Slot die coating is growing in popularity because it is a low operational cost and easily scaled processing technique for depositing thin and uniform films rapidly, while minimizing material waste. The complex inner geometry of conventional slot dies require expensive machining that limits accessibility and experimentation. In order to overcome these issues this study follows an open hardware approach, which uses an open source 3-D printer to both fabricate the slot die and then to functionalize a 3-D slot die printing system. Polymer materials are tested and selected for compatibility with common solvents and used to fabricate a custom slot die head. This slot die is then integrated into a 3-D printer augmented with a syringe pump to form an additive manufacturing platform for thin film semiconductor devices. The full design of the slot die system is disclosed here using an open source license including software and operational protocols. This study demonstrates that functional lab-grade slot dies may be 3-D printed using low-cost open source hardware methods. A case study using NiO2 found an RMS value 0.486 nm, thickness of 17 to 49nm, and a maximum optical transmission of 99.1%, which shows this additive manufacturing approach to slot die depositions as well of fabrication is capable of producing viable layers of advanced electronic materials. Using this method, a cost savings of over 17,000% was obtained when compared to commercial slot die systems for laboratories.

There is an opportunity to radically reduce the costs of experimental research while improving it by supporting the development of free and open source hardware (FOSH) for science and engineering. By harnessing a scalable open source method, federal funding is spent just once for the development of scientific equipment and then a return on this investment is realized by direct digital replication of scientific devices for only the costs of materials. FOSH for science and engineering has been growing at a rapid pace and already supports many fields. Scaled peer production and digital replica-tion reduce traditional costs by 90–99 percent, making scientific equipment much more accessible not only for research but also for preparation of the next generation of scientists and engineers as research-grade tools are available for science, technology, engineering, and math (STEM) education. I propose four straightforward and negative-net-cost policies to support FOSH development and improve access to scientific tools in the United States. The policies will directly save millions in research and STEM education expenditures, while providing researchers and students access to better equipment, which will promote advances in technology and concomitant benefits for the US economy. Free and open source hardware can reduce research and education costs, increase access, and enhance scientific and technological progress.

RepRaps (self Replicating Rapid prototypers), which 3-D print objects using fused filament fabrication (FFF), have evolved rapidly since their open source introduction. These 3-D printers have primarily been limited to desktop sizes of volumes of ~8000 cm 3 , which has limited the attention of the scientific community to investigating deformation of common thermoplastics such as polylactic acid (PLA) used in FFF printing. The only existing physically relevant deformation model was expanded here to use a physics-based temperature gradient instead of a step function. This was necessary to generalize the model to 3-D printing in a room temperature environment without a heated chamber. The thermal equation was calibrated using thermal measurements and validated by measuring curvatures in printed objects. The results confirm that this is a valid model for predicting warpage of thin vertical walls of PLA. Additionally, the effect of annealing was examined. It was found that at a temperature of 50°C, no shrinkage or crystallization takes place, but at 90°C the PLA rapidly crystallizes to around 20% crystallinity. This indicates that heated bed temperatures should be maintained at 50 o C or lower to avoid print failure (premature substrate release) with PLA. At 90°C, the annealing is accompanied by a 5% size decrease in both horizontal dimensions, but an 8% increase in the vertical dimension. Thus, the volume decreased by only 3%. This observation may lead to potential methods of improving slicing of printing large PLA objects with FFF.

Syringe pumps are widely used in a multitude of tasks where precise volumes of an extru-date need to be delivered at a specific flow rate. In the past decade various open source syringe pump designs have accelerated scientific research and exploration by reducing costs and introducing new ideas. To further expand the capabilities of open source syringe pumps we introduce a novel syringe pump design, the Ystruder. It features a load cell to monitor the piston force. This capability enables clog detection as well as development of advanced dosing algorithms. The Ystruder can be monitored wirelessly through a browser-based interface that is integrated into the embedded system. The design is modular and simple which facilitates different syringe and motor configurations, to meet a wide range of use cases. Finally, the Ystruder is not limited to functioning solely as a pump as it can be integrated into a wide range of devices such as three-dimensional motion systems. Here the dosing accuracy and repeatability of the Ystruder are quantified, and we demonstrate its functionality both as a syringe pump and a paste extruder for 3D printing.

Distributed digital manufacturing offers a solution to medical supply and technology shortages during pandemics. To prepare for the next pandemic, this study reviews the state-of-the-art for open hardware designs needed in a COVID-19-like pandemic. It evaluates the readiness of the top twenty technologies requested by the Government of India. The results show that the majority of the actual medical products have had some open source development, however, only 15% of the supporting technologies that make the open source device possible are freely available. The results show there is still considerable work needed to provide open source paths for the development of all the medical hardware needed during pandemics. Five core areas of future work are discussed that include: i) technical development of a wide-range of open source solutions for all medical supplies and devices, ii) policies that protect the productivity of laboratories, makerspaces and fabrication facilities during a pandemic, as well as iii) streamlining the regulatory process, iv) developing Good-Samaritan laws to protect makers and designers of open medical hardware, as well as to compel those with knowledge that will save lives to share it, and v) requiring all citizen-funded research to be released with free and open source licenses.

An open-source 3-D printable laboratory sample rotator mixer is developed here in two variants that allow users to opt for the level of functionality, cost saving and associated complexity needed in their laboratories. First, a laboratory sample rotator is designed and demonstrated that can be used for tumbling as well as gentle mixing of samples in a variety of tube sizes by mixing them horizontally, vertically, or any position in between. Changing the mixing angle is fast and convenient and requires no tools. This device is battery powered and can be easily transported to operate in various locations in a lab including desktops, benches, clean hoods, chemical hoods, cold rooms, glove boxes, incubators or biological hoods. Second, an on-board Arduino-based microcontroller is incorporated that adds the functionality of a laboratory sample shaker. These devices can be customized both mechanically and functionally as the user can simply select the operation mode on the switch or alter the code to perform custom experiments. The open source laboratory sample rotator mixer can be built by non-specialists for under US$30 and adding shaking functionality can be done for under $20 more. Thus, these open source devices are technically superior to the proprietary commercial equipment available on the market while saving over 90% of the costs.

Distributed digital manufacturing of free and open-source scientific hardware (FOSH) used for scientific experiments has been shown to in general reduce the costs of scientific hardware by 90–99%. In part due to these cost savings, the manufacturing of scientific equipment is beginning to move away from a central paradigm of purchasing proprietary equipment to one in which scientists themselves download open-source designs, fabricate components with digital manufacturing technology, and then assemble the equipment themselves. This trend introduces a need for new formal design procedures that designers can follow when targeting this scientific audience. This study provides five steps in the procedure, encompassing six design principles for the development of free and open-source hardware for scientific applications. A case study is provided for an open-source slide dryer that can be easily fabricated for under $20, which is more than 300 times less than some commercial alternatives. The bespoke design is parametric and easily adjusted for many applications. By designing using open-source principles and the proposed procedures, the outcome will be customizable, under control of the researcher, less expensive than commercial options, more maintainable, and will have many applications that benefit the user since the design documentation is open and freely accessible.

Powered by TCPDF (www.tcpdf.org) This material is protected by copyright and other intellectual property rights, and duplication or sale of all or part of any of the repository collections is not permitted, except that material may be duplicated by you for your research use or educational purposes in electronic or print form. You must obtain permission for any other use. Electronic or print copies may not be offered, whether for sale or otherwise to anyone who is not an authorised user. Heikkinen, Ismo T.S.; Kauppinen, Christoffer; Liu, Zhengjun; Asikainen, Sanja M.; Spoljaric, Steven; Seppälä, Jukka V.; Savin, Hele; Pearce, Joshua M. Chemical compatibility of fused filament fabrication-based 3-D printed components with solutions commonly used in semiconductor wet processing

Centrifuges are commonly required devices in medical diagnostics facilities as well as scientific laboratories. Although there are commercial and open source centrifuges, the costs of the former and the required electricity to operate the latter limit accessibility in resource-constrained settings. There is a need for low-cost, human-powered, verified, and reliable lab-scale centrifuges. This study provides the designs for a low-cost 100% 3-D printed centrifuge, which can be fabricated on any low-cost RepRap-class (self-replicating rapid prototyper) fused filament fabrication (FFF)-or fused particle fabrication (FPF)-based 3-D printer. In addition, validation procedures are provided using a web camera and free and open source software. This paper provides the complete open source plans, including instructions for the fabrication and operation of a hand-powered centrifuge. This study successfully tested and validated the instrument, which can be operated anywhere in the world with no electricity inputs, obtaining a radial velocity of over 1750 rpm and over 50 N of relative centrifugal force. Using commercial filament, the instrument costs about U.S. $25, which is less than half of all commercially available systems. However, the costs can be dropped further using recycled plastics on open source systems for over 99% savings. The results are discussed in the context of resource-constrained medical and scientific facilities.