Introduction: Prusa I3 Modular Print Head

Hey guys, Chris Ray here and today we'll be looking at my newest creation; A modular print head for the Geeetech Prusa i3 pro B. I call it the CPH Mark III. This Design is by far the best that I've seen on a prusa that has a direct drive. The goal of this project was to have a super light, sturdy, and compact design. This was in order to get the fastest printer possible that still retains a direct drive for flexible plastics. Not only did I hit my goal for all of these points, but I also was able to make this modular. This means that in order to remove the entire print head all you must do is remove 2 screws located conveiniently on the back, as well as remove a single cable connector from the top of the printer (demonstrated in the video). So guys, without further adieu, lets get into the build!

Step 1: Getting the Parts

Okay guys so first thing's first. Deciding on all of the parts took me a couple of weeks worth of research. Luckily for you, this means that it will take you no time! Here's what I got:

E3d Titan Extruder:

-Geared extruder (so we can use a smaller motor)

-Tight tolerances for flexible filament

-Plastic construction (only weighs 60g)



E3d V6 Hotend:

(I used a Chinese one because it was full metal instead of a PTFE tube)

-One of the most popular hotends on the market

-High max temp for high temp plastics

-full ss construction (sorta)

Chinese one:

E3d one:


NEMA 17 Pancake Stepper Motor:

-Small & Light



Hatchbox PET-G Filament:

(you can get the STL files and print instructions on thingiverse: )

-Durable for making the frame




-Self locking

-Easy Removal

Digikey: x12

Step 2: Get the Motor Ready

okay, first you'll need to take the gear from the E3D Titan and put it on the motor like you were about to assemble the Titan. Fit the Titan on and make sure you have the gear right where is should be. When you place the Titan frame on the motor the gear on the motor should stick past the black gear about one mm instead of being flush. (this will make sense in later steps)

Step 3: Assemble the Business End

Great. Now that the gear is in the proper spot on the motor we can assemble the titan and V6 WITHOUT THE MOTOR. This may seem odd to you (which it is) but what you want to do is assemble everything in the Titan without the motor poking through. When you get to the tensioner arm just let it rest between the spring and drive gear like usual (the tension will have to be completely backed off for this to work). Don't worry about putting any screws in yet, the one that would usually go behind the V6 isn't going to be used.

Step 4: Ready to Go

Now that you have the extruder together, it's time to put the smallest screw in the hole beside the titan. (First 2 pictures) This will make sure all of your hard work doesn't pop apart when you move it because now it's time to slide the extruder into the frame. (3rd Pic) Now all that you have to do is get the motor through that big hole and through the tensioner.

Step 5: Bolt It Together

Now all that is left is to screw it all together. The top 2 screws are M3 x 35 and the bottom one is M3 x 30. (They should have all came with the Titan) Flip it back over so the motor is face up and do a little wire management like in the second picture.

Step 6: Wireing

Last you need to wire up your connectors. I'll let you guys figure out exactly how you want to do that. What I ended up doing was just cutting the wires off of my old print head because they already were connected to the board with the proper connectors. Then it was just a matter of soldering and heat shrinking all of the wires onto the connectors and making sure I had all of my pins lined up correctly.

!!!REMINDER!!! Remember to write down your pin layout for making more printheads in the future that will need to plug into this. (3rd Picture is an example)

Step 7: Wrap Up

I hope this was enough information to help you guys build your own! If you have any questions don't hesitate to ask. Also, if you want to see more of my project you can find me here:





About This Instructable




Bio: I love programming, 3d printing, and electrical design. I am about to start my 1st year at PennState.
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