1.75 direct drive extruder,

OK,recently i've had enough of the accessible wades extruder and the whole hobbed bolt and printed gear thing, unless you have a bolt that is hobbed properly, it's a nightmare to get properly setup,  the other main problem is that the wades extruders were really built for 3mm filament, which is fine , but it's hopeless for 1.75mm due the filament packing up under the hobbed bolt

i took some inspiration from several existing designs, the mk7 and an modification done to the up! by DrewPetitclerc (pictured above) and devised my own extruder that mounts on the standard 50mm hole spaced x axis carriage

so far it is only 1 printed part and 1 machined part and a spring from an artline pen 

so far this has actually proven quite reliable,  since the moving parts are kept to a minimum and the rate of flow is at the mercy of a hobbed filament driver, not two printed gears and a hobbed bolt, the kind of quality prints i get off this now are better than what comes off the up! and with slic3r now doing support material which literally falls off the only other problem to solve is my abs parts lifting of the table which i think might be more the crappy abs which i don't think is actually abs this extruder is now available as a printed part complete with spring and filament driver gear on our website www.3dindustriesaustralia.com.au

stl files for it are now on thingiverse,@ http://www.thingiverse.com/thing:34896

AluhotendV2

After many many hours of testing my 1.75mm ALUHOTEND and getting a lot of interest from, the one common question i have had people ask "is there a 3mm version?" aside from questions about the strength of the constriction..

so i've done a 3mm version based on the 1.75mm version the wall thickness on the constriction remained the same but the length is double compared to the 1.75mm one, fins on the cold side are now thinner and there are more of them, the threading works out better because it goes deeper into the cold side, 

this one is jthe length will hopefully be shorter i have done testing on it with some old 3mm abs i had lying around as so far so good this will be Aluhotendv2

to be released mid january 2013

UPDATE*  the 3MM version of this hotend has been delayed due to some issue with the lathe and parts that needed replacing, that and a high demand for filament drives, we are now looking at late january to very early FEB  there has also been some design changes it is now shorter than an mk2 jhead and the constriction is slightly longer but hides internally, the highest recorded temperature on the cold side with no active cooling has been 45c with the nozzle at 240c

Wades Accessible Extruders - Openscad - Jhead

The Accessible Wades Extruder: Looking at just about all the models on thingiverse for the accessible wades extruder there is always somthing to drill out or cut off which looks ugly afterwards eg. the block under the hinged version , the webbing in the holes ?  the scad files responsible for producing these were written back when slic3r was in nappies and when support material sucked, however today we've got prusas putting out quality prints that leave serious questions of the commercial machines and slic3r doing some amazing support material that pretty much falls off

looking at the scad code for the Accessible Wades Extruder from

http://www.thingiverse.com/thing:6713

bearing in mind that this file is Dependant on several others in the prusa collection of scad files there are a few main problems one of them is that groovemount doesn't give you a model with a groovemount it just gives you the old fashioned mounting which required glue,  here's the original code:

module groovemount_holes ()

{

extruder_recess_d=16;

extruder_recess_h=11;

// Recess in base

translate([0,0,-1])

cylinder(r=extruder_recess_d/2,h=extruder_recess_h+1);

}

as you can see there is no code for the retaining holes, so i borrowed code from version 3 (the hinged one) and replaced it:

module groovemount_holes ()

{

extruder_recess_d=16.5;

extruder_recess_h=10;

// Recess in base

translate([0,0,-1])

cylinder(r=extruder_recess_d/2,h=extruder_recess_h+1);

for (hole=[-1,1])

rotate(90,[1,0,0])

translate([hole*(extruder_recess_d/2-1.5),3+1.5,-wade_block_depth/2-1])

cylinder(r=1.5,h=wade_block_depth+2,$fn=10);

 }

this solves the hotend mounting issue , the next part to sort out is the webbing in the holes the first part is in this module:

module motor_mount_holes()

{

radius=4/2;

slot_left=1;

slot_right=2;

{

translate([0,0,screw_head_recess_depth+0.5])

for (hole=[0:2])

{

translate([motor_hole(hole)[0]-slot_left,motor_hole(hole)[1],0])

cylinder(h=motor_mount_thickness-screw_head_recess_depth,r=radius,$fn=16);

translate([motor_hole(hole)[0]+slot_right,motor_hole(hole)[1],0])

cylinder(h=motor_mount_thickness-screw_head_recess_depth,r=radius,$fn=16);

translate([motor_hole(hole)[0]-slot_left,motor_hole(hole)[1]-radius,0])

cube([slot_left+slot_right,radius*2,motor_mount_thickness-screw_head_recess_depth]);

}

translate([0,0,-1])

for (hole=[0:2])

{

translate([motor_hole(hole)[0]-slot_left,motor_hole(hole)[1],0])

cylinder(h=screw_head_recess_depth+1,

r=screw_head_recess_diameter/2,$fn=16);

translate([motor_hole(hole)[0]+slot_right,motor_hole(hole)[1],0])

cylinder(h=screw_head_recess_depth+1,

r=screw_head_recess_diameter/2,$fn=16);

translate([motor_hole(hole)[0]-slot_left,

motor_hole(hole)[1]-screw_head_recess_diameter/2,0])

cube([slot_left+slot_right,

screw_head_recess_diameter,

screw_head_recess_depth+1]);

}

}

}

the line we need to change:

 

translate([0,0,screw_head_recess_depth+0.5])

if you take out the +0.5 the webbing will dissapear and the holes go right through

lastly there is the webbing that the hobbed bolt hast to go through

the section of code that had to be changed:

translate([0,0,9])

cylinder(r=m8_clearance_hole/2,h=wade_block_depth-9+2); 

this is referring to the space above the webbing a 608 bearing is 7mm wide not 9mm so when it is moved 2mm down the webbing also dissapears:

translate([0,0,7])

cylinder(r=m8_clearance_hole/2,h=wade_block_depth-9+2); 

additionally if you want to use 1.75mm filament with this extruder find this line:

filament_feed_hole_d=4;

in the top section of the file and redue the number to 2mm after it's printed put a 2mm drill bit through it and you've got wades extruder that will do 1.75mm filament without packing up under the hobbed bolt

i've pre generated both types with jhead mounts

http://www.thingiverse.com/thing:34890