Many high-end 3D printers require large service fees, and in most cases require a technician to perform repairs or upgrades. When designing the EVO,  Airwolf 3D didn’t want to go down that road as customers could be stuck for days, if not months without their machine. The EVO was designed to be a modular system, and replacing the head can be done fairly quickly.

The modular hot end system on the EVO Additive Manufacturing System.

There are a few reasons you may need to change the hot end on your EVO, with the most common reason being that it has reached the end of its life cycle and needs to be refurbished or replaced. The hot end on the EVO is made to withstand high temperatures for long periods of time and can last up to 2,000 hours if treated well, but this also depends on the materials you are using.

The front view of the hot end on the EVO.

It is suggested to keep an extra hot end lying around, as this can also serve as a swappable head for your machine if you would like to have it set up for different materials, or have two different sized nozzles. For example, if you would like to have a hot end setup for larger parts with 1mm nozzles installed, and one for fine parts with .35mm or .5mm nozzles. Having a backup also serves as insurance if your current hot end needs to be repaired. This way you can send in the malfunctioning or worn-out hot end to be fixed while you use the backup.

Swapping out the hot end on the EVO has been made extremely easy. Follow the steps below or watch the video guide.

Changing Out the Hot End:

Turn on the machine and preheat the nozzle to the temperature that applies to the loaded material. PREHEAT -> ABS (for example) -> N1

Preheating the nozzle and removing the filament on the EVO.

Once preheated, remove the filament. FILAMENT CONTROL -> REMOVE.

Turn off the machine and let the hot end cool down to room temperature.

Go to the back of the machine so that you can see the plugs in the back of the hot end.

A look from behind the hot end showing the wiring harness plug.

Using your hands, try removing the plugs by squeezing the sides and pulling. Be careful not to pull on any of the other wires. If they do not remove by hand, use a pair of large needle-nose pliers to remove the plugs for both heads.

Removing the wiring harness plug with large pliers.

Turn back to the front of the machine and locate the two holes on the outer side of the fan shroud screw holes on the front of the hot end. Insert an M3 hex wrench and loosen both bolts. With one hand holding the bottom of the hot end, finish removing the screws and pull the hot end from the machine. It should easily drop into your hand once the screws are removed.

The two circles shown above are the access hole locations for the M3 wrench.

Use an M3 hex wrench to insert into the holes and remove the bolts.

Make sure to keep your hand under the hot end while loosening the bolts.

If the new hot end needs bolts, remove the fan shroud from the old hot end and remove the hot end bracket bolts. Place these in the new hot end.

New bolts being inserted into a new hot end.

Screw the new hot end into the hot end bracket with the two installed bolts. Make sure they are lined up correctly and that the hot end sits flat against the bracket. You may need to look at the hot end from the side to make sure.

A side view of the hot end being lined up to the hot end bracket.

Installing a new hot end onto the EVO.

Turn to the back of the machine again and locate the two hot end plugs. It is suggested to put dielectric grease on the connectors. Plugin the plugs to the correct head and double-check to make sure they are in all the way.

Level the nozzles and run a test print.

Make sure to level the nozzles before printing.

You can also view this lesson at