Catch Us at SXSW 2017!

SXSW prep is in full swing and we can’t wait to see you!

You can connect with re:3D and Gigabot at the events below:

Do you have a request for another event Gigabot should visit?

~Email info@re3d.org with your tips!

Additive Value for Your Subtractive Manufacturing

Below is Gigamachinist's Steve Johnson's first blog on 3D printing for re:3D's Gigabot fabrication shop.

 Additive Value for Your Subtractive Manufacturing

by Steve Johnson

You may be thinking: “Why would a machine shop need a 3d printer?”

Turns out there are a lot of uses! In my case, we needed to make new fixtures to take advantage of the capabilities of our new 4th axis and the full travel of our machine.  When making fixtures, cost is always a main concern, and making a bad fixture can be expensive in terms of both material and man hours.

By using re:3D’s Gigabot 3D printer, we were able to design our fixture in Solidworks, export the model, and print a full size model of the fixture overnight on Gigabot (no time wasted).

This morning, we tapped the holes for our cam clamps, put the printed fixture into the machine, and checked for clearance and travel issues. In the process we found two issues that we corrected in the solid model, and we are now printing the revised test fixture.

Without the benefit of Gigabot, we may have wasted a 4in diameter by 20in long piece of material, as well as hours of labor. Right now, our only cost has been a few dollars worth of plastic.

This experience has been a great opportunity for me to learn Solidworks and I’m looking forward to using Gigabot again to cut costs, create efficiencies, and to have fun in the shop!

~Happy Printing!

Steve Johnson

Blog Post Author

Filament Testing – Scorpion Flexible Nylon by Black Magic 3D

Below are our notes that respect our new open source filament testing. ASTM test samples are being created and in the upcoming months you can anticipate a summary on our website that reflects our adventures in 3D printing material science. 

Material Tested: Scorpion Flexible Nylon

Manufacturer: Black Magic 3D

Filament Diameter: – 2.85mm

Color Tested: Natural

Date Tested: 4/06/2016

OBSERVATIONS

Ease of use: Those new to 3D printing may want to budget extra time when printing with Scorpion as it takes a little manipulation to perfect the temperature & retraction settings.

Appearance: The natural filament was clean and consistent. Prints matched filament color & opacity.

Size consistency: Awesome, less than 0.1mm within the roll.

Color consistency: Great, consistent throughout the coil.

SETTINGS

Print temperature: 230-235 C (suggested): nozzle / 60C : bed

Printer Used: Gigabot

Speed: 50 mm/s

Layer Height: 0.3mm

Infill: 15%

Type(s) of print surface used: PRINTnZ with 3M Blue Painter’s Tape and 2 coats of Elmer’s Glue Stick

List of test files printed: re:3D’s test files 1, 2, and 3 (logo, vase, and Benchy Torture Test)

You view watch a video summarizing our testing below:

FINDINGS

Odor: None

Bed adhesion (1: terrible – 5: fabulous!)

  • 4- Great adhesion could be achieved, but required two coats of PVA glue stick, painter’s tape, and the highest heat setting suggested for the bed and nozzle.

Stringing (1: lots – 5: none!)

  • 4 -Stringing was observed across lettering, however doubling the retraction settings eliminated the problem.

Shrinkage (1: lots – 5: none!)

  • 4- Some curling was observed on corners of logo after removal. It is suggested that the print be allowed to cool down on the bed before taking it off.

Interlayer adhesion (1: terrible – 5: fabulous!)

  • 5- Perfect!

NOTES:

  • A flexible nylon offers a lot of possibility to the 3D printing community
    • This filament appears to overcome concerns that both flexible and nylon materials are difficult to use.
    • With the right settings and adhesion hygiene, this material appears to yield consistent, quality prints.
  • NOTE: this filament required 2 coats of Elmer glue stick on Blue Painter’s tape applied over a heated bed, using the max range of bed and nozzle heat settings
  • Filament size consistency was excellent.
  • Curling was observed with only 1 coat of glue stick and was also seen after print removal when the bed was still warm.
    • It is recommended that the bed be allowed to cool before removal to mitigate curling after print completion.
  • The best testing outcomes were observed at the highest temperatures settings (235C -nozzle, 60C- bed) and using the speed (50mm/s) that the manufacture provided. No guidance was given for retraction, which we found we needed to double or standard setting in order to eliminate stringing across lettering.
  • The unboxing experience was well done and the recommendation sheet was very useful. 
    • No date stamp for production was listed, however a batch number was provided for traceability.
    • Manufacturer recommended settings were easily referenced on the enclosed documentation.

RECCOMENDATIONS:

  • This filament is extremely impressive and more than exceeded expectations due to past expereinces working with nylons and flexible materials.
  • Upon review, we would highly recommend that larger, more complex prints be created to further investigate the potential this exotic, and much needed material provides.

Want to chat? Join our forum where we have initiated a thread about our experience!

https://re3d.zendesk.com/hc/en-us/community/posts/206375086-Testing-Scorpion-Flexible-Nylon-on-Gigabot

~Happy Printing!

Samantha snabes

Blog Post Author

Filament Testing – 3D Fuel Advanced PLA

Below are our notes that respect our new open source filament testing. ASTM test samples are being created and in the upcoming months you can anticipate a summary on our website that reflects our adventures in 3D printing material science. 

Material Tested: 3D FUEL/APLA

Manufacturer: 3D Fuel

Filament Diameter: – 2.85mm

Color Tested: Bright green

Date Tested: 2/29/2016

OBSERVATIONS

Ease of use:  Extremely printable with excellent adhesion.

Appearance:  The green filament was vibrant with a smooth texture. Prints yielded a slightly “shiny” surface.

Size consistency:  Average, within .1mm within roll.

Color consistency: Great, consistent throughout roll.

SETTINGS

Print temperature: 210 C (nozzle) / 55C (bed)

Printer Used: Gigabot

Speed: 45 mm/s

Layer Height: 0.3mm

Infill: 30%

Type(s) of print surface used: PRINTnZ

List of test files printed: re:3D’s test files 1, 2, and 3 (logo, vase, airplane gear piece)

 You can watch a video  summarizing our testing:

FINDINGS

Odor: None

Bed adhesion (1: terrible – 5: fabulous!)

  • 5 (only the settings listed above were tested, but the manufacturer’s recommendations seemed to be accurate)

Stringing (1: lots -5: none!)

  • 5 – None!

Shrinkage (1:lots-5: none!)

  • 5-None!

Interlayer adhesion (1:terrible-5:fabulous!)

  • 5- Perfect!

NOTES:

  • The promise of a more heat resistant PLA is super enticing to the 3D printing community.
    • After testing, the landing gear was exposed to high temperature heat via a hair dryer and showed little warping.
      • Further controlled testing would need to be implemented to investigate this claim, but it does initially appear to be stronger and more heat resistant than traditional PLA.
  • NOTE: this filament was tested 4 months after receipt, however, for many users a 4 month shelf life is necessary.
    • Testing fresh filament is expected to yield similar or even better results.
  • Filament size consistency was about on par with most filament.
  • No delamination or curling was observed.
  • All testing was conducted at the midpoint of the temperature and speed range that the manufacture provided. It’s likely that the outcome would have been even better had the ranges had been explored in more detail.
  • The unboxing experience was well done and the recommendation sheet was highly professional.
  • We appreciated the Made in America reference, and date stamp of quality control on the box & insert.
  • Manufacturer recommended settings were easily referenced on the enclosed documentation.

RECCOMENDATIONS:

  • This filament is extremely impressive and more than exceeded it’s claims.
  • Upon review, we would highly recommend that this filament be submitted to ASTM testing by evaluating coupons at multiple temperature and infill settings.

Want to chat? Join our forum where we have initiated a thread about our experience!

https://re3d.zendesk.com/hc/en-us/community/posts/205198503-TESTING3D-FUEL-APLA

~Happy Printing!

Samantha snabes

Blog Post Author

The Next Generation of Gigabot

Our engineers have been hard at work over the past several months making some improvements to the current model of Gigabot, and we are excited to announce that we will be releasing this new version this fall.

In October 2015 we will release what you may hear us refer to as “GB3,” or the third generation of Gigabot since its inception.  With this new version will come several tweaks and additions, the full list of which is below. We took the first of GB3 model to Roosterteeth today were it will be undergoing extensive field testing over the next two months. This Gigabot will also be filmed so we can release detailed 360 footage to you prior to the official release.

Current Gigabot-owners, not to worry – you will not be left behind.  All the alterations and additions will be available as retrofit kits so that anyone can upgrade their current Gigabot.  We want to ensure first and foremost that you are taken care of, so we will be making these retrofit upgrade kits available for purchase to you before we begin offering GB3 to the general public.

With these changes and additions comes an increase in the current price of Gigabot.  We want to give as much advance notice as possible about this, so our first priority is getting this message out.  Unfortunately this means that at this time we do not have finalized prices on the new Gigabot or the retrofit kits, however as soon as we do we will put out that information.

We are excited for the community to get their hands on the new and improved Gigabot, and we look forward to hearing what you think of it!  Please don’t hesitate to contact us with any questions at sales@re3d.org.

New Gigabot Changes/Additions

  • Ready for dual extruders (base model with single extruder)
  • Extruder with all-metal gearbox
  • All-metal E3D hotend with 0.4mm nozzle
  • Thermocouple temperature sensor instead of thermistor
  • Out-of-filament detection
  • Cable tray wire management for better print quality and increased reliability
  • Partial side panels standard
  • Viki 2.0
  • More accessible power switch and bed height adjustment
  • Optional tablet holder

Starting 1st September These Configurations Will Be Listed for Sale:

  • GB3 Variants
    • GB3 Single Extruder Kit
    • GB3 Dual Extruder Kit
    • GB3 Single Extruder Fully Assembled
    • GB3 Dual Extruder Fully Assembled
    • GB3XL Single Extruder Fully Assembled
    • GB3XL Dual Extruder Fully Assembled
      • All of these variants include:
        • Filament Detection
        • E3D Hot End (Thermocouple Included)
        • Cable Carriers and mounts
        • Power Button Relocation
        • Z-Limit Switch Relocation
        • Center Panels
        • Viki 2.0
        • Viki Holder

These Current Gigabot (aka GB2 : Pre-Oct1 2015 Gigabots) To GB3 Retrofit Kits will also be offered:

  • GB2  and GB2 XL upgrades
    • GB2 & GB2 XL Cable Carrier Upgrade
      • Includes:
        • Cable Carrier
        • Printed parts
          • Trolley electrical box cover
          • X/Y Upright
          • X carrier supports
          • Y carrier supports
          • Z bed side bracket
          • Z frame side bracket
        • Head cable
        • Extruder motor cable
        • X motor cable
        • X limit switch cable
        • Nuts and bolts
    • GB2 & GB2XL -> GB3 & GB3XL Single Extruder Upgrade
      • Includes a redesigned cold and assembly as well as the retrofit kits below:
        • Filament Detection
        • E3D Hot End (Thermocouple Included)
        • Cable Carriers and mounts
        • Power Button Relocation
        • Z-Limit Switch Relocation
        • Center Panels (An $85 discount will be applied for customer who already possess center panels)
    • GB2 & GB2XL -> GB3 & GB3XL Dual Extruder Upgrade
      • Includes a redesigned cold and assembly for a dual extruder as well as the retrofit kits below:
        • Filament Detection
        • E3D Hot End (Thermocouple Included)
        • Cable Carriers and mounts
        • Power Button Relocation
        • Z-Limit Switch Relocation
        • Center Panels (An $85 discount will be applied for customer who already possess center panels)

Pricing:

GB3 Single Kit $8,550.00
GB3 Dual Kit $8,950.00
GB3 Single Extruder Fully Assembled $10,950.00
GB3 Dual Extruder Fully Assembled $11,950.00
GB3XL Single Extruder Fully Assembled $12,950.00
GB3XL Dual Extruder Fully Assembled $13,950.00

 Retrofit Options for Current Gigabot Owners

GB2 Cable Carrier Upgrade (Standard & XL) $395.00

GB2 to GB3 Single Upgrade (Standard & XL): Includes Out of Filament Detection, Power Switch Relocation, Cable Carrier Upgrade, Z Limit Switch Upgrade, Center Panels, Pre-assembled & Improved Hot/Cold End

 $1,295.00

GB2 to GB3 Dual Upgrade (Standard & XL): Includes Out of Filament Detection, Power Switch Relocation, Cable Carrier Upgrade, Z Limit Switch Upgrade, Center Panels, Pre-assembled & Improved Hot/Cold Ends

 $1,695.00

Stand Alone Add-ons

Second Extruder Drop in hardware $495.00
Viki 2.0 (only needed by GB2 owners) $295.00
Filament Detection (1 Left or 1 Right) $75.00
Z-Limit Switch Relocation $95.00
Center Panels (Fit all GBs) $125.00
GBx Front and Rear Panels $185.00
GBx All Panels $300.00
GBxXL Front and Rear Panels $220.00
GBxXL All Panels $325.00
Power Re-location switch Only Available in Single and Dual Upgrade Packages
Wheels Kit Low-6’’  (Tall-16’’) $200.00 ($350)
Wheels Kit XL Low-6’’ (Tall-16’’) $225.00 ($375)

SXSW Innovation Award/ Kickstarter Announcement

We’re incredibly flattered to be nominated for SXSW Innovation Award! The other nominees are amazing and we can’t wait to meet them! Check out the clip below to meet the team below and feel free to show your support by using the following social media mentions : @re_3D #openGB #InnovationAwards. Also, check back for a not-so -surprise Kickstarter campaign for OpenGB during SXSW where we will be seeking your feedback on what you want in Gigabot going forward!!

Forever grateful:

 @

Getting a Grip : Part 1

Getting a grip on your 3D printer filament-Part 1

With the rise in popularity of low cost 3D printers for use in homes and small business many new printer designs have recently arrived in the market. The cost of ownership for 3D printers is coming down which is driving up access in new markets. With a customer base growing outside of engineers and tinkerers it is important that 3D printers must remain near 100% reliable with near zero failed prints due to mechanical and electro-mechanical malfunctions.

One of the leading causes of print failure is the filament feeding mechanism. By surveying the literature and leveraging our current experience in hardware development we have identified a gap in the knowledgebase for understanding the mechanics and operations surrounding the extruder drive gear commonly used on FFF type 3D printers.

We have found reliability of the filament feed gear is dependent upon three factors 1) amount of contact surface are between the drive gear and the filament, 2) depth of the gear’s tooth engagement into the filament 3) number of teeth engaged in the filament at any one time and 4) the direction of the force vector imparted from the filament drive gear into the filament. R&D at re:3D delved into this problem and below is result of their work.

Figures 1 and 2 below shows a 3D rendering of the filament drive gear “Jaws” that will be mounted to the shaft of a geared NEMA 17 stepper motor.

Figure 1. Jaws filament drive gear. Figure 2. Mid-section view of Jaws filament drive gear

The Jaws filament drive gear is machined using a four axis Bridgeport CNC milling machine. In the design process our aim was to optimize the four variables stated above.

  • The amount of contact between the drive gear and the filament is maximized by machining the gear teeth using a cutting tool of the same diameter as the filament it will drive. In our case the filament is 6.0mm in diameter.
  • The depth of tooth engagement was optimized by balancing greater tooth engagement with number of teeth engaged into the filament at any one time. If the tooth engagement is too shallow there will be too little surface area and force imparted to the filament and the teeth will slip and shred the filament. If the tooth engagement is too great the risk of plastic deformation causing the filament dimension to be out of spec for the hot-end and will cause jamming of the hot-end during printing.
  • The number of teeth engaged into the filament at any one time is important in maintaining a smooth and constant push of filament into the hot-end. Consider the job of the filament drive gear is to transform the rotational motion from the stepper motor into straight line movement of filament into the hot-end. If too few gear teeth are engaged into the filament the linear motion of the filament over time will assume more of a sine wave pattern than a constant straight line movement.
  • The force vectors should be directed in the downward direction as much as possible to increase the conservation of energy in the system. Any forces imparted into the filament in the lateral direction will cause plastic deformation of the filament and not translated into pure downward force of the filament feed. It should be noted there will always be a certain amount of lateral force experienced for the pure fact that the drive teeth will need to be engaged into the filament. By studying the section view in Figure 3 below you can see the depth of engagement, the number of teeth engaged and the force vector for a 25 tooth drive gear.
Figure 3. Tooth engagement, number of teeth engaged and force vectors

We are extremely excited to have optimized the design and manufacturing of this advanced filament drive gear for FFF style 3D printers. You can view a short video of the machining process on our re:Tech YouTube channel:

Stay tuned for part two in this series where we will perform data collection and force measurement in a real world application of the Jaws filament drive gear.

Matthew Fiedler

Blog Post Author

re:Tech – Extended Watch Dog

Secondary Micro Controller connected to single board computer by UART

Arduino Mini Pro from Sparkfun ($10) (open source)

Features:

  • ATmega328 running at 16MHz with external resonator (0.5% tolerance)
  • 0.8mm Thin PCB
  • USB connection off board
  • Supports auto-reset
  • 5V regulator
  • Max 150mA output
  • Over current protected
  • Weighs less than 2 grams!
  • DC input 5V up to 12V
  • On board Power and Status LEDs
  • Analog Pins: 8
  • Digital I/Os: 14

Filament Monitor

Filament usage monitoring concept, which uses a filament switch, and mechanical encoder to measure how much filament has been used and if it runs out.  The encoder can also measure if the filament is still moving to detect if the hot end has jammed.

Internal lighting

OpenGB will include fade-able internal LED light strips controlled by the Arduino mini, with the option of having a proxy sensor to fade the light on when a user walks up to the printer.

Proxy Sensor Features

  1. Distance measuring range: 20 to 150 cm
  2. Analog output type
  3. Package size: 29.5×13×21.6 mm
  4. Consumption current: Typ. 33 mA
  5. Supply voltage: 4.5 to 5.5 V

Stepper Motor Fault Detection

Detection for over temperate, over current, under current, and skipping will be included in the Arduino Mini Pro or through the main controller.

Nozzle Crash Detection

Accelerometer mount on the trolley can report spikes in acceleration, including in the Z directions.  This is an experiment addition to better detect nozzle crashes.

Features:

  • Operating Voltage: 1.8V – 3.6V
  • Typical Current: 300 μA
  • Range: ±3g
  • 3-axis sensing
  • Bandwidth adjustment with a single capacitor per axis
  • 1x Mounting Hole

 

Redundant Temperature sensors on Extruders and Bed

These can use the same circuit as the main control board.

Ambient Temperature and Humility

Features:

  • 3.3-6V Input
  • 1-1.5mA measuring current
  • 40-50 uA standby current
  • Humidity from 0-100% RH
  • -40 – 80 degrees C temperature range
  • +-2% RH accuracy
  • +-0.5 degrees C

Patrick finucane

Blog Post Author

How to take your Gigabot Off-the-Grid

One of our values at re:3D is to provide 3D printing technologies to communities around the globe, many of whom don’t have the resources we take for granted.  Access to plastic feedstock, a consistent power infrastructure, and reliable shipping services have always been a requirement to play in the 3D printing space. We want to change that. One of the microsteps in this direction is to find other ways to power our 3D printer, the Gigabot, while still allowing multi-hour (and sometimes multi-day) prints to emerge from our 600mm X 600mm (2ft X 2 ft) build platform.

I started experimenting this past week using a 40W solar panel and a car battery, and had some success printing a small test print. I’ve gotten some questions since then and wanted to explain a little more about my setup, and also find out if there were any other (successful or not) attempts to take YOUR 3D printer off-the-grid.

MY SETUP

Our Gigabot takes 110V or 220V mains power, but then immediately feeds that to a 24V power supply to power the motors, hot end, sensors, USB comm port, and display. The only part that makes use of the mains power is the heated bed (the one that can fry an egg).  Since using PLA as an input material usually eliminates the need for a heated bed, I started there.

Disconnecting the power supply completely, I wired the 12V battery directly to our controller board and internal cooling fan. I later learned that this cooling fan was a great audible indicator of voltage levels – but more on that later.  12V is at the very low end of what our controller board can take in, but the real question was how long could it print for?

THE PHYSICS

I like to equate electricity to water coming out of a hose (like in this great tutorial from SparkFun), so to follow that analogy, I had to figure out if I could hold enough “water pressure” (voltage) to keep the controller alive, a large enough “holding tank” (car battery) to last for the entire print, while using solar panels to add enough “water” (power) to the system during the print.

After testing with a multimeter, I saw that the Gigabot draws about 5A at the most, and less than an Amp when idle (to keep the controller and comms alive), and on average about 3 or 4 Amps while printing (since the heating element cycles to maintain a constant temperature). Judging by the rating on my car battery of 70 Amp-hours, I could count on about 14 hours of power.

I should add that we often exchange Amps and Watts freely when comparing power levels. They are only interchangeable if the volts of the system remain constant (12V or 24V for Gigabot, 120V for USA Mains, etc.), since Power (Watts) = Current (Amps) * Voltage (Volts).

Or per the above analogy: Ability to Remove Mud From Car = Size of Hose * Water Pressure.

THE EXPERIENCE

The solar panel I bought from Fry’s was impressive, but at 40W I know it wouldn’t get to the levels I needed, and I could only afford to experiment with one. Plus, pausing a print when the sun goes behind a cloud just isn’t practical, since it would leave many marks of semi-melted plastic along the way, and the stepper motors would lose their homing location. I knew that the final solution would at least rely on some battery power.

We all know what happens when our car battery is suffering when you try to start it: the lights get dim, you turn off everything electrical, and pray that it turns over and you can get home that night. Instead of a gasoline powered motor and alternator to keep the battery alive, I had a solar panel – and it had to last the entire print. So I had some questions – and like any former space station flight controller, I took lots of data.

THE QUESTIONS

Would 12V be enough to power a system that we have been used to operating at 24V since the very early days? Would my Gigabot’s hotend pull down the stepper motors too far on battery power and affect the success of the print? Could I use all of the available power in the car battery to make a large enough object without any transient errors? Could I turn on and off the solar panel or battery charger during a print without interrupting it?

THE RESULTS

At first things looked (and sounded) gloomy. The first few attempts failed, and it seemed that the battery just didn’t have enough power to drive the hotend, motors, and electronics to keep the voltage levels high enough. Even the fan noise sounded sickly – a lot worse then when I had it set up without the multimeter.

The multimeter! That was it!!

I had wired my multimeter in line with the positive line off the battery to read a super accurate space-rated amp-draw during the entire print. I had wanted to measure exactly how much was going in and out of the solar panel, and the battery. The measurement itself was actually resisting the flow of electricity (the equivalent of bending the water hose to hear if water is rushing past the fold in the line). Once I removed the multimeter and tracked only the voltage across the battery terminals, I was able to get over 13 hours of continuous printing time out of my Gigabot – enough to print this 300mm (12-inch) tall vase! Here are the (manually entered) data points for that one:

The solar panels are pretty straightforward, and work very similar to the battery charger I plug into the wall, so for the purposes of my experimentation in the garage, I’m alternating printing on battery power with a charger on/off, solar panel connected/disconnected, at varying voltage levels of the battery. I think I have found the limits, since my prints start failing at just about 11V on the battery now.

Also, ever since I automated my data taking process, I get much more sleep at once, without needing to wake up for data takes with pen and paper (and help from Google Sheets). Check out the new and improved version with a little help from plotly!

An interesting part of this method of gathering data is that you can start to see the cycling of the cartridge heater very clearly as the extra current draw pulls the battery voltage down each time the hotend is full-on. This will be useful in tweaking my PID values no doubt, and could also lead to better methods of insulating the hotend so it doesn’t need to heat up as much, thereby saving valuable amp-hours!

NEXT STEPS

Clearly there is a little more work to do before we have a brownout-proof or solar-ready Gigabot out of the box, but I think these experiments prove it’s within the realm of possibility to create 3D objects anywhere – given a robust enough printer, and a light bulb’s worth of energy and imagination.

Chris Gerty

Blog Post Author

re:Tech – Control Board

Controller

The new controller for OpenGB is loosely based on the open source RAMPS 1.4 control. The RAMPS 1.4 controler mounts on an Arduino Mega as an extension board (known as an Arduino Shield). The goal of the OpenGB controller is to include the following: motor driver for each motor, thermo couple and thermo resistor inputs, enough MOSFET power output for dual extruders, fan, and bed relay, endstops, and extra serial port terminals. This configuration keeps all of the active components on the professional board (arduino) and allows us to design with (mostly) with passive components.

The controller board will include the following features:

Stepper Motor Driver Sockets (7 drivers)

A total of seven motor drivers will be included, one (1) for the X-Axis, two (2) for the Y-Axis, two (2) for the Z-axis, and two (2) for extruders. The sockets are based on the Ti DRV8825 chip carrier board available from a number of suppliers and are currently used in the Gigabot 2.0.

The sockets will also add support for the fault and VREF pin on the Sure Step carrier boards. This will allow for better error detection and for programmatically setting the current of each driver.

Preliminary Motor Driver Socket Schematic

Thermocouple Support (3Circuits)

Two thermocouple inputs will be included in the preliminary controller. They will be based on the AD8495 chip.

Thermo Resistors (4 Circuits)

Four thermo resistor inputs will be included in the preliminary controller. They can be used for controlling the temperature of the two extruders or monitoring the temperature at other locations on OpenGB. The inputs can also be used for other analog sensing needs.

End Stop Terminals (8 terminals)

Eight (8) end stop inputs will be included in the preliminary controller. They will be labeled X-min, X-max, Y-min, Y-max, Z-min, Z-max, Filament Out, and extra.

Power Mosfets (4 circuits)

Four (4) power mosfets circuits will be included in the preliminary controller, based on the STP55 mosfet which is rated at 55 amps. Each circuits includes a indicator LED. The Circuits will be labeled Extruder 1, Extruder 2, Bed Relay, and Extra.

Serial Connections (2 terminals)

The arduino serial connection UART 0 and UART 1 will have terminals for easy integration. The SPI and I2C ports will also be broken out for onboard access.

These can will used in future iterations to avoid going through the USB hub with a direct UART to UART connection between the single board computer and the controller.

Reset Switch and Input

A reset switch will be included on the control board. There will also be a terminal block for an external reset switch. This switch should not be necessary for any normal operation.

Input for Induction bed Sensor

A single voltage divider will be included to enable the use of a bed touch less bed sensor to be used as the Z min limit switch

First revision is shown below, but I am assuming that it is going to change. After we test it I will post the design files, so you can take a look.

Patrick Finucane

Blog Post Author