RepRap Prusa i3 Manual

Prusa i3 – Build Manual
Table of Contents
Forward............................................................................................................................................................................... 4
1. Y-AXIS Frame...............................................................................................................................................................5
1.1 Y-AXIS Long Sections.................................................................................................................................................................5
1.2 Y-Axis ear Section (Motor)........................................................................................................................................................6
1.3 Y-Axis Front Section (Idler).........................................................................................................................................................8
1.4 Y-Axis Lower Frame Completed..................................................................................................................................................9
2. Z-AXIS Frame.............................................................................................................................................................10
2.1 Z-Axis Frame Mounting.............................................................................................................................................................10
2.2 Z-Axis Top/Bottom mounts (PLA)............................................................................................................................................12
2.3 Z-Axis Motors & End-stop.........................................................................................................................................................13
3. Build Plate & Heated Bed...........................................................................................................................................14
3.1 Build Plate Mounting..................................................................................................................................................................14
3.2 Y-axis belt...................................................................................................................................................................................15
3.3 Heated Bed Mounting.................................................................................................................................................................17
4. amps Mounting.........................................................................................................................................................18
4.1 amps mount..............................................................................................................................................................................18
4.2 amps Y & Z Wiring..................................................................................................................................................................20
5. X-AXIS + Z-AXIS ods.............................................................................................................................................23
5.1 X-Axis Assembly........................................................................................................................................................................23
5.2 X-Axis Mounting........................................................................................................................................................................27
6. Extruder & Hot-End...................................................................................................................................................32
6.1 Hot-end Mounting .....................................................................................................................................................................32
7. X & Z-Endstop Triggers.............................................................................................................................................38
7.1 X-Endstop Trigger......................................................................................................................................................................38
7.2 Z-Endstop Trigger.......................................................................................................................................................................39
8. Final AMPS Wiring..................................................................................................................................................40
8.1 Heated Bed Connecting..............................................................................................................................................................41
8.2 Build Plate Fans Connecting......................................................................................................................................................41
8.3 Hot-End Connecting...................................................................................................................................................................41
8.4 Power Supply / Hot-End Fan and AMPS Fan Connecting.....................................................................................................42
9. Spool Mount................................................................................................................................................................ 44
9.1 Spool Mount Assembly..............................................................................................................................................................44
10. LCD / LCD Case & Mount........................................................................................................................................45
10.1 LCD Case Assembly.................................................................................................................................................................45
10.2 LCD Wiring .............................................................................................................................................................................46
11. First Power-on and Test.............................................................................................................................................47
11.1 First Power-on...........................................................................................................................................................................48
11.2 Motor Tuning (For reference, should not be required).............................................................................................................49
11.3 Filament Feeding......................................................................................................................................................................50
11.4 Extruder Calibration (Optional)................................................................................................................................................52
11.5 End-stop Test.............................................................................................................................................................................52
11.6 Bed Levelling Preparation........................................................................................................................................................53
11.7 Bed Levelling............................................................................................................................................................................54
11.8 First Print..................................................................................................................................................................................55
Appendix A – Motor Wiring.............................................................................................................................................57
Appendix B – Idler Pulleys...............................................................................................................................................63
Appendix C – Power Supply Wiring................................................................................................................................66
Appendix D – Firmware Update .....................................................................................................................................68
Appendix Z – Troubleshooting.........................................................................................................................................69
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Prusa i3 – Build Manual
Kit Parts :
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Prusa i3 – Build Manual
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Prusa i3 – Build Manual
Forward
This manual is intended as a guide to your EP AP Prusa I3 build, it would be impossible to cover everything
involved in building and tuning a EP AP Prusa I3 in a single 80 page guide, but it will greatly smooth the
way to getting you up and running quickly. You are strongly encouraged to consult some on the many other I3
resources online especially the AMPS 1.4 wiki (http://www.reprap.org/wiki/ AMPS_1.4) and other online
Prusa I3 build manuals such as (http://reprap.org/wiki/Prusa_i3_Build_Manual). This is especially true when
you come to tuning your printer during your first prints. Above all, you can build a EP AP quickly but never
build one rushed. Every nut and bolt thats perfectly tensioned, every rod that's perfectly aligned (especially the
base), every bearing that's perfectly seated .. they will all translate to better print quality. The electronics are
doubly important, check and triple check every connection is correct,tight and secure before powering up to
avoid costly and time consuming mistakes!
Safety Notes:
High Current : Building and Operating a EP AP involves high current, especially for the heated bed
which can draw 10A on its own. All cables should be securely connected and checked. All high current
connections should be well insulated to avoid contact and well secured to prevent movement at the points
of connection.
High Temp : A EP AP hot-end can reach well in excess of 200c , caution is advised during operation.
High Forces : A EP AP motor can exert considerable force, caution is advised putting your hands near
any of the axis while in operation
Fire isk : An operating EP AP is a non-negligible fire risk. Don't ever leave one running un-
attended. It would be advisable to have an electrical fire extinguisher on hand while operating a
EP AP. All of the high current and high temperature electronics are operating while influenced by
vibration and movement, so even well secured and tightened electrical connections can work loose over
time. If for example your heated-bed connection worked loose at the AMPS it can spark and burn the
plastic housing. A worse example would be your hot-end thermistor working loose, causing a runaway
hot-end temperature which would only stop heating (>500c) after burning through the electrical
connection. You should regularly check your electrical connections for signs of working loose or
excessive heat (especially around the high current AMPS connections). Your AMPS fan should also
be checked that it is putting sufficient airflow on these connections.
Hot-End Maintenance : Your MK8 hot-end (in fact any hot-end) is a high maintenance component, to
keep it running safely and producing high quality prints it should be regularly checked and serviced.
You will need to learn to strip down, clean and re-assemble your MK8 with a new barrel/nozzle which
should be done as a rough guide between 1 or 2 kilos of PLA. Here we completely service our hot-ends
after every single kilo reel of PLA to keep print quality high as towards the end of a second kilo reel you
will see print quality visibly degrade. Apart from print quality, safety is also a big factor as the hot-end is
the biggest fire risk on your EP AP if run un-checked and un-serviced.
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1. Y-AXIS Frame
1.1 Y-AXIS Long Sections
First take the two 350mm M8 smooth rods and slot one LM8UU bearing onto one, and two LM8UU bearings
onto the other. Next slot the four Y-Corners onto the ends of the 380mm M10 Threaded ods, then slot the two
350mm M8 Smooth ods (with bearings) into the Y-Corner top slots, finally screw on and loosely hand tighten
the M10 nuts (and washers). The smooth rods need to be pushed well into the end corner slots .. but its not absolutely
essential they are flush with the back of the slot, they aren't going to move around once its all assembled.
Fig 1.1 (Y-Axis Long Sections) :
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1.2 Y-Axis Rear Section (Motor)
Fig 1.2 Parts:
Firstly wire up a round shaft motor with about a 10cm extension length of wire & dupont connector. (see appendix A,
motor wiring). Next slot the GT2 timing pulley onto the motor shaft with the teeth close to the motor and gently tighten
the grub screws (see Fig 1.2a). Next mount the endstop into the endstop mount (it will only fit in one way round) and
secure with 2 16mm M3 bolts+nuts (Fig 1.2a). Next mount the Motor onto the Y Endstop / Motor Mount using 3 x 16mm
M3 bolts with M3 washers. Make sure the wires from the motor are orientated at the back of the motor mount and the
motor is mounted on the right hand side of the mount (Fig 1.2a).
Fig 1.2a:
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Next mount the motor assembly onto the two M8 threaded rods with the GT2 timing pulley teeth in the centre
and the motor wires feeding out through the back of the two rods (Fig 1.2b). Just hand tighten the M8 nuts at
this stage.
Fig 1.2b:
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1.3 Y-Axis Front Section (Idler)
Secure the idler onto one of the M8 threaded rods, dead center (loosely hand tighten) see Fig 1.3a If the idler pulley isn't
pre assembled see appendix B (idler pulleys).
Fig 1.3a
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1.4 Y-Axis Lo er Frame Completed
To complete the lower frame slot the completed end sections into the Y-corners of the completed long side
sections. Leave about 1 or 2 mm of M8 thread protruding and just loosely hand tighten the M8 nuts for now,
they will be adjusted later when the build plate is mounted (section 3). With the idler at the front (top M8
threaded rod) , motor at the back, single bearing on the left hand smooth rod and two bearings on the right hand
smooth rod (Fig 1.4a). The 30mm centre 'frame grip' washer on the M10 threaded rod should be 10cm with a MK8
extruder (or 11cm with a J-Head/Gregs Wade Extruder) from the flat inner of the rear Y-corner (Fig 1.4b).
Fig 1.4a:
Fig 1.4b:
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2. Z-AXIS Frame
Fig 2.0 parts:
2.1 Z-Axis Frame Mounting
Secure the frame between the two large 30mm M10 washers, then hand tighten on each side leaving approx
10cm between the flat rear of the Y-Corner and the rear of the frame (Fig 2.1a).
Fig 2.1a:
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Once the lower frame in securely seated (press down) in the M10 notches of the Aluminium frame, and the
measurement (about 10cm) is the same on each side and the 4 M10 bolts are hand tightened then flip the frame
onto its side and firmly tighten using two M10 spanners (or adjustable spanners), Fig 2.1c. These nuts need to
be tight as they prevent forward/backward wobble of the frame while printing.
Fig 2.1c:
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2.2 Z-Axis Top/Bottom mounts (PLA)
Next bolt the Z-Top/Bottom PLA parts to the frame using 3 x M3 bolts/nuts/washers (Z-bottom Fig 2.2a) and 2
x M3 bolts/nuts/washers (z-top Fig 2.2b). M6 od holders (holes) on the outer edge, tighten M3 bolts/nuts
firmly but not too firm, these parts tend to stay secure and its best not to stress the PLA by over tightening.
Fig 2.2a:
Fig 2.2b:
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2.3 Z-Axis Motors & End-stop
Mount the two motors with wires facing the back, the right side motor needs a 45cm extension and the left side
motor no extension (just the dupont 4 pin connector) .. see appendix A Motor Wiring. While mounting the left
side motor include the end-stop mount using the M3 bolts & washers (Fig 2.3a). Be careful mounting motors
you really don't want to strip any of the motor threads! The M3 bolts should screw in smoothly and tighten after
about 4-5 mm .. that's not a huge amount of thread but you can tighten them firmly (but carefully). ight side
motor mount with 3 x M3 bolts & washers (Fig 2.3b).
Fig 2.3a:
Fig 2.3b:
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3. Build late & Heated Bed
3.1 Build Plate Mounting
Firstly attach the Y-beltholder to the underneath of the waterjetcut Aluminium build plate, open side facing
towards the two bearing slots (Fig 3.1a).
Fig 3.1a:
Next mount the build plate onto the 3 bearings of the Y axis smooth rods, using cable ties secured as tightly as
possible – the bearings should be held firm or your build plate will flex (Fig 3.1b).
Fig 3.1b:
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Now is the time to tighten up all the nuts on the Y-axis, while ensuring the build plate slides freely on the
smooth rods and is aligned straight, adjusting the nut positions slightly if necessary. Also make sure the motor
end-stop isn't slanting forwards or backwards but sitting up straight so that the build plate will make square
contact with it. Finally make sure all M8 and M10 nuts are firmly tightened (but not too firmly). Its worth
spending some time on this tightening stage to get it right before moving to the next steps.
3.2 Y-axis belt
Cut approx 61cm of GT2 Timing Belt and feed through the idler pulley and around the motor pulley, slotting
both ends into the teeth of the Y-beltholder ,then screw in the M3 belt clamp bolts and clamp down lightly (it
does not need to be clamped very hard, this part can break). Make sure the idler is pushed fully forward so that
you can tighten the belt later and tilt the frame onto its side to get good access (Fig 3.2a)
Fig 3.2a:
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Next tighten the belt by slacking/positioning/re-tightening the idler between the M8 nuts (Fig 3.2b). The belt
should be tight enough to be nice and springy .. but not extremely tight as that can stress the motor.
Fig 3.2b:
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3.3 Heated Bed Mounting
After all the nuts on the Y-axis are tightened, mount the Heated Bed onto the Aluminium Build Plate, using the
25mm M3 bolts & washers secured with the 4 M3 nylock nuts. We use a fixed mounted front on the heated bed
as it greatly simplifies bed levelling as well as increasing stability and reliability, without compromising on
accuracy. Also firmly cable tie the smooth rods into the Y-corners at this stage (not shown in the Figs).
Mount as follows :
Front : M3 Bolt head, steel washers, heated bed, fibre washer, nylon spacer, steel washer, Aluminium build
plate,M3 nylock nut.
ear : M3 Bolt head,steel washers, heated bed, steel washer, spring, steel washer, Aluminium build plate, M3
nylock nut.
Fig 3.3a:
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4. Ramps Mounting
Now is a good time to mount the amps board while access to the frame is easy before the X-axis goes on.
Unplug the power connector from the amps board (parts picture), it will be wired up later to the power supply
& always on fans.
4.1 Ramps mount
Clip the amps mount to the rear left of the frame and slot in the clamp bolt (but not tighten) , Fig 4.1a
Fig 4.1a:
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Next slide the Arduino/ amps into to the amps mount from the top of the mount (Fig 4.1b), power connectors
facing down. Now tighten the clamping bolt (Not too tight)
Fig 4.1b:
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4.2 Ramps Y & Z Wiring
Now is a good time to deal with the wiring for the Y and Z axis. Firstly secure the wiring out of the way of the
build plate by cable tieing onto the M10 and M8 threaded rods (Fig 4.2b). Then connect the Z-axis motors to
the top right twin 4pin connectors and the Y-axis motor to the middle right 4pin connector (red wire up).
Finally Connect the Z-endstop and Y-endstop wires to the left two pins of the 18 pin bank of pins at the top left.
The 18 pin bank of pins is in 6 rows of 3, if the bottom row is row 1 and the top row is row 6, connect the Y-
axis to row 3 and the Z-axis to row 5 (X-axis goes on row 1), see Fig 4.2c. (Note: An older style ramps mount
is shown here with 2 pin endstop connectors, this makes no difference the connection is still on the left two pins
of the bank even if you have 3 pin connectors, normally the 3rd pin will have been disabled)
Note: If you connect your endstops to the incorrect pins you will destroy your electronics the moment an
endstop is triggered (you will be able to smell your Mega 2560 burning). It will save time and money re-
reading and triple checking your endstop connections before powering up, take as long as necessary until
your 100% sure your connected correctly. Looking at the AMPS from the rear of the machine , the 18
pin bank, 6 rows of 3 pins. Your endstops connect to the left hand two pins (see 4.2a and 4.2c showing the
connectors attached to the left two pins). If your end-stop connector housings are 3 pin, the third pin will
be disabled. See also the AMPS wiring diagram in section 8, as well as the AMPS 1.4 wiki online.
Fig 4.2a
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