(Applies to all Bukobot v1 (2012) models unless specifically noted)
To check the X axis, press both ends of the X axis down on their UHMW nuts to make sure they haven't lifted during transport, then gently tighten the small screw on each one.
Measure both ends of the X axis rods and make sure they are the same distance from the base of the frame. To adjust, grip the lead screw couplers and turn them by hand while holding the opposite motor still (one motor may generate enough current to cause the other to turn). You can use a ruler/calipers or just lower them onto any sturdy and straight object until it just touches the smooth rods when placed under each end.
Check Synchromesh cables between the two pulleys on the X & Y axis and pluck them gently, they should be tight enough to feel like a guitar string but not too tight to stretch or bend any plastic parts.
If they don’t feel tight, locate the tensioner on the X carriage (might be a orange lever) and slightly loosen the two screws. Turn the tensioner to pull the cable tighter, then tighten the screws again.
To adjust the Y axis Synchromesh cable under the platform, tighten the screw under the platform, facing the front, until the cable is more tense like a guitar string.
[To be written soon]
Adjust the Z endstop all the way up by turning the thumbscrew below it (loosen spring).
By hand, move the nozzle to the center, and the platform all the way forward but make sure the nozzle in a few millimeters within the glass on the platform.
Connect the USB cable and power on the Bukobot, establish a connection with the host program (Repetier Host or Pronterface).
Find the reset button near the USB connector be ready to push it so that you can stop the machine in the rare case of the endstop fails or if it’s too low. (Pulling AC power isn't sufficient as there is enough energy stored in the power supply to keep the motor running for a few seconds)
Raise the Z axis with the host software a few millimeters, away from the end stop to make sure it’s working (Note: At first start you can only go up or positive on the Z axis), then click “Home Z” in your host software and test the Z endstop by manually tapping it twice while the axis is moving down. If it does not function, reset the printer and turn it off, then check the wiring from the switch to the motherboard before continuing.
Click “Home Z” again, and the Z axis should move down, touching the endstop before the nozzle touches the platform, move back up a few millimeters and move more slowly back down to the endstop. If the nozzle touches the platform first, press the reset button to stop it, then move the Z axis up and adjust the endstop higher before trying again.
Once the endstop stops the extruder above the platform, adjust it down with the thumb wheel a bit and press “Home Z” again. Repeat until the nozzle barely touches the platform without pushing it down. You should be able to slide a piece of paper under the nozzle and feel only a slight resistance.
Lower the front part of the platform by tightening the two thumb wheels in the front of the platform, then move the platform and extruder nozzle so that the nozzle is over the front right corner of the glass.
Loosen the thumb wheel until the nozzle just touches the platform, and you can slide a piece of paper under the nozzle with slight resistance.
Repeat this process on the front left corner and then again on the right to make sure they are both equal.
The nozzle should now move freely just over the surface of the whole platform. If it does not, or a gap appears between the nozzle and platform in one area, repeat the Z endstop adjustment first and then try the platform leveling procedures.
Note: The are two different extruder body models for the Bukobot, the “Birdstruder” and the “Bukostruder” but the basics apply to most of them. Please note the differences.
In your host software, move the Z axis up to 20mm or more so that there is empty space under the nozzle.
Birdstruder: Release the extruder idler latch by turning the cam lock (shaped like a bird's head) and lifting it free, then rotate the idler down on its hinge.
Bukostruder: [to be added]
Insert the end of your filament through the small hole or slot at the top of the extruder. It should come out at the filament drive gear and pass into the second hole below it. Continue sliding the filament down as far as possible until it stops.
Birdstruder: Close and re-lock the idler, making sure that it is tight. When you pull the cam lock to compress the spring, it should just slip over the slot in the idler block in the disengaged position. If it is loose, tighten the nut on the opposite end of the M4 screw across the top of the extruder. Turn the cam lock 180 degrees to engage it.
Bukostruder: [to be added]
In the host software, set the extruder to the appropriate temperature for your plastic. For the included Diamond Age PLA, this is between 175-190c, for normal ABS use about 210-230c.
Once the extruder has reached its target temperature, put a mark with a sharpie at about 10mm from the extruder block. Then use the software to extrude 50mm of filament at about 80mm/minute to prime the extruder. Watch the mark to make sure that the filament is moving. It should move down into the extruder block. If it moves, but no filament comes out, extrude another 20mm until plastic begins to flow out of the nozzle. If the plastic that comes out is the wrong color, it maybe left-over plastic from previous testing or use, and you will need to continue to extrude until the color has changed completely to purge the nozzle.
Note: Switching from PLA or ABS or vise versa
If you want to use a material with a different melting temperature, you will have to do this at the highest of the two temperatures until the nozzle has been completely purged of the previous material.
The Bukobot has endstops for all axis (X,Y,Z) so before printing, always check that you are in the home position and your start code also contains any homing commands.