Hi. So, this machine here is my homemade bandsaw
number 3.
One of my goals, when I built this bandsaw, was to
do a whole bunch of experiments in terms of bandsaw design.
So, in this video I'll go through
and I'll show you what I learned
and what works and what doesn't work.
So, on my previous bandsaw I built a
frame that holds the upper wheel mount.
And the frame slides up and down. And then
inside that frame the upper wheel mount tilts.
For this new bandsaw there's only one block.
And it moves up and down. And it tilts.
So, it's ported inside the frame here.
It slides in the slot. And, then
this holds it from tilting forward.
And this knob allows it to tilt.
It only needs to be able to tilt a little wee bit.
Because you really don't need to
tilt that top wheel mount very much.
Mostly just to compensate for inaccuracies in the build.
Partially because of the one piece
wheel mount, I can get the upper shaft
a lot closer to the frame.
Which means I could move that frame
member up a little bit further.
Which gives me more resaw capacity right here.
So, on this saw I can move the upper blade guide.
Like this. The distance that is 24 centimeters
or over 9 and 1/2 inches above the table.
But, I can go further than that.
Because I can take this block off.
And re-position it higher.
And now that blade guide
goes up as far as
30 centimeters or 11 and 3/4 of an inch.
So, almost 12 inches.
And, that's quite a lot because this is just a 14 inch bandsaw.
And it uses a regular 93 and a half inch blade.
Which is the same that your typical
14 inch bandsaw would use.
So that one piece top wheel mount has really worked out.
The only problems I've had is the varnish can get sticky.
So, it helps to put a little bit of plastic in between.
Or wax it, or something so that the
varnish doesn't stiick to itself.
Now, the next experiment I did is I made the wheels out of MDF.
Because people often ask if it's ok to use MDF for the wheels.
And, as much as I don't like MDF, I thought I
should try it out just to see how it works.
And it's worked out fairly well. The
wheels are very dusty when you turn them.
But, to produce a fairly consistent surface
I've varnished them with an oil based varnish,
just to make sure I don't get any water in there.
And, so far so good.
The stress of the blade pushing down
like that is actually not as bad
as having a shelf full of books. Because
the straight down pressure is not as bad
as a bending force. I did make the
flanges out of Birch plywood because
those need to be really strong. Because that bearing
has to fit in there really, really tightly.
So, if you do make the wheels out of MDF, it does work.
But, make the flanges out of Birch plywood.
As with my other bandsaw I used
inner tube for the bandsaw tires.
And, I knew that would work. So, that
part wasn't really and experiment.
The next experiment was for a shaft, to
actually use a piece of plumbing pipe.
So, here's a piece of plumbing pipe,
which you can get at any hardware store.
And, this is a piece of shaft.
Now, the plumbing pipes worked out ok. But, it's necessary to
shim them so there isn't very much play.
That was ok for the top wheel.
For the bottom wheel
that was more of a problem. Because
I also have this flat belt
which needs a lot of tension pushing off to the side.
So, on here I had to be really careful with the shimming.
Because of the large side load from that belt.
So, my conclusion is
you can use plumbing pipe for the
shafting. It does bend before it breaks.
And it's strong enough for a bandsaw.
But, if you know now where to get shafting material
it makes it much easier to build the bandsaw.
Now, here's the part of the bandsaw
that gave me the most trouble.
I re-used an old pool pump motor.
And it's a 3500 RPM motor.
And, because I needed a relatively small pulley on it
to get the speed I wanted.
I thought an experiment with a flat belt pulley
to avoid the inefficiencies of a V-belt.
But, this flat belt thing has given me a lot of trouble.
Just getting it to track right. And getting
enough tension so it doesn't slip.
So, I really don't recommend that.
On my old bandsaw, I just used an old 1750 RPM furnace motor.
And, that motor has really worked
out well. It's very quiet.
And I just have a V-belt on there. The pulley
is much larger because the motor is slower.
And, the 1750 RPM motor runs much quieter than this one does.
So, to give you an idea of the different noise levels
Here's bandsaw 2 running with the old furnace motor.
And, here's bandsaw 3
running with the pool pump motor.
So, I wanted to avoid the inefficiency of a
V-belt when going around a tight radius.
And, for this belt, you can really feel the
resistance for it unbending and bending.
But, the flat belt was such a bother to get it to work
ok. I should have just experimented
with different types of V-belts.
So, for example, this V-belt
with only the cloth around the edges
and having the teeth in here.
It, actually is much more elastic. So,
that could go around a small pulley
without losing too much energy.
Or, I could have just experimented
with using a thinner type of belt.
So, this belt for instance, is out of my drill press.
And it's a 3/8th inch belt instead of a 1/2 inch belt.
So really, the flat belt is not worth it.
And in the plans, I'll change it to a V -belt.
The reason I only made this saw a 14 inch
saw instead of a 16 or and 18 inch saw
is I want it to be relatively portable.
And at 82 pounds It only weighs
a little bit more than one of
those portable thickness planers.
So, it's still relatively transportable by hand.
So, with this bandsaw being a relatively small machine
I can use it as a bench-top saw.
And it's still at a reasonable working height.
Now, a final experiment with this bandsaw is
I used hinges for tilting the table instead of trunnions.
So, that simplifies construction quite a lot.
But, unfortunately it means
if you want to have an insert with a
hole that's big enough or all angles
that hole has to be quite large.
Of course, I can always have different inserts
for different blade angles.
But, if I put different inserts in there,
there's a risk that I might forget that
I put the 90 degree insert in there and then tilt the table.
And, at that point, I'd bend the blade.
Another design change is that the table
support actually comes around the right side
instead of the left side.
That means you can't get the blade out this way.
Which means the blade has to be removed coming out to the left.
But that turns out to be not a problem at all.
So, the table, on this bandsaw is
actually relatively easy to remove.
So, now with the table removed.
And the upper blade guide all the way up.
The distance between the blade guides here
is actually 35 centimeters or 14 inches.
And the reason I want so much
distance between the blade guides
is the reason I actually built this saw
is to try to use it as a sawmill.
So, I'm still experimenting with
using this bandsaw as a sawmill.
And I'll have more about that in next week's video.