Stage 04: Hotend

Written By: Makertech

Comments: 12
Favorites: 0
Completions: 21

Difficulty

Moderate

Steps

Time Required

00:25:00 - 00:30:00

Step 1 Hotend Pack Parts

Check that you have all of the components photographed from the Hotend bag.

Check that you have all of the components photographed from the Hotend bag.
Allen Key
Thermistor and heater cartridge
PTFE Tubing
The tubing can be put to one side for now, also the included golden coupling is not used, you can remove it and keep it as a spare.
Hotend assembly with fan

Edit

Step 2 Heater Cartridge and Themristor Cable Lengths

A mistake was made by our supplier for a batch of the heater cartridge and thermistor (red and white cables) cable lengths. Their lengths should have been 1.2m, however some are only 1m long.
If you have cables that are 20cm too short you can (in order of quickest):
Solder, use cable blocks or crimp to add extra cable. For the heater cartridge you need to use 24AWG. For the thermistor you can use 28AWG.
Order a longer set locally. The heater cartridge is 24V, 40W, 6*20mm. The thermistor is a 100k NTC thermistor. They are both very common and cheap parts (little over a dollar each), you should be able to find them on sites like Amazon, eBay and Aliexpress:
Heater Cartridge: 24V 40W 2M
100K Thermistor: XH2.54 2M 1pc
Or get in touch with us by completing this form.
If you are waiting for a replacement you can still wire the shorter cables, you can get slightly more length by not including it in the main stem and routing it along the support beam instead, then plugging it in with the gantry lowered. For the mean time though this does result in a lower max z-height.

Edit

We have received the short cables. Can we limit the max z axis height in the software? Or do we need to keep this in mind when printing individual parts?

Daniël KN - Aug 2, 2020 Reply

In Cura you can set a new Z-height that will warn you if a part your printing is too big, until you receive the correct length cable.

Makertech - Aug 3, 2020

The thermistor has the wrong connector as well. It should be a JST (as shown in the wiring stage) rather than the female jumper connector (as shown above). Albeit, since I have a stash of JSTs and had to splice the extra 20 cm anyways … well, it wasn’t all that big a deal.

Andrew LeRoy - Aug 11, 2020 Reply

A decent network patch lead is 24AWG (most are clearly marked on the outer insulation but do check as cheaper ones can be made out of thinner stuff). They make a great source for the extra cable needed if anyone is trying to find some suitable cable in a hurry.

Mike Cheadle - Aug 14, 2020 Reply

I used that hack a long time ago on my prusa and it still works

Ali Kara - Feb 21, 2022

These cables (2 meter is the next size) do not appear to be available in the USA which means shipping for purchased replacements will be two weeks or more. At this time my assembly has come to a sudden halt. I have already asked for the correct part to be sent but am getting no respone. Is there another viable alternative ?

Richard Szanti - Aug 18, 2020 Reply

Ug. 2-months unless I want to pay $60+ to get it in 2-weeks from AliExpress to the US, doesn’t seem very readily available at the moment. I’ve requested the replacements, though I guess I’ll try and solder and extend these and see what happens… Ug.

Jay - Aug 23, 2020 Reply

Step 3 Detatching the Fan

The fan mount assembly pops off the heat sink like shown.

The fan mount assembly pops off the heat sink like shown.
Check that you have a 24V fan.

Edit

Step 4 Disassembling the Hotend

Disassemble the Hotend like shown.
Heatsink assembly
PTFE Coupling
Heatsink
Throat
Heater-block
Nozzle

Edit

Step 5 PTFE Tape

Wrap several layers of the included PTFE thread tape around the threads of the throat and nozzle as shown in the image.

The tape should be wrapped around the shorter part of the thread on the throat.

Use a craft knife to scrape away the excess PTFE tape.

Wrap several layers of the included PTFE thread tape around the threads of the throat and nozzle as shown in the image.
The tape should be wrapped around the shorter part of the thread on the throat.
Use a craft knife to scrape away the excess PTFE tape.
Make sure that the openings are clear of the tape.

Edit

Step 6 Reassembling the Hotend

Reassemble the Hotend making sure that there is a gap between the heater-block and heatsink.

Reassemble the Hotend making sure that there is a gap between the heater-block and heatsink.
Begin by fastening on the Nozzle
Next screw on the heatsink assembly.
With the PTFE tape around the threads you may need to use a set of pliers to screw the nozzle and throat into the heater-block.

Edit

Step 7 Heater Cartridge

Unscrew the bolt on the side of the heater-block by a few millimetres.

Take the heater cartridge and thermistor cable assembly and push the heater cartridge into the large hole...

...and the thermistor into the smaller hole.

Unscrew the bolt on the side of the heater-block by a few millimetres.
Take the heater cartridge and thermistor cable assembly and push the heater cartridge into the large hole...
...and the thermistor into the smaller hole.
Position the Heater cartridge to the centre of the heater-block and fasten town firmly the bolt that clamps it in place.
Take care with thermistor bead, it is fragile!

Edit

Step 8 Thermistor

Carefully wrap the thermistor cables around the bolt head.

Do not fasten it down tightly, it just needs to hold the cables, fastening it down tightly will cause the wires casing to split and it's core to short on the block.

Carefully wrap the thermistor cables around the bolt head.
Carefully fasten the bolt down.
Do not fasten it down tightly, it just needs to hold the cables, fastening it down tightly will cause the wires casing to split and it's core to short on the block.