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I'm using a vise setup here which makes life much easier
when you can because there isn't any other tooling to make (take a look
and come back). Sometimes the
parts I make require me to make some kind of tooling to hold it or bolt
the parts down to before you can machine them. Making tooling takes time
and you're really working on two things to make just one in the end.
When ever you can just use a vise to make something it goes faster.
The pedals are going to be made out of 6061-T6 aluminum and will require
two setups. The first will be the side that faces me that you press on with
your foot and then later I'll turn it over and do other side, called
first and second operation. The size of the block is 2 3/4" X 2 1/2"
X 3/4" thick and I had to machine the two sides
that the vise is holding onto before any cutting is done. I machined
those two surfaces in a manual milling machine first. The reason you
machine the two surfaces before hand is because of the rough saw cut
finish. You don't
want to hold onto a saw cut surface because it might get thrown out of
the vise when you start cutting so this is why you machine them before
hand. The different colored plastic pieces are to cover the holes in
what's called a tooling plate so they don't get filled with chips from
machining. The yellow ones cover 1/2-13 threaded holes and the blue ones
cover 3/4" diameter bushings. We don't use the bushings very often but
we use the threaded holes on every setup (note the four clamps holding
the vise down).
The bushings come in handy if you make tooling to take advantage of
them. For instance, if you had a large plate that held many parts and
by putting the same size bushing into that plate at the right locations,
you can put pins through both of them to line the plate up parallel to
the machine very quickly. This works pretty good if you do it right or
you can just use a dial indicator to make it true. Either way works and
just depends on what you're doing. The small rod that is against the
left side of the block is called a 'work stop' and they work really well
if you have more than one part to machine. In my case I'll be making
three parts because if I mess one up I'll still have two good ones. If I
don't screw one up then I'll have an extra. All you do is loosen the
vise, take out your part, slide in a new piece against the work stop and
then tighten the vise again which puts the new part in the exact same
position as the previous one. Also note the black things under the
work piece. Those are called 'parallels' which are used to raise your
work piece
high enough to be machined. If the part was taller then the vise jaws then
you wouldn't need any. And if the part is shorter than the jaws then
you'd use some that would place your part just above them. Parallels are a way of life for a machinist and I
made every one that I have in many different sizes over the years (which are many). They
also come in handy for all
kinds of things beside what you see here. I use a computer to program
all the parts that go on any of our CNC machines (lathe or mill) and the
program I use is called CAD CAM or Computer Aided Drawing, Computer
Aided Manufacturing. There are all kinds of CAD CAM programs out there
and we use one from MasterCam. The program allows you to draw a two or
three dimensional part drawing (CAD) and then convert that drawing into
special code that the machine can read (CAM). To get it from the PC to
the machine you use a wire from the computer to download the program into the
controller of the machine. Once it's in the machine you need to tell it a
few things before you can do any cutting. For this particular part I
programmed it using the center of the block as a starting point and
after telling the machine what kind of tools I'm using (height offsets),
how many tools (three) and where to start my cut (work coordinates), I'm
ready to start machining. Now this was a quick explanation of what it
takes to set
up a machine like this but never mind all
that, let's get to some machining.
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