BotMill's Blog

• X-Axis
  • Carriage
  • Idler Bracket
  • Vert Bearing 180
  • Vert Bearing 360
  • Motor Bracket
  • X-Axis Final Assembly



So you have a 3D Printer and now you want to print that prototype you’ve been thinking about for so long.

Here are a couple of ways to take your idea and turn it in to a perfectly layered 3D plastic object:

1. 3D Scanner

We can send someone out to you to scan your object. The 3D Scanner will scan your object. After the file most likely needs cleanup and then GCODE generation before sending to the 3D printer.

2. 3D CAD Designer

Simply contact us regarding our CAD design services. Our 3D CAD Designers will guide you along the way with your sketch / drawing in order to create a 3D file with perfect GCODE.

3. 3D Modeling Program

A good free 3D Modeling Program we recommend is Google Sketchup. You can create anything you want with this program. Also, very easy to create 3D text.

These days, as more and more people learn for the first time about 3D printing, we receive many questions regarding:

How do I take my 3D CAD file and send it to your 3D printer?

Well, here it goes:

• First, you will need to check if it saved in STL format. If it isn’t, please use a conversion software and follow up with a clean-up software of your choice.
• Use Skeinforge or Repsnapper to convert your file to GCODE.
  • Skeinforge: For advance users. This program doesn’t send the file to the printer directly, instead it’s a sophisticated GCODE generator. Many people that have bought BotMill 3D Printers are now using them with this program and printing (what looks to me) like near commercial quality plastic pieces. After GCODE is generated with this program, use RepSnapper to send the file to your printer.
  • RepSnapper: This program is full circle. Not only is it speedy fast with it’s GCODE generator, but you can also send the file directly to your printer. One downside is that the GCODE generator is not as sophisticated “yet” as Skeinforge.
• Use RepSnapper to send your file to your printer
  • Connect your printer to the correct port. “click connect”
  • Turn on heater. Make sure your printer has been warm for at least 5-10 minutes before printing.
  • Load GCODE
  • Position object on “virtual” board
  • Test extrusion before printing any 3D plastic piece
  • Click “Print” in top tab

That’s it! Once your object has finished to print, your extruder should return back to it’s home position (right above the aluminum purge plate).

Happy 3D Printer Printing – 3D Revolution!

So, you’ve finished building your Y-Axis assemblies for your BotMill Axis 2.1, and even have mounted them on it’s aluminum “spider”, ready to move on to next step right? WRONG. Here’s a hint from the BotMill team: do NOT forget to test the smooth rods through the assemblies! they must be centered. alignment is crucial. Remember, there will be a bed attached on top of this component—so, proper calibration of the bed is contingent on aligned rods.

Lately we at BotMill have been stressing keeping things loose. while that’s true in certain situations (see our “building the perfect X-axis” blog post from the other day), you can actually tighten the Y-Axis assemblies properly WITH the smooth rods going through the bearings. Simply slide the rods out once configured. This will ensure correct bed alignment down the road when you complete the machine.

Happy printing and stay tuned for more tips from the Calibration files!

The other day we gave a tip on keeping the z-bar frame clamps loose when building your Axis 2.1. Well, here’s another hint from the BotMill production team: perfect construction of an X-Axis can be achieved without hassle if you refrain from tightening certain components until the very end.

- Motor Bracket
leave the m3 nylock nut on the belt clamp loose, you can tighten them once you slide the smooth rods into place THEN tighten them to ensure snug fitment and good alignment

- Vert Bearing 360
The only thing you want to leave loose here are the (4) screws on the M4 clamps. Again, this will enable you to easily slide on the smooth rods and help you position it in it’s correct spot.

- Carriage
It is very simple to attach the belt to the X-Axis if you leave the belt clamp M4x40 screws loose when building the carriage, that way when your ready to attach the belt you can pull back the actual belt clamp piece and slide the belt behind the belt clamp. Then just tighten it!

- Vert Bearing 180
Notice a pattern here? follow instructions for it’s sibling to the right, the Vert bearing 360

- Idler Bracket
As with the motor bracket, leave the M3 nylocks on the belt clamp loose. We here at BotMill have also found ourselves keeping the X180-Z-bearing plate(s) loosely attached to the end bracket until final assembly.

Following these simple steps should ensure construction of a perfect X-Axis. Stay tuned for more tips and tricks.

When constructing the frame, it is important to keep the two Z-bar frame clamp assemblies loose.  When your ready to slide the “smooth” z-bar through the Z/X Axes and finally the Z-bar frame clamp, you might have to slide the clamp assembly to the left or right. This is much more feasible with a loose assembly. Then once the smooth rods are positioned properly, you can tighten the frame clamps and continue with the build.

A crucial step that we field questions on is securing the Z-bars when constructing the frame. A reminder to all building: Make sure you use three M4 x 12 screws to secure the bearing in the leadscrew base! Fasten with nylocks (make sure you use washers also), and your Z bars are fastened, ensuring a proper fitment and smooth movement. hope this helps!

Now that we have completed all assemblies required, we can go ahead and put together the X-Axis. First, lets summarize the assemblies we have prepared to get us to this point:

- Carriage (completed with extruder, see extruder)
- Idler Bracket
- Vert Bearing 180
- Vert Bearing 360
- Motor Bracket

The order that the assemblies are attached to the X-Axis smooth rods, when facing the front of the machine, from left to right, is as follows:

Motor Bracket-spacers-Vert Bearing 360—–Carriage/Extruder—–Vert Bearing 180-Idler

You may install it however you please, but we like to begin with the Motor Bracket. Be sure to insert the smooth rods so that they are flush with the belt clamp pieces. Repeat this on the other end for the belt clamps on the idler bracket as well. Be sure not to forget the spacers that go in between the Vert Bearing 360 and the motor bracket. Once all the assemblies are on, go ahead and tighten anything that it still loose, one by one. Here are is a breakdown of important items we have left loose on each assembly to ensure proper installation:

Motor Bracket – 4 M3 Nylock nuts on the X-Bar M3 clamp pieces (outer screws), 4 M3x20 screws attached to the motor (motor screws might already be tightened all the way depending on how you’ve gone about it)
Spacers – n/a
Vert bearing 360 – 4 M4x40 screws (2 for each clamp piece) on the X-bar M4 Clamp pieces
Carriage/Extruder – n/a
Vert Bearing 180- 4 M4x40 screws (2 for each clamp piece) on the X-bar M4 Clamp pieces
Idler bracket – 4 M3 nylock nuts on the X-Bar M3 clamp pieces (inner, outer screws)

Belt Installation

Installing the belt can be a stress-free process if you adhere to the following procedure. First, wrap the belt around the entire axis, ensuring that the teeth of the belt are wrapped around the gear, and the smooth sides are wrapped around the four (4) bearings on the motor bracket, and two (2) bearings on the idler bracket. Slide the belt behind the two belt clamp pieces on the carriage, which should already have two M4x40 screws (with washers) already installed. Once the belt is inserted behind the clamp, insert two more M4x40 screws (with washers), and pull the belt, forming a small loop. While pulling the loop, which will tension the belt, use an M4 hex key to tighten the screws. Note that you trapped M4 nuts in each hole on the carriage, so it will tighten properly. The result will be wonderfully tightened belt. Be sure not to tighten the screws too much. A good way to test if the belt has successfully been installed is to turn the gear in each direction. If installed properly, a single turn of the gear (called, a “step”) will result in the X-Axis moving one exact step as well. If it is too lose, the X-Axis will move more than just one step. If too tight, it will not move at all. Using these hints will ensure perfect X-Axis. This concludes construction of the X-Axis.

The X-Axis is what conducts all lateral (left/right) movement of the 3D Printer. It also houses the extruder, which is mounted on the carriage piece.

A relatively straightforward assembly, start by taking the gear for the X-Axis and mounting it on the motor shaft. We suggest lightly tapping a hammer and using something as a barrier between the hammer itself and the gear. You can use anything you’d like, however we suggest a pair of needle-nose pliers. For this gear, you want to drive it all the way down the shaft, so the belt will be as closely lined up to the bearings as possible. This will limit friction once the belt is on and ensure smooth lateral movement of the X-Axis. Set aside.
It is now time to prepare the X-End Bracket for assembly. Start by installing the four X Bar M3 clamp pieces. You want to fasten the clamps by using M3x20 screws, fortified with washers and secured with M3 nylock nuts. Note that this is applied only to the outer holes, as the inner holes on the clamp pieces will be reserved for motor attachment. Be sure to keep the M3 nylock nuts loose, as in a short time you will be sliding the X-Axis smooth rods through them for final X-Axis construction. Once secured, you can go ahead and install the motor.
To install the motor, you want to make sure the wires that extend out of the motor are facing towards the back of the machine once built. . Secure the motor with four (4) M3x20 screws, being sure that all four screws are tightened into completely into the motor. Once that’s done, we can focus on the four bearings.
Use four (4) M4x16 screws on the outer perimeter of the X End Bracket to attach the bearings. The process is exactly the same as the X-Axis Idler bracket, however on the motor bracket will do this four times as opposed to twice for the Idler. The sequence is as follows: cap-screw head-washer-X End Bracket-washer-bearing-washer-M5 mudguard washer-M4 nylock nut. Be sure to tighten these fully. This completes construction of the X-Axis Motor Bracket.