Okay, our next video here in the precision measuring set of videos that I'm putting
together for my students and tool usage is hammers and chisels. I joke with my students all the time
that they do not want to be a hammer and chisel technician and what I mean by that is: it's
somebody that is always banging on something or chiseling something away rather than using the
proper tools to get something done so let's talk about hammers here just for a moment in my classes
that I teach here at Weber State University in the automotive department for both manual drivetrain
and automatic transmission I insist that my students use a hammer that has a head hammer
head that is softer than whatever they're going to hit so for example I've got an aluminum housing
right here if there's something I needed to tap or hit related to aluminum I'm not going to use
a steel hammer because the steel will damage the aluminum you always want to use something that's a
little bit softer than what you're going to hit so that you do not damage the part hammers and hammer
heads can be replaced the components themselves cost a lot more than hammers and hammer heads do
so we've got plastique hammers we've got a kind of a rubbery tip here and a little bit harder tip
right here with this hammer here and then we've got brass hammers I've got different sizes of
brass hammers but if you need to hit say steel if you're pounding on something steel for the most
part I want you to use a brass hammer now if you think you want to go grab the steel hammer
instead and hit something that's steel or iron I need you to ask me first if it's okay to do so if
you're going to hit something metal either use a plastic hammer or the brass hammer to hit it
and then sometimes you just don't have a choice you've got to step up to something bigger but
not very often will you use or need in my classes anyway a steel hammer and of course they come in
various sizes and lengths and so on I've probably got 50 different hammers in the drawer over there
Alright now let's talk about punches and chisels uses of punches of and chisels I have both steel
punches and chisels and brass punches and chisels so I've got some great big ones and some smaller
ones I have some specialty punches that are extra long and I have some specialty punches that are
made just for removing roll pins so there's a whole bunch of different style of punches and
chisels I've got another drawer that has much bigger ones in a set but as far as care
and treatment of punches and chisels it's it's pretty much all the same so let's start with the
brass punches here also called a brass drift I've got a long solid one I've got a tapered
one then I have a shorter a solid one every one of these have a knurled end on it that is where
you hang on with your hand and then with you can hit brass with brass with a brass hammer
preferably not a steel hammer you can hit that punch or drift so make sure you're holding on
to the right end you always must wear safety protection in my shop anyway but these all
say write on them to warning wear safety goggles because parts can fly off of the punches
and chisels and so on and of course there are smaller versions of the brass drifts over here
if you need to knock a small part out of an axle or transmission go for the brass drifts
first if it looks like it's going to take more than that talk to me before using a chisel or
punch to knock them out now if you're pounding on something especially with a chisel repeated
pounding without wearing a special anti-vibration glove can over time damage your wrist and your in
your hand and so there's a punch holding tool right here that you can get from snap-on it's
part number PPC5A and what it does is it holds the punch or the chisel for you so you
just stick the punch into it you run this threaded shaft all the way in until it hits the punch
Snug it up good and tight like that and then there's a lock nut right here on the outside that
takes a half-inch or 13-millimeter hand wrench to Snug that up so that as you're hanging on to this
and pounding that it won't come loose and fall out so this has some shock absorption in it also and
if you're one of those guys that sometimes the hammer slips off and hit you in the hand this
gets your hand out of the way you've got a big gap between where you're hitting and where your
hand is so it's less likely that you're going to hit your hand all right all of these punches the
long ones the short ones they're always meant for just driving straight down or sideways or
whatever you never pry on these one way or the other because it'll break them so keep that in
mind also and then these punches over here that are for roll pins never ever use these
as a regular punch these have a little tip on the end of it that will Center itself inside of
a roll pin and keep the punch from sliding off as you're tapping on it so that is a roll pin punch
there's all kinds of specialty punches and chisels available so make sure you're using the right
punch or chisel with safety glasses safety goggles for protection and when you're done of course wipe
everything off put it back exactly where it goes in the toolbox and move on with your next project