So. You've decided that your wood shop needs a band saw. Its use in resawing, scroll work and joinery are arguably unparalleled, so congratulations on your decision! Your duty to yourself as a consumer is education. This guide seeks to give you all the important information you need so that you can make the band saw decision that's right for you.
1) The All Important Application Analysis
First of all you need to have a clear understanding for yourself of how you'll be using your band saw.
Will you be doing lots of resawing? You need higher horsepower and a wider blade width capacity among other things.
How about scroll work? Horsepower doesn't matter quite as much here (unless you're working with thick stock) as allowance for a narrower blade.
Will you be using your band saw five times a week or five times an hour? This will give you an idea of how much you need to spend on the motor and whether you need a bench top or floor model.
Once you've answered the application questions for yourself you can begin to dig a little deeper into other aspects of a band saw.
2) Bench Top vs. Floor Model
As a very general rule, bench top models belong in non-professional wood shops.
Power hobbyists - those woodworkers who spend every waking minute in the wood shop - will point to the floor model band saw in their shop and disagree heartily.
Your bench top band saws are made to literally sit on your bench top or to be bolted onto a stand. They are compact and portable and ideal for light scroll cutting.
Floor models are more stable and more powerful and ideal for heavy rip sawing and decorative work on thick stock wood. Their higher horsepower typically keeps the blade from getting stuck and burning the wood you're cutting.
3) Throat Capacity
Another reason it's important that you know your desired application is throat capacity - that's the distance between the blade and the frame and it determines the maximum width of the saw's ability to cut.
The greater the throat capacity the wider your cuts and larger pieces for scrolling.
4) Blade Width
It's typical that band saws accept the narrower 1/8" blades for creating scroll work. If resawing is important to you then you've got to make sure you're getting a saw that accepts wider blades, as they flex less and enable more accurate, faster cuts through thicker stock.
If you're buying your band saw to make scroll cuts only then the acceptance of a wider blade should not be a consideration... then again in a few months you might be looking for new ways to resaw your lumber. Again, that's why the initial Application Analysis is so important.
A note on blades: TPI stands for "teeth per inch." A higher teeth per inch ratio means that blades will cut more slowly, but more cleanly. That's right - making them ideal for scroll work. A lower TPI means that blades will cut more quickly but leave more of a mark, suiting them for ripping.
5) The Possibility for Expansion through Accessories
There are a number of potential accessories for every band saw. Some more than others though. When you know your applications you'll have a better idea of which accessories you're going to need and which you don't need to allow for in your model of choice.
That said, it's a good idea to err on the side of MORE possible accessories than fewer.
Some accessories include circle cutting attachments for cutting perfect circles, tilting tables for beveled cuts, miter gauges, rip fences and even height extenders for cutting thicker wood.
6) Band Saw vs. a Jig Saw
The main functional difference between the two types of saws are that the band saws have blades that cut in one continuous loop, while jig saws go up and down.
It's generally held that the band saw is the superior saw due to the vibration of the up and down motion of the jig saw. Since the band saw blade only pulls in one direction there's no chance of upward thrust on the piece that could throw the cut out of true.
That said, the ability to change blades and even the extreme narrowness of some jig saw blades makes this question moot for certain types of highly delicate work.
7) Wrapping it up...
As with any woodworking tool purchase you're more likely to make a sound decision if you know exactly how you'll be using it ahead of time. Having a good idea of how your projects for the next several months will help ensure that you're getting the right tool for the job.