- Hello and welcome to this Haas Tip of the Day.
Now, we know what this is.
It's an ER collet, and it seems like
half of the rotating tools that we use
in our mills and our live-tooling lathes
are being held in one of these collets.
That makes these a critical part
of our manufacturing process
and something worth understanding.
Now, there are lots of moving parts
in our ER collet holders,
and each one of those pieces can either make our tools
cut better or worse, so stick around.
(bright music)
This is an ER collet tool holder,
the most-used tooling system known to man.
Now, they've seen constant improvements
since they were first introduced by Rego-Fix in 1972.
They've since become a den standard.
Now, I think they're so popular because one size holder
can hold an entire range of tools
just by exchanging the collets.
Other types of holders, like shrink fit holders,
can only hold one particular size of tool,
meaning that you need a whole bunch of different holders.
That can get expensive.
When we set up a tool in an ER holder,
we're looking for two things.
Number one, we wanna maximize the clamping force
transferred to that tool
by the collet and the collet nut.
And number two, we're looking for
the minimum amount of runout or TIR.
When I say TIR, I mean Total Indicator Reading.
This is a complete range of runout, or wobble,
measured at a given point on your tool.
Now, we can measure this in the machine
with a mag base and an indicator
or on an offline tool pre-setter.
A strong tool clamping force dampens vibration
allowing us to run at higher RPMs
and it lessens chatter.
And a tool that's running true with very little runout
will wear more evenly,
lasting longer and giving us better parts surface finishes
with all of the flutes doing the same amount of work.
Wobbly tools can also cut oversize,
which can put us out of tolerance
and force us to scrap out our parts,
so we've got some really good reasons
to set up our ER tools properly.
ER collet systems come in different sizes
and different levels of precision,
but in a nutshell,
there are eight different sizes of collets,
there are four different styles of the collets themselves,
and four different styles of collet nuts.
And it doesn't take forever to learn this stuff.
We're going to start with out collet holders.
ER holders come in different sizes
based on the collets they can hold,
ranging from ER 8 all the way up to ER 50.
Now, this is driving some of you crazy.
I'm only showing you seven different collets here.
Well, that's because I don't have an ER 50 collet on hand.
I'm not going to buy one just for the video
because I don't use them every day.
Here, better?
(trombone music)
Our ER numbers can be found
just by measuring the holder cavity.
If we measure 16 millimeters in diameter,
then we've got an ER 16 holder.
32 millimeters, we've got an ER 32.
We can also measure the outside of our collets, as well.
We'll choose our ER holder
based on our tool's shank diameter
and the reach and clearance that that tool might need.
A tool in this holder is gonna cut better and faster
than a tool in this holder.
The only time I'd want to use this instead of this
is if I need the reach or the clearance.
Now, sometimes we don't have a choice in the matter.
Sometimes we've gotta get creative because our part,
or our fixturing, demand it.
Now, here's a chart for you, showing the maximum tool sizes,
that's shank diameter,
that can fit in any ER holder class.
Now, lots of tooling vendors make collets
that are just slightly
larger than the numbers we've shown you,
but these are great generic values.
Once we've decided on our tool and an ER holder class,
it's time to choose our collets and our collet nut.
Now, this is really important.
Our decision here is going to have a big impact
on how those tools run.
Here we've got four different styles of ER collets for you,
each with its own special use.
Right away, you can see a difference
between these four collets.
We've got our 16-slot standard collets
with a one millimeter collapse range.
We've got our 12- or 16-slot high-performance collets.
Many of these collets come with colored bands on them
to set them apart from their standard collet brothers.
We've got our tapping collets.
Those have eight slots:
four on the top and four on the bottom.
And you can also see a square receiver in the bottom of it
which'll match up to our taps to keep them from spinning.
Then we've got our sealed collets.
These channel the coolant through our
through-spindle coolant tools.
We can use a standard 16-slot collet for just about anything
from drills to reams to end mills.
Now, one of these standard collets
is good for about 10 microns of TIR,
or about 4/10 of a thousandths of an inch.
Most are better than that, though.
We'll use our high-performance collets
for detailed features or performance tools,
or just when we wanna extend the tool life
of a tool for production.
But then again, when do we not want longer tool life?
Okay, these high-performance collets
might have five micron of runout,
or 2/10 of a thousandths of an inch.
With some, like this Parlec ERos system,
built to hold just 2 microns.
That's 1/10 of a thousandths of an inch of TIR.
That puts this holder on par with most hydraulic
and shrink fit holders
but with the adaptability of an ER collet system.
Now, there are a lot of different brands
of high-end collets and collet holding systems
out there, so check around.
Here's my 12-millimeter end mill,
and from the chart that we showed you earlier,
we know that it could fit into an ER20 holder
but we've decided to go with the much larger ER32 holder
for a better hold.
Now let's take a field trip and grab that collet.
So this is one of our many vending machines
here at the factory,
and I can look on my chart here and I can see
that my ER32 collet for a 12-millimeter end mill
is in slot number 36.
So I can just issue that out.
And you can see right here on the end of our box
it says 12 for my 12-millimeter end mill.
But is this a plus or minus number?
Can we go bigger than that with my tools?
Smaller, how does this work?
If we open up the collet and we read it,
you can see that this collet is good for a tool
that's between 12 and 11 millimeters in diameter.
It's written right on the collet.
Now, looking at our chart,
it looks like all of these collets
are good for a 1-millimeter range.
Here's how these collets work.
They are meant to collapse, not to expand.
If you find a collet that says 12 on it,
it's not good for anything bigger than 12 millimeters.
It's good for 12 to 11, even if it doesn't say it.
Well, let's go back to the bench.
Now we want to use...
(laughs) it was really loud over there.
It's much quieter over here.
We're gonna use the tightest collet available
for the tool that we're gonna use.
This is gonna give us
the most tool-to-collet contact area
and the best runout.
Now, we're using a 12-millimeter tool,
so we're going to use the 12 to 11 collet
and not the 13, 12 collet.
Now, a lot of high-precision collets
are actually on-size collets.
They're meant to be used with a certain size tool.
Some collets, high-precision or not, might only have
a 1/2 millimeter collapse range.
So always look at the collet,
make sure you read the number,
and you understand how that works.
But what if my tool is just 10 thousandths of an inch
bigger than my collet?
I can still make it fit, right?
No, you can ruin your collet.
(dangerous music)
Now, we have our tool, our holder, our collet.
Now we need our collet nut.
And these nuts come in four basic flavors.
We've got our flush nut, our low-friction nuts,
our coolant nuts,
and our mini-nuts.
Now, there are lots of different types beyond this
but these are the basics.
Flush nuts are the least expensive,
but they're strong and they're great for general use.
They're called flush nuts because the collet
comes flush with the face of the nut, which is great
if you don't wanna have to stick out your tool
any further than necessary.
Low-friction nuts make use of bearings, bushings,
or special coatings to reduce friction
on that 30-degree surface where the top of the nut
makes contact with our collet.
Now, this helps us to give more transferrable torque
right to the tool.
This makes a difference.
We can actually get 50 to 100% more tool-holding force
directed right onto our tool.
This makes a big difference when machining.
If you have a ball-nosed tool and an ER collet
and I had my choice between a standard flush nut
or one of these friction-bearing nuts,
I am definitely going with this nut.
Every manufacturer has their own version of them.
This is a Parlec power nut.
You've got the Rego-Fix ERBs,
you've got the Lyndex bearing nuts.
So check with your manufacturer.
You definitely wanna know the difference between this nut
and this nut.
They also require different torque values.
And behind door number three are our coolant nuts
which make use of these coolant disks,
making them ideal for through-spindle coolant tools.
Now these coolant disks, or sealing disks,
come in 0.5 millimeter ranges
to perfectly seal for every tool size.
When we load up these disks, they just snap in
from the underside of the collet.
Now when we load our tools,
we want to load those from the top side of the collet.
If we load them from the bottom up,
they could damage the O-ring on our disk.
Now, low-friction nuts have better tool holding power
than a coolant nut or even a flush nut.
So what if I wanna run TSC through a spindle coolant
but I want all the tool-holding power
of the power nut?
You can do this without a coolant disk
if you use one of those fancy sealed collets
that we showed you earlier.
In fact, there are collets out there
like this Jet 2 collet from ISCAR
that can turn any tool into a TSC tool, kind of.
The collet is sealed, but special grooves have been added
to direct the coolant right at the tip of the tool.
Now, you can run TSC through a standard collet as well,
and it'll help out quite a bit.
These specially-designed collet nuts and collets
are just better at getting the coolant
right where it needs to be.
Finally, we've got our mini-nuts.
Now, these function in much the same way
as a typical flush nut,
but they have a smaller diameter.
All of these collet nuts here are for an ER16,
but you can see that our typical hex ER16 nut
is just under 28 millimeters.
A good nut.
These mini-nuts are under 22 millimeters
for an ER16, so I can reach into spaces
that I couldn't otherwise.
That makes these type of extensions with mini-nuts ideal
for my live-tool tooling.
With all of our components ready,
it's time for us to assemble everything.
We need to keep our collets clean and dry
when we assemble things.
Now, you can use a degreaser or even alcohol
to clean off grungy collets.
And now, we're using a brand-new collet,
so it has that thick, waxy rust preventative on it
that we're gonna have to get rid of.
We'll want to clean off our holder
and our collet nuts as well.
Now, I'll use a lint-free cloth
with some rust preventative on it.
I use Castrol Rustilo.
That's what we have here at the factory.
And I will go ahead and wipe down the threads.
Now, this is why I do that, and I don't do it all the time.
Earlier we showed you this high-performance collet.
This is a five micron collet, a good collet, from Parlec.
And it's got a high polish on the outside wall.
They didn't spend quite as much time on the ID polishing it.
And there's a reason for that: because they want the outside
to slip nicely against the inside of the holder,
low friction, but they want the ID of the collet
to have more friction, a rougher surface
to hold onto our tool.
This is why you don't want to soak an entire collet with oil
and leave them that way.
That's great when they're on the shelf.
If the ID of this collet is just soaking with oil,
it's going to have less hold on your tool,
and your tool will be more likely to pull out.
But when they go into our holder, we want them
typically clean and dry.
If you find a damaged collet or a collet nut or holder,
get rid of it.
You don't want that thing in your shop.
It'll work its way from tool holder to tool holder,
ruining everything you've got.
So if you see a bad part,
don't set it aside for later.
Get it out of your shop.
Most collets have an eccentric extractor ring,
a lip that helps pull out the ER collet during disassembly.
This can make them hard to put together
or take apart if you don't know the secret.
Most collet nuts have a mark on the bottom of the nuts,
or on the rotating friction ring,
that shows us our pivot points for loading the collets.
Tilt the collet, load it at an angle,
tucking it behind that extractor lip,
then tilt it up.
If it is too difficult,
we may be tilting it the wrong way.
Rotate the nut in your hand until
the collet just snaps in.
But we never, never, never, never, ever set the cullet
onto the holder and screw the nut on.
We can break our nut and we can damage the collet.
Ideally, when we load up a tool,
we're gonna be holding on to it
by the entire length of the collet.
Or at least, two-thirds of that collet.
Now, you can use a tool, the weldon shank, but you may
lose some clamping force.
But never let the gap on the weldon shank tool
hang over the edge of the face of the collet.
And if running a drill, never clamp on the flutes.
One last thing about loading up tools in an ER collet.
Right here in the center is a back-up screw.
If you drive your tool all the way up against the back of a
holder and then tighten your collet,
it could force your tool to wobble, causing us runout.
You don't want that.
So, normally we don't want the tool set all the way
up against the back-up screw as we tighten that nut.
We want to leave some room, and then we can come back later
and gently move that back-up screw up against the
back of the tool, if we really need to.
This has an Allen wrench in the front, and we can
reach it with a flat-blade screwdriver from the back
through the TSC pull stud, now I said TSC.
Now, take a look at this guy.
Look how small the hole is through this
particular back-up screw.
If you're running a TSC drill that needs lots of
volume of through-spindle coolant,
you're better off removing this back-up screw altogether.
All it's doing is choking your coolant flow.
When I load up tools that other people
have assembled, I always look at the gap,
the slots, in the collets.
If you don't see any visible gaps in the collet,
then the last set-up person might have chosen a collet
that's too large for the tool.
If the gaps are really big, they might have chosen
a collet that's too small for the tool.
Either way, take everything apart, make sure you're
using the right sized collet,
clean everything, and put it back together.
Now if you see a collet where all the gaps are uneven,
something's gone really bad, OK?
They didn't clean or assemble the tool properly,
or they over-torqued this nut,
causing the collet to twist badly.
In that case, take everything apart, and also check
to make sure that your nut is not cracked.
That's why it is always a good idea to use
a torque wrench to tighten down those collet nuts.
Even here in our own machine shop, we're using
torque wrenches with adapters
to tighten all of our collet nuts,
doesn't matter what style.
Now we mentioned earlier that low-friction nuts
take less torque to tighten than a standard flush nut,
and many nuts take even less torque than that.
So here's my list of some generic torque values
that you can use with most holders.
But if you use these values, you might be leaving something
on the table, they might not be perfect for your tools.
In the description of the YouTube version of this video,
we'll give some links to different tooling manufacturers
with their actual torque specs.
There're some great websites out there
for each manufacturer, check em out.
The torque specs from the manufacturers are based
on the largest tool that'll fit in that collet.
Now as we use smaller and smaller tools, we'll wanna use
less and less torque.
Essentially, you'll wanna take it easy on tools that are
smaller than about four millimeters or 3/16ths of an inch.
Now if you're tightening up those tools by hand,
you'll wanna use one of these slotted wrenches.
We've got spanner wrenches as well, I prefer the slotted
wrenches, they give you a better hold on the collet nuts.
They come in all different sizes.
We also have these non-slip versions,
these are really popular and an AX
wrench for our live tooling.
And we've got our Castle wrenches, our ERM wrenches,
which we use on mini-nuts, we don't need much torque
on these guys at all.
Remember those polished collets that we showed you earlier?
They were great because they reduced friction between
the collet and the nut in the holder.
If I've got a corroded collet, then I'm not gonna
throw it away, typically, right, 'cause I'm cheap.
I'll take a Scotch-Brite Pad or a light abrasive
pad, and some rust preventative and I'll
clean off that surface rust.
But by doing so, I'm making the surface of
my collet more porous, which means it's just
more likely to rust in the future.
Not only that, but with that more porous surface,
we're gonna add friction into our ER system
which is bad for runout.
So I keep em, I use em, but I don't
use em on tight tolerance tools.
Which brings us back to rust preventative, right?
You wanna come up to the collets in your rack,
we're using a rack so the collets don't
damage each other, but we wanna come up to these
collets every now and then and wipe them down
with a rust preventative.
This is kinda the take away of this video:
make sure you keep your unused collets well-oiled
so they don't get damaged with corrosion.
Make sure that you're using the right
collet nut for the job, whether you're using a
low-friction nut, flush nut, coolant nut, and make sure
those things are clean and dry when you assemble them right?
Or maybe a light sweeping of oil around the outside of your
collet or on the threads.
And torque those collet nuts as necessary.
That's it.
We'll be looking forward to seeing you next time
in the next Haas tip of the day.
(bright electronic music)
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