Replies

1. 
   Andrew | May 11, 2002 06:02pm | #1

   Chris, as far as tension goes FWW had an article on how to make a simple tension gauge a little while ago, I'll have to look up the issue # though. I think the problem you have is that after the blade was welded it wasn't annealed properly leaving a very brittle weld that would snap in no time. I would take the blades back to the person who welded them and have them rewelded or replaced. most companies that I've seen guarantee their welds. hope this helps

2. 
   forestgirl | May 12, 2002 05:15am | #2

   You might want to try a different blade -- If it were me, I'd call Suffolk Machinery (Phone:800-234-7297) home of Timberwolf blades, and have a long talk with them.  They can give you all sorts of very good information, send you a blade, and be glad to answer questions later when you have them.

   Another good resource for help on older bandsaws is Iturra design.  They have a blade tension gage for $135 in their catalog.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

1. 
   LCHN | May 13, 2002 05:37am | #3

   Suffolk Machinery's website has a detailed page on how to adjust the tension on your blade, not quantitatively with a scale or something but by behavior/performance of the blade, which is ultimately what you need.

   Its rule "A" on this page.

   http://bandsaw.timberwolf-band-saw-blades.com/sixrules.html

   Edited 5/12/2002 11:46:21 PM ET by LCHN

3. 
   sschefer | May 13, 2002 08:29am | #4

   Chris, its the tires.. The blade is working in two directions at once. Thats not something bandsaw blades are supposed to do. Straight tension and you can usually crank them to whatever tension you like. In most cases, the blade will take far more tension than your saw is capable of producing. But.. if your tires are uneven or lumpy they will walk the blade in a horizontal manner and soon there after they will snap on you. In essence, the blade is oscillating.

   Steve - in Northern California

4. 
   gerry001 | May 13, 2002 03:06pm | #5

   Chris, I'd tend towards Andrew's thoughts on a brittle weld, but it that doesn't do it, some more detail might help. What blade size is this? Include tooth style, thickness, teeth-per-inch if you can. What are you trying to cut with this? Is it 3/4 inch, or 8-inches thick? Staight cuts or curves?

   On tensioning, Suffolk's web site focuses on their low-tension blades, but can be a starting point. If you follow that and reduce the tension until the blade wanders (do it slowly), then tighten up several turns further than they say, and check with a test cut.

   You only need enough tension to keep the blade on the wheel, and prevent any crown or bow at a moderate feed rate. What's moderate? If your cut's not vertical or you feel the wood jump as you feed, then slow down.

   You might also try Lonnie Bird's bandsaw book to help in checking out the machine. Another fellow mentioned a tire problem. While it's possible, without knowing the blade size and what you're cutting I don't know how close that would be. A wobbling wheel or other issues can do the same, e.g. cutting 4" fast with a 1/8 blade.

   If I had to make a guess, I'd take the simpliest one, and say you're over-tensioned and feeding too fast.

   Gerry

1. 
   tablesaw635 | May 13, 2002 05:03pm | #6

   Hi Gerry

   Thanks for your response- to provide some missing information, I'm using a 1/4" blade (6 tpi) to cut 1" hardwoods.  I try to be pretty conscious of not feeding too quickly, and don't feel like I'm shoving material in too fast, although I'll try slowing down more.  I'm not cutting uncomfortably small radii, just long, soft curves that don't seem to put too much "twist" on the blade as I go.

   I'll be putting a new blade on later today, and I'll take your advice on using a lower tension (using the Suffolk website as a starting point).  Thanks again!Chris Gleason

   Gleason Tableworks

   http://www.interestingfurniture.com

1. 
   gerry001 | May 13, 2002 07:43pm | #7

   Chris,

   One other thought came in: flex the blade by hand to about 1/2 the normal radius, and move the weld to the edge. See if there's any visual difference there. Not sure how sensitive this test would be, but if you can actually see a difference, that's probably bad.

   Gerry

2. 
   StanleyNiemiec | May 14, 2002 06:41am | #8

   I am not familiar with that machine center per se but you might wish to check to see if the wheels have any tilt.  Sometimes tilt will be added to a saw so that blade strain is greater of the front edge than on the back.  Sometimes tilt goes along with putting back in a blade (having the back side of the blade longer than the front side (so that the blade is a section of a cone rather than a section of a cylinder).   If the machine center is set up to run with tilt and back, the wrong style blade will have unequal strain;  if this strain is sufficiently dissimilar, you will break blades a lot. 

5. 
   PlaneWood | May 14, 2002 02:52pm | #9

   Interesting!  After recently changing the tires on my Craftsman bandsaw, I had my first blade break.  Actually not my first, but it's been so long that I can't remember the last time.  Over 10 years ago.  There has got to be a connection to the recent changing of the tires.  I did equalize the tension in the tires before running though???  The blade had been used quite a bit before changing the tires.   I never reduce the tension after usage.  The break was at the weld.

   PlaneWood by Mike_in_Katy
   PlaneWood