This is a CR 10s Pro it's a 550 to 600 dollar printer this is an Ender
three you can buy one of these for under $200 this has a dual gear drive to push
the filament this has a single gear drive with an idler but did you know you
can buy that dual gear drive and put it on Ender three well we're gonna try that
I'll show you how to install it how to calibrate it and is it even worth it on
today's Filament Friday Filament Friday is brought to you by these patreon
supporters here's a standard extruder on Ender three it's got a gear and an idler
wheel and the whole frame is made out of plastic here's the dual drive a drive on
both sides and an all metal frame and actually a stronger spring this is the
one I'm going to use I bought this off of amazon.com I'll put a link to it in
the description below along with links to other locations where you can get the
same extruder here's the close-up of how it works it grips on both sides of the
filament and they're geared so they turn together so the first thing I want to do
is set a baseline so I need to measure 100 millimeters of filament so between
these two marks is 100 millimeters next I'm actually going to take off the PTFE
tube because I want to try this with no resistance no hot end no PTFE tube
nothing so I'm just going to push filament through you can see the little
marks and I'm gonna line that up so first mark is right at the beginning and
then 100 millimeters later is the second mark in order for the machine to move
any filament it has to be preheated even if we're not connected to the hot end so
I heated it up to 185 degrees C and then I go into the prepare move axis menu
down to extruder select 10 millimeters crank it up to a hundred and then let
this thing run and now it's been pushing the filament through you can see the dot
on the left and the hundred millimeter on the right and it stops right at the
hundred millimeter mark and that's because I've got my machine tuned if you
go into control motion and steps per millimeter you'll see the e steps this
is how many steps the stepper motor has to go to move 100
millimeters some of the early machines didn't have this but all the latest
ender threes and if you've upgraded to the silent board you have this on your
menu now I'm going to screw the PTFE tube back into the extruder and then
we're going to push some filament through and through the hot end I'll
measure out another hundred millimeters between the two marks and I'm actually
gonna push this filament until that first mark is lined up so you can see
the filaments losing out as I do it now I'll go to the prepare move access
extruder ten millimeters crank up one hundred millimeters again and then we're
gonna let this thing around and see how close we get so here it is moving and if
I let this run out it'll stop at some point now we're at 185 degrees C here
and you can see it stops way short like 24 millimeters short of where I would
expect it to be so let's crank this up to a higher temperature I'm gonna go to
205 which is typically what I print it with this filament see how close we get
so let's try it again at 205 now 100 millimeters push it into starting point
let it run and it stops pretty close but not perfect right there so we're looking
at about six millimeters so clearly there's some slippage going on as soon
as we had the PTFE tube and hot in it's slipping on the gear but at 185 degrees
C it's like 24 millimeters of slippage and 205 it's only six millimeters of
slippage so let's try the other extruder so let me show you how to remove this
the first step is to take the filament out and I'm gonna take the screw off of
the bracket or the arm and in the spring and then I'm gonna disconnect the PTFE
tubing and pull the wiring harness off the clip and then there's a screw at the
front here take that off and then there's one at the back corner take that
off you have to disconnect the motor from the wiring harness it just pulls
out and there's one last screw that holds the motor and now you can remove
the motor and the last piece of the extruder here's the kit that I bought
I'll put a link to this in the description below it is a kit so you
have to assemble it so let me show you how this works
eventually we'll get to this where the two pieces drive the filament on both
sides and the motor turns the idler gear the first thing I did was put the screw
into the bracket this will actually be the adjustment screw for the tension on
the spring and then there's a screw that goes into the arm and this will actually
hold the spring in place there's an insert that goes into the arm that goes
in here and it is a tall screw that goes into that insert and then this arm will
mount to the bracket like this and screw into the motor and then the spring will
go between the arm and the bracket now we got to remove the gear from the motor
there's two set screws to take it off the new one has one set screw so you
want to make sure that set screw goes on the flat side of the motor shaft now
we're ready to assemble so you bring the base of the new extruder to the machine
and tighten the first screw to the motor then tighten the second one on the right
front don't tighten that one all the way and in the background don't quite
tighten that one all the way it gives you a little wiggle room next we want to
adjust the gear so it lines up with the filament then we can bring in the arm
put that in position and tighten it in place now go back and tighten those
other two screws and back out the tension screw this insert goes into the
spring and then the spring pops over the screw on the arm and pops into the
tension location then tighten the tension screw until you start to see the
spring turn readjust the arm screw so it's tight but
still loose enough to move back and forth and we're ready to test I marked
two spots hundred millimeters apart I set to extrude it to extrude 100
millimeters so it starts extruding and let's see how close it gets not too
close it's way off thirty millimeters so we need to adjust the Estep so we take
the hundred millimeters we expect - the 30 millimeters we measure divide that
into the hundred millimeters and n times the east steps and we get one thirty
five point five seven so we need to change re steps to 135 point five seven
so how do you do that you go into the control menu and then you go into motion
and then you go into steps per millimeter at the bottom and then you go
all the way to the bottom of that you had the e steps per millimeter one
thirty five point five six say I've already changed it
you want to go to the control menu store settings click on it and that'll save
that setting come back to another hundred millimeters I started the
extruder to extrude 100 millimeters and here's where we're at now after the
change to the east steps you can see our almost perfect so we're gonna go with it
now we need to change the coupling on this guy to the big coupling it came
with it and put the PTFE tube in place so now we can test it with actual
filament there's even a locking clip for it so I
marked 100 millimeters of filament I set it 285 degrees C it's extruding and this
is where it stopped so if I measure this or six millimeters short of perfect much
better than the other extruder 185 let's see what it does at 205 so a 205 degrees
C the filament has gone through we're just waiting for it to stop this is the
second mark and then we can measure and there it stopped and if I measure six
millimeters same thing we got at 185 degrees C so now let's do a comparison
185 degrees C you can see the stock extruder slips a lot more than this
double gear drive but what about at 205 at twelve five percent really the same
they're both stopping six millimeters short that seemed to be a standard
slippage six millimeters short of what I expected but what I liked is it's the
same on the metal one whether it's 205 or 185 so now we can
recalculate if I use the six millimeters I can get a new estep of 144 point two
and with those new e steps that should compensate for the slippage so here's a
test that's the second mark and sure enough it stops right where I want it so
essentially zero error as far as print quality I'm not seeing a major
difference between the dual extruder and my original extruder when I compare
prints but I'm happy with the results and now I've got consistent flow that I
can trust so maybe I can make some more improvements within the slicer settings
but right now the printing about equal so isn't worth it well based on what
I've seen getting that consistent push no matter the temperature is a definite
advantage it gives you consistent flow and therefore smoother prints so I think
it's worth putting on under three spend you consider it's on a $600 printer that
you can put on the sub $200 printer for not a lot of added cost and it's metal
so it's going to last longer than the plastic one that comes on the under
three now having said that I did notice somewhere underneath the gear so heavy
grease under there is highly recommended but overall I think it's an improvement