Sparks on bandsaw

The blade teeth were hitting the guide bearing, to tight a turn in such a thick piece. You may need to set the guide bearing back a bit more…BC

Might also be mineral deposits in the wood.

-- The nicer the nice, the higher the price!

Having no experience, and essentially no knowledge of band saws except they cut stuff, 20,000lb/square inch sounds like an insane amount of force. That is a normal tension?

could be sand on the wood or embedded in it

-- wchips

My old Craftsman 12” has guide blocks on each side of the blade. If I cut too tight a radius in wood, according to the thickness, the blade teeth sometimes will contact the guide blocks in a way to throw sparks.

-- http://wddsrfinewoodworks.blogspot.com/

In response to TimKane2 – - I’ve read from several sources that 20,000 per square inch is right. You need to realize that a 1/4” blade has a cross section that is a very small percentage of a square inch. My calculations say that it is about .55% of a square inch. That implies a total pull on the blade of 110 lbs. That sounds reasonable to me.

-- Rich, Cedar Rapids, IA - I'm a woodworker. I don't create beauty, I reveal it.

Where exactly are the sparks originating from?

I saw sparks one time, when the blade broke and flew off, not fun
Actually had that happen with mineral deposits.

-- E J ------- Always Keep a Firm Grip on Your Tool

I had sparks when my lower thrust bearing siezed.They obviously were below the table but the upper thrust bearing siezing would generate sparks above the table.I studied all the blade tensioning advice and use the 1/4” deflection and or the flutter technique.These have both been effective and simple to perform.You should be able to cut a much tighter radius with a 1/4” blade so I dont think that is the problem.I routinely cut 1” diameter circles with my 1/4” blade.

-- " I'll try to be nicer, if you'll try to be smarter" gfadvm

Rich,

I had sparks come from the guide blocks. But when I run a Carter Stabilizer with my 1/4” blade the standard guides and bearings, both top and botttom, are not used and the operation is much smoother.

-- Pops ~ In So Cal...

you might have banged the teeth into a guide or maybe your turn radius is too tight for the kerf and width of the blade or you might have popped the blade out from the guides while trying to negotiate the turn and it scraped the guides somewhere it ought not to.

-- When the moderator chooses sides, his site sucks.

Hi Rich ,My first thoughts were mineral content or foreign objects , but you don’t mention if the sparks are before entering or when exiting the wood , but I’ll assume they’re up top because it would be impossible to see below the table while slicing. That would leave blade contact with the guides or bearings and not much else that I can think of.
Sorry.

-- When did quiet and quite become the same word ? I'm guessing about the same time as your and you're did.

Rich, have to agree with Dusty 56, with out knowing where the sparks came from it is hard to provide a recommendaton. most likely I would check the lower guide blocks as they can come out of adjustment and because they are below the table, you may not have noticed.

Hope all goes well. good luck and safe sawdust.

-- Norm (AKA - The Maddhatter), Middletown DE

My band saw started making sparks at times and I found that one of the bearings had siezed. When cutting straight it was fine, but when trying to cut any kind of curve the blade contacted the bearing and caused the sparks. I changed the bearing and sparks went away.

Steve.