TEVO Tornado Dual Extrusion: Beau's TL-Feeder Version

An easy way to upgrade your TEVO Tornado 3D Printer with dual extrusion for less than $50!

What to buy:

• TEVO Titan Extruder (without pancake stepper motor)
• NEMA 17 48 mm Stepper Motor
• Trianglelab TL-Feeder (Set 1)
• M5 55mm Screw
• M5 Nut
• Some Zip Ties (if you don't already have them)

What to print:

• Dual Extruder Mount
• Flexible Filament Mount (for PVA and flexible filament printing. Please see the very last step!)
• Bowden Tube Locking Clips (3 of them)

Model Example Credits:

• https://www.thingiverse.com/thing:948577 Christmas Tree (now with lamp base) by idig3d
• https://www.thingiverse.com/thing:1913982 Dual Draudi by BCN3D

Image credit to TriangleLabs

From the 2 meters of bowden tube included in the TL-Feeder Kit (4mm OD, 1.9 mm ID), cut a 5-6 inch section of tubing. Make sure to keep the cut as straight and clean as possible in order to reduce the risk of filament jamming.

This section of tubing will be called the hot tubing.

To prevent jamming, I highly recommend adding a slight bore to one end of the hot tubing in order to reduce jamming when the new filament enters from the TL-feeder.

I didn't actually have a bore tool bit on hand, so I searched around and found my old pocket knife sharpener rod and stuck it in my hand drill. Then I inserted it into the hot tubing and fired it up until the inner diameter became a little bigger.

(The bowden tubing above the green table is before the bore was made and the picture of the bowden tubing over the wood table is after a bore was made)

Cut two more sections of bowden tube about 300 mm in length. Do not use any of the bowden tubing from the TEVO Tornado kit. Only use bowden tubing the TL-Feeder kit (4 mm OD, 1.9 mm ID).

Remove the extruder stepper motor from its bracket. Carefully open one side of the 3D printed dual extruder mount (without breaking it) and slip the first stepper motor in. Repeat for the second stepper motor. Make sure the cable connectors will not be blocked. Screw the M5 screw into the middle hole. Compress the mount onto the stepper motors by tightening the nut onto the screw.

Remount into the original extruder's position as shown in the position and reassemble the titan extruder for both motors. Use the 3D printed spacer in-between the new stepper motor and Titan extruder.

Note: Fore better cable security, I mount the original extruder motor backward so that the cable connector is facing away from the control box. Then I mount the new extruder motor with the extruder facing the control box. See the second image.

(The CAD renderings show the titan extruder mounted upside down. Sorry!) ;)

These are a MUST! Put them in all 3 openings of the TL-Feeder. This will keep the bowden tubes secure and prevent them from falling out.

Tip: If you 3D print these at 75% the size in the Z-direction, these will fit in the other bowden couplers of the Tornado. Print normal size for the TL-Feeder. ;)

Turn the Tornado on and heat up the hot end to 200C. Unload any filament being used. Remove the stock bowden tube (see the link below to ruiraptor's tutorial). You may need to unscrew the bowden tube couplers from the hot end heatsink and loosen the extruder assembly. Rescrew and tighten.

Insert the two new ((300 mm) bowden tubes into the respective Titan extruders and TL-feeder spots. Make sure they go all the way in!!!

Insert the bored end of the hot tubing into the bottom of the Tl-feeder. Again, make sure it goes all the way in!!! Insert the other end of the hot tubing into the hot end. MAKE SURE IT GOES ALL THE WAY OR ELSE CLOGGING WILL OCCUR!!!

Turn off and unplug the printer.

This is the only wiring step in this setup!

Unplug the printer. UNPLUG!!! Not turn off!!!!!!!!! UNPLUG!!!!!!

Carefully open the control box (there are 6 screws total). Beneath the top of the control box over is the 3D printer mainboard.

Before performing the wiring, make sure that the new stepper motor cable's colored wires are in the same arrangement as the pre-connected stepper motor cables ON BOTH SIDES of the cable.

Plug one end of the new motor cable into the empty E1 port as shown in the picture. Loop the rest of the cable through the hole in the back of the control box. Using one or two zip ties, safely secure the new motor cable to the rest of the wires so that it does not interfere with the cooling fan.

Close the control box and re-insert the screws. Plug in the new motor cable into the new extruder motor. If you have any wire sheathing, use it.

Image credit to Qianman Tan, CEO of TEVO Inc.

Secure all of your dangling wires (especially the hot end wires) and bowden tubes with zip-ties. Clean up the workspace and make your work look all fancy!

Download the Arduino IDE onto your computer and open my attached firmware. Connect your computer to the Tornado control box and via USB and upload the new firmware to the Tornado.

Again, ruiraptor has a fantastic tutorial on how to install firmware on the Tornado.

Cold extruder moves and EEPROM are enabled in my firmware.

Note: If you would like to make your own firmware from a newer version of Marlin, here are the instructions I used: https://www.distechautomation.com/pages/pro-sys-guide#1.02

Open Cura 3 on your computer.

I use Cura 3, for slicing my prints. So if you use Simplify3D, IdeaMaker, Slic3r, or another slicer, you're on your own. Sorry.

On the top left bar hover over Settings. Go to Printer > Manage Printers...

Click the Add button under Printers in the new window that opens.

In the new window, select Custom FDM Printer, name it, and click Add Printer.

Setup the Printer Configuration with the proper X, Y, and Z axis lengths.

Heat Bed: Enabled

Extruders: 2

X min: 0

X max: 0

Y min : 0

Y max: 0

In the same window (Machine Settings), click on the Extruder 1 tab. Set nozzle X and Y offsets to 0.

This is where we will tell the printer to do everytime it switches between colors. There are different variations of this that can work. Here is what I use:

Extruder Start Code:

G92 E0 ;Reset extruder positioning
G1 E279 F10000 ;Extrude new filament to nozzle

G92 E0 ;Reset extruder positioning

Extruder End Code:

G92 E0 ;Reset extruder positioning
G1 E-5 F4500 ;Retract filament 5 mm

G1 X40 Y65 F4500 ;Move to filament change location

G92 E0 ;Reset extruder positioning

G1 E2 F10000 ;Extrude 2 filament 2 mm

G92 E0 ;Reset extruder positioning

G1 E-277 F5000 ;Retract filament to resting spot

G92 E0 ;Reset extruder positioning

You may want to mess around with this code. Different materials like different settings. A quick guide to the commands I used:

G1 X? Y? Z? E? F? Tells the printer which coordinates to move to. F is speed.

G92 X? Y? Z? E? Resets the current position to the values given. (Ex: X, Y, and Z will stay the same if you only change E)

A semicolon will void whatever is written for the rest of the line (for commenting).

Enter the start and end code for extruder 2. Then click Finish. You can change these settings anytime.

You'll notice that the right side of Cura looks different, in that instead of settings for one extruder, you now have options for two.

I find it helpful when slicing objects to have the extruders and filament as 2 different colors. I do this by just changing the material name. HIPS, for example, is blue.

You're almost done! Under the Custom Print Setup (the extruder doesn't matter, the following settings are linked to each other), go down to Dual Extrusion. Enable the option for the prime tower.

Scroll down and make sure that Wipe Inactive Nozzle on Prime Tower and Wipe Nozzle After Switch are both enabled.

The prime tower, or as others call it, the purge tower, is a printed block next to the actual print that is used to purge the new filament being printed. For example, if I start by printing red and switch to blue, some of the plastic will still look red because the of the remnants of the plastic left in the nozzle. The prime tower is what is used to get all (or most) of the red color out until I have a sharp, blue color like I want.

The size of the prime tower you want will depend on the filament you are purging. Red and white, for example, blend well together to make pink, and will require a larger prime tower than maybe red and green. All of the sizing settings should be in the Dual Extrusion section when you enable prime tower. Make the thickness greater or equal to half the prime tower's size to make a solid prime tower.

All done! With the main stuff that is. Every machine requires fine-tuning. I hope instructables this was helpful. Please feel free to leave comments and share!

If you're struggling, don't hesitate to ask for help. I'd recommend posting your problem with pictures and/or videos on the TEVO Tornado Facebook group. I normally hang out there and will probably see it.

Happy Printing!

If you wish to print with flexible filament such as PVA, you will need to print this in order to prevent the filament from bind up behind the extruder gear with the long retractions take place. Just add a bit of glue and snap it into place like on the photos.

This print is only compatible with the TEVO Titan Extruder.