: the issues I would check are: -are you using a wide enough blade? The wider
: the blade the better. The stock blade which comes with the saw was
: probably only about 1/4 of an inch. Try and get 1/2 inch or more.
: -is the blade tension tight enough?
: -are the blade guides in tight enough (ie minimal slack)? The blade guides
: which came with my Delta saw appeared to be plastic. The deteriorate
: pretty quickly. I got some aftermarket guides which are some type of
: composite. That really helped.

All the above are worth a look-see.

When ripping with the bandsaw you need to go to the widest blade your saw will handle ( per manufacturers recommendation ).
You need to get your guides properly adjusted as they keep the blade from drifting.
You need a sharp blade. You can tell if it's sharp by ( with the saw "off" ) running your fingers up the blade ( both sides ) and it should snag the skin as you go.
If the blade wants to go one way mostly, it's usually dull on one side. Get another blade.
If it's just flopping back and forth, right to left, then the guides are too loose. As Frank mentioned, some saws use plastic guides and they are somewhat useless. They will wear out on just one job like this. Try to locate metal guides that will substitute in their place.

If the guides are correctly adjusted the blade should NOT drift. It should cut straight and true.

As was mentioned, try the adjustments and grab a piece of scrap wood and give it a try.

Hope you can get this situation worked out as it's no fun trying to work with tools that aren't properly adjusted or sharpened. It's a Pain!!!

Rehd