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Rick Hubbard
06-08-2008, 12:21 PM
This morning I was happily re-sawing some 2X5 oak planks into ¾ inch boards. Eventually, after an hour or so, I realized my Grizzly 14” saw was making some peculiar noises. I stopped to investigate and discovered that the lower guide bearings had loosened, so I tightened them and re-tuned the saw. Afterwards, I was dismayed to discover that the saw blade would no longer cut straight (it seemed to push in in-feed end of the board off to the right of the blade and actually pulled the stock away from the fence). I re-tuned the saw a dozen times or so, adjusted the fence and still, no matter what I do, I encounter the same problem.

At this point, I suspect that what MAY have happened is that when the lower guide bearings worked loose they moved forward and pinched the set out of the blade. As luck would have it, this is my last blade so I really can’t compare the “feel” of the teeth to a known-good blade (and there is no place open today to buy another one).

My question is whether a blade with no set left in the teeth would cause this problem and if not, does anyone have ideas about what I might try next?
Thanks,
Rick

Wilbur Pan
06-08-2008, 1:20 PM
Perhaps your guide blocks may have altered the set, but or your bandsaw blade just got to a point where it has gotten a little dull from resawing your oak, and now you are seeing drift.

Luckily, you can compensate for this pretty easily. Have you ever tried resawing freehand on your bandsaw, or using a point fence? Or can you adjust your fence to account for the drift angle?

Curt Harms
06-08-2008, 2:26 PM
having the guides rub the teeth would likely do it. I've had 2 blades do exactly what You describe, one Timberwolf and one Supercut. My reaction when I had problems with the Timberwolf (first time) I thought something had come loose or failed with the saw. I checked wheel coplanarity, tension, tracking, no better. Put a different blade on and violá, it cut just like before. I couldn't discern any damage to the blade, but there was clearly something wacky with it. I suspect this is the reason to only use resaw blades for resawing and straight cutting. No curve cutting or any cutting that could cause problems with the tooth set. You could also do what Wilbur suggests and use a single point fence so you can compensate for drift. The supercut blade that started to drift still cuts fine but drifts. I prefer bandsaw blades that don't drift.

HTH

Curt

Rick Hubbard
06-08-2008, 3:45 PM
Luckily, you can compensate for this pretty easily. Have you ever tried resawing freehand on your bandsaw, or using a point fence? Or can you adjust your fence to account for the drift angle?

UH OH. Something is REALLY going on here. I tried resawing free hand on a piece of (short) stock as you suggested. The blade seemed to follow the upper line just fine (in fact I had defined it with a kerf on the TS). While the blade seemed to cut fine, when I finished sawing the piece, the bottom side of the cut had wandered toward the fence!

Whats with THIS?

Rick

Pete Bradley
06-08-2008, 5:41 PM
I think your band got eaten by the guides. Bands are cheap. Buy 3!

Check the guides too to see that they're not chewed up.

Pete

Curt Harms
06-08-2008, 8:04 PM
I think your band got eaten by the guides. Bands are cheap. Buy 3!

Check the guides too to see that they're not chewed up.

Pete

What Pete said!!! Dimes to donuts a new blade will fix all your ills. Both of my blades that got screwed up looked fine but they certainly were not fine.

Curt

Rick Hubbard
06-08-2008, 8:19 PM
Check the guides too to see that they're not chewed up.

Pete

It looks like this might not be good news. I noticed that one of the guide bearings no longer spins freely.

I wonder if these are off-the shelf kind of things or do I need to order replacements from Grizzly?

Rick

Jon McCoy
06-09-2008, 4:41 PM
I wonder if these are off-the shelf kind of things or do I need to order replacements from Grizzly?

I found a suitable replacement at the local Ace hardware store, when I needed the saw running again ASAP. You could also look up a bearings supply store and buy bearings that'll last longer than the cheaper ones from Grizzly and the hardware stores. If you're a belt-and-suspenders kinda guy, you can replace all six guide bearings while you've got it torn down. :)

-jon-

Wilbur Pan
06-09-2008, 8:27 PM
The blade seemed to follow the upper line just fine (in fact I had defined it with a kerf on the TS). While the blade seemed to cut fine, when I finished sawing the piece, the bottom side of the cut had wandered toward the fence!

Whats with THIS?

Again, could be a dull blade. I'd bail on this one and get a new sharp blade, and get a spare while you're at it. Life's too short to spend time on dull blades.

Pete Bradley
06-09-2008, 8:50 PM
The guide bearings will be something you can buy anywhere. Look for a number like 6XXX on the old ones to be sure, or you're pretty safe matching them up by eyeball at the hardware store (since it will only carry ultra-common sizes).

Don't bother with quality bearings for guides. They'll be trashed externally long before the internal quality matters.

Pete