6. Molding and casting¶
This week I designing a moldable design, and casting to produce the final piece.
Group Assignment¶
in the group assignment we gathered all the safety instructions for all the materials used. Here is a link for all the information.
Individual Assignment¶
For the Individual assignment I decided to make a double pendulum, that’s two simple pendulums connected with a free joint.
so first I needed to create a design so I can mill it in a wax cube so I can obtain a cast that I can pour my molding material in.
here is briefly how I designed it
I made a sketch of the shape I want
then I added text (dpv1 stands for double pendulum version 1)
then I extrude the sketch to the hight I wanted
then I copied the first part without the text so it wont interfere when swung
for the files here is both STL and F3D
after I finished the design I sent it to the software to perpare it to the milling machine
then choosing the type of milling
then choosing the tool path
preview the finale piece
send design to the milling machine to start cutting
calibrating the z-axis and start cutting
then I started to cut and melt the silicon to make the cast I will be pouring my material in.
I used these big cubes of silicon
then cut them to small pieces
then I melted them
then I poured the melted silicon in the piece of wax the I milled
after the silicon cooled down and solidified, I prepared the the resin to pour it, for the ratio between the resin and hardener check the group assignment I used GR Resin
after the resin solidified
at this point I faced a problem that the holes I made were closed by the resin so I just drilled them.
as for the assembly I started by making a stick with some kind of stopper at the end so the pendulum don’t fall.
and for the pendulum it self I used screws and nuts
here is all the parts I used
and finally the double pendulum in action
Simulation¶
From my previous work outside FabLab, I have made a double pendulum simulation (see about section), so I decided to simulate the pendulum I have made.
first I weighed and measured the length of my pendulum
without damping¶
with damping¶
damping constant = 0.6
of course because the length is too small the quality of the simulation is low.
the code is in fortran90 language, here is the code of the simulation,after running the code use Gnuplot to animate the results using the plot script ps0, also download this file ps so the script runs.
in ps0 comment and uncomment the gif command with “#” as needed, and be carful of the range specified.