Thread: Understanding bandsaw drift

I don't cut circles and any curved cutting I do is usually mirrored, so I haven't encountered the phenomenon you speak of.

I would have thought that as long as a blade of suitable width is used for the curvature being cut there shouldn't be any perceivable wear bias.

http://www.ccwwa.org/NEWSITE/plans/BandsawTuneup1.pdf

Michael Fortune's article Just "save as" and it will download as a pdf

After reading yesterday about the bandsaw drift, i went,had a go and stone me it worked, so I was well pleased.
But i would like to ask is it just me or do you find the same, that when you go to plan the piece you want to cut, it doesn't seem to work and then you go out an hour later and just do it and it seems to work!! Do you think you can try too hard sometimes?

Cheers....

Originally Posted by JillB

Thanks everyone. Being used to a table saw, and never having used a bandsaw, I didn't understand that the bandsaw blade may pull to the left or right if the teeth are not set or cutting equally

If the teeth are dull on one side and sharp on the other then it would seem reasonable to think that the sharp teeth cut the wood (as normal) and the blunt teeth have resistance to cutting the wood.... so the effect is that the saw blade takes the path of least resistance and heads towards the sharp side and away from the blunt.
If we now assume the right side teeth are blunt and the left are sharp the effect is that the board will pull away from the fence as a cut is made, the cut piece starts at the set width as set by the fence scale and ends up narrow, for sharp right and dull left the opposite is we get thicker at the end of the cut as the blade is forced away from the fence by the widening piece.
This is blade drift and the fence is then set to the angle of the cut being made by the blade due to its current amount of bluntness, and as blade sharpness can change so can the drift angle and needs to be reset
That's my take on it anyways....


Pete

Originally Posted by bluntlarry

But i would like to ask is it just me or do you find the same, that when you go to plan the piece you want to cut, it doesn't seem to work and then you go out an hour later and just do it and it seems to work!! Do you think you can try too hard sometimes?

Cheers....

I don't think it's trying too hard.

I call it "outsmarting the gremlins" by sneaking back into the shed to get the job done while they're still out celebrating messing with your head earlier...