Bandsaw Setup Problem - Please Help!

[Hans Braul]

I am trying to get my new/old bandsaw set up. I have set the guides and wheel tension as instructions direct but when I turn on the saw the blade comes off the lower wheel. I think it must have to do with the adjustment mechanism for the upper wheel. This is the view from the back of the mechanism.
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Here is the view from the top
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The tension is adjusted by rotating the vertical screw, thereby moving the mechanism up and down inside keyways cut in the casting (excuse me if this is obvious to you, but I am just figuring this out). There is quite a bit of slop in this keyway. You can see the gap in the top view. Is this normal?

Also, there is a spring that is visible from the back but the vertical screw does not compress the spring and it serves no apparent purpose. Can anyone help me solve this? I would assume the spring should compress and the amount of compression should be visible in the slot which is marked 1/4, 1/2 and 3/4.

Any ideas would be welcome.

Hans

[Jim Chilenski]

Hans,

The tension screw should have a nut and a couple of washers on the bottom of the spring that you see through the slot in the casting. As you tighten the screw the tension on the blade will cause the spring to compress and you should see the washer appear. Continue increasing the tension until the washer is in line with the mark on the scale for the size of blade you are using.

When the blade is properly tensioned, you should only be able to deflect the blade by pressing on it's flat side by 1/4". This should be done with the upper blade guides raised all the way to the top of their travel.

Also, WITH THE POWER CORD UNPLUGGED, spin the wheels by hand to make certain that the blade is tracking in the center of the upper wheel. Tracking is adjusted by cranking in or out the horizontal adjustment screw.

Jim

[Pete Bradley]

Ordinarily, I would say that this is a problem with the tracking adjustment (the horizontal knob). However, you mention that the spring doesn't compress. There should be a square nut and a washer under the spring. As you tighten the tension knob (the vertical one), the nut should push up on the spring, raising the top wheel carrier. The play in the carrier is not a big deal. With the blade properly tensioned and the guides backed off all the way, you should be able to tighten or loosen the tracking knob until the band runs true when the wheels are spun by hand. Never turn the tracking knob while the machine is running!

You will also need a better understanding of how the machine works. This looks to be a Delta 14" or clone (by the way, where are the guards?). There are manuals avaialble on www.owwm.com (http://www.owwm.com) that might help. Duginske's band saw book would also be a good choice.

Where did you get this machine? Has it been apart? If so, more adjustments may be required. Owwm will also have articles on band saw tuneup. However, the object at first is to keep adjustments to a minimum.

Pete

[Hans Braul]

Thanks guys. I just figured out that the adjustment mechanism is a red herring. The reason the blade is coming off is because the rubber tire on the bottom wheel is a bit too big and buckles when the saw is turned on. That's why there is no sign of problem when I turn the wheel by hand. It is a different type of rubber from the top, so it looks like it's been replaced. Thanks for your help.

Hans

[Don Henthorn Smithville, TX]

Try going to Suffolk Machinery on line and looking their replacements for your band saw. Good company and good products. They will help you decide what you need.