"Leon" lcb11211@swbelldotnet wrote in message
...
On 10/30/2012 12:05 PM, wrote:
On Monday, October 29, 2012 5:27:42 PM UTC-7, Swingman wrote:
On 10/29/2012 6:59 PM, Larry Kraus wrote:

Swingman wrote:



Leon lcb11211@swbelldotnet wrote:

On 10/28/2012 7:33 AM, wrote:

Make a DIY bandsaw tension gauge:



http://www.youtube.com/watch?v=9iAkRLvLAvI



Apparently, I have been applying way too little tension on my
blades.

Now I have a much better idea of where I should be w/ tension.



(I was never a big fan of the pluck and listen for a tone
technique.)







Good information and findings but how about a tension warning
indicator

that lets you know when to retention during sawing operation. When
the

blade warms up from simply spinning it will stretch, more when
cutting,

and then less when not cutting.



While we all would like to be able to narrow this down to an exact

science temperature changes every thing.



On my saw the tension gauge is on the exterior in plain site while

cutting. Most saws require you to turn off the saw and open up the
wheel

cover to recheck tension. I find it quite common to have to
retention

considerably after only a few minutes of sawing and after a few
minutes

of cooling down the blade is over tensioned.



Something to think about.



Yep, making it more important to be properly tensioned to start with.



Figuring that industries relying on the bandsaw would be addressing
that as

a concern, this is an interesting read on the subject, which also
raises

the question, how do you put a "back-crown" on a bandsaw blade?



https://www.fornis.net/system/files/machining_LUS.pdf



Best I can translate the jargon, their concern was that the toothed

edge of the blade expanded from friction heat, effectively reducing

the tension on the front blade edge. To maintain uniform blade tension

at operating temperature, I think they are suggesting that the rear

edge should be longer than the front.



I may have some OCD tendencies, but such concerns too over the top to

be helpful in my shop.



No **** ...



You'd have to have a big honking blade to just "increase the tension to

the tooth edge" of the blade, or some such words.



That said, I do agree that the most heat would be generated at the tooth

edge, and the wider the blade, the more heat dissipation toward the back

would occur, with less loss of blade tension.



IOW, use the widest blade possible, consistent with the task, and it

shouldn't be a big factor on whether the cows made it home.



--

www.eWoodShop.com

Last update: 4/15/2010

KarlCaillouet@ (the obvious)

http://gplus.to/eWoodShop

If the blade tension spring is properly designed, it should compensate
for the blade length changing as the blade heats and cools.
Kerry


Can you name a brand that has a properly designed tension spring? Not the
case on my Laguna LT16HD.

And since tension is increased with the compression of the tension spring,
how would a properly designed spring maintain the proper tension as it
decompresses when the blade stretches?



Leon,
I'm not familiar with enough bandsaws to know if any have a tension spring
that does this well.
A long enough tension spring would change its length by a small enough %
that the force it exerts would be close to constant.
Kerry