Good day ladies and gentlemen I'm Tom and
today I want to talk about printer calibration
and especially about the way that you can
screw thing up now first of all let me take
a step back the RepRap project and therefore
pretty much the entire hobby grade 3D printing
market started out as a dive into the unknown
nobody had done it before it was basically
the idea hey this is something that is absolutley
doable now when the patents are gone without
anybody really being afraid of the complexity
of the entire project so people started building
these monstrosity of 3D printers that were
the RepRap Darwin and later the Sells and
the first Prusa Mendel and as they ran into
problems they came up with impromptu solutions
to them many of these solutions are still
being passed around today even though there
were only really intended as clutches to get
your print quality and your parts from unusable
to really bad compared to todays standards
but they still work for that one case so they
must be good right? well not so much one of
these clutches that I would finally put to
rest today is the process of calibrating your
steps per mm setting for any axis other than
the extruder now the usual
process for that involves printing a 10mm
test cube and then adjusting the firmwares
X Y and often also Z steps per mm values
until that cube measures exactly 10.00mm
of course depending on how hard you press
your calipers together now if that doesn't
already sound wrong to you well let me bring
in a car analogy I know some people hate
those but you know haters gotta hate say you
drive a car most of us do and you noticed
that it always seems to pull to the left so
obviously you adjust the steering because
that makes you car drive in a straight line
and that all fine and dandy until you also
noticed that your car now tends to spin out
in corners and completely misbehaves when
it´s raining well turns out adjusting the
steering isn´t all that smart when your drive
around with a flat tire and that´s exactly what
your doing when trying to calibrate a 10mm
cube to exact right size not only is getting
the filament diameter and extrusion multiplier
right much more straight forward option but
your also forgetting that our 3D printers
aren´t really precision instruments that
can even print that accurately just the mechanical
parts ripple, slop, backlash can easily throw
you off by a tenth of a millimeter and if you
compensate for that one tenth of a millimeter
that the 10mm cube is off well guess what
the next time you print something that is
larger say 100mm aka. 4 inches you will have
overcompensated the entire thing and instead
of a tenth of a millimeter you will end up
with an entire millimeter off the dimensions
that you where going for so what i´m saying
here is basically use the ideal calculator
steps per millimeter timing belts and threaded
rods witch are things that usually drive X
Y and Z axis of our printers are made to pretty
tight tolerances they need to work with
every other bit of the equipment that uses
the same profile witch means that the worst
case scenario for the ideal steps per millimeter
setting is it being of by much less than half
a percent to figure out the settings that you should
ideally use head over to Prusas calculator
witch I have linked to in the description
it´s awesome I have linked to it before bit
it´s just so so good of course if you are
not using belts or using an extremely large
printer it might actually be a valid idea
to calibrate the steps per millimeter for X
and Y since like I said half a % is going
to make noticeable difference in larger parts
I have uploaded some files to Youmagine witch
you can use to properly calibrate those setting
without the results being skewed by for example
the extrusion multiplier being off by a bit
so now that we have that out of the way what
are the things about your printer that you
actually need to empirically calibrate? well
it´s not much actually there is of course the
extruder steps per millimeter setting and the
extrusion multiplier witch I show you here
how to get those right then there is the entire
topic of print speed, jerk, acceleration setting
those usually boil down to how much of your
print quality your willing to give up for
faster speeds pro tip if you just can´t seem
to get a print right slow it down like print
at half the speed and you will usually end
up with a much better print and even if not
you get a better look at what else is going
wrong for the basic speed setup thing I made
a long version witch you can watch here other
than that there really isn´t much you need
to calibrate per say of course for many slicer
setting there is only a certain range of values
that makes sense but I would not consider
that printer calibration rather it´s you
who is learning how far you can go with those
settings given experience 3D printer operator
any machine that´s mechanically sound and
well build and they will make it print extremely
well also most slicers now a days will give
you pretty darn nice prints without any tweaking
or calibrating beyond simply mashing in the
basic data about your printer and deciding
how your part should be printed there are
of course concerning about print temperature
retracts and so on but most of those either
work pretty well with the default settings
or you need to be set depending on what filament
you are using so also not really something
that you need to calibrate your printer for
since it´s rather a property of the filament
so to sum things up don´t try to hard to
calibrate every last bit of precision out
of your printer the technology especially
the software aka. slicers is still under heavy
development it´s continuously being improved
for example the new experimental build of
slicer the one with 3 in it´s name so sly 3 r added a feature to compensate for fitting
errors without messing everything else up
basically exactly what the cube calibration
is trying to do just with a difference that
that is how it´s should actually be done right
now that feature is still in beta but by the
time you are watching this video it might
already be in a stable build so that´s it
for today I hope you learned something if
you did please leave a like that really helps
me out mostly because then it means I see people
are actually enjoying my videos also please
leave a comment if you have any questions
left I usually don´t reply to private messages
because those really only help out a single
person if you have an issue you need help
with please at least post publicly in the
comments or preferably in a forum or in the
google plus 3D printing community that way
that knowledge gets publicly documented and
other people who run into the same problem
can at least google for it I´m probably also
going to do another Q&A soon so any question
might get answered there as well one more thing
I´m going to be at hackaday Munich on november
13th so you´re there to come say hello I will
probably be building and hacking stuff maybe
not entirely 3D printing related but close
so as always thanks for watching see you next week
