@Team_Woodshop just fyi, the 1" resaw blades for the big laguna bandsaw look like they’re completely spent.
edit with pics:
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Ahhh see hardened steel teeth ground flat lol!
Lol
Hardened teeth started hard.
Hardened teeth got too hot.
Hardened teeth got annealed.
Hardened teeth not so hard any more, are they.
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Yea now imagine the time and effort required to do that with pieces of wood! And the gross oversight needed to not notice, cause getting to temps where the steel would lose its temper would cause some smoke unless the woods wet and then it wouldn’t be heat it’s be just pure friction but Most Hardened steel things are already annealed without it they’d almost be glass, it keeps them hard but with a tiny flexibility
@Chris_Fazio I’m sure you are aware, but for others who may be lurking and don’t know: the ribbon part of the bandsaw blade is more ductile than the teeth so it can flex and not break, the teeth are locally hardened so they can retain their sharp edges. If you feed a lot of wood or dense wood through the teeth without letting the teeth cool down, the teeth will heat up. Likewise, if we let the resin and pitch from the wood accumulate on the teeth, that sticky substance will increase the friction and also heat up the teeth. If the teeth get too hot, the steel of the teeth becomes annealed and loses its hardness and edge-keeping characteristics. Obviously when the teeth become dull and we still try to force wood through them, they heat up even more and that’s when you get bandsaw blades that look like what we have, with teeth rounded down, with no cutting edge whatsoever.
tl;dr: keep your blades cool and clean and slow down your feed rate.
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So the back of the blades are kept iuntempered but they harden the teeth and then just as with any sharp knife the temper or anneal them because high carbon steel just tempered can shatter like glass, annealing or tempering keeps its hardness while giving it some flexibility if the teeth were just hardened theyd Snap and shatter off
Whenever referring to hardening steel annealing or tempering never carries negative connotation
Blades ordered.
I thought there was one more good blade on the wall? Please double check?
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the pictures above are of the one on the machine and on the wall
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Ah, thanks I missed that.
not to beat a dead horse, but I think you’re confusing annealing with tempering. Annealing is the process of heating up a carbon steel past the critical temp and when allowed to cool back down, it is no longer hard and won’t keep an edge. Quenched steel is brittle but then afterwards, the tempering process of heating up the steel to a temperature below the critical temperature and letting it cool will toughen it, make it less brittle and still allow it to keep a sharp edge. Carbon steel just quenched can shatter, but after tempered, can be both sharp and strong.
what’s happening to the blades is that the heat is getting above the critical point for that type of steel, and is becoming annealed, aka soft
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@Team_Blacksmithing is probably who you are thinking of @mblatz. If I’d guess I’d say they probably dont want it.
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Thanks but we have plenty of it laying around in the metal shop already.
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I apologize I thought they were somewhat synonymous, but after reading up on it, I was very wrong, I don’t think if I annealed a knife after hardening I’d be able to cut anything other than butter! So ignore all my previous comments lol
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No worries! This is a place of learning!
Ahhh I wish I read this yesterday! I went in late last night and used it for awhile. It seemed to be serviceable but towards the end of my project it started to wobble. I turned the machine off and the blade snapped while it was decelerating. I replaced the blade with the one on the wall after cleaning it.
I powered it back up and used it for a few minutes before it started to make intermittent dolphin noises. It didn’t sound normal so I turned it back off and switched saws.
I’m pretty new and not sure what the protocol is if I break a blade.
I’m excited to get a restock of blades. How do we purchase them if the kiosk is down?
Bandsaw blades are community resource - no need to donate unless you completely destroy a brand new one right after putting one on.
Otherwise I order new ones as the shop needs. Over time you may end up wanting to bring your own higher quality, sharper blades.
Good call turning it off when it hit “dolphin noise” mode. Sounds like you’ve got a good basic woodworking sense!
The big bandsaw? Are you ok? Cause blade snaps on those can be pretty scary, hopefully everything is ok! But when I was showing someone how to use the saw the other day, I told them when “a blade becomes unusable and you replace it, make it unusable aka bend it and put it in the trash that way it doesn’t mistakenly end up back on the wall and then someone goes to use it” then something like this happens where someone has no clue it’s a bad or bent blade and then goes to use it! But hopefully you’re unscathed and it’ll be back and going once the new blades get here
@Chris_Fazio Thanks for checking. I’m good. It was pretty underwhelming tbh but that’s probably because I had already killed the power.
Yea there a lot of little safety features that do alot to attempt to make it underwhelming but with steel under that much tension it has a lot of potential energy that can suddenly become a kinetic disaster but glad to hear
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