Broken band saw blade

[lilgodwin]

Had a 3/8" blade cutting through 2 pieces of mahogany for a total thickness of about 1.5". The tension was about 1-1.5 full turns past the 1/8" mark as I've seen countless times many suggesting to keep a slightly tighter blade tension than suggested by the Shopsmith Bandsaw guide. I was performing a really straight cut at the time. The guide was placed approx 1/4" above the stock. It got a little tough to move the wood forward for a second, and it broke. Loud pop, quite startling.

I'm sure there's always something I can do to be safer. But is a broken bandsaw blade something that's expected on a rare occasion? Or should it plainly NEVER happen?

[JPG]

Where was the blade backup bearing?

Did it break at the weld?

Was it a SS blade?

[lilgodwin]

The backup bearings about 1/32" behind the blade. Almost certain its a SS blade, came opened with the Shopsmith when I bought it. And no it didn't break at the weld.

[jsburger]

The backup bearings about 1/32" behind the blade. Almost certain its a SS blade, came opened with the Shopsmith when I bought it. And no it didn't break at the weld.

How old was the blade? If very old it probably was not sharp. That will make a difference if you force it.

Most of us are frugal and we don't want to replace things that seem to work. Blades of any kind need to be SHARP regardless of their intended use. Replacement or sharpening is required.

I think band saw blade breakage should be a rare occasion. FWIW, I have never broken a band saw blade.

[ERLover]

I have never had a BS blade break on me. With that said I was ripping a 5 ft piece of White Oak on my BS and towards the end of the cut I had difficulties finishing the cut. The Kerf was closing do to the nature of the grain of that piece of wood. I had to stop and put a wedge in the kerf to open it up and proceed. I dont know if the blade would have broken, it seems they want to break when cutting to tight of a radius then that size blade can handle. But I have no experience with that either, since I never had one break on me.

[lilgodwin]

Thanks jsburger, I appreciate that.

Well, I figured out the primary reason it broke. Not afraid to admit it when I do something wrong, stupid even.

Up until this point, I had been using the bandsaw for quite large pieces, resawing and such. So the fact that I was missing the table insert that surround the blade wasn't as crucial.

The piece I was cutting was smaller this time. And to keep small pieces from sliding down below the table, I placed some duct tape on both sides of the blade to act as a barrier.

Well I didn't think about another function of that plate being there. It also seems to be used as a backup for if (when) the blade catches the wood and really pulls it down. And wouldn't you know it, that's what happened.

Blade caught the wood and pulled it down through my impenetrable duct tape barrier. The rest is history.

Since I don't have this piece (yet), I cut a piece of plywood to shape and clamped it down over top the table as a temporary surface... One that covers the table AND the hole. Made a few more cuts with that in place and all is well.

Will certainly be ordering that insert.

Though I'm sure very few people would make that mistake, operating the bandsaw to cut small, or even medium, pieces without the insert in place, I'm hoping someone will learn from my mistake if they come across this.

Live and learn. Thankfully all my fingers are intact.

[JPG]

1/32" is excessive clearance.

[robinson46176]

I have never broken a blade on a Shopsmith bandsaw nor on another old bandsaw I used to have. Well, actually I still have it, just not in the shop. It is a very old Shopmaster, about a 10" I think. It looks just like this one but has been painted bright blue.

WS - Shopmaster bandsaw like mine.jpg (79.39 KiB) Viewed 5437 times

I did break a few blades on a truly ancient old industrial bandsaw i had many years ago. Picked it up at a selling out auction of a local contractor. It was huge and really heavy. The blade wheels were 24" and the equally ancient 2 HP motor weighed a couple of hundred pounds. The whole thing was 8' tall. It was originally made to be ran by an overhead line shaft. Like many old industrial machines being used by local contractors any kind of cage or guard was long gone if it ever had one. I built an 8' table on each side and was mostly using it as a small sawmill. The first time a blade broke and came slamming down across the table I built a wooden box guard for it, right after I changed my underwear...

[lilgodwin]

1/32" is excessive clearance.

Yeah, agreed. It's a good thing I lied. [emoji1] I actually checked after I wrote that. The guides are closer than that. They're all but touching.

[JPG]

1/32" is excessive clearance.

Yeah, agreed. It's a good thing I lied. [emoji1] I actually checked after I wrote that. The guides are closer than that. They're all but touching.

I was NOT referring to the blade guides, but rather the blade backup bearing. All but touching is best there as well.