FreeCAD Lesson 12 - Ball Bearing Video Lecture | Mastering FreeCad: Tutorial for Beginners - Design Softwares

very often in free DC ad modeling very
small than just one way to obtain the
desired shape this tutorial is meant to
show you two possible workflows to
achieve a desired shape and we will take
this opportunity to do a small
discussion about differences of a two
workflows and V advantages and
disadvantages of each workflow quite
often in 3d see ad modeling there is
more than just one way to obtain the
desired shape in 3d this tutorial is
meant to show you two possible workflows
to obtain the desired model and we will
talk about the advantages and
disadvantages of both workflows the
version of free kit used here is a 0.16
development snapshot on a Windows 7 64
bit system free cat is under continuous
development and on a nearly daily basis
changes are applied to the source code
correcting bugs and introducing new
features to the software from time to
time varies of some sort of feature
freeze and a release version is being
made the latest stable release at the
point of making this video is the 0.15 4
6 7 1 release which means but the source
code from a beginning received 4670 1
changes now if we take a look at the
Freak at home page and click on download
we will have our official stable
installers and we will have our
development versions for Windows and
make ours excuses you can click on the
link for a free CAD files page taking
you to a github repository where you can
download the newest development snapshot
for Windows and for Mac OS X with
Windows you have a choice of downloading
64-bit snap development snapshot or a
32-bit development snapshot you don't
need to download the source codes so as
I said the latest develop a valley the
stable release re is 0.15 four six seven
one release and if you take a look at
the version numbers here when your
latest development snapshot is at the
moment of making this video with 0.16 6
1 1 4 meaning we are already some sort
of 1,500 commits to the source code
ahead of a stable release a lot of bug
fixes a lot of feature improvements and
there is really nothing negative in
using a development snapshot with the
development snapshot you have a 7z
archive under windows and no X installer
so you just download the archive and
unpack it to a directory of your liking
and if you do not have the 0.15 stable
release already installed on your
computer
a very snow problem under Windows to
install several versions of freak at
parallel you must make sure that
depending on your version first the
64-bit version
you must have installed also the visual
c++ redistributable package for Visual
Studio 2013 and for the 32-bit version
you have to install the 2008 Service
Pack 1 visual redistributable a package
on your system when using Ubuntu Linux
Mint or any other debian-based Linux
distribution you have the option to
change to the daily PPA instead of using
the free code version from the system's
repositories as you can see here on the
download page with a chapter Ubuntu PPA
packages you should make sure that you
do an update and upgrade of your Linux
version to the latest version available
and then you have to add this PPA
address freecad - maintainer x' slash
free cat - daily to your system software
sources either using the terminal or
using the GUI and then you should be
able to update to the latest free cat
development version so let's begin with
our lesson first let's do the ball
bearing with using the part workbench
the modeling strategy will be first
creating the outer ring then creating
the inner ring then modeling the groove
and then adding the balls so let's close
these documents let's create a new empty
document and make sure but the part
workbench is selected first of all we
will add a cylinder and we will apply to
the cylinder with the data tab values
for the radius to be 11 millimeters and
v8 should be 5 millimeters okay we will
switch to EXO metric view we will zoom
outwards to fit all on the screen and
then we will insert a second cylinder
the second cylinder will get as values
for radius an 8 a radius of 9
millimeters and v8 will be left at 10
millimeters we will apply a placement to
the second cylinder in the Direction
minus 2 comma 5 millimeters as I said
before in other tutorials when doing a
boolean operation like this time we want
to do a cut on these two cylinders it is
better to have overlapping contours then
to have coincident faces it is not in
all cases necessary but if you have the
ability please do so it is better so we
will mark the cylinder we will hold down
the ctrl key to also highlight the
second cylinder
we will apply the boolean cut and we
just made the outer ring the next
operation is to insert another cylinder
and to apply to the cylinder a radius of
6 millimeters and 1/8 of 5 millimeters
we will add a fourth cylinder giving the
4th cylinder a radius of 4 millimeters
v8 we will also leave with 10
millimeters bits ok
and we will also click on the placement
tab and click on these three small dots
here to apply a placement in set
direction of minus 2 comma 5 millimeters
we will also now highlight the cylinder
0 0 2 we will press down the control key
and also highlight four cylinders 0 0 3
and also apply a boolean cut here and
we've just made the outer and the inner
ring of the ball bearing so the next
step is to apply a fusion to these two
objects so we highlight these two
objects and apply our fusion to get our
groove we will insert a torus we will
highlight the torus and we will change
radius 1 to be 7 comma 5 millimeters and
we will change radius 2 to be 2 comma to
5 millimeters we will apply a placement
to the torus in z direction of 2 comma 5
millimeters as you can see here the
torus just reached of a desired a
position in 3d space
so then we will highlight the fusion we
will highlight for Taurus and we will
apply a boolean cut and we just received
our groove the next thing is to insert a
sphere to highlight the sphere and to
apply a radius to a radius applied is 2
comma 2 millimeters but when we will
apply a placement in Z direction to be 2
comma 5 millimeters and I will choose 4
by direction I could altered so choose
of X Direction and I will apply a value
in y direction of 7 comma 5 millimeters
as you can see here the sphere just
reached the desired a position in 3d
space here in the center of the groove I
will click on up ok as you have realized
the sphere is a little bit smaller when
the groove if the radius of a sphere
would be the same as the radius of the
groove you would get difficulties in
doing a boolean fusion on all objects
because the geometric or used by freecad
doesn't handle very well
such coincident and in this in this case
Co radial faces on the other hand if you
just want to achieve a technical
abstract representation if you say you
need just an abstract model not a vet
realistic model you could decide not to
apply a groove here and you will just
stay with your two rings and your sphere
here and your array
in this case you would have overlapping
faces and you would have no problem in
doing a boolean fusion on both objects
in such a case this is something not to
be easily decided and you will often
reach such a point of decision in 3d
modeling so we will now highlight our
sphere we will change to what draft
workbench apply our area array and we
will change the array type from auto to
polar we will change the number of polar
copies to be 10 and since of a standard
access for polar array which is inserted
is the z axis we do not change the
values here or any other values we just
take an empty space and freecad updates
our model we will apply a boolean fusion
on these two objects so we switch back
to a part workbench apply our fusion and
here we go we've just finished our ball
bearing now let's do our ball bearing
model with using the part design
workbench the workflow will be similar
but we'll use different tools and the
idea is again to first do the outer ring
the sketch will already contain one half
of the groove and then we will model the
inner ring with the second half of the
groove and when we will model one sphere
and when we will do our array so let's
begin
let's close these two documents let's
create a new empty document switch to a
part design workbench switch to a model
view let's create a sketch on the Y Z
plane let's use the polyline tool let's
start here doing a vertical line which
reaches the horizontal axis when do
horizontal line do vertical line
horizontal vertical again do a right
click to end the tool a poly line now we
have an over constraint sketch in this
case one of these three constraints
should be deleted because this is the
over constraining I will choose this one
to be deleted so I highlight this
constraint here and press Delete on
keyboard or I could also do a right
click here and select delete where it
would have the same effect so now we are
no longer over constraint we are under
constrained so let's do an arc element
from this point here to this point here
okay
now the next thing is to apply equality
to these two lines here and apply
equality to these two lines here so the
next thing would be to select this point
here and select this origin here and
apply a horizontal dimension constraint
of seven comma five millimeters ah the
next thing would be to select these two
points here and apply our horizontal
dimensional constraint of nine
millimeters when we select these two
points and apply an horizontal
dimensional constraint of 11 millimeters
we select the arc to have a radius of 2
comma 2 5 millimeters and we select this
line here and apply a vertical
dimensional constraint of 5 millimeters
now a sketch doesn't look right so let's
go go back what's one step and apply
again 30 millimeters let's change the
value to 20 millimeters my sketch does
look good okay let's try to change 15 10
and the third step five millimeters okay
this is a common thing within freak it
if you apply a change to a value which
is a too big the sketch could up could
end up in another possible mathematical
solution but an unwanted one so as you
have just seen I played a little bit
with the sketch and constraints I went
back one step and applied for scare a
dimensional constraint again and then I
did change but I mentioned a constraint
not in big steps but in smaller steps
and ended up with correct sketch here so
I closed the sketch now and I apply my
revolution the vertical sketch axis we
will use wits ok and here we go so now
we will apply our second revolution to
get the Inga in a ring so let's do a
right click on the revolution here and
either choose height selection or choose
our vertical visibility option so i will
choose hide chilli selection and then
the i will apply a new sketch on the Y Z
plane I will just draw profile like I
did before doing a vertical line here or
is on to one here vertical one here or
horizontal line here and another
vertical line here then I will create my
arc from this point to this point I will
apply equality to these two lines I will
apply to equality to these two lines I
will apply my radius here of - Omar -
five millimeters and I will then apply
here my horizontal dimensional
constraint of four millimeters I will
apply here a value of six millimeters
I will apply here a horizontal
dimensional constraint of seven comma
five millimeters and I will apply here a
vertical dimensional constraint of five
millimeters and we are all set
I will close the sketch I will do my
revolution around the vertical sketch
axis I will choose okay I will toggle
the visibility of the outer ring here
and as you can see we just obtained our
two rings with our groove so let's do a
sphere we highlight these two
revolutions apply a right click and
toggle the visibility we click an empty
space to deselect everything we apply a
new sketch to a Y Z plane we click on OK
we zoom a little bit in we will do our
arc starting here going from here to
here we will create a line from the end
point of the arc to the other end point
and applying a vertical dimensional
constraint we will then
apply a another line from this endpoint
here just going down to the horizontal
axis and we will toggle the line to be
of construction type we will then choose
the midpoint of the arc and this line
here and apply symmetry we will apply a
radius to the arc of 2 comma 2 5
millimeters we will apply a distance
here of horizontal dimensional
constraint of 7 comma 5 millimeters and
we will apply our vertical dimensional
constraint here of 2 comma 5 millimeters
and in this case the outer constraining
did not work
we will constraint this point here to be
on to the horizontal axis now we are all
set we close the sketch we do our
revolution but we will not choose our
vertical sketch axis we will choose
sketch x is 0 okay now we have our
sphere here we will also apply our array
and we can't apply the polar pattern
feature because the polar pattern
feature is only meant to be applied to
pets or pockets within a part design
workbench we have one single solid
and we want to apply a some sort of an
array to it so we have to use the array
tool from the draft workbench so we a
highlight the revolution here we switch
to the draft workbench and we do our
array we switch again to polar type we
change the number of copies to 10 and
here we go we talked about visibility of
these two evolutions and we could now do
a fusion on all these free objects and
so we have also created for ball bearing
using several sketches so as you can see
both workflows have FET advantages and
disadvantages if you will change later
one of the dimensional values for
example it is in my opinion a little bit
easier to just search for a right sketch
and then to enter the sketch in edit
mode and apply a new dimensional value
to one of the constraints then to search
in the part workbench for the
appropriate primitive and change its
placement or whatever but of course it
is easier to apply
but ref move and rotate commands to a
part created within the part workbench
with a part design workbench you have to
apply the move and rotate commands to
sketches you used namely to the first
sketch EF used
and of course with party sign maybe you
will take a little bit longer speaking
of the time needed to do a model but on
the other side if you use four part
workbench you noticed with the heads
sometimes to switch to a draft workbench
or to the sketcher workbench maybe and
to use some tools from where so this is
also a little bit more work as I said
before there is no single and no no only
real one way to do a model in 3d space
where often more than one ways to do a
model and depending on the purpose of
your model and the shape of your model
maybe you will be forced to use a
specific workbench for your purpose as
you have seen we did switch workbench is
quite often and every time we used the
pulldown menu on my personal system I
use a little trick to speed up switching
between work benches now since every cat
is programmed mostly in Python if I also
enable per view a Python console um and
let's say if I will switch to a party
design workbench you can see in the last
line of a python console a Python
command used to activate the workbench
part design workbench so I did record a
macro using the record button switching
just to one of the work benches and when
I stop the recording and for example the
macro used to
we'll switch to my sketch your workbench
does look like this I use respond here
execute macro I select my macro which is
named here WB underscore sketcher a dot
FC macro and if I go to edit you will
see that it just contains one line
activating the workbench sketcher
workbench the next step was to use the
tools customize menu to go to the
category macros and to apply to each
just recorded macro in my case I
recorded for macros to switch to the
sketcher workbench to the part workbench
to the part design workbench into a
graph workbench I applied here a menu
text a tooltip sort of short help and a
keyboard shortcut and I also applied an
icon to this macro the next step would
be to define a global toolbar so I'm
into the toolbars and select it here
from tool from a drop-down menu the
global section and when I created with
new a custom toolbar and the custom
toolbar
contains now all these four macros and
if I take this box here to make the
custom toolbar show up and I click on
close I have to restart freecad to apply
the changes
so after restart of freecad my custom
toolbar shows up and within with
preferences I have set the initial
workbench to be activated to be let's
start up the complete workbench to make
sure but everything I have set up as
user customization will be edit to free
kit and so this is my custom toolbar
showing up in every workbench and I
quickly can now switch to the Sketchup
workbench by clicking on the icon here
just switch to the sketch about bench or
using a designated keyboard shortcuts so
while speaking about different ways of
doing a C ad model and speaking about
efficiency and parametric and history
and things like that
well what about adding a bonus lesson so
let's jump aboard our time machine and
head right back to the first lesson we
did return this cube at the time when
you did the Turner's cube as a first
lesson
the main point of the lesson was to get
you familiar with a pet and per pocket
function and so some users asked a one
of the first obvious questions is there
a way to duplicate or reuse the sketches
to get a more efficient model of course
this is possible we learnt during the
lessons that you could reuse the
sketches by copying them for
examples of a clipboard and inserting
them somewhere else and you can also
reorient the sketches and attach them to
our faces this is possible but as you
can see we used a lot of pockets and
most pockets all have the same
dimensions the big pockets have the same
dimensions and the middle pockets as
well
and speaking of an efficient parametric
3d model this way of modeling is not an
efficient modeling but which is quite
common after some time if you learn new
tricks and maybe the software did get
one or two new features if you look when
at your CID models you will not be the
first one to say oh dear what did I do
where let's throw the model into a
digital trash and redo everything again
so if we will set up a task saying let's
do a Turner's cube using the part design
workbench and use a parametric modeling
using s few features and s few
dimensions as possible this would look
like this so let's close this document
create a new one
switch to the part design workbench and
the first thing we did was creating a
new sketch on the XY plane we created a
rectangle we applied symmetry to these
two points in regard to our y-axis and
we applied symmetry to these two points
in regard to the x axis then we applied
equality to these two lines
and we applied a dimension of 200
millimeters to this line here there's
nothing to optimize here so the close
the sketch we do our pet we do it
symmetric we change four dimension value
to 200 millimeters okay the first
operation were pet there's nothing we
could do to optimize that there's only
one thing which is missing at the moment
we would like to be able to set in this
case an equality constraint or something
similar between the dimension used in
the sketch and v8 of the pet we defined
with 200 millimeters and being symmetric
at the moment this is not possible but
I've read in the forums but with a 0.16
development snapshot something called
expressions is introduced and if I
understood all the postings were correct
now this is also possible to set up
relations between constraints in
different sketches and constraints used
on operations like this
so my next thing would be our pocketing
we would not use several single pockets
to make an efficient parametric model we
will use a revolved profile and an array
and then doing a boolean cut and using
clones to get a rest two pockets
so now let's toggle the visibility of a
pet apply new sketch
in our case now - oh why is that plain
let's use the polyline tool start on the
vertical axis here go upwards and then
apply our three pockets
like this we now have an over constraint
sketch so we will delete this constraint
here we will apply equality to these
three lines because this dimension we
will set up with 25 millimeters and this
dimension we will also set up with 25
millimeters so now we will set up radius
or for free pockets the biggest one
being 93 comma 75 millimeters where next
one is
oops I selected three points now let's
select this point and this point
applying a horizontal dimensional
constraint of 62 comma five millimeters
and let's select these two points
applying in a horizontal dimensional
constraint of thirty one comma two five
millimeters
let's it we close our sketch we do our
revolution and here we go the next thing
would be to switch to a draft workbench
have revolution highlighted and then
doing an array make sure we array is
highlighted change the array type from
auto to polar change the number of polar
copies to four and change the axis to be
not with z axis in this case the excess
of over array of polar revolution if you
will call it like that will be the x
axis so let's change your value for the
x axis to one and change the value from
the z axis to zero back now we will have
something like this
we will set the fuse parameter to true
to obtain not for overlapping solids but
one single solid okay so my next string
is that we will highlight this
revolution here and do a draft clone off
we highlight revolution we will use the
clone of revolution and do a placement
we will change replacement to be
incremental we will choose / y XS s
rotational axis and we will apply a
rotation of 90 degrees we will then
clone the revolution again this time
applying to the clone an incremental
placement we will change as we change s
rotational axis with y axis but in this
case we will apply minus 90 degrees we
click on apply choose okay and which is
one of the limits of free ket at the
moment it is of importance at which
point in the history of a part you did
do the clone if I will change the sketch
or the revolution at some point the
clone will also change but if I will add
something to a revolution the clone will
not change because the clone was made in
a point of history of a part when only
the revolution existed will fir sketch
so let's select the array but two clones
let's switch to the part workbench and
do a fusion of all these solids let's
talk about visibility of a pet let's
select the pet and the fusion apply a
boolean cut and we have made our turn
askew as you have realized we only used
200 millimeters here as dimension 200
millimeters with a pad and our few
dimensional constraints with this one
revolution so this would be a very
efficient way to use for parties line
workbench and design a curl at earnest
cube the turn is cube is parametric you
can change your values and this history
based you can go back in the history of
creating the part well with that being
said we have reached the end of today's
lesson I hope I did show something
useful and you had fun learning new
tricks by free CAD as usual feel free to
leave any comments critics remarks
requests or something like that related
directly to the video here on YouTube or
if you have more complex questions feel
free to rig it the register for free
with a forum on free card web blog and
upload snapshots and post your questions
there I hope you will enjoy working with
free cat and well maybe see you on
another video bye