RepRapPro Tricolour x axis assembly
Introduction | Frame assembly | Y axis assembly | X axis assembly | Z axis assembly | Heated bed assembly | Extruder drive assembly | Hot end assembly | Wiring | Power supply | Commissioning | Printing | Multi‑colour/multi‑materials | Colour Printing - Slic3r | Colour Printing - RepRapPro Slicer | Maintenance | Troubleshooting | Improvements
| A notice about these instructions! |
|
These instructions are open to editing by everyone and anyone. |
Contents
Goal
By the end of this stage, your X-axis should look like this:
Tools
You will need the following tools
- M3 Allen key
- Long-nosed pliers
- Tweezers
Step 1: X carriage assembly
| |
| Item | Quantity |
| 428mm smooth X rods | 2 |
| Printed X motor bracket | 1 |
| Printed X idler bracket | 1 |
| Printed X idler cover | 1 |
| 623 bearing (10mm diameter) | 1 |
| M3 washers | 2 |
| M3x20mm cap screws | 3 |
| LM8UU linear bearings | 3 |
| M3 nuts | 3 |
The Carriage
Begin by assembling the Y Idler Bracket. Take one M3x20 capscrew and a corresponding washer and insert it through the hole in the centre of the part as shown below. Then insert this assembly through the 623 idler bearing, through the cover and secure with a M3 nut and washer:
Next insert two M3 washers into the slots on the back of the idler bracket. These are intentionally a tight fit, so you may need to use a long-nosed pliers in order to grip them. The nuts should go in sufficiently far that the holes of the M3 nuts line up with the small holes in the end of the idler bracket.
Next begin to assemble the axis. Take the 428mm smooth rods and insert these into the large holes in the end of the X idler bracket. Then proceed to slide the linear bearings onto the smooth rods. Note the orientation of the bearings, when looking at the top/complex side of the idler bracket, two bearings go on the top bar with the one remaining bearing on the bottom bar as shown:
Ensure the rods are completely inserted into the X idler bracket, then insert the free end of the rods into the X motor bracket:
Put nuts and washers on the ends of the hex-headed screws.
Don't do these up tight. These screws allow you to adjust the relative heights of multiple extruders in the carriage.
Fit the belt clamps with screws nuts and washers.
Start by sinking the nuts into their recesses. You can do this most easily by pulling them through with a screw with a washer under its head. Make sure as you tighten the screw that the hexagon of the nut is aligned with its hexagonal hole.
The belt-gripping indentations on the clamps face the vertical pillars.
Fit the tensioning screw using the nylock nut as shown:
Step 2: Main X axis assembly
| |
| Item | Quantity |
| Printed X end (motor) | 1 |
| Printed X end (idler) | 1 |
| 428mm smooth 8mm rods (X) | 2 |
| 8mm IGUS bearings | 4 |
| M3 nylock nuts | 2 |
| M3x16mm screws | 2 |
Please note that there is an improvement to the design of the X motor end. It looks like this:
Start by fitting the IGUS bearing inserts to both ends:
You can curl them up so their ends overlap to insert them. Be careful.
Check their internal diameter by running one of the 8mm rods down them. If the rod is too tight (don't force it) put a 9.5mm drill bit shank in a vice, take the bearing inserts out, and slide the printed part over the drill to clean out the hole. Again be careful - you don't want to remove too much material and make a sloppy fit.
Repeat this process until the rod just fits and slides smoothly. It should not wobble from side to side.
With the tweezers fit the nylock nuts into their recesses in the idler end:
Pull the nylock nuts into their recesses with a screw if needs be.
Screw the two screws in by just three or four turns. Slide the smooth rods in so that they abut the screws and nuts.
Put the X carriage on the rods. Make sure to get it the way round shown in the picture.
Insert the rods into bearings while watching the opposite end of each bearing to make sure none of its balls get pushed out of their tracks. If they do, they can be reseated by pressing them back into the track with the tip of a chopstick. As a precaution, cover the area under your work with a tissue to catch any balls that might fall out.
Put the motor end printed part on the other ends of the rods. Make sure they slide right up to the closed ends of their holes:
Step 3: Fit the X motor
| |
| Item | Quantity |
| NEMA 17 motor | 1 |
| M3x10mm screws | 3 |
| M3 washers | 3 |
| Toothed belt pulley | 1 |
| M3 x 10mm set screw | 1 |
Later versions of Mendel have printed toothed-belt pulleys like this:
These simply push-fit onto the motor shaft - see below.
Use the screws and washers to mount the motor:
If you have a moulded pulley, screw the set screw into the toothed-belt pulley. Take care not to cross the threads - the plastic is not hard. Screw it in far enough to project into the hole down the middle, then back it off so it is no longer projecting. Blow any displaced pieces of plastic from the central hole. Put the pulley on the motor shaft with its hub outermost, as shown. Use the toothed belt to get it roughly the right distance along the shaft. Align the set screw with the flat on the shaft, and tighten it. Do not over tighten it - the pulley has an internal embedded nut, and over tightening will cause this to fracture the pulley.
If you have a printed pulley push it onto the shaft. It should be a tight fit, and you may have to tap it into place. Use a soft hammer, or a wood block. If you place an M8 nut against the pulley, you can tap the nut to place the pulley. Support the motor shaft, not the motor body, from the other end as you tap. You can secure it with a drop of superglue if you like (make sure the shaft is completely free of grease). Take care that no glue gets near the shaft's entry to the motor.
Step 4: The X belt idler
| |
| Item | Quantity |
| 35mm M8 threaded rod | 1 |
| M8 nuts | 2 |
| M8 mudguard washer | 1 |
| 8mm bearing | 1 |
| M8 washers | 3 |
Fit the idler:
From the right the sequence goes:
- Nut
- Mudguard washer
- Washer
- Bearing
- Washer
- Printed idler end
- Washer
- Nut
