Printing soft TPE filament was a challenge on my Wanhao Duplicator i3. The elastic filament would escape the filament channel and stop extruding. This replacement body has a tight fitting channel that actually mates with the idler wheel, leaving no room for the elastic filament to escape.
Print in the orientation provided for best results and redrill the filament channel to 2mm. You have the openscad file and it's a culsomizer if you need to tweak the part a bit for your particular 3 series extruder.
Note: TPE filament has a tendency to grab onto dirt. Keep it clean. Also, I think it kind of breaks down when at high temperature. I clean the nozzle before long prints with PLA atomic pulls. Also, I turned off retraction because the advice on the forum. Thanks!
Music wire poke out. I stick a thin piece if thin steel wire through the nozzle and it helps.
Atomic Pull: Heat the nozzle. Manually push through PLA filament so it squirts out most of the garbage. Let cool to 85C or by experience. Slowly and smoothly pull the PLA from the nozzle. It should stretch and pull a plug of plastic out of the extruder nozzle. The tip should look pointy like a little mold of the tip of the nozzle and dirty plastic may be visible. Do it enough times until you think the nozzle is clean. It helps to use a different color
Print this in the orientation provided for best results. Redrill the filament channel to 2mm. let the drill follow it's natural course down the channel.
Don't Panic! To Continue a stopped print!!!!
The rope pushing extruder seems to just buy time. The nozzle will plug up on occasion maybe during a long print.
If you're using a program that has ASCII g-code, you can edit the g-code directly. In my case I'm using an old version of Cura (32bit).
Don't remove the stopped print from the bed.
First you need a digital caliper ( https://en.wikipedia.org/wiki/Calipers#Digital_caliper )
This is a great tool by the way. Always useful.
Use the digital calipers to measure the height of the existing print
-Open the Digital caliper wider than your existing print is tall.
-With the butt end if the digital caliper, make a depth measurement. Try to find a place on the print where the inner bar can touch the bed while close enough to the top layer for the butt of the caliper when pressed down. ( see. Depth Measurements: https://www.thegeekpub.com/4089/how-to-use-digital-calipers-the-right-way/ )
This is the height of your print. To find out the number of completed layers divide this measurement by your layer thickness. In my case the height was 6.2mm and the layer thickness was 0.2mm.
So it's about 31 layers. Now it's hacking time. Make a copy of your G-code file and open it with a good text editor. Not windows notepad. Recent versions of windows notepad are damaged and will insert extraneous line breaks! Use the indispensable Notepad++ on windows ( https://notepad-plus-plus.org/download/ ).
Below is the startup code for my cura g-code for a messed up print I was running.
I indicate my edits with **.
You must allow the printer to home X and Y to align the print head. (see "G28 X0 Y0 ;move X/Y to min endstops" below).
But!!!!! YOU MUST STOP THE Z-AXIS FROM HOMING!!!!
Stop the Z-axis from homing by commenting out the "G28 Z0" command by inserting a semicolon before the "G28 Z0" command on the same line. It is now ";G28 Z0" below.
Also, stop the startup code from driving around in the Z-axis. I commented the line ";G1 Z15.0 F4200 ;move the platform down 15mm" by adding a semicolon to the beginning of the line. This stops this.
It's fun to play around with the display message (see "M117 Luckey Magic...
You must trim away all of the completed layers of the print. Search for the your calculated completed layer from above. In my case the search string was "LAYER:31" to find the calculated completed layer which was 31. Your slicer might comment the layers differently. Look at the comments of the first layer in your g-code file to figure this out. In the beginning of the searched layer, there will be a g-code command that sets the height of the platform. In my case it was "G1 Z6.700". You want this to be the next layer above your digital caliper measured height. Since the 6.7 I observed was too high I searched again for the previous layer "LAYER:30". Layer 30 had "G1 Z6.500" which indicates 6.5 in the Z-axis which seemed close enough for me.
Click above the layer comment, hold the shift key and press and hold the page up key highlighting the code above the Layer comments until you reach the startup code. Press the delete key and wipe the highlighted code.
SET THE Z-AXIS HEIGHT VALUE!!!!!
You need to set the value of Z-axis value of the printer without moving so the print will not crash when you continue. We will move the print head manually to touch off on the top of the existing print. I added "G92 Z6.3" below to set the Z-axis height to our continuing layer our 0.2mm layer thickness.
Save this edited g-code file to your SD card and plug it into the 3d printer.
First unclog the extruder with atomic pulls or poking a wire in the hot nozzle or what ever method you like and reload your filament and get the extruder working correctly again.
**Manually touch off the top of the existing print.
Bring the print head near the top of the existing print with the printer controls, then disable the motors.
By hand slide the print head over the left most edge of the existing print and turn the left ball screw by hand until the print nozzle just touches the existing print. By hand slide the print nozzle over the right most edge of the existing print and by hand turn the right ball screw until it just touches the existing print. Repeat this processes until no ball screw adjustments are needed.
Preheat the nozzle.
Start your Edited G-code file. If it fails stop and figure out why else congratulations.
PS. Once it's going you can adjust your platform knobs for the first layer.
;Sliced at: Tue 02-10-2018 15:36:18
;Basic settings: Layer height: 0.2 Walls: 2.8 Fill: 100
;Print time: 56 hours 31 minutes
;Filament used: 112.79m 336.0g
;Filament cost: None
;M190 S50 ;Uncomment to add your own bed temperature line
;M109 S230 ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
;We donot want Z to home NOOOOO!
;G28 Z0 ;move Z to min endstops
;The printer was going to move the platform down 15mm in the Z axis. We commented it out to stop this.
;G1 Z15.0 F4200 ;move the platform down 15mm
G92 E0 ;zero the extruded length
G1 F140 E30 ;extrude 3mm of feed stock
G1 X20 Y0 F140 E30
G92 E0 ;zero the extruded length again
;Inform the printer that it is at the desired height in this case 6.3 mm
;Put printing message on LCD screen
;play with the display
M117 Luckey Magic...
;Layer count: 170
G1 F2400 E8346.11690
G0 F4200 X54.914 Y39.299 Z6.200