Replies

1. 
   RSRose | Nov 29, 2002 09:32am | #1

   It's a shock absorber.

   R

2. 
   blacksmith5 | Nov 30, 2002 02:15am | #2

   As well as a shock absorber it helps keep the rifht tension on the blade. If the blade isn't tight enough, in thick wood it will start doing a barrel cut. That will cause the blade to sieze, & stop the machine. You'll need a chisel to get the blade out of the wood!

   Richard

1. 
   UncleDunc | Nov 30, 2002 05:01am | #3

   Rich,

   That makes sense, but what shocks happen to a wood cutting bandsaw that don't happen to a metal cutting bandsaw?

   Richard,

   Why would the tension go down, that you would need a spring to guard against it? Is it because frictional heating makes the blade expand?

1. 
   nicobie | Nov 30, 2002 06:50am | #4

   Knots...

   Metal is the same all the way thru. Wood was alive at one time, some say it's never dead.The proof is in the puddin'

1. 
   RSRose | Nov 30, 2002 10:17am | #5

   And the wood saw is running at a higher blade speed. Bumps and grinds.

   R

2. 
   DennisS | Dec 01, 2002 04:58am | #6

   I don't own a metal cutting band saw, other than my little PortaBand portable jobbie - but my guess is, one doesn't put as wide a variety of saw blade widths on a metal cutting saw as one does a wood cutter. Thus if you consider the difference in cross sectional area between, say, an 1/8" wood blade and a 3/4" one, the same amount of tension that's required to 'stretch' out the larger one would come close to pulling the small one apart!(?). And the wide diversity of tooth designs for cutting wood vs cutting metal.

   The little PortaBand I mentioned above has nothing more than a lever that cams the idler wheel out to tension the blade. As far as I know there's little or perhaps no adjustment other than "off" or "on".

   As for the shock absorbing thing - I tried to gain entry in the Darwin awards book once by cutting a piece of large round stock without taking due precaution to make sure the piece was secure in a sliding fixture of one kind or the other. If anyone tries to tell you you can't get a "kick-back" from a band saw, send them over. Fortunately a band saw only kicks 'back' down onto the table but it can put a pretty gnarly crook in a blade even with the spring to absorb the shock.

   It can also make it worthwhile to change underware.

   ...........

   Dennis in Bellevue WA

   [email protected]