boot. 

The demand placed on a soft top fabric in terms of the length of its lifetime is immense. This is because when the top is closed, it is fully exposed to the weather. In terms of lightfastness and UV resistance, weather resistance and stability of form, the soft top material must offer high performance. But it must also be resistant to damage during folding or when it is folded in. High stability against mechanical stress and high resistance to friction and abrasion are therefore also important.

However, the best material is useless when the workmanship is not also of high quality. In particular, the seams must withstand specific impacts. If the seams are not welded but traditionally sewn, the puncture holes must be sealed. This is achieved by 'taping’ the seams afterwards. The quality of the sewing thread plays a very important role. The less dampness it absorbs, the better. Equally important are high strength and lightfastness, so that the threads do not become brittle or fragile nor fade under constant sunlight. The sewing threads also need to have water- and windproof properties as well as special requirements in terms of their surface quality and lightfastness. Last but not least, the thickness of the thread plays an important role in the design of the seams.
 

To satisfy the special requirements of the seams of convertible hoods, A&E Gütermann offers a range of specific product solutions which meet the key needs of the car industry in terms of light fastness and surface finish. The production of our automotive sewing threads and the quality of the materials we use comply with the strict regulations in force in Europe. Our production is DIN EN ISO 9001:2015 and IATF 16949:2016 certified. So our sewing threads are perfect for use in the car industry.

Our product solutions for convertible tops:
•    Calora 20
•    Calora 40
•    Solbond 20
•    Solbond 30

Do you have a special requirement or would you live to receive individual consulting about the technical specifications of our thread? Then please feel free to contact us. Together, we can find the right solution for you: contact@guetermann.com