The following information documents the build sequence involved in making an additive manufacturing unit known as a printrbot. It is to be a visual guide with short comments to briefly describe the steps involved in the build sequence. The Printrbot uses FDM technology to print with thermoplastics such as ABS or PLA. L u c i d C o l l e c t i v e . c o m
base the foundation on which everything is built
attach bearings
insert and secure rods
insert sliding rod
Attach shaft bearings to base piece. Use cable ties to secure into place. Do not fully tighten cable ties yet to allow for calibration later on.
Place horizontal rods (z axis) into either side and secure with bolts. Measure lengths on all four rods to ensure square placement. Place vertical rod (y axis) into existing hole.
Very carefully insert oiled rods into fastened horizontal bearings.
comment: Perhaps a more secure method needs to be used to secure the bearings to the base pieces.
comment: The way the rods are secured using a screw system is good for someone who wants the freedom to tinker till it is right. However a more fluid and reliable way of inserting rod would make this easier
comment: Ensure that you gently and slowly push the rod otherwise the ball bearings will become damaged or fall out.
base motors attaching motors for y(horizontal) and z(vertical) axis
screw in
attach bearings
attach gears and shafts
Screw in 3 base motors into base pieces. 2 z axis motors and 1 y axis motor. Insure that the screws are as tight as possible.
Use a system of washers and bearings to create a smooth environment for the z axis belt to run along.
Attach gear onto stepper motor shaft and secure with screw.. Have the belt running along the gear between the bearings ready for further mounting.. Insert nut into shaft coupler (for z axis) and screw in threaded rod. Attach shaft coupler onto stepper motor shaft and secure with a screw and nut
comment: The base pieces require a lot of strength to be able to hold the motors as securely as possible. This could be improved in the printrbot design where breakage occurred in this area.
comment: It is important that the belt is able to run along the belts very smoothly but also in a tight fashion.
comment: The shaft coupler is effective but not strong,. I think this part needs to be stainless steel or it will continually fail. Coupling with springs made from stainless steel also aids in reducing z axis wobble
bed area which is directly printed onto
secure base to y axis
heat bed
attach y axis belt to bed
Attach the perspex base to the y axis rods. Secure the base using the printed coupling and the y axis rods. It is essential to ensure your rods are running smoothly at this point.
Attach the heat bed using spacers and screws. The heat bed is the printing platform. It heats up to provide a warm build environment which aids in the joining of molten polymer to make a print.
Tension belt using pliers and attach to the printed belt clip (shown in top right corner). Belt clip is attached using screws.
comment. The coupling was not strong enough for long term use. It could be a good idea to replace these with stainless steel or high density prints which can allow some flex.
comment: This piece also has a thermostat attached on the base which is simply secured by cafton tape,. Perhaps this could be secured in a more durable manner.
comment: Belt clips work, but do not hold belt tight for prolonged use. Will constantly need to tightened unless this design uses a better holding mechanism.
hot ends melts the polymer to print with
prepare wiring
ceramic paste
element into hot end
Wiring is held onto hot end using a temporary washer and bolt set up.
Ceramic past is applied to the wired connections around the hot end element to insulate and hold the wiring in place. The paste is wet at first but solidifies with heat. The hot ends are tested to be working with a power supply by wiring to the negative and positive terminals.
Remove temporary washer and bolt and replace with hot end screw.
comment: This process is tedious and messy. The paste is also fairly brittle once hard and can easily break. Perhaps this area of the bot could be improved for greater durability.
comment: Belt clips work, but do not hold belt tight for prolonged use. Will constantly need to tightened unless this design uses a better holding mechanism.
hot ends continued
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thermostat prepared
attach thermostat
attach holder and insulation
Enclose the wires of the thermostat with sleeves to ensure insulation.
Place thermostat onto hot end nozzle and use kapton tape to secure and insulate.
Screw black sleeve onto hot end assembly. Add insulation sleeves.
comments: Insure this is attached securely using kapton tape as it can be quite annoying to adjust later.
comment: Insulation sleeves break fairly easily so be careful when handling.
comment: Best done with a magnifying glass as the wires are very thin and difficult to insert into sleeves.
extruder head combined with hot end to put filament on bed
printed parts combined
bearings and knurled bold
attach drive gear
Printed parts are placed together as shown ready for further assembly.
Insert bearings in relevant places, using knurled bolts and round bar to keep the parts in place. The gnurling of the knurled bolt should line up with the hole running through the extruder head setup.
Remove temporary washer and bolt and replace with hot end screw.
comment. The knurled bolts purchased were to large for the extruder head so washers were used to space out the bolt and insure the gnurling was in the correct place.
comment: Belt clips work, but do not hold belt tight for prolonged use. Will constantly need to tightened unless this design uses a better holding mechanism.
extruder head continued
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motor attachment
hot end placement
attach hot end to extruder
Using screws attach the stepper motor to the extruder head using screws and the 3 places available on the printed extruder parts. Attach the gear to the stepper motor before attaching.
Place assembled hot end onto printed part ready to attached to the rest of the extruder head assembly.
The hot end is attached to the extruder assembly using screws and bolts. It is essential here that the hole in the hot end shaft lines up with the extruder head hole (the hole which the knurling runs above)
comment: It is important that the screws are quite tight to reduce any movement of the gear while printing
comment: The hot end assembly we used was meant for a larger extruder head design (makerbot) so spacers were used to allow for the size difference.
comment: It is essential that all holes line up for smooth extrusion
the x and z axis movement along the x and z axis
insert bearing and bolts
attach motor
mount to base
insert bearings and bolts into 3d printed parts. Insert x axis rods into slots of part.
Using screws attach the x axis stepper motor. Attach the gear to the motor before attaching to the full assembly
Insert smooth rods into holes in base and attach threaded rod to coupling on base stepper motors. You now have a z axis.
comment: Use the bolts inside the printed parts to move the x axis up and down. The bearings run smoothly along the rods to ensure smooth stable movement.
wiring hardware
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attaching the brain to the body
ramp + arduino2560
connect veins
the schematic
Place the Ramps board onto the Arduino2560. Simply line up the pins on the ramps with all the pins on the arduino.
Attach the wiring to the board using simple pin connections. Insert stepper drivers into relevant pins.
Use the schematic supplied by the RepRap wiki found under Ramps 1.4. This is a basic and simple to follow guide to the correct wiring.
comment: Insure all wiring is done to a high level and that no short circuits exist or you will blow up your boards or drivers
comment: If wiring does not automatically work, troubleshoot by isolating each component and running the jog sketch found on the ramps 1.4 wiki page.
software making the brains do what you want
upload sketch
get pronterface and slicer working
Upload the Marlin sketch from your computer to the Arduino via USB. Use the arduino software to do this.
Once marlin is uploaded, open pronterface and check that you have full control of all axis’ and that the thermostats and heating elements are working. Then using Slic3r within Pronterface upload and STL file and cross your fingers.
Calibrate and calibrate again until you are printing 20ug layers.
comment: You will now have to troubleshoot calibration issues. This is where all the fun starts!
comment: 1) patience and persistence = much needed 2)??? 3)Profit.
comment: The arduino software can also be used to upload the jogging sketch found on the Ramps1.4 wiki page to troubleshoot motors and heating issues