Update 19-Mar-2017 New and improved revision of the printhead is available from here.
This set of things allows to upgrade Velleman VERTEX K8400 printer with single- or dual-head E3D hot-end.
Almost all other designs that "marry" K8400 with E3D are reducing print area because of 2 reasons:
- new hot-end is bigger than the original and
- the fans hanging on E3D heat-sinks take a lot of side or front space.
My design allows to attach E3D hot-end(s) to K8400 and gain extra print space. No need to re-position X and Y home sensors, however you may need to adjust the positions of the pulleys, as the new print head literally uses every single millimeter of available space.
New distance between nozzles is 23 mm; the original was 23.7 mm
X max = 210 mm (0..210); the original was 200 mm (0..200)
Y max = 193 mm (0..193); the original was 180 mm (20..200)
Z max = 190 mm - no change
IMPORTANT: This design fits the GENUINE E3D hot-end http://e3d-online.com/E3D-v6/Full-Kit/v6-1.75mm-Universal-Bowden It cannot be used with Chinese replicas that are bigger in size.
DISCLAIMER: This hot-end replacement requires soldering skills. If you don't have such skills, you may end up damaging your printer. If this happens - total responsibility is with you.
- One or two E3D v6 HotEnd Full Kit - 1.75mm Universal (with Bowden add-on) (12v). You can purchase them from here: http://e3d-online.com/E3D-v6/Full-Kit/v6-1.75mm-Universal-Bowden
- One 40mm x 40mm x 20mm 12V or 15V high speed fan (attached image shows the exact model I used)
- Four M4 x 16mm hex socket cup screws
- Two M3 x 12mm screws and two M3 x 6mm screws, or
four M3 x 12mm screws and two 5mm high plastic spacers.
- Four countersunk screws M3 x 50mm and four self-locking M3 nuts. They all are part of the original hot-end mount and can be re-used.
- Two M3 x 10mm screws.
- Heater cartridge(s) - one per print head. You MUST reuse the original ones from K8400. Do not install the cartridges that came with E3D as they are for 12V, while the printer supplies 15V DC.
- Optionally, six bright white LEDs with 5mm diameter and six 510 Ohm 0.25 W resistors.
Three designs in one
The set of thing files allows to build print head in 3 different configurations.
1) With LED lights and filament cooling ducts
2) With LED lights and no filament cooling
3) With filament cooling and no lights
Print the subset of the files matching your preferred option. See details in file descriptions below.
- main.stl - main body for configurations 1 and 3 (with filament cooling ducts). Print with Touchbed support.
- main_no_duct.stl - main body for configuration 2 (without filament cooling ducts). Print with Touchbed support.
- holder.stl - central piece holding E3D heat-sinks. Print with Touching Bed support.
- holder_with_support.stl - same as holder.stl, but includes easily removable support. Print without support.
- right_holder.stl - holding piece for right extruder
- left_holder.stl- holding piece for left extruder
- insert.stl - extruder board and PTFE Tubing holder. Slides in above the fan.
- cable_holder.stl - optional piece allowing to tie and hold the extruder cable
- duct.stl - air duct for configuration 3 - without LEDs
- duct_with_LEDs.stl - air duct for configuration 1 - with LEDs
- LED_holder.stl - LED holding piece for configuration 2 - without duct.
- dummy_e3d.stl - This piece replicates E3D shape and should be used in single print-head setup as a replacement of the left extruder. This is required to provide proper air flow.
- Power off the printer and unplug AC power cord.
- Disconnect all wires from the extruder board and unplug the cable from it.
- Disassemble print head(s), but leave all three XY CARRIAGES in place.
- Keep four M3 x 50mm COUNTERSUNK SCREWS and their nuts; we will reuse them.
- Carefully remove original heater cartridges from heat blocks. We will reuse them as well.
- Carefully replace the resistor on the extruder board with new resistor as shown on the image. The resistor should be chosen based on the voltage and current written on your fan. K8400 printer has 15V power supply. The label on my fan says 12V 0.24A, so I had to drop 3 volts on the resistor. Using Ohm's law calculating the resistance: 3 / 0.24 = 12.5 Ohms. Rounding to the closest standard value gives 15 Ohms. Power of the resistor is calculated as: 3 * 0.24 = 0.72 W. Rounding up to the standard value gives 1 W. So, I used 15 Ohm 1 W resistor, but you may need to do your own math if you use a different fan. Obviously, if you have 15V fan than you just need to replace the resistor with a piece of wire.
- Place the printer on the side to get access to the main board and the power supply.
- Unplug fan connector from the main board (it has black and white wires). Check if fan wires can reach the power supply's free -V and +V connection points. Extend the wires, if needed, and connect black wire to -V and white wire to +V.
- Put the printer back into vertical position.
- Use round file or dremel tool to give E3D heat-sink(s) the shape shown on the image. This cutout allows to place the hot-ends closer to the center of Y-axis rod. Do not over-cut; remove just enough amount for the rod to pass through the opening. The deepest point of the cutout should be within 5.0-5.5mm from the outer edge of the heat-sink. The height and the location of the cutout should exactly match the one on the image.
- Assemble E3D hot-end; follow the instructions published here: http://wiki.e3d-online.com/wiki/E3D-v6_Assembly Install the original heater cartridge from K8400 and the temperature sensor from E3D kit.
- Extend the length of all 4 wires coming from the hot-end up to 20cm. You can use black and red wires that are included into E3D kit. Solder the wires and cover junction points with heatshrink tubing also included into E3D kit. Make sure all 4 wires together can fit into the channel in the Main thing as shown on the images. Orientation of E3D cutout, heat block and heat cartridge should be exactly as shown on the images.
- Place the Main thing on top of XY CARRIAGES, place the Holder thing inside it and mount them together to XY CARRIAGES using four M3 x 50mm screws and four self-locking M3 nuts.
- Place the fan inside the opening above the Holder thing. Make sure the air flow direction arrow on the fan points down. The wires should exit towards the back of the printer. Pass the wires through the big opening at the back on the Main thing and push the fan all the way back and down. We will use only red and black wires. If your fan has blue wire, cut it off prior to installing the fan.
- Slide in the the Insert thing above the fan. It is designed to go in tight and hold the fan in the position without additional screws. If Insert thing doesn't fit, sand it to make it thinner.
- Attach extruder board to the Insert thing as shown on the images. If you decide to install optional, Cable_holder thing, use two M3 x 12mm screws to mount it at the back of the board and two M3 x 6mm screws to mount the front of the board. Without Cable_holder you can mount the board with four M3 x 6mm screws. Another option would be to use four M3 x 12mm screws and 5 mm height plastic spacers similar to those that are between the main board and the bottom of the printer. The spacers (if used) should be placed on top of the board.
- Install the first E3D hot-end between Holder and Right_holder. Make sure the cutout faces Y-axis and all the wires are running towards the back of the printer. Attach the Right_holder thing with two M4 x 16mm hex socket cup screws. Tighten the screws and make sure the outer side of Right_holder thing is precisely aligned with the side of the Main thing.
- Mark the wire ends to easily distinguish the pair coming from the heater cartridge from the pair coming from thermal sensor. Pass the wires under X-axis and push them up through the wire channel in the Main thing. Pull out the wires from the top up to the point when they are still slightly loose around X-axis but higher than the nozzle end. Fix the wires in this position with nylon wire tie attached from the top of the Main thing. The tie should not allow the wires to fell down into wire channel (see the images).
- If you have a second E3D hot-end - repeat the previous step and mount it with Left-holder thing. If you have only one hot-end - attach Dummy_e3d thing to the Holder.
- Shorten the wires and connect them to the extruder board as shown on the image.
- If you have 2 hot-ends you need to adjust them vertically. The Holder things, when screws are not tightened, allow to slightly move the hot-end up and down. This makes the adjustment very easy. First level the print bed using only one hot-end as described in printer's manual. Then adjust the position of the second to match the first.
- If you are installing LEDs - solder them to resistors outside Duct_with_LEDs, or LED_holder thing. Then insert the LEDs into the holes. Positive end of the LED should be connected to the resistor. All the negative ends of LEDs should be connected together and all free ends of the resistors should be connected together. Solder black wire to the negative ends of LEDs and a red wire to the resistors. There are 4 holes connecting middle part of the thing with its sides. It is easier to pass the wires through these holes in the direction from the center to the side of the piece. The order of soldering the wires does not matter, but I found more convenient to start from the center and then cut the excessive wires on the sides. Solder 20 cm long wires to the center section. Pass the wires through the hole at the front of the Holder thing. The wires will come out from the back and you will need to connect them to the extruder board (see the image).
- Move the print head manually to each of 4 corner positions and make sure it does not touch pulleys and the belts.
Marlin, Repetier Host and CuraEngine settings
Modify the following values in Configuration.h file:
X_MAX_POS 210 (old value 200)
Y_MAX_POS 193 (old value 200)
Y_MIN_POS 0 (old value 10)
MANUAL_X_HOME_POS 210 (old value 200)
MANUAL_Y_HOME_POS 193 (old value 200)
Under Printer Settings -> Printer -> Park Position
X: 210 Y:193 Z min: 0
If you have 2 extruders
Under Printer Settings -> Printer -> Extruder -> Extruder 2
Offset X: -23 Offset Y: 1
Note: Above offset values need to be fine tuned. For calibration I used cube4 from http://www.thingiverse.com/thing:12069
Under Printer Settings -> Printer -> Printer Shape
X Min: 0 X Max: 210 Bed Left: -28.7
Y Min: 0 Y Max: 193 Bed Front: 0
Print Area Width: 240 mm
Print Area Depth: 215 mm
Print Area Height: 190 mm
Under Print -> Extrusion
Enable Retraction - checked
Retraction speed: 70 mm/s
Retraction distance: 4 mm
Minimum distance before Retract: 0.2 mm
Minimum extrusion before Retract: 0.02 mm
Travel: Slow: 100. Fast: 100
Above values are the only ones I changed. They work for me with 0.35mm nozzles, which I purchased separately. If you will use 0.4mm nozzles that are part of E3D set, you will need to change also few other Cura settings, like for example Infill under Print -> Structures. Goggle to find out how Cura settings depend on nozzle diameter.
My starting point was the design suggested by Big-Bert here: http://forum.velleman.eu/viewtopic.php?f=64&t=13655&start=105
It allows to keep nozzles close to each other. Then I added single 40mm x 40mm x 20mm 12V 0.24A fan that is powerful enough to cool down both heat-sinks and the filament.
One of the goals was to re-use the original M3 x 50mm screws as longer screws are hard to find. I found the way to do it.
Tight space doesn't allow to have wires hanging around the print-heads, so I had to make the channels in the main thing to pass them through.
My old print-head had add-on lights http://www.thingiverse.com/thing:825628 which I liked and I decided to add 6 LED lights to the thing. Due to aforementioned reason LED wires are also hidden inside.
As you can see from the images this print-head uses every single available millimeter of the space. My Glass Holders http://www.thingiverse.com/thing:1504426 are required to utilize entire 210mm x 193mm area and avoid collisions of the nozzles with the original glass holding clips. Additionally, you will need to adjust Marlin, Repetier and Cura settings as described in Post-Printing section to gain that extra volume.