My bandsaw has had a weird habit lately.

[Steve Knight]

been using my delta 14" saw for about 10 years. been using the same blades lenox bi metal blades forever too. the first time it happed I was removing a piece of wood I cut only part way. sometimes the wood binds a bit and pulls the blade. but it does not cause a problem. but now the blade will jump forward and be about 1/2 on and 1/2 off the wheel. at first I played around with the tracking to get it normal. but I found that if I just undo the tension and get the blade in the middle and tighten it it will move again the first time and stay the second usually. till something causes it to jump 1/2 off the wheel again. it tracks fine till that sudden jump. then it will stay there untilled I change the tracking or undo and redo the tension. the second time it happened it cut right through the blade guard sure startled me (G)

[Steven and Gail Peterson]

That is the main thing they warn of when you try to back out of a partial cut. Have you rounded the back of the blade? That might help. I have a cut blade guard too, from the back of the blade cutting in. Part of my education.

Steve

[George]

Tires could be your problem. If they're gummed flat or losing their crown, it's easier for the blade to run forward. Keep a couple of wedges at hand to open the kerf before you start backing out, BTW.

[Hax Planks]

Just a few guesses that you probably already thought of. Maybe some embedded saw dust on the tires or just worn tires. Maybe the tires are concave after years of use. Maybe there is a loose spot where the glue let go or maybe there is a crack in a tire. I would change the tires if it keeps happening.

[Steve Knight]

I glanced at them and they seemed ok. I don't get gum as I only cut tropicals. when the wood dues pull at the blade when I pull it out it is only slightly since I am cutting tropicals. but it even happens if a piece of wood jams in the throat plate. I will inspect my rubbers tomorrow (G)

[Sawblade]

It is not obvious from your post, but have you tried changing the blade? I am using the same saw and had a similar problem before finding an ever so slight kink in the bandsaw blade that caused it to jump on the wheel from time to time. I had virtually overhauled my machine before figuring it out, but it probably needed a good cleaning and alignment. After putting a new blade on, I was back in business.

Sawblade

[Sawblade]

It is not obvious from your post, but have you tried changing the blade? I am using the same saw and had a similar problem before finding an ever so slight kink in the bandsaw blade that caused it to jump on the wheel from time to time. I had virtually overhauled my machine before figuring it out, but it probably needed a good cleaning and alignment. After putting a new blade on, I was back in business.

Sawblade

[Prometheus]

Check the bearing on your idle wheel. We were having a problem with this on one of the big saws at work, and about a week later the whole bearing ripped itself to shreds. Made a lot of noise, but it didn't damage anything- but with a 14" shop saw, that may be a different story. It's definately worth checking out, anyhow. Aut inveniam viam aut faciam

[patrick mitchel]

Steve; Sounds like you did sumpin to anger the tool gods. Add the chisel and now the BS, what's next? I wouldn't ride that recumbent any longer, it might conspire to do you in. Reminds me of the twilight zone epp where all the appliances conspire against the critic. Regards Pat (stratus rider n sawdust maker)

[Steve Knight]

will do.

[Steve Knight]

two or three blades have done this. though it seems to be getting worse.

[Steve Knight]

you would think with all of the added gods I have made I would be immune?

[Fly-by-Night CC]

Hmmm. I have a 14" saw but don't know what an idle wheel might be...

BUT this brings another thought to mind - maybe one of your wheel bearings is sloppy or perhaps something has entered the bearing and intermittently gets pulled into the rotating action - causing the wheel to jump.

[Steve Knight]

ok I checked the bearings atleast in the top wheel. don't know why I did not check the bottom (G) but they seemed nice and smooth. the rubber looks good and still has the same crown it always has. nothing gets pulled in just sawdust.

[Prometheus]

The idle wheel is the one that spins freely when you do not have a blade installed. I never really bothered to check to see what Delta called it in the manual for my little benchtop one, that's just what HE&M calls them in the big ones. Sorry for any confusion on that point.

Aut inveniam viam aut faciam

[Fly-by-Night CC]

Ah, I was thinking along the lines of an idler pulley - to tension a drive belt or somethingalongthoselines.