Second incident with smoke under my CBN grinding wheel

[Bob Bergstrom]

I use a magnet under my CBN wheels and it had accumulated grinding dust on it. Also in the mix was wood chips and some sanding dust. After sharpening my bowl gouge I smelled smoke in the my shop. Not a good thing to smell. Looking under the wheel I could see a glow. Because there are no guards on my wheels the spinning of the wheel caused a fanning of the mixture and assisting in igniting the dust and fine grinding powder. I did not see a flame but it wouldn't have taken too much more material to start a small fire there. This is the second time I have had a glowing of grinding dust start to combust. Bottom line is make sure to keep the area below and around your CBN wheel clean of both ginding dust and sanding dust.

[Reed Gray]

Well, this is the first time I have heard of that. I tried the magnet, and it didn't work all that well, and I just sweep the steel dust into the shavings. It is organic I guess. Most of my wood is too wet for this to be a problem, but that stuff does dry out. I did have one smolder problem on my Laguna bandsaw with the ceramic blade guides. Had a bit of dust build up by the guides, and they do create a few sparks. It was smoldering, and fortunately didn't go down the dust collector. I have seen special vacuum systems for grinders, but agree that keeping it clean is easier and cheaper.

robo hippy

[Harry Robinette]

Bob
I just got my CBN wheel and have had the same little smoke thing happen but behind the grinder. I put a piece of sheet metal under the wheel and then bent it up the back of the wheel to about 2" above it. This stopped the hot sparks from going everywhere and landing in saw dust.
Didn't think of the magnet I have some sheet magnet I might but under the wheel.

[Steve Schlumpf]

I'm with Reed on this... first time I have heard of it happening. I usually keep the area clean but will make sure to pay attention from now on! Thanks for the heads-up!

[John Keeton]

This is the main issue I have with sharpening stations close to the lathe. Mine is on the other side of the shop - the short walk of 5-6 steps is a good safety feature, and I need the exercise! I clean up after every turning and part of that clean up is to blow away all dust around my grinder.

[Roger Chandler]

+1 on what John said! I regularly blow all particles away from my grinder and vacuum up chips, sawdust and curlees......the last thing I want or need is a shop fire........whatever I can do to try and prevent such an occurance is what I will do...........one thing to especially watch out for is the accumulation of finishing rags as well.......they can spontaniously combust and that has caused a lot of shop fires.......be careful out there!

[Reed Gray]

I kind of wonder how you can generate enough sparks to start a glowing ember. Most of the time, I see almost no sparks at all. Guess the same can be said for the ceramic guides on my bandsaw as well. Oh well, always keep a fire extinguisher or two handy, and keep them updated, just in case. Heard of one woodworker who had a cigarette butt get sucked up in the DC and he lost his brand new shop. Maybe a fire extinguisher discharged into the DC would have stopped the fire if he caught it in time. Of course, no smoking any where near the shop is the smart thing to do.

robo hippy

[Harry Robinette]

I keep my shop pretty well cleaned up. But no guard on that wheel with sparks, somethings going to happen.I just want people to know we all
need to watch these wheels. If our shops clean or not and like John K said were we put the grinder can make a difference.

[Jeffrey J Smith]

Been using my CBN wheels for a while now, and haven't seen smoke rising. I had a couple of magnetic strips from one of those magnetic tool holders for peg boards that I wasn't using. Put them on top of the Wolverine base (covered the top of the whole base) under each wheel. Nearly all the grinding dust is captured. I just pull them through a paper towel occasionally to clean. My grinder sit right next to the lathe, at the headstock end. It pretty regularly gets shavings...I'm going to be a little more aware, and perhaps a little cleaner.

[Bernie Weishapl]

I did like Harry R. did on his and made a sheet metal container to catch the filings. Like John mine is not setting next to the lathe but across the shop.

[Michelle Rich]

this is one of the reasons I use a slow water wheel... stuff like this can smolder & catch hours after one has left a shop...

[Brian Tymchak]

I did like Harry R. did on his and made a sheet metal container to catch the filings. Like John mine is not setting next to the lathe but across the shop.

Harry, Bernie, could I trouble you to post a picture of the metal containers you fashioned? Seems like a pretty reasonable safeguard to do. Thanks for the great idea!!

Brian

[Brian Libby]

I have had many a glow start by the grinder BUT only after heavy grinding.

[James Combs]

This is the main issue I have with sharpening stations close to the lathe. Mine is on the other side of the shop - the short walk of 5-6 steps is a good safety feature, and I need the exercise! I clean up after every turning and part of that clean up is to blow away all dust around my grinder.
+2 on John's comments. Regular cleanup and a walk to stretch my legs. But just in case I do have a fire extinguisher just inside the entry/exit doors.

[mark ravensdale]

Like some of the other guys have mentioned, I try and be fastidious with regards to cleaning before I do any grinding or sharpening, my workshop is tiny so I make sure I have vacuumed up all the dust and shavings I can before the grinder comes out.
i have been using a CBN wheel for around 6 months or so, and one of the first things I notice was how few sparks were generated as compaired to my 100grit alu ox wheel which it replaced, but even so I am still very carefull (sparks and wood dust/shavings are NOT the best of playmates (though given a chance they will get on like a house on fire!!!))

Take care guys (really!!!)

[Jeffrey J Smith]

Bob, you didn't indicate whether you're using a slow-speed grinder, or standard speed. Unless I'm using the 80 grit for reshaping, I've seldom seen sparks generated from the 180 where I sharpen most often. It's even hard to see sparks traveling down the flute, which I used to use to indicate I've gotten to a sharp edge. Are you guys that are seeing smoke using a high speed grinder by any chance?