Bandsaw Saw down hill....

[David Nelson1]

Cutting tenons on the BS the other day and I noticed that the blade never touched the the scribe mark on the bottom. I didn't think much of it right then, but went back a bit later to have a look see and placed a square againts the back of the blade and the table. In 12 inchs its out by @ least 3/16 of an inch. Only thing I can come up with is that the trunnion bracket is bent or something got caught under it when I was assembling. I didn't see an adjustment of any kind so..... has anyone ever seen this before? BTW the BS is a brand new Jet 14DXPro. Thanks in advance.

[Ken Fitzgerald]

David,


Could it be that your table is tilted and isn't square to the blade?


If it is, could the tension on the blade be too low and allowing the blade to move into the area of least resistance within the wood?

[David Nelson1]

Nope, its off in the direction of travel not the way the table tilts and the blade is good n tite. The blade is square to the table as well as to the miter slot.

[Ken Fitzgerald]

David,

It sounds like one of 2 things to me then.

1. I'd check to see if your wheels are co-planar

2. See if the blade is riding on the front edge of one wheel and the back edge of the other wheel.

I can't see how any type of blade guide system would allow that to happen if the blade is on the wheels correctly and the guides are adjusted correctly.

[Thomas Knapp]

Nope, its off in the direction of travel not the way the table tilts and the blade is good n tite. The blade is square to the table as well as to the miter slot.

Are both of your thrust bearings set correctly? The bottom one could be pushing the blade too far forward. They should just lightly touch the back of the blade when the blade is free running. They can even be the thickness of a piece of paper away from the blade when no pressure is on the blade.

[Keith Westfall]

You may have to shim the trunnion mounts which should bring it to square. Sucks to have to do it on a new machine but...

[Thomas Knapp]

Cutting tenons on the BS the other day and I noticed that the blade never touched the the scribe mark on the bottom. I didn't think much of it right then, but went back a bit later to have a look see and placed a square againts the back of the blade and the table. In 12 inchs its out by @ least 3/16 of an inch. Only thing I can come up with is that the trunnion bracket is bent or something got caught under it when I was assembling. I didn't see an adjustment of any kind so..... has anyone ever seen this before? BTW the BS is a brand new Jet 14DXPro. Thanks in advance.

You mention the bandsaw is new. Are you new to seting up a bandsaw? Do you know the routine? back off all guides, install blade, Tension blade , check tracking on wheels, adjust guides to blade. Also what kind of blade are you trying to cut tenons with? A 1/4' blade can deflect more then a 1/2" blade. A blade with too many teeth for the stock thickness won't clear out the sawdust efficiently.
Do you feel much resistance when you are feeding the wood into the blade?
Of course you may already know these things and have prior bandsaw experience.

[Bill Wyko]

When you turn the saw on, do any of the guides make a sound? If bearings, are they spinning? The bearing behind the blade may be against it, pushing it towards you.

[David Nelson1]

Thanks for the suggestion guys I'll take a better look this evening

[David Nelson1]

Hi thomas, I followed the instruction to the T because this is my first band saw. the BS cuts great no wondering or excessive effort. I even resawed a few small pieces of pine with it. I think its a 1/4 width and does have quite few teeth. Its the OEM blade.

You mention the bandsaw is new. Are you new to seting up a bandsaw? Do you know the routine? back off all guides, install blade, Tension blade , check tracking on wheels, adjust guides to blade. Also what kind of blade are you trying to cut tenons with? A 1/4' blade can deflect more then a 1/2" blade. A blade with too many teeth for the stock thickness won't clear out the sawdust efficiently.
Do you feel much resistance when you are feeding the wood into the blade?
Of course you may already know these things and have prior bandsaw experience.

[David Nelson1]

No, Bill it doesn't seems that that is going on. I just went out and looked again keeping in mind the suggestion from everyone. I found the upper back guide to be farther away from the blade than I remember setting it up for. I also found that the blade is riding farther on the outside of the upper tire than it is on the lower. During setup I adjusted the blade to track in the middle ( I can't remember looking @ the lower tire for comparison to the upper during setup) I think I will blow the dust off everything this evening and go back through the setup adjustments again. I'll report back this evening.

When you turn the saw on, do any of the guides make a sound? If bearings, are they spinning? The bearing behind the blade may be against it, pushing it towards you.

[David Nelson1]

I went back over the settings and found that the lower roller guide was not square to the blade but that wont cause what I'm seeing. I removed the table, inspected the trunnion base plate, the mating surface for the trunnion mount, and the trunnion themselves. I then took a bubble level looking for a stable place to compare the machine base and the table. No luck with that at all.

The saw comes in 2 boxes. The base and the saw with the table unassembled. THe upper portion is bolted together from the factory. This is the area I think is the problem. Possible the riser area was mismachined or the trunnion area?? no way to tell with no level reference areas.

Sorry about the size of the photos cell phone was the only camera with batteries.
Any comments.

[Mike Cruz]

I would have to guess that your wheels aren't co-planer. If you have checked thatand the blade is riding in the middle of both wheels, then the problem must be in the table/trunion. I suppose either shimming or removing stock from the front trunion would help. By trunion, I mean the two pieces that allow the table to move. I've seen them called trunions on one of my band saws and I think they are called something else on the other.

[David Nelson1]

"I would have to guess that your wheels aren't co-planer."

The blade is riding in the middle and moves evenly on the top wheel as well as the bottom. How would you suggest checking the wheels for co-planer.

[Mike Cruz]

I will address co-planer in a moment...

What do you mean the blade moves evenly on the top wheel as on the bottom? Do you mean to say that while running it moves back and forth? Or do you mean while adjusting. If the latter, good. If the former, bad.

As for checking for co-planer, with the front cover/s off (and usually the table gets in the way, too, so you might want to take it off), take a straight edge (you will probably need at least a 4 footer, if not 5) and place it so that it spans the top of the top wheel and the bottom of the bottom wheel. The straight edge should also touch the bottom of the top wheel and the top of the bottom wheel. Make sense? In other words, the two wheels should be running directly in line with one another. Neither should be behind or in front of the other, nor should either be tilted/leaning backwards or frontwards. Get the picture?

It sounds to me like your upper wheel is forward of your bottom wheel. With the blade running in the middle of both wheels, that would draw the blade forward at the top, like in your picture (if I remember it correctly).

Any more questions, feel free to ask, even if I can't answer them...like how to fix non-co-planer-icity.