The Anet A8 is an extremely popular 3D printer because of its affordability and modifiability. This Printer comes usually as a kit which is easy and fun to put together. Its design is based on the Prusa i3 printer as a cheaper alternative and as such an excellent kit for amateurs who are eager to learn about FDM printing. Many upgrades are readily available on the market as DIY projects or ready to buy. The print quality is somewhat OK, which depends on the actual requirements. I’m using this machine to create prototypes for many of my projects which unfortunately sometimes not quite reach the necessary quality for the purpose. Many of my original printers’ parts have been already replaced to archive that little bit higher quality level.

In this tutorial I’ll show you how to assemble the latest upgrade for my Anet A8. The I-Bot uses the BONDTECH BMG extruder in conjunction with a E3D V6 All-Metal HotEnd. As drive is a MOONS NEMA17 MS17HD5P4100 stepper motor used and the cooling fans are two NOCTUA NF-A4x10 FLX.

There’re sure some cheaper alternatives out there to realize this product, but the goal here is to use high quality components to prevent eventual possible quality contamination of the final product.

Step 1: The Parts...

Here is the list with the parts necessary to build the I-Bot Extruder:

1 set - of printed plastic parts
- you can get the design files here
- print them yourself or have somebody do it for you
1 pcs - BONDTECH BMG
2 pcs - 40x40x10 NOCTURA Fan NF-A4x10 FLX
1 pcs - 2-Phase stepper motor MOONS MS17HD5P4100
4 pcs - Drylin bearings IGUS RJ4JP-01-08
1 pcs - E3D V6 All-Metal HotEnd
3 pcs - 8 mm cable clip
- I got those out of an assortment which I bought at Harbor Fright
3 pcs - Tapered Heat-Set Inserts for Plastic
- Brass, M2 x 0.40 mm Thread Size, 4.800 mm Installed Length - McMASTER CARR
18 pcs - Tapered Heat-Set Inserts for Plastic
- Brass, M2.5 x 0.45 mm Thread Size, 3.4 mm Installed Length - McMASTER CARR
8 pcs - Tapered Heat-Set Inserts for Plastic
- Brass, M3 x 0.50 mm Thread Size, 3.800 mm Installed Length - McMASTER CARR

All screws I used came out of this two boxes from AMAZON: AssortmentA and AssortmentB

3 pcs - M2 x 10mm socket head screw
6 pcs - M2.5 x 10mm socket head screw
12 pcs - M2.5 x 16mm socket head screw
6 pcs - M3 x 20mm socket head screw
2 pcs - M3 x 30mm socket head screw
3 pcs - M2 washers
24 pcs - M3 washers

Make sure the plastic parts are cleaned up as good as possible if necessary to ensure proper fitting. I used PETG as printing material because of its mechanical properties. The printer settings probably differ from device to device, I used the following settings:

bed temperature 60° C / 70° C for the first layer
print temperature 235° C / 240° C for the first layer
slicer software is Slic3R
nozzle 0.4 mm
print bed - glass with BuildTak

Step 2: Heat Sink Cooling...

The E3D V6 ALL-METAL hot end has a heat sink which need to be cooled for proper working of the device. This is done with a snap on air duct which consists of the following parts:

1 pcs - AirDuct A1 Cover
1 pcs - AirDuct_A1
1 pcs - NF-A4x10 FLX Fan
4 pcs - M3 x 20mm socket head screw
4 pcs - M3 washers
4 pcs - Tapered Heat-Set Inserts for Plastic
- Brass, M3 x 0.50 mm Thread Size, 3.800 mm Installed Length

Please make sure the fan is mounted in such way that the air is blown into the air duct. The most fans have some kind of markings on the side to show the direction of flow. If there is no such marking, the most fans blowing air from the open end to the side where the fan motor is mounted. In cases where this is not clear the flow orientation must be tested by powering up the fan briefly.

The four Heat-Set inserts have to be installed in the holes of the AirDuct_A1 part from the side where the fan is going to be mounted.

I'll not going into details of how to install those inserts in this tutorial, but here is a good one from Randy Cox on his YouTube channel.

The screws with washers are inserted from the side of the "AirDuct_A1 Cover" through the holes in the fan into the thread inserts.

Be careful tightening the screws because the thread inserts don't withstand a lot of torque.

Step 3: Extruder Bracket Preparation...

Small cable clips are used to help with the wiring of the device. Here are the parts for that installation:

1 pcs - Extruder Bracket M002
3 pcs - 8 mm cable clip
3 pcs - M2 x 10mm socket head screw
3 pcs - M2 washers
3 pcs - Tapered Heat-Set Inserts for Plastic
- Brass, M2 x 0.40 mm Thread Size, 4.800 mm Installed Length

I got my cable clips out of an assortment box which is probably not necessary the only source of those. A ruler can be used to identify the correct size of the clips as shown in the picture. Those clips are not necessary for a correct functioning of the extruder, the wiring can be don different ways.

The Heat-Set inserts have to be installed into the correct holes, see picture. The 3 cable clips are mounted using the M2 screws with washers.

Be careful tightening the screws because the thread inserts don't withstand a lot of torque.

Step 4: Extruder Bracket - BB-Base Installation...

Before we can proceed with anything else, the Bearing-Bracket Base has to be mounted to the Extruder-Bracket. Those parts will fit only one way together, but check the pictures to prevent eventually confusion with the mounting direction. The parts are used for this step are as follows:

1 pcs - Extruder Bracket M002 with or without the cable clips installed
1 pcs - BB-Base
6 pcs - M2.5 x 10mm socket head screw
6 pcs - M3 washer
18 pcs Tapered Heat-Set Inserts for Plastic
- Brass, M2.5 x 0.45 mm Thread Size, 3.4 mm Installed Length

Insert all 18 heat-set inserts from the back side of the BB-Base.

I would like to direct you at this point to the video from Randy Cox on his YouTube channel about working with heat-set inserts.

Use M2.5 screws with washers to fasten the two parts. The M3 washers are a tight fit which depends on the print and might have to be pushed in with the help of some proper tool.

Be careful tightening the screws because the thread inserts don't withstand a lot of torque.

Step 5: Part Cooling...

A proper part cooling is almost as important as any other parameter in the printing process. Therefore a special designed AirDuckt_A2 is used to provide an optimum part cooling. The following parts building this critical component:

1 pcs - Extruder Bracket M002
- ENSURE STEP 04 IS PROPERLY DONE BEFORE YOU PROCEED
1 pcs - AirDuct_A2
1 pcs - AirDuct A2 Cover
1 pcs - NF-A4x10 FLX Fan
2 pcs - M3 x 20mm socket head screw
2 pcs - M3 x 30mm socket head screw
2 pcs - M3 washers
4 pcs - Tapered Heat-Set Inserts for Plastic
Brass, M3 x 0.50 mm Thread Size, 3.800 mm Installed Length

The four Heat-Set inserts have to be installed in the holes of the AirDuct_A2 part from the side where the Extruder Bracket is going to be.

This installation is kind of a 2-Step procedure. The 2 M3 x 20mm srews without washers have to be mounted first before the 2 M3 x 30mm srews with washers which holding the fan cover can be installed.

Be careful tightening the screws because the thread inserts don't withstand a lot of torque.

Step 6: BONDTECH BMG Installation...

The BONDTECH BMG with the E3D hot end installation is straight forward and can be seen in the pictures. However, it's the most important step and should not be underestimated.

The assembly of the E3D V6 ALL-METAL hot end is detailed explained in this video from Thomas Sanladerer on his YouTube channel. This guy has a lot of experience with 3D printing and you can find some awesome videos there.

The same is to say about the correct assembly of the BONDTECH BMG itself. You can find a very good tutorial on the BONDTECH YouTube channel about that.

The parts used for this step are:

1 pcs - BondTech BMG
1 pcs - 2-Phase stepper motor MOONS MS17HD5P4100
1 pcs - E3D V6 All-Metal HotEnd

Step 7: Linear Bearing Installation...

DryLin bearings are used to provide smooth movement along the X-Axis. Those bearings are very precise, noiseless and maintenance free.

The parts for this step are:

1 pcs - BB-Cover T
- Bearing Bracket Cover Top
1 pcs - BB-Cover B
- Bearing Bracket Cover Bottom
4 pcs - Drylin bearings IGUS RJ4JP-01-08
12 pcs - M2.5 x 16mm socket head screw
12 pcs - M3 washer

The two covers are non-symmetrical and can't be installed at the wrong place. The bottom cover "BB-Cover B" has a little grove which will fit to the bottom part of the "BB-Base" and the top cover "BB-Cover T" don't have this grove which will makes it impossible to install it on the bottom side of the "BB-Base".

Before the cover are mounted using the M2.5 screws with M3 washers, the DryLin bearings have to be places onto the base bracket as pictured. The screws can be tightened, but should allow for some play for an easier installation on the actual X-Axis.

You need to keep in mind that also here the threads are just heat-set inserts and not meant to hold a lot of torque.

Step 8: Finally Finished...

From here on the I-Bot Extruder is completed and ready for installation onto the X-Axis, which will be explained in another tutorial.

A few more things which have to be mentioned to make this tutorial complete.

You'll find 2 holes in the plastic above the stepper motor. those holes can be used to hold a small Zip-Ty for the cable coming from the device.

The linear guide rods on my Anet A8 have a distance of 46mm. I've seen versions of that particular printer with different measurements, please keep this in mind if you attempt to build the I-Bot Extruder for your printer.

All used parts can be replaced by cheaper after marked versions and the I-Bot Extruder will probably still work just fine. My goal with this project was to use high quality products to support a high quality end product.