Hazard !

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twice now I have had my band saw blade jump and grab the chunk of wood, It's one of the fastest things I've seen happen in a long time.

So whats the main cause ?

Blade stretching out ?
operator screwing up ? I've been very anneal about keeping a steady hand on the wood and tight to the bar and bed.
 
Can you describe a bit more what's happening here, I'm not quite sure what you mean by "jump" in this context? Sounds a bit nerve wracking!

The two guesses I have based on things I've done wrong are:

The blade is to coarse. If you don't have ~3 teeth in the wood at a time it can get a bit grabby and start pulling the wood around. The problem gets worse the thinner the wood you're cutting is.

You don't have adequate support under the cutting point. I've had this happen when cutting uneven pieces and the piece will pull down and forward kind of slamming it into the table. The best solution is of course setting it up so the workpiece is always fully supported, failing that you can get away with it a bit easier with a finer blade (see above) and feeding slower.
 
I dunno sounds like its grabbing pretty hard though. The only times I've really had a bade get wedged badly was with really bad reaction wood and I did have some of that pinch down on the blade hard enough to slow things down. The trick there was the opposite of the above and a coarser blade with more set to make a wider kerf to clear the back of the blade. I've only had that happen with pretty good sized chunks though (like 8-10" thick).

How thick of a piece were you cutting?

Would be interesting to see a picture of one trapped in place if you have it happen again.
 
6-8" W , 10-12"L i need to get a new blade tomorrorw.

Are you trying to rip cut a round piece - like trying to rip a log section - and having it twist?

Or are you trying to cross cut a log (or branch) section into slabs? and having it rotate?

Neither type of cut should be attempted unless you have the workpiece stabilized on some sort of sled.
 
Ok, yeah so that's what I meant by "no support under the cut"... Definitely a good way to get in a wreck in a hurry. If there is air under the piece where the blade is exiting the work at any time and the piece isn't solidly locking into a jig or a sled, stop and figure out a better way to do it.

You can see what happens in this video at about 1:00 in, he also has a somewhat reasonable sled setup. I'm not quite convinced that is cookie cutter version has adequate support for my liking but its better than nothing:

https://www.youtube.com/watch?v=Kb1QC-Zv2PI
 
I have had the blade grab wood before. Sometimes I find it is because I am using a really coarse blade (3 teeth per inch), and sometimes I need to use a finer blade. Also, I find that the blade has stretched from the heat and I need to tighten it a bit. A jig of some sort is still definitely the way to go. With a malfunction like that constantly occurring, I'd be more concerned about missing hands or fingers more than having to buy more blades. Every time I use my band saw I think it usually is the slowest process I ever do. Not scared of the danged thing, but I do have a nice respect for it.
 
For what your doing on your saw I'd go with a 3/8" hook tooth 3tpi blade.

I'm running something pretty similar on my 17" saw and it rocks for roughing green stuff.
 
We're 80 miles from anywhere and 100 miles from nowhere. There's a good junkyard, a decent farm store and a couple of mediocre grocery stores (except for the discount place with weirdly weird and good cheese). Other than that it's an hour plus drive to Portland OR, and honestly I don't reckon the pickings are as good there as you have it either (pickings are pretty good but..). The advantage though is that three cars seems like a lot of traffic on the way to work ;)
 
For what your doing on your saw I'd go with a 3/8" hook tooth 3tpi blade.

I'm running something pretty similar on my 17" saw and it rocks for roughing green stuff.

My go-to blade is a 1/2" 3tpi hook tooth. Pretty similar, just not as good at cutting curves.
 
My go-to blade is a 1/2" 3tpi hook tooth. Pretty similar, just not as good at cutting curves.

Yeah, a 1/2" is a smidge more stable for straight cuts, but with the smaller curves Dave's cutting I figured downsizing a smidge would let it go a bit smoother and the 3/8" is still sturdy enough to rip with whereas I think the 1/4" feels a bit flimsy for that.

Of course ideally you'd have two saws, one big heavy one with a 3/4" heavier blade for serious ripping and another saw with a 1/4" for curves ;). For bulk small work like that I've found compromising on a medium blade is more efficient than switching back and forth on one saw and not having two.... shrug.

That was the thought process anyway, for better or worse.
 
I will not be using it this afternoon. One of the problems Jarrod found is the lower tire is slipping off the wheel. So I ordered couple of new ones. Looks like turning some blanks instead.
 
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