Timeline

September 2020

Results from the first round

Each specimen is measured in width (w) and thickness (t) at 3 points along its constant section length. Average width (w) and thickness (t) were calculated and used for determination of the cross-sectional area (A) of the specimen. The weight (Q) of each specimen is measured with a Mettler PE 600 weighing scale with an accuracy of 0,01 g. From each tensile test the following mechanical parameters were recorded: Young modulus, E; Proof stress at 0,2% deviation, Rp02; Maximum stress, Smax; Strain at max stress, ermax, Failure stress, Sf; Failure strain, ef .For each tested batch, average values and standard deviation have been determined.

August 2020

Phase IV - Test
Test execution and data analysis

A number of 14 makers effectively produced at least one batch for a total number of 23 batches (69 specimens) which have been tested during the Test stage. Tensile tests were performed on submitted batches, according to ASTM D638 standard [16]. A MaCh5 machine, a commercial desktop universal testing machine produced by MaCh3D srl (www.mach3d.it) has been used for tests. The specific machine has a load capacity of 5 kN and a global run of 110 mm. A proprietary conformal gripping system is used which adopts the specific specimen shape as in figure 4 with its dimensions. MaCh5 and the specific specimen gripping ends are discussed in this paper [ LINK > https://doi.org/10.1016/j.prostr.2018.11.078 ].The final test setup is depicted in the image here on the left. Load is measured by means of the onboard 5kN load cell (with an accuracy of 0.005 N). A commercial 3rd party extensometer directly connected to MaCh5 apparatus is used for accurate strain measure; the extensometer gage length is 50 mm. Tests were performed at a crosshead speed of 5 mm/min with 5 Hz sampling rate.

July 2020

Phase II + III - Production + Delivery
Specimen production and delivery

The Production phase started sharing production guidelines to registered makers. Together with the STL file of the specimens to be produced, detailed instructions about printer setup have been shared to participants. A printing job consisted in the production of a Batch of 3 Specimen. Each Maker could participate with a maximum of 5 batches.The unique requirement for the filament was to adopt PLA as base material, with no further specifications, recording filament manufacturer, colour and eventually special characteristics.The production of each specimens batch ended with the Delivery which consists in the registration of the specimens batch on a specific online form, connected with a spreadsheet which automatically collects the entries and generates a unique batch-code and a shipment letter to be attached with specimens.

RR4AM_CALL4MAKERS.pdf

(early) July 2020

Phase I - Recruiting.
Call 4 Makers and onboarding

The Recruiting phase consisted in a Call for Makers (click on the image) addressed to the Makers4Parma network, presenting the research and asking to apply spontaneously to the experiment, producing a batch of 3 specimens from specific geometry and taking care to strictly follow printing guidelines. Applications were collected with an online form. In two weeks, starting from 60 e-mail addresses, 25 Makers got registered.

(late) June 2020

Experiment Planning.

In the last week of June 2020 the RR4AM-M4Pr experiment was designed and baked.The experiment is made of 5 steps:

Recruiting,
Production,
Delivery,
Test
Dissemination.

June 2020

Ideation.

The Covid-19 emergency joined together (remotely) a bunch of makers from our territory putting their effort in Covid-19 fight using 3d printing. A large numbers of adapters, valves and masks have been produced distributively in short time, both by private makers, professional designers/engineers and AM professionals. The community of these people grouped spontaneously under the name of "Makers4Parma" coordinated by FABLAB Parma and Officine ON/OFF.The results of this effort was helpful for front-line health professionals, medical research, rescue operators, medics and paramedics, during the pandemic peak days.When the situation calmed-down what technically emerged is a wide variety of printing results in terms of quality, stiffness and reliability, joined with a lack of mechanical informations and knowledge regarding materials processed.Our RR4AM research generates from this observation, aiming to answer the question: "how different production facilities and operators affects the reliability and the mechanical properties of transformed materials ?"