so one of the
common tools you'll use for measuring
and also for some marking in the
workshop our calipers now we've got both
direct measuring calipers such as these
three here as well as transfer
measurement calipers just these three
here I'm going to start off with this
little guy this is just a little manual
five-dollar caliper I like to take this
guy to the stockyard if I'm looking for
some used metal and I need to measure
some dimensions on this gives me a quick
idea of being able to measure thickness
or a diameter of a piece not super
accurate it's going to be as accurate as
you can visually see on the tag Mark's
lots of different companies make this
and you can find it in a lot of
different areas this one says it's made
in Germany I can say it slides very
smooth and I've had it for many years
it's been out in the weather gotten wet
gotten muddy and it's held up it's
pretty much brass and stainless steel so
no real worries about corrosion there so
that's the kind of on the cheap end of
what you'll be able to get for a caliper
next up this is a grizzly so it's an
off-brand unit these will work fighting
for the majority of what you need to do
their accuracy may not be a hundred
percent the machining precision may not
be a hundred percent if you if you look
at the jaws here there's a few little
offsets where things aren't perfectly
lined up it's still going to measure
just fine now for the majority of tasks
now my battery is dying on this one also
the display flashes this is a unit that
if you move it too fast or if you take
the battery out and move it it actually
automatically turns on and off and it
does a fairly good job of keeping its
measurements there
and it reads eros fairly well and I
think this was somewhere around the
neighborhood of 1020 dollars on sale so
pretty cheap pretty straightforward but
if you take the battery out move it down
it's it doesn't have an absolute scale
turn it back on it'll give you some odd
number it's not going to be accurate you
can take it back down this to closed and
zero it and you're good to go
now if you have the money to spend I
really do like the the eye gauging
origin Cal this one is absolute so no
matter where I move it with it off as
soon as I turn it on it will give me an
accurate reading of where it's at and
take the battery out move it turn it on
it'll still give me an accurate reading
of where it's at
it reads arrows very well I've not had
any problems with zeroing the quality of
machining is very good on it a lot of
reviewers have compared this to Neda
Toyo and star it and found that this is
just as accurate and just as useful as
those tools costing two three four times
as much so this is a pretty nice little
guy it's both of these that I've shown
here are six inch sorry the other the
other one was actually an 8 inch so this
is a 6 inch that's going to do majority
what you need in the mini machine shop
you can get these on up to 36 inch long
if you really want to spend a lot of
money and have an unwieldy tool not very
good for the the miniature machine shop
so 6 is just fine sometimes you might be
able to get by with the 4 inch as well
the use of these so you can do a rough
slide like this the thumb wheel allows
you to move it slowly and in finding
their adjustments and then if you want
to transfer an adjustment there's a
little locking knob on here that
prevents it from moving so if you want
to keep that adjustment on there you can
this one happens to have a data port if
you want to hook it up to a computer you
can do so
and we have a couple of different ways
of doing measurements with this one is
measuring the outside of a piece such as
we're doing here if it's a smaller piece
you'll want to move it more towards the
back and don't always move out here
particularly on those very sharpened
edge jaws you can end up getting a tilt
measurement like this that's exaggerated
obviously but so you can do outside
measurements there you can use inside
measurement for a hole like this or if
we wanted to measure the bottom width of
that slot and we could get a fairly
accurate measurement on that and then
the last way of using these is as a
depth gauge so the bottom extends out
and you can press down against it to get
a depth reading and that depth reading
will be displayed here another use for
these is inscribing a line this isn't
the most accurate way but depending on
what you're trying to do it may be good
enough I'm just going to roughly set
approximately half of an inch there then
I'm going to hold one jaw against the
bottom and when you use a tip of the
other jaw to scribe a line now that line
is very thin I don't know if you'll be
able to see it on the camera and the
site switch to a closer angle now if we
were to use a marker or a layout die
such as this
then as we scrub it the lane will become
clearer it's still fairly thin and
that's actually to our advantage is we
have a very precise line you can
probably see it now on the camera the
drawback to this as far as why I say
it's not the most accurate is whether
you hold it here or whether you hold it
down here you're going to get different
measurements so how well you can keep
this lined up with the edge of your
piece is going to really depend on on
how well you can make a measurement or a
mark
you can scribe with the insight
measuring jaws as well you can also
there are a variety of other ways you
can use this let's say if you're you're
measuring something so this is point six
three six two five now if I want to zero
that out and for some reason I want to
measure this piece then I can tell the
difference so this one's point six zero
eight five larger than this this other
workpiece so you can do some zeroing
work like that you can also go in the
opposite direction and go into negative
numbers a lot of these will have both
Imperial so inch and metric measurements
the one complaint that I do have about
this is that it doesn't auto power off
and it doesn't auto power on which would
be a couple of nice things even that
that cheaper grizzly unit does auto
power on and off so those are the basic
uses of direct reading calipers now
these units will usually only cost a
couple dollars apiece and you can
typically find things like this at swap
meets or used on ebay as well or if you
buy an import from China
you know you'll maybe spend three or
four dollars and it'll be shiny and new
these are designed for doing the same
types of measurements so if we wanted to
do an inside measurement for example we
can do an inside read of this piece now
at this point we
know what that is we can transfer it or
reference it or we can use another tool
such as our reading calipers or simply a
ruler to get the measurement that we
need off of those points the nice thing
here is this is this is cheap so it's
also you can also get these in very
small sizes in a variety of ranges so
you might be able to get this into a
spot where you can't necessarily get
this you know or to be able to do a
deeper reading whereas on on these jaws
we're going to be fairly limited on how
deep we can go and take an inside
reading if you're using it on the
machine and you happen to damage them
you're only out a couple dollars rather
than this eye gauging I believe was
seventy eighty dollars or so you know if
you're using a start or something along
those lines you're looking at $300 plus
or minus so use these when you need to
we've got the same idea here with
outside measurements this is really
handy for checking so if you've got
something set to where this is a
reference piece and we want to use this
piece to duplicate another piece on the
lathe well now we've got a rough
measurement that we can quickly take and
do while on the lathe and while turning
to get an idea of how close we are or
how much more we need to take off these
are basic friction models there are some
locking models there are some with thumb
screws to adjust them these are all you
know this is inside but you can also use
it to measure outside diameters just by
flipping the blades seen here if you're
measuring a larger inside diameter you
can do that with these and then this is
referred to as a hermaphrodite because
it's designed to measure both an inside
surface and an outside surface so if
you've got a small hole to an edge you
want to measure or a prick mark to an
edge you want to measure you're going to
be able to do that and this tool is
going to be able to do that much more
accurately and then you're gonna be able
to reference it with some other item
so that's just a quick overview again
there are a variety of calipers this is
just the kind of the brief summary of
them you can get calipers that have
hardened sharpen points on them for
scribing you can get so many different
varieties so this is just a quick
sampling of some of the more common
options out there
you