Okay, the next style of dial indicator base and dial indicator I'm going to show you that we
use here occasionally in the transmission lab is from Starrett this is a magnetic base but
it's made for flat surfaces only it's a Starrett model number 657AA and I'm using
a dial indicator number 25611J. now there's a couple of unique things about
both of these that both the base and the dial indicator that we need to talk about the dial
indicator first if you use this one notice it's in the box it's not just flopping around in the
toolbox we've got a foam cover to take that off or take off the foam cover and then an
insert where this very expensive very precise dial indicator sits now what's so fancy and
precise about this dial indicator well this dial indicator is made for very small measurements this
is made to measure in ten-thousandths of an inch measurement so the other dial dial indicators
that I have measuring one-thousandth of an inch this would divide each one-thousandth of an inch
into ten smaller portions and that is a ten thousandth of an inch so a very precise very
expensive tool it has jeweled movement with Ruby industrial Ruby bearings for long life and high
accuracy the plunger only moves 1/5 of an inch - hundred thousandths of an inch is all this
plunger moves so the more precise they are the less plunger movement there is so we are going
to use this high precision dial indicator to measure run out on some intermediate shafts in
a transmission so I've got two identical intermediate shafts here out of a Toyota Tundra
AB60F transmission and the specification for run-out is one ten-thousandth of an inch right
here in the center so anything more than one ten thousandth of an inch and this shaft needs to be
replaced all right I've got a set of V blocks here that we are going to use to measure the
run-out of a transmission intermediate shaft these V blocks are a matched set they're both
stamped with the number 1 1/4 so if you have multiple sets of V blocks you can or you should
make sure that they both have the same stamping on them as you're taking measurements so we want
to measure the run-out right here on the center of this intermediate shaft so I'm going to take
this magnetic base put it right here on the V block and turn on the magnet all right now use
the thumbscrew here I think I need to turn that around so this rod holds the dial indicator in
place can't come over here near where we need to take the the measurement itself notice the
rod is too short to get over here to take this measurement if with a dial indicator on it so
we'll turn the shaft around in the V blocks and now where we are going to take a measurement
is right here so I'm going to just kind of lock the small dial indicator based rod in
place notice it has a small rod on a large rod now this clamp is a little bit different as far
as how we connect the dial indicator to the clamp self it has this little threaded holding fixture
right here it will um thread and then the back of the dial indicator right here has this hole
in it, we're going to position the hole in the back of the dial indicator over that threaded
shaft and then screw back on the little thumb screw portion that holds it in place so the dial
indicator is attached by the back of the dial indicator not by a plunger base like we did in
my other videos on dial indicator usage so we've got the hole right here that goes with
the small rod get that small rod back over here I'll take this whole line it up just like that
and get it pre-positioned to where it's just about ready to go on to our intermediate shaft
like that now obviously the the plunger is over here and the intermediate shaft is back here I
can take this off and turn it around or I can move the magnetic base to the other side of the V block
and lock it in place and then just play with the thumb screw positioning of the rods that
hold the dial indicator in place I'm going to flip this one back over that'll get me closer to the
surface that I want to measure so about right there is where I want this clamp approximately
except we want to extend the rod length enough that our plunger can be pre-loaded right there so
lock everything in place just like that and now we are almost ready to take a measurement we
have an adjustable dial here on the outside to zero the dial indicator we have a little thumb
screw right here to lock or loosen that outer dial so that we can zero it each of the little
tiny marks on the base of that or on the face of that dial indicator indicates one ten-thousandth
of an inch each of the numbered marks indicates one-thousandth of an inch all right I've got the
dial indicator plungers sitting on the machined surface that I want to measure I've got the other
two machined surfaces sitting in the V blocks and I'm going to rotate the shaft hopefully without
causing a disturbance in our reading here so let's zoom in and let's zero that dial indicator
okay I've got the dial indicator zeroed it's okay if it moves just a tiny bit as we do our initial
rotating of the shaft with increments this small sometimes the shaft will realign itself in the V
blocks but let's take a look at how much run-out we get in this particular shaft so I'm rotating
so each little tiny mark as I said was a ten thousandth of an inch we are definitely more
than 10 thousandths of an inch so this shaft is no good and that's because I took it over
to a press and bent it on purpose for this demonstration so this is a high precision
10 thousandths of an inch capable measuring dial indicator and a flat magnetic base mount
so I've now shown you in four different videos four different style of dial indicator mounts
and usage and precision of dial indicators you don't need to run out as a new technician and
buy a $300 dial indicator you can start with the real cheap stuff if that's what you need to do
just be aware that the precision and life of that precision varies greatly from one brand to a next
to the next with some of that real inexpensive knockoff garbage that they sell at some cheap
tool stores so beware they are not all the same once you're finished taking a measurement with
this tool make sure that you take it apart and put it back in the boxes where it goes I do not
want this tool left out on the workbenches it's too expensive, too precision of a tool to be left
out so make sure that you Re-box it and put it away when you're finished with my classes