(jazzy music)
Marc: Welcome to Episode 13
of The Wood Whisperer video podcast.
^I'm your host, Marc Spagnuolo,
^and today we're going to take a look
at one of my favorite stationary power tools,
the band saw.
(jazzy music)
I use it for re-sawing large boards,
ripping long stock, making my own veneer,
and cutting complex curves,
but on today's show I'm going to show you
how to set up a new band saw
like we've got here or tune up your old band saw.
With the exception of the initial cleaning,
the process is pretty much the same for both.
Let's assume you've wrangled your new saw
into position and you're ready to get started.
Just plug it in and start cutting, right?
Definitely not.
You've got a little bit of cleaning to do first.
Most manufacturers ship their tools
with a plastic sheet over the cast iron surfaces.
Under that sheet is a rust-preventative goo.
The best way to remove that material
is to use some sort of a solvent.
Kerosene and mineral spirits are
most commonly recommended.
Here I'm using mineral spirits.
I pour on a liberal amount of mineral spirits
onto a rag and start wiping.
It takes a while, but eventually
you'll be rewarded with a nice shiny
cast iron top,
but it won't stay that way for long
if you don't add protection.
If you do some Googling,
you'll find tons of information about
rust prevention on cast iron surfaces.
Here's my favorite method.
After the mineral spirits flashes off,
I spray a good amount of product
^called T-9 Boeshield.
^This stuff was created by the Boeing Company,
and has a great reputation amongst woodworkers
for this exact purpose.
I use a clean rag to spread the T-9
and massage it into the surface.
I then let the surface dry overnight.
The next day the surface will be a bit tacky
so I buff aggressively using a clean rag
until the tackiness is gone.
At that time it's a good idea to add
a little bit of wax.
This will further protect the surface
as well as make it nice and slick.
My favorite wax for this job
^is Renaissance Wax.
^A little bit goes a long way.
Now the next thing we should do
is make sure that the wheels of the band saw
^are coplanar.
^Without coplanar wheels, the blade
^can drift off course,
and actually prevent us from getting
consistent cuts.
The idea is to run a straightedge
across the top and bottom wheels
to see if they're in alignment with one another.
On some saws this is easier said than done.
On my saw, for instance, I'd have to remove
the cast iron table top.
I had a hernia when I was five,
and I'm not looking to get another one at 30.
So I don't think I'm going to remove the top.
One alternative would be to secure
equally-sized wood blocks to each wheel.
The blocks would have to be long enough
to extend past the table,
and then you could place your straightedge
across those blocks to check for coplanarity.
To me that sounds like it's a little bit
too much work.
So since of got quite a bit of faith
in Powermatics quality,
I'm going to do all of my other adjustments first,
and if the saw still doesn't run true,
then I'm going to go through
the table removal procedure and check the wheels.
If you can check your wheels,
and you do find that they're actually not coplanar
you can easily shim the wheels out
using small washers.
Now let's turn our attention to the blade.
It's a good idea to wear gloves
whenever you handle a band saw blade.
They're sharp and they're very awkward.
This may sound crazy, but you want to make sure
that there's no animals around while you do this,
or children for that matter.
A while back I accidentally left
one of my blades on the ground,
and my dog ran by got spooked,
and took the blade with her.
Unfortunately it just got caught
on the back of her paw and then it fell off,
but it could have been far worse.
I can't even imagine what would have happened
if it went around her neck.
So be careful.
Now that I've got the blade out of the band saw,
it's a good time for me to show you
a quick tip for how to fold
this band saw blade up.
It's a lot harder than it sounds,
and if you've ever tried it,
tried to get it into a nice little coil like this,
you know what I mean.
It's not that easy.
I've got a foolproof way of doing it.
Make sure you've got your gloves on,
and your eye protection on,
and check it out.
I grab the blade at about the eight
and four o'clock positions.
So the majority of the blade is above my fingers.
Keep your thumbs at the back of the blade,
the flat part of the blade,
and just use anything really, the wall,
the end of your bench,
whatever you have handy so that you could
push up against it and essentially
fold the blade in half.
Now don't blink because you might miss it.
I'll go in slow motion for you. Ready?
Like that.
That pretty much does it so just get a
garbage tie, a rubber band, piece of tape,
anything that'll hold this together for you.
Now that we've folded our blade,
let's unfold it and get it ready for installation.
I like to clean the manufacturer's grease
off of the blade using a rag soaked in mineral spirits.
Be sure to pull the rag in the same direction
as the teeth.
Once the mineral spirits flashes off,
I spray a dry film lubricant onto the entire blade,
and wipe off the excess using a clean rag.
With the teeth facing down,
I gently maneuver the blade into position
over both wheels.
You may need to lower the top wheel
all the way down before the blade
will slide on easily.
Now that the blade is installed,
I bring the tension up just enough
to hold the blade on to the tire
so that it doesn't walk off when we turn it.
We'll tighten it a little bit more later.
For now let's talk about the tracking.
The tracking is adjusted essentially
by tilting this wheel out or in
and causing the blade to walk in
one direction or the other.
The perfect setting is directly centered
so that it's not walking at all.
With the saw off and unplugged,
you want to rotate the wheel by hand manually
and make adjustments to our tracking.
Once the blade is tracking in the center of the tire,
and everything seems pretty secure,
I'm going to tighten up the tension
just a little bit more.
I want to get it to the point that it's
going to be safe to turn the machine on
and test the tracking as the machine
is going a little bit faster
so we know for sure that it's not going
to walk off the tire.
But we don't want to turn this on
until we know that there's enough tension in there
to securely hold the blade in place.
It's still a little bit loose,
but I think that's good enough for now.
So close the doors.
Get everything nice and secure,
everything off the table,
and we're going to get ready to turn this guy on
in short bursts just to see what happens,
make sure everything looks pretty good.
(saw starts up)
Looks pretty good.
^Let's talk a little bit about blade tension.
^This is one detail that really seems
to be a challenge for many woodworkers.
I think the most likely reason
is due to this not-so-helpful, little gauge up here.
These spring gauges mean well,
but they're rarely accurate
especially in the smaller range saws.
In fact, in most cases it's a good idea to tension
your blade to the next highest number on the gauge.
If you have a half-inch blade,
bring the tension up to about five-eighths.
That's pretty good for a rough estimate.
Other methods for determining the proper tension
are plucking the blade like a guitar string
and listening for a particular note.
Well, I'm a drummer so you know
that's not going to work.
The most accurate method would be to attach
a tension meter to the blade.
But tension meters cost hundreds of dollars
so that's really not feasible either.
So what do I usually do?
I measure the amount of deflection.
^With the guide set about six to eight inches
^off of the table,
I use my finger,
maybe not that finger you silly guys,
my index finger to push into the blade
^and look for the amount of deflection.
^I use a moderate amount of finger pressure.
So what's moderate?
To me moderate is the amount of pressure
it takes to poke my wife in the arm
and knock her off balance.
(dramatic music)
Once you have that,
push on the blade and see how much
of a deflection we see.
^You really don't want any more than a half inch,
^and no less than a quarter inch.
Somewhere in that range is usually good.
I'm just barely getting a quarter here.
That's pretty tight.
I think that's where I want it.
Remember, there are some blades on the market
that are designed to run at low tension.
One in particular that I use once in a while
is a Timberwolf blade.
They actually have their own method
for setting the tension,
and I recommend you follow their instructions.
Now let's turn our attention to the guides.
The idea behind the guides is pretty obvious,
to help to keep the blade straight and true
under even the most demanding
of cutting circumstances.
Usually there's a set of guides above the table,
and a set of guides below the table.
Each set consists of two side guides,
and a rear thrust bearing.
The real challenge here is to find a way
of guiding this blade
without producing excessive amounts
of friction and heat both of which
can shorten the life of the blade
and decrease the quality of the cut.
The most basic guides are actually
small metal blocks.
These usually come standard
with a number of saws and I highly recommend
upgrading if you have these.
The metal-on-metal contact is just bad news.
Two inexpensive options to upgrade to
would be either Cool Blocks which are made
from graphite impregnated phenolic,
or ceramic guide blocks.
Both of those will reduce heat and friction.
They'll increase the life of your blade
and they will improve the quality of your cut.
If you're lucky, your band saw came
with bearing guides,
and if it didn't you can always upgrade
to that type of guide system,
but to be honest I think your shop allowance
is better spent elsewhere.
15 bucks for Cool Blocks
is a good return on investment.
150 bucks for Carter bearings, not so much.
But either way, the setup process is the same.
Let's dial in the rear thrust bearing.
We want the bearing about a 64th of an inch
behind the blade.
This way the blade can only contact the bearing
if we're actually making a cut.
A nice trick is to use a business card
as a spacer.
Insert the card between the bearing
and the blade and bring the bearing forward
until the business card is held in place
without moving the blade.
As you can see I had to improvise on my saw.
I use a similar technique for the side bearings,
but instead of a business card
I use a sheet of paper.
Adjust one side at a time,
and remember we only apply enough pressure
to hold the paper in place,
but not so much that the blade moves.
One other detail to note,
make sure that your side guides are positioned
just behind the gullet of the blade's teeth.
Otherwise the sharp teeth can damage
the guides over time.
We can do another quick procedure
that will improve the quality of the cut.
The back of the blade will have a slight burr
on it from the production process.
This can actually create drag during the cut
which will make the cut less efficient.
Whenever you install a new blade
make sure you round over the back of the blade
using a silicon carbide stone.
You can get one just like this at Rockler.
The next thing we need to do is make sure
that the blade is perfectly perpendicular
to the table.
It's done easily enough using
a good engineer's square.
It helps if you have a little bit
of a light behind the blade
and you can actually see where the gaps are,
and you can adjust the table accordingly.
Just be sure to consult your owner's manual
to find out exactly how to adjust your table.
Not every saw is exactly the same.
New band saw owners usually have
a rude awakening when they line up their fence,
start cutting, and then they realize
the blade seems to want to walk,
or pull the piece away from the fence.
It doesn't take long before you realize
that every blade seems to cut
at a slightly different angle.
This property is actually known as the drift.
You need to adjust the fence for it
every time you change your blade.
Some people say that if your wheels
are perfectly coplanar and everything
is set just right,
the blade will cut perfectly straight.
I've yet to come across a blade
that doesn't require drift adjustment.
So let's get down to it.
I start by scribing a line about a quarter inch in
from the edge of a piece of scrap
that's been milled on all four sides.
I then cut the line freehand
until I'm about halfway through the board.
At this point, I hold the board securely
while the blade comes to a stop.
I then use a bevel gauge to copy the current angle.
This angle represents the drift angle.
This is the angle we're going to have to follow
if we want to cut a straight line using the fence.
Some saws allow you to adjust
the fence angle directly.
Mine requires me to lock down the fence
and make the adjustments using the rail.
To test our tune-up,
I'm going to slice a thin sheet of alder
from this jointed and planed four quarter board.
One other thing that I tested but forgot to film
was making sure that my fence
was square to the table.
This is critical for cutting veneer.
As you can see with some basic adjustments,
we can cut some pretty thin veneer.
With some extra fine tuning,
we can even cut thinner sheets.
One other adjustment that we didn't cover today
is truing the rubber tires.
This involves creating a little jig
that sands down the tires
as you spin the wheel manually.
Basically just knocks down the high points
and cuts down on blade vibration.
Another good addition which a lot of band saws
come with these days is a tire brush.
It just mounts to the inside of the unit,
and the brush sits along the rubber tire
and as it spins it actually cleans off
the dust and debris.
The last detail that I want to cover today
is blade choice.
The blade you choose depends on
the type of work that you plan on doing,
and even then there's a lot of opinions out there
about which blade is right for the job.
Just remember the basics.
^More teeth equals a smoother cut.
^Less teeth equals a more aggressive cut.
^If you plan on doing a lot of re-sawing,
you might want something that's
a pretty aggressive blade,
^something like a half inch hook or skip tooth blade
^with three teeth per inch.
If you plan on cutting veneer,
I usually use something that's
^probably around a half inch or three-quarter inch
^hook tooth blade with four or six teeth per inch.
For scrolling work and general curve cuts
^I recommend a quarter inch blade
^with at least six teeth per inch.
But remember these are just my recommendations
based on my experience.
Over time you'll develop your own preferences,
and they may be completely different than mine.
Thanks for checking out the podcast.
If you have any questions or comments,
^feel free to email me at TheWoodWhisperer@gmail.com.
^I just want to say thank you to everyone
for clicking on the links
and shopping at The Wood Whisperer Store.
We really do appreciate your support
of the show.
I also have a few quick announcements.
In case you haven't heard,
^we're now selling the Wood Whisperer
^video podcasts on DVD.
We're trying to squeeze as many episodes
as we can on each DVD so that you get
the most bang for your buck.
Click the link at the top of our home page
for more details.
One other quick announcement,
it's about a new podcast.
I'm sure most of you know Matt
from Matt's Basement Workshop.
Well, he and I have been discussing
the possibility of starting
a special new audio podcast.
^It's going to be called Wood Talk Online.
^The show is going to cover
all kinds of woodworking topics
including tips, techniques, emails,
and even stories from our own shops.
In other words, it's just two guys talking wood.
If you have any questions that you'd like
answered by Matt and myself,
^please email us at WoodTalkOnline@gmail.com.
Thanks, everybody.