Oldtimer Parts 3D Metal Printing - From Bumper to Hinges
There are often limits in the automotive aftermarket. There are boundaries between old and modern technology. But hardly any other modern technology is as predestined for use in the restoration of historical cultural assets as 3D printing.
New spare parts are no longer available? No problem! Reproduced alternatives only available in poor quality? No problem! Broken today and required tomorrow? No problem! No model available? No problem! "Using 3D printing or the so-called SLM (Selective Laser Melting) powder-bed process, there is now a solution for numerous applications available that has not been available to date, or only at disproportionately high prices," explains Roman Lengsdorf, department head for additive manufacturing at JP3D-Tec-Vision GmbH.
The company emerged last year from JP Industrieanlagen GmbH, a medium-sized mechanical engineering company with a focus on special mechanical engineering, automation and robotics. At some point its founder Johann Paulus wondered: "What will the future hold for metalworking" and immediately came up with the right answer: “increasing use of additive manufacturing." Thanks to the 3D printing technology, Paulus is opening up new business areas or supplementing existing processes and services. The big advantage for customers: With the support of a "decent" mechanical engineering company, JP3D-Tec-Vision can offer services that other (metal) 3D printing providers cannot offer.
Because printing or melting alone is not enough in most cases. This requires a precisely planned surface, precisely set bores and other components need to be machined to fit accurately. No matter what: The company can offer any classic metalworking task from a single source. Even work such as blasting, chrome plating and other surface treatments can be carried out at the Straubing-based plant - thanks to good connections to the relevant service providers. All of this is done without detours for the customer.
3D printing basically comprises different procedures for creating a required spare part. The easiest way is to use the corresponding "print data". There are more and more cases in which some member of a classic car club has already reprinted exactly this part. "At present, there are various databases on the Internet that provide corresponding files free of charge or for a fee," reports Markus Grünner, responsible for design, technology and production at JP 3D-TecVision.
If the customer does not have the corresponding data, he nevertheless has a sample that Grünner can scan. The Bavarian company uses a corresponding 3D scanner from Zeiss for this purpose. It takes a "snap shot" of the component on a rotary plate from different perspectives - with a precision of 7 µm. The result is a three-dimensional grid structure, which is then reworked on the PC - especially if the sample is damaged or an "improvement" is to be added to the reproduced workpiece. The reverse engineering process can also be used to create corresponding print data from CAD data, for example.
Spare Parts Produced in Original Quality
Once the mechanical engineering experts have compiled all the data they need, it's time for printing. Technologies that have been state of the art for plastics can be successfully used for metals and plastics with the help of the SLM process. In the case of metals, the starting material is melted and then blown onto the printing table or the workpiece. In the SLM process - also known as laser melting - the starting material is metal powder. A kind of rake pushes the powder over the "printing table". A laser immediately melts it into a solid structure of to the desired shape. In the next step, the printing table is lowered a bit, the rake moves some powder above to the resulting component, the laser melts the next layer and the process is repeated.
The great advantage of additive manufacturing is that components can be produced when conventional processes fail. In this way, cavities can be "imprinted" which cannot be created at all with presses or casting processes. Even a hinge that usually consists of several parts can be printed in a single operation. Thanks to the calculated play between pins and hinge halves, it moves perfectly afterwards. Even mechanically highly stressed components such as gear wheels can be printed using the SLM process - but in this case, too, subsequent fine machining (grinding) is required.
Lengsdorf considers the 3D printing principle as an ideal solution for the required number of units. While most classical production processes can only be realized with a certain quantity (in terms of price), additive production already pays off at a batch size of 1. "Cost advantages only arise, if several identical components can be produced in a single operation," says Lengsdorf. A further advantage: Once the print data is available, the finished component is ready in a few hours. A blink of the eye compared to the time it takes to produce something by means of classical mold making.
Costs Will Continue to Fall
In adaptive processes, the only limits are usually set by the component size, or rather the size of the working area of the respective "printer". The latest SLM printer from JP3D-Tec-Vision has a footprint of 280 x 280 x 365 millimeters. Accordingly, the diagonal width is slightly larger in terms of length. Another constraint: The main brake cylinder could be produced in the printer, but ... The Bavarian company don’t reprint safety-relevant components. This is another aspect that both the client and the contractor should take into account when it comes to remanufacturing: Copying trademark emblems, lettering and other protected materials can sometimes cause problems.
Oldtimer parts can also be reprinted in all kinds of materials and metals: whether headlight reflector, instrument ring or cover strips for the hood. The Straubing-based company is most frequently asked for components made of aluminum and stainless steel. But other metals are also possible. JP3D-Tec-Vision has even recently been able to process carbon using the FDM process, i.e. produce components made of it. No problem either: the transparent cover cap of a plastic interior light.
The strides taken by new technologies in the early stages are great. 3D printing is no exception. Roman Lengsdorf is convinced that not only the prices for 3D printers will (continue to) fall, but the operating costs of the machines and thus the costs for printed components will also continue to decline. Time is money, i.e. the shorter the process times, the lower the unit costs at the end of the day.
This article was first published by KFZ-Betrieb.
Original: Steffen Dominsky / Translation: Alexander Stark