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The purpose of this paper is to present novel modifications to a RepRap design that increase RepRap capabilities well beyond just fused filament fabrication. Open-source RepRap 3-D printers have made distributed manufacturing and prototyping an affordable reality.

The design is a significantly modified derivative of the Rostock delta-style RepRap 3-D printer. Modifications were made that permit easy and rapid repurposing of the platform for milling, paste extrusion and several other applications. All of the designs are open-source and freely available.

In addition to producing fused filament parts, the platform successfully produced milled printed circuit boards, milled plastic objects, objects made with paste extrudates, such as silicone, food stuffs and ceramics, pen plotted works and cut vinyl products. The multi-purpose tool saved 90-97 per cent of the capital costs of functionally equivalent dedicated tools.

While the platform was used primarily for production of hobby and consumer goods, research implications are significant, as the tool is so versatile and the fact that the designs are open-source and eminently available for modification for more purpose-specific applications.

The platform vastly broadens capabilities of a RepRap machine at an extraordinarily low price, expanding the potential for distributed manufacturing and prototyping of items that heretofore required large financial investments.

The unique combination of relatively simple modifications to an existing platform has produced a machine having capabilities far exceeding that of any single commercial product. The platform provides users the ability to work with a wide variety of materials and fabrication methods at a price of less than $1,000, provided users are willing to build the machine themselves.

A low‐cost, open source, self‐replicating rapid prototyper (RepRap) has been developed, which greatly expands the potential user base of rapid prototypers. The operating cost of the RepRap can be further reduced using waste polymers as feedstock. Centralized recycling of polymers is often uneconomic and energy intensive due to transportation embodied energy. The purpose of this paper is to provide a proof of concept for high‐value recycling of waste polymers at distributed creation sites.

Previous designs of waste plastic extruders (also known as RecycleBots) were evaluated using a weighted evaluation matrix. An updated design was completed and the description and analysis of the design is presented including component summary, testing procedures, a basic life cycle analysis and extrusion results. The filament was tested for consistency of density and diameter while quantifying electricity consumption.

Filament was successfully extruded at an average rate of 90 mm/min and used to print parts. The filament averaged 2.805 mm diameter with 87 per cent of samples between 2.540 mm and 3.081 mm. The average mass was 0.564 g/100 mm length. Energy use was 0.06 kWh/m.

The success of the RecycleBot further reduces RepRap operating costs, which enables distributed in‐home, value added, plastic recycling. This has implications for municipal waste management programs, as in‐home recycling could reduce cost and greenhouse gas emissions associated with waste collection and transportation, as well as the environmental impact of manufacturing custom plastic parts.

This paper reports on the first technical evaluation of a feedstock filament for the RepRap from waste plastic material made in a distributed recycling device.

Isolated communities face a variety of inconveniences including severe remoteness, poor roads and extreme climate conditions, resulting in the lack of security of supply chains and exorbitant prices for cargo delivery. This paper aims to investigate the present advantages and prospects of applying 3-D printing to improve economics and everyday life of remote communities, reindeer herder case taken as an example.

This study covers the use of a low-cost open-source 3-D printer (RepRap) capable of fused filament fabrication to reduce operating costs for nomadic reindeer herder groups. Three case studies are provided for reindeer-specific applications to probe economic and technical viability of the technology, namely, ear-tags, electric fence components and lasso accessories.

3-D printed objects feature technical characteristics similar to those of analogues available on the market while reducing the price by 63 per cent. Distributed 3-D printing reduces the cost of raw materials by 68 per cent and shipping costs by 50 because of lower trip frequency. If all reindeer herders globally were to adopt distributed manufacturing of the three aforementioned sample items only, their annual savings from such solution would amount to US$2m. The paper discovers other economic, entrepreneurial, technical and environmental opportunities offered by 3-D printing put to service the needs of remote communities.

As the paper is the first-ever study of 3-D printing potential applied to the reindeer husbandry case, it is based on a more thorough analysis of the techno-economic feasibility of the technology, while cultural and entrepreneurial factors have been discussed as preconditions only.

The paper might serve as a valuable source of information for entrepreneurs, as well as for students and academics for further case studies in this area.

In remote conditions, 3-D printing offers a more sustainable way of good manufacturing. Numerous open source designs already available for specialists, financial effectiveness, environmental benefits and vast opportunities for entrepreneurs are among the most promising advantages of the technology.

The purposes of this paper are to study how entry-level 3D printers are currently being used in several shared machine shops (FabLabs, hackerspaces, etc.) and to examine the ambivalent emancipation often offered by 3D printing, when users prefer the fascinated passivity of replicating rather than the action of repairing. Based on a field study and on a large online survey, this paper offers to examine different practices with entry-level 3D printers, observed in several shared machine shops (FabLabs, hackerspaces, etc.). The recent evolution of additive manufacturing and the shift from high-end additive technologies to consumer’s entry-level 3D printing is taken as an entry point. Indeed, digital fabrication has recently received extensive media coverage and the maker movement has become a trendy subject for numerous influential publications. In the makerspaces that were taken for this field survey, 3D printers were very often used for demonstration, provoking fascination and encouraging a passive attitude.

As part of the work for a PhD research on personal digital fabrication as practiced in FabLabs, hackerspaces and makerspaces, since 2012, a large-scale field survey at the heart of these workshops was carried out. Particular attention has been paid to the relationships established between the inhabitants of these places and their machines, observing the logic of developing projects and the reactions or techniques used to counter unforeseen obstacles – that shall be demonstrated to be an essential occurrence for these moments of production. From Paris to Amsterdam, Barcelona, Rome, Lyngen (Norway), San Francisco, New York, Boston, Tokyo, Kamakura (Japan) to Dakar, a means of observing at the heart of more than 30 makerspaces (FabLabs, hackerspaces) has been created, with the aim of looking beyond the speeches relayed by the media and to constitute an observatory of these places. The field observations are confirmed by a quantitative study, based on a survey submitted online to 170 users, coming from 30 different makerspaces in more than ten countries in the world and reached through social networks or mailing lists. This survey offers a rigorous insight on the uses of 3D printing and leads to the consideration of the types of attention applied to 3D printing and the part played by the “default” or “trivial” productions used for their demonstrations or performances.

Based on both the observations and the quantitative survey, it can be discussed how the question of so-called “user-friendliness” is challenged by practices of repairing, fixing and adjusting, more than that of replicating. Indeed, it is claimed that this offers a possible meaning for 3D printing practices. In the description and analysis of the behaviours with 3D printers, this leads to privilege the idea of “disengaging” and the notion of “acting” rather than simply passively using.

3D printing is just one of the many options in the wide range available for personal digital fabrication. As a part of the same arsenal as laser cutters or numerical milling machines, 3D printing shares with these machines the possibility of creating objects from designs or models produced by a computer. These machines execute the instructions of operators whose practices – or behaviours – have yet to be qualified. These emerging technical situations pose a series of questions: who are those who use these 3D printers? What are they printing? What are the techniques, the gestures or the rituals imposed or offered by these machines?

Additive manufacturing or “3D printing” is a rapidly expanding sector and is moving from a prototyping service to a manufacturing service in its own right. With a significant increase in sales, fused deposition modelling (FDM) printers are now the most prevalent 3D printer on the market. The increase in commercial manufacturing necessitates an improved understanding of how to optimise the FDM printing process for various product mechanical properties. This paper aims to identify optimum print parameters for the FDM process to achieve maximum tensile strength through a review of recent studies in this field.

The effect of the governing printing parameters on the tensile strength of printed samples will be considered, including material selection, print orientation, raster angle, air gap and layer height.

The key findings include material recommendations, such as the use of emerging print materials like polyether-ether-ketone (PEEK), to produce samples with tensile strength over 200 per cent that of conventional materials such as acrylonitrile butadiene styrene (ABS). Amongst other parameters, it is shown that printing in the “upright” orientation should be avoided (samples can be up to 50 per cent weaker in this orientation) and air gap and raster width should be concurrently optimised to ensure good “inter-raster” bonding. The optimal choice of raster angle depends on print material; in ABS for example, selecting a 0° raster angle over a 90° angle can increase tensile strength by up to 100 per cent.

The paper conclusions provide researchers and practitioners with an up-to-date, single point reference, highlighting a series of robust recommendations to optimise the tensile strength of FDM-printed samples. Improving the mechanical performance of FDM-printed samples will support the continued growth of this technology as a viable production technique.

This work aims to present the design of a new continuous tool-path strategy for open-source low-cost fused deposition modeling (FDM) machines, such as Fab@Home or RepRap; and the development of an innovative integrated tool to design and fabricate customized tracheal stents with any FDM machine and six patient parameters. Both contributions were validated and implemented by obtaining a customized medical-grade silicone tracheal stent.

For the design of the new deposition strategy, a Python programming language was used. The new tool-path strategy was proposed as a continuous path to avoid drops and gaps and to improve the accuracy of the final model. Meanwhile, patient parameters were obtained by medical doctors and introduced into the innovative integrated system. On the one hand, one mold generated automatically, and viewed with Matlab® software, was fabricated with a Fab@Home machine, optimized with the continuous tool-path strategy. On the other hand, the same generated mold was viewed in SolidWorks/Excel software and was fabricated using a commercial FDM machine. Finally, the mold was filled with medical grade silicone, and a silicone tracheal stent was obtained.

Path planning for extrusion technologies is still a major concern, especially for open-source FDM machines. The results obtained in this work show the benefits of applying the newly developed continuous tool-path strategy to optimize the performance and efficiency of these machines. In addition, the proposed innovative integrated system allows the fabrication of customized tracheal stents rapidly and affordably.

The possibility of obtaining customized tracheal stents is a worthy challenge. Medical doctors could play a more active role and interact during the design process, helping to obtain more suitable stents. The method proposed herein would provide the opportunity to obtain real values from the trachea of a patient in the operating room and quickly fabricate a customized stent that would fit the patient's trachea perfectly.

The results obtained in this work are relevant and have future applications in both the medical and the additive manufacturing fields. The optimized tool-path strategy can help to improve and enhance the use of low-cost FDM machines. Moreover, the innovative automatic design approach to fabricate tracheal stents may open new market opportunities in the medical device field.