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woody dixon
09-17-2020, 9:02 PM
I just had a curious problem when I was resawing about a 5 inch wide board on my 14 inch old jet bandsaw. After a couple of inches the blade just snapped. After I removed it I looked at the top wheel and it would not move by hand, it was jammed against the top of the housing. I removed all tension from the blade and it would rotate but as soon as I put minimal tension on the spring, it would bind against the top. I removed the wheel and bent the top with pliers as much as I could and still shut the door and the same result. The bracket behind the wheel seems loose even after I tighten it back up but I dont know if this is normal or not. The screw in back which moves in and out to adjust the plane of the wheel just pushes against the bracket and doesnt engage any threads, but I dont know if this is what it is supposed to do either. Anybody got a clue as to what I need to do? I cant use the saw at all like this.


Woody Dixon

Bruce King
09-17-2020, 9:16 PM
Either the top wheel axle broke or something with the tensioner. With no tension wiggle on the wheel and see if it feels broken.

John K Jordan
09-17-2020, 10:29 PM
I just had a curious problem when I was resawing about a 5 inch wide board on my 14 inch old jet bandsaw. After a couple of inches the blade just snapped. After I removed it I looked at the top wheel and it would not move by hand, it was jammed against the top of the housing. I removed all tension from the blade and it would rotate but as soon as I put minimal tension on the spring, it would bind against the top. I removed the wheel and bent the top with pliers as much as I could and still shut the door and the same result. The bracket behind the wheel seems loose even after I tighten it back up but I dont know if this is normal or not. The screw in back which moves in and out to adjust the plane of the wheel just pushes against the bracket and doesnt engage any threads, but I dont know if this is what it is supposed to do either. Anybody got a clue as to what I need to do? I cant use the saw at all like this.


Woody Dixon

There is a tension bracket on the older 14" Jet and Delta bandsaws that can bend, usually from applying a lot of tension with blades too wide for the saw. Long ago I bent the one on my Delta by trying to properly tension and resaw 3/4" blades. If I'm remembering correctly when the bracket bends the wheel tilts further and further until the back of the wheel touches the back of the housing. Iturra Design sells replacement brackets that are much stronger than the factory bracket. I replaced the bracket and installed their stronger spring as well.

But if you mean the top rim of the wheel touches the top inside of the upper housing, I don't know. I think the tensioning bracket needs to be tight when the blade is tensioned. First thing I'd do is disassemble the upper part of the saw and examine the parts.

JKJ

woody dixon
09-17-2020, 10:30 PM
i disassembled the top and removed the sliding bracket assembly. The axle seemed fine but the hinge flops around and the screw behind it doesnt thread in to it. It looks like there might be part of the screw broken off in a threaded hole but the break is very clean. I watched some videos and the wheel with no tension was very close to the top of the cover and rubbed almost immediately when i applied tension. The sliding bracket is not cracked. I believe you have to buy the whole assembly but dont want to that is that is not the problem. Is the adjustment screw supposed to thread into the hinge? If so, could this be why the wheel feels so loose and it is too high when not tensioned? What else do I need to look at if this is not the problem? Thanks

Woody Dixon

woody dixon
09-17-2020, 10:36 PM
There is a tension bracket on the older 14" Jet and Delta bandsaws that can bend, usually from applying a lot of tension with blades too wide for the saw. Long ago I bent the one on my Delta by trying to properly tension and resaw 3/4" blades. If I'm remembering correctly when the bracket bends the wheel tilts further and further until the back of the wheel touches the back of the housing. Iturra Design sells replacement brackets that are much stronger than the factory bracket. I replaced the bracket and installed their stronger spring as well.

But if you mean the top rim of the wheel touches the top inside of the upper housing, I don't know. I think the tensioning bracket needs to be tight when the blade is tensioned. First thing I'd do is disassemble the upper part of the saw and examine the parts.

JKJ
Yes it is the top rim which is touching the top of the cover. The hinge is in the bracket is not tight. Is the adjustment screw supposed to thread into it? Mine looks sheared off perhaps but is awfully clean. That is the only thing that looks out of place after I took it out of the cover.

Woody Dixon

Keith Westfall
09-17-2020, 10:49 PM
Need pictures!!!

woody dixon
09-18-2020, 12:27 AM
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Need pictures!!!

here are pictures of the hinge not attached to the tracking screw. Is this the problem?

Doug Garson
09-18-2020, 1:02 AM
Assuming the 14" Jet is similar design to the 14" Rockwell/Delta I'm pretty sure the bolt you are referring to pushes the hinge to tilt the wheel and is not threaded into the hinge. That said not sure why the top of your wheel is rubbing on the housing unless you installed a blade that is too long in which case in order to tension it you would push it up too high. You say you broke a blade so I assume you installed a new blade, are you sure it is the correct length?

woody dixon
09-18-2020, 1:30 AM
Assuming the 14" Jet is similar design to the 14" Rockwell/Delta I'm pretty sure the bolt you are referring to pushes the hinge to tilt the wheel and is not threaded into the hinge. That said not sure why the top of your wheel is rubbing on the housing unless you installed a blade that is too long in which case in order to tension it you would push it up too high. You say you broke a blade so I assume you installed a new blade, are you sure it is the correct length?


The blade has been on the saw for several years cutting fine.

Doug Garson
09-18-2020, 1:47 AM
The blade has been on the saw for several years cutting fine.
I'm confused, your OP said the blade snapped so I assumed the blade broke. If not the blade, what snapped?

Doug Garson
09-18-2020, 1:58 AM
Maybe post pictures of the whole saw. Looking at the pics you posted I think your Jet is similar to the 14" Rockwell/Delta design.

woody dixon
09-18-2020, 8:00 AM
I'm confused, your OP said the blade snapped so I assumed the blade broke. If not the blade, what snapped?
Maybe that is normal without a blade but the tracking screw looks like it should thread into the hinge in the picture making it more stable. The top wheel is too high and seems to flop around.

David L Morse
09-18-2020, 8:16 AM
The tracking screw does not thread into the hinge, it only presses against it. Did you release the tension after the blade broke? If not, then the wheel will hit the top of the blade cover without a blade compressing the tension spring.

woody dixon
09-18-2020, 8:23 AM
The tracking screw does not thread into the hinge, it only presses against it. Did you release the tension after the blade broke? If not, then the wheel will hit the top of the blade cover without a blade compressing the tension spring.

Yes but then I was trying to figure out why the blade broke and when I put tension back on the wheel hit the top cover and wouldn't turn anymore. So you're saying this is normal without a blade on the wheel? This would mean I have no problem and just need to replace the blade.

Dick Mahany
09-18-2020, 8:55 AM
Your description sounds much like what happened to me on my Delta 14" band saw. I broke a 3/4" resaw blade after trying to tension it for resawing. The blade worked well for awhile, but failed from stress crack fatigue. The top of the wheel was very close to the sheet metal housing and trying to tension the replacement blade only made it worse.

The problem turned out to be as JKJ described above. I had bent the bracket that holds the wheel axle and it is a known weak spot on these 14" saws. It wasn't very obvious to me at first look, but when I looked closely, I could see that the axle wasn't square to the bracket.

A new heavy duty aftermarket part from Iturra Designs (10405 Improved Tracking Arm) solved the problem. My upper wheel now has plenty of clearance at the top and the tracking adjustment and tensioning all work like new and no other parts were replaced. The Iturra axle mount is machined from a solid billet and has a shim pack that allows lateral adjustment if needed to maintain that the blade guides stay aligned on the blade through the height range of travel.

I'm not sure if that part fits the Jet, but a call to Louis Iturra would be helpful as he is very knowledgeable and helpful.

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David L Morse
09-18-2020, 9:12 AM
Yes but then I was trying to figure out why the blade broke and when I put tension back on the wheel hit the top cover and wouldn't turn anymore. So you're saying this is normal without a blade on the wheel? This would mean I have no problem and just need to replace the blade.

Yes. Release tension and try the new blade.

woody dixon
09-18-2020, 9:35 AM
Yes. Release tension and try the new blade.

Ok. One thing I forgot to mention was that when I first started resawing I noticed the cut was not straight and that the blade was no longer perpendicular to the table. I adjusted the table, started the cut again and the blade broke. Don't know if this is significant or not. Thanks.

David L Morse
09-18-2020, 10:16 AM
Ok. One thing I forgot to mention was that when I first started resawing I noticed the cut was not straight and that the blade was no longer perpendicular to the table. I adjusted the table, started the cut again and the blade broke. Don't know if this is significant or not. Thanks.

Well, yes, that could be significant. That's a lot different from just a broken blade. Reread Dick's and John's posts and inspect carefully. Pay close attention when you put the new blade on.

Lee Schierer
09-19-2020, 12:43 PM
Are you sure your new blade is the correct length? If the blade is too long the upper wheel can hit the shroud when you tilt the upper wheel. The tilt adjustment on the upper wheel is supposed to be for adjusting tracking only.

woody dixon
09-22-2020, 10:01 PM
Finally got my saw up and running. I got new upper wheel bearings, spring and carter tension rod from Iturra Design. Seems to be working fine except the upper guide block assembly is skewed to one side, i.e., the blade cannot be centered between my cool blocks. There doesn't seem to be any adjustment for this. I almost got the tracking arm Dick mentioned above but decided to wait and see if this worked. Would the shim pack he mentions above make that lateral adjustment?

Doug Garson
09-22-2020, 10:46 PM
Ok. One thing I forgot to mention was that when I first started resawing I noticed the cut was not straight and that the blade was no longer perpendicular to the table. I adjusted the table, started the cut again and the blade broke. Don't know if this is significant or not. Thanks.
It its possible that after you adjusted the table and started the cut again that the blade started to follow the original saw kerf thus putting extra strain on the blade.
When you say you cannot center the blade between the cool blocks, do you mean front to back or side to side? Maybe post a few pictures. I assume the Jet is similar to the 14" Delta so you should be able make that adjustment, a few pictures might help us understand why you can't.

woody dixon
09-22-2020, 10:51 PM
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Here is a picture of what I was describing showing the huge gap. Don't know why the picture rotated it is upright on my pc.

Edit: rotated photo, JKJ

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Dan Hahr
09-22-2020, 11:07 PM
Something is jacked up big time. Can’t help but think that it would be easy to see looking at it in person. Maybe walks away from it for a few days and then come back and give it a complete once over from the ground up.

Dan

Doug Garson
09-22-2020, 11:14 PM
Looks like the blade is centered in the table opening ok, if you put the insert in you should be able to confirm this. Is the post holding the blade guard and guides vertical? Did it get knocked out of plumb somehow? Maybe loosen it and retighten the knob on top?
Check to make sure the blade isn't hung up below the table, is it centered between the Cooblocks below the table?

John K Jordan
09-23-2020, 1:23 PM
Something is jacked up big time. Can’t help but think that it would be easy to see looking at it in person. Maybe walks away from it for a few days and then come back and give it a complete once over from the ground up.

Dan

Maybe get someone else with bandsaw experience to take a look at it.

JKJ

woody dixon
09-23-2020, 8:45 PM
Finally success. I must have loosened the bolt on the guide rod which allowed the whole upper guide assembly to rotate to the side. I just rotated it back and it is now centered. My bad. One good thing is I have a much better understanding of how the parts of the saw fit together and function. Thanks everyone for your help and suggestions.

Woody Dixon

Doug Garson
09-23-2020, 10:03 PM
Glad you got it fixed, now we can look forward to seeing what you make with it. :)