MAKING THE TRANSITION FROM CONVENTIONAL
tO ADDITIVE MANUFACTURING
Manufacturing sewing machine components more quickly and easily
They may sound like an unlikely pairing, but additive manufacturing and the sewing machine industry fit together like a glove. Gerhard Rempfer, a provider of sewing technology services, has been a qualified sewing machine engineer and sewing technician for 49 years. In that time, sewing machines have changed enormously. But one thing that's stayed the same is how laborious and time-consuming it is to manufacture binders.
THE STARTING POINT:
LABORIOUS AND TIME-CONSUMING MANUFACTURING PROCESS
Binders are conventionally made from stainless steel sheets by means of cold working (bending) and hard soldering before being reworked using machining techniques. The drawbacks of this process include fluctuations in quality and long delivery times. Binders are heavy, require a lot of material and are made from several components. Then Gerhard Rempfer had an idea. Why not make the components using additive manufacturing? This is where AMbitious came in.
MANY DIFFERENT MANUFACTURERS AND MACHINE MODELS
The components had to be redesigned from scratch so they could be tailored to the requirements of additive manufacturing and further processing – all in the aim of making them easier and quicker to produce. The biggest challenge was the huge number of sewing machine manufacturers and machine models available, which require different fastening shapes. The components had to be adapted to a range of tape materials, filling materials and attachments. Titanium was the metal chosen for the powder bed (L-PBF process). Dimensional accuracy was crucial during the manufacturing process to ensure a high level of repeatability. The behaviour of the tape, the surface finish and the universal area of application all had to be taken into account. It was also important to ensure that the components could be delivered quickly to keep production seamless. The conventional copper tubes, through which compressed air is shot onto the tape and which have to be adjusted by hand, were also replaced by air ducts integrated into the component. This has improved performance because the outlets are now located in a place where it was previously impossible to position them. This means that the compressed air is delivered exactly where it is needed.
MAKING THE TRANSITION FROM CONVENTIONAL TO ADDITIVE MANUFACTURING
toolcraft's experience in additive manufacturing, knowledge of materials and capabilities in further machining came to the fore when redesigning the binder. The component was redeveloped in close cooperation with Gerhard Rempfer. It has a longer service life, weighs less and can be produced to a consistently high quality. The assemblies and the way in which the entire component can be handled were simplified. The new design was created in Siemens NX using free-surface modelling and has parametric free surfaces. The software provides data consistency from the design stage through to simulation and manufacturing. This means that if the size of the component changes, the build job can simply be adjusted at the push of a button. The elimination of interfaces means there is no loss of data and no additional effort is needed to create the build job. To date, approximately 30 different components have been designed, printed and put to use in this way. AMbitious has advised Gerhard on materials and further processing steps and supports him with sales, communication with machine manufacturers and the development of a “standard workpiece”. Ultimately, producing binders using additive manufacturing is faster, easier and more cost-effective than conventional manufacturing. And since the number of skilled workers available to manufacture binders conventionally is declining, additive manufacturing is helping to ensure the sewing machine industry's future prosperity.
Here are some impressions!
Additively manufactured sewing machine components