Designed to be used with the Volcano Fan duct I created for the TEvo LM
Created this to fix several issues on the Tevo Little Monster floating extruder design as well as make up for some engineering fails from E3D. This part is designed to be used with the above volcano fan duct I made for the legitimate E3D volcano hot end.
The item is designed to take the strain from PTFE tubing and floating effector off the effectors Bowden fitting on the Tevo Little Monster to prevent clogging in the E3D volcano hotend. The PTFE tubing is chewed up by the crappy fitting that comes in E3D hotends (and can't be replaced with a decent metal screw in one) when the delta effector moves around under the floating extruder. The movement not only chews up the PTFE tubing, it also allows the tubing to move up and down inside the hotend no matter what clip goes on the Bowden fitting. This causes a jam due to hot filament getting in between the gap created between the end of the PTFE tubing and the heatbreak during retractions (inside the hotend) preventing the filament from feeding or retracting. The strain relief prevents this by moving and isolating the motion of the tube up and away from the bowden fitting and also holding the tube down firm against the bottom of the heatbreak inside the hotend. This works so well you no longer need the clip on the fitting if you choose not to.
I also added in a channel and clamp for my wiring to feed in behind the support for the PTFE tubing making use of the redundant BLtouch holes already in the effector (if you haven't already thrown that crappy BLtouch out, it is time to do so). This clamp is designed to be easily removed in the case you need to replace the strain relief or remove the electronics from the effector at some stage etc. My soldering skills are pro so I only needed a small amount of extra room around the shielded cable to do my wire connections in the back of the fitting, you can of course make the solder connections down lower away from the strain relief if you need more room.
I have added several sizes for the various PTFE tubing as there is a lot of variation in the outside dimensions of the various PTFE tubing being sold, just make sure you print the matching clamp for the size you choose. The Capricorn tubing from filastruder is recommended for the connection between the extruder and hotend (4.2mm size strain relief) due to the strict inner diameter of this tubing ensuring the best possible constrain of your filament and trouble free flexible filament printing.
UPDATE: I have found there is a variance in the BLTouch effector mounting holes between the older and newer Tevo Little Monsters (holes are closer to centre of effector on older models), there is no need to actually put bolts through these additional mount points so I haven’t updated the file. I have not bothered to use the bolts despite having designed them to be used.
Hobbyking Black ABS
245 C hotend
110 C Bed
50* Heated Chamber
No Fan cooling on part
You will need to Select the size body you need based on the PTFE tubing you wish to use and it's matching Clamp, the cable clamp and press are universal size for all 3. (Capricorn is the 4.2mm one and is the smallest outer diameter PTFE tubing I have come across for 1.75mm filament)
Additional support added on top of 2mm auto generated support to ensure the tall support area in the middle of the print does not fail during the print (just ass some more 3mm support manually to bulk it out).
Although there is probably no need to print this part in ABS, I still recommend you do this due to the potential for the part to warp if you decide to fully enclose your Tevo Little Monster (which you should do).
There is no need to use the rear screws to hold down the very back of the strain relief, I put the holes and chamfer there so you can use a couple of button head bolts if you want, just put these in first before adding the main 4 bolts.
3 x M2.5x8mm bolts (cable clamp)
4 x M3x15-30mm bolts (effector attachment)
2 x M3x10mm bolts (PTFE clamp)
Make sure you look for the side of the cable press that should be facing up, it has a more rounder surface to it. When you put the M2.5 bolts in take it easy, it is only threading into plastic with really small threads, it needs little pressure to snug the bolts up enough to hold the clamp in place.
When adding the PTFE tube clamp made sure you have some filament in the tubing, it only needs to be tight enough to stop the tubing from being pulled out so don't go crazy as you don't want to clamp down on the filament inside of the tubing. When you do this make sure you have a clip on the Bowden fitting on the hotend and push the tubing all the way down and keep some pressure on it while you snug up the clamps bolts. Then flex the tubing over about 45 degrees and make sure the filament slides through without too much back pressure to simulate the worst possible angle between effector and floating extruder. Just back one of the 2 bolts back a "poofteenth" if it starts to bind.
I took the effector from Cinpro and imported it into fusion360. From there I fixed the dimensional errors and then built this part up of the corrected effector dimensions (as per the pictures).