13. Applications and implications¶

The objective of the tank is to store the material before it is extruded. It also has to apply enough pressure to the material to generate a flow that goes to the extruder, lets remember that most of this materials are viscous, and are suffering of pressure loss.

There are 2 ways of applying this pressure, using a motor (DC or stepper) or using an air pump.

Extruder¶

They are different forms to give a more constant flow to the extruded material:

Aplying a constant pressure directly to the material: 2

Auger Screw 3

I’m working at the moment in a tank + auger screw extrusion system.

What materials and components will be used?¶

I am not completly sure of how the project will look at the end of the hole process, but this is the listof materials I expect to use: - EcoFlex for molds

3D printer filament
Stepper motor Nema 23 and 17
Motor coupling
Auger Screw
Linear Bearings
Ball Bearings
Linear Axis

Where will they come from?¶

This question is answered in the following two questions.

How much will they cost?¶

Qty	Description	Price	Link	Notes
2	LM8UU Linear Bearings	1.00 $	https://www.amazon.com/gp/product/B0711SNV4N?pf_rd_p=1581d9f4-062f-453c-b69e-0f3e00ba2652&pf_rd_r=R9JVPX22R85X7FW7D5QV	Order many, as those packages are more convinient than the unit price.
2	Chrome Linear Guides	6.00 $	https://www.amazon.com/dp/B07H9HDNYP/?coliid=I3FH7XXY9FZOZL&colid=IKZOWO2NXR68&psc=0&ref_=lv_ov_lig_dp_it
1	Nema 23 Steel Mounting Support	6.59 $	https://www.amazon.com/Stepper-Bracket-Support-Mounting-Engraving/dp/B075L92Y6B/ref=sr_1_1?keywords=nema+23+base&qid=1553722704&s=gateway&sr=8-1
1	Nema 23 Lead Screw	112.49 $	https://www.amazon.com/STEPPERONLINE-Precision-Actuator-External-1-5875mm/dp/B07PTZ8JN4/ref=sr_1_5?crid=2S7PKB6A38INJ&keywords=nema+23+lead+screw&qid=1553722758&s=gateway&sprefix=nema23+lead%2Caps%2C135&sr=8-5
1	Ball Bearing	6.97 $	https://www.amazon.com/ABI-Enduro-cartridge-bearing-9-5x22-2x7/dp/B001GSKOB0/ref=sr_1_18?keywords=ball+bearing+9.5mm&qid=1553723200&s=gateway&sr=8-18	This one is expensive, but you just need it to fit your lead screw from the motor.
2	O’Ring	1.52 $	https://www.amazon.com/uxcell-Rings-Nitrile-Rubber-Diameter/dp/B07HRRTRP9/ref=sr_1_13?keywords=o+ring+50mm&qid=1553723371&s=gateway&sr=8-13	I used a 50mm diam with a 3mm thickness
1	Thread Seal	1.2 $	https://www.amazon.com/Everflow-811-5-Thread-Plumbers-White/dp/B00538ITFW/ref=sr_1_2?keywords=teflon&qid=1553723450&s=gateway&sr=8-2
1	Ultimaker Filament	75 $	https://www.amazon.com/Ultimaker-2-PLA-Filament-Blue/dp/B00NLK1DF2/ref=sr_1_1?keywords=ultimaker+filament&qid=1557012734&s=gateway&sr=8-1
1	EcoFLex	39 $	https://www.amazon.com/Ecoflex-00-30-Super-Platinum-Silicone/dp/B00CA5VY3U/ref=sr_1_2?keywords=ecoflex&qid=1557012799&s=gateway&sr=8-2
1	Nema 17	14 $	https://www.amazon.com/JoyNano-Stepper-Bipolar-Holding-2-Phase/dp/B07DPFD22K/ref=sr_1_fkmrnull_1_sspa?keywords=nema+17+jameco&qid=1557012860&s=gateway&sr=8-1-fkmrnull-spons&psc=1
1	Nema 17 Motor coupling	7.86 $	https://www.amazon.com/OctagonStar-Flexible-Couplings-Printer-Machine%EF%BC%882PCS%EF%BC%89/dp/B01HBPHSII/ref=sr_1_5?crid=25O74Q4U4EBDL&keywords=flexible+couplings+5mm+to+8mm+nema+17+shaft&qid=1557012921&s=gateway&sprefix=coupling+nema+%2Caps%2C126&sr=8-5	Its a pack of 2 coupling

*This costs are an estimation and could vary through the finnal project development.

What part or systems will be made?¶

From the tank:

In case it is motor based:

The whole piston system, and the parts that ataches the system to the machine.

A first version has already been developed, you can see it in this link

In case I use the air system:

I will buy a syringe that will act as a tank, so I will build the closure, and seals for the air system.

From the extruder:

I will build the whole system, with the expception of the motor.

This includes:

Auger Screw
Auger Chamber
Motor Base
Motor Coupling
Nozzle
Seal

What process will I use?¶

3D printing
Laser cutting
Molding and casting

What question needs to be answered?¶

In the case of the BioMtaterial 3D printing, the main challenge I will face is the capacity that this material has to be 3D printed. It has to fullfil two requierments:

Having a low enough viscosity to enable the material to flow through the tank and extruder.
Sustain itself in order to make a layer based part.

In case the material fails, I am going to test the system using clay, a material that has been proven to work.

How will it be evaluated?¶

The competence of the 3D printer extruder to work with a viscous material.