FIRE HAZARD with CBN wheels

[Reed Gray]

That Baleigh DC looks nice for industrial purposes, but out of range for most home shops..... Hmm, maybe a call to them might inspire them. I will have probably 4 grinders in the new shop, but still don't need that kind of air flow...

robo hippy

[Van Huskey]

That Baleigh DC looks nice for industrial purposes, but out of range for most home shops..... Hmm, maybe a call to them might inspire them. I will have probably 4 grinders in the new shop, but still don't need that kind of air flow...

robo hippy

Mr. Hippy, or may I call you Robo... I have always loved that nick.

I didn't really search for a more hobby centric solution but I bet there are more reasonably priced ones, Grizzly has lots of metal working machines for example. I know Baldor used to make a simple one that mounted to the back of grinders, it looked like a small DC fan used metal ducting and had a bag that I assume was fireproof. They may still make it but it would still be expensive. But a HF DC, some metal ducting and one of these bags would seem to suffice. The popularity of bladesmithing has produced a ton of belt grinder builds on youtube and some have built associated metal dust collection systems.


I looked Grizzly ha s a couple this is one http://www.grizzly.com/products/Meta...ollector/G0818

The manual and exploded parts diagram might help reverse engineer one and allow someone to buy any parts that might be difficult to fabricate or locate.

[Dave Zellers]

This happens on my WorkSharp if I allow the metal filings to build up under the glass wheel. Ignites where the iron touches the sandpaper and takes about 5 seconds to burn to the other side. No smoke, just a red glow.

[Perry Hilbert Jr]

Friction is a hot lady with a mean temper. A few years ago, I was working on a piece of farm machinery Between the cleaning solution, steel wool, metal shavings and angle grinder, I managed to catch the lawn on fire. I do not do anything that creates sparks indoors. My shop grinder is on a wheeled stand and goes outside to sharpen tools. We already lost one house and shop to an electrical fire. We'll take no chances. I thought Mrs. was gonna kill the daughter for having a candle lit last Christmas.

[Reed Gray]

I have been chatting with Oneida (dust collection if you don't know...) and mentioned the problem we are having with metal dust. The clerk was not familiar with it, but said he would pass the info on to the engineers. We really need some thing affordable for the average shop. There is a shop vac in just about every shop.....

robo hippy

[Matt Mattingley]

This happens to me quite often. I keep a ketchup bottle with a pinhole filled with coolant. I just give it a little squirt when I see the little moving glow. The first sign of this starting is horrid smell. If you let it keep going it usually burns out.

This happens most with my surface grinder or my 12 inch fibre chopsaw. Sometimes I get little Christmas trees growing and they burn brightly at the top of the tree.

[Van Huskey]

I mentioned this to my cousin who is a bladesmith and he said either make a spark bong or use a Nordfab or similar spark arrestor.

The spark bong is a metal Dust Deputy on a steel trashcan with a few inches of water in the bottom.

[John K Jordan]

I mentioned this to my cousin who is a bladesmith and he said either make a spark bong or use a Nordfab or similar spark arrestor.

The spark bong is a metal Dust Deputy on a steel trashcan with a few inches of water in the bottom.

Someone sent me links to a spark bong a guy built. His first tries sucked the water out of the can. He reported that replacing the water with corn syrup worked better but didn't report on long-term use.

My 5hp cyclone will probably pull the head off a cat so I would have to experiment.

JKJ

[Eugene Dixon]

. ...pull the head off a cat...
JKJ

Now that's a vivid image!

[Dean S Walker]

First let me say thanks John for bringing this to our attention. I have worked with many metal shops and welded the first half of my life and I have seen plenty of glowing piles of metal from chop-saws grinders and belt grinders. My concern is using a dust collector that is used to collect wood simultaneously catching metal dust. Any dust will ignite, just ask the local grain elevator. Wood in small bits mixed with metal, I would be concerned about that. The problem is it could smolder for a long time before it burnt your shop down. That would be terrible, i'm sure you would agree. I would suggest a separate system for the metal dust or come up with some kind of filter barrier down stream. If your system will pull a cats head off it would pull air through a filter. Maybe a thien baffle, small set up, to a screen to a filter or system of filters to a blast gate. Just make sure no, zero metal gets to the impeller. Maybe a filter system could be incorporated on the outlet of the thien set up. I'm sure if one is already made Van will find it.

[Peter Christensen]

I found on Alibaba aluminium mini cyclones much like a Dust Deputy and they are cheap too. I posed the question of their use on an Aussie metal forum and the response was overwhelmingly “DO NOT USE THEM FOR STEEL GRINDING DUST!” The reason being aluminum and iron make thermite so even though unlikely it could become a nasty fire. So if you’re going to look for a metal cyclone for a grinder/sander make sure it is of steel or stainless steel and not an aluminum one.

The metal polishers at work worked on downdraft tables. When we first got them there were several fires in them when the sparks caught the big cartridges on fire. They replaced them with nonflammable filters and separated the steel, titanium and aluminum were done on different tables. So if you’re going to use intermediate filters to stop sparks make sure they are nonflammable or they could catch fire.

The best downdraft tables we had drew all the dust laden air through water into another chamber where it passed through water impinging filters to the impeller. Not sure how to make a version for home use.

[John Keeton]

This seems to be an overly complicated approach. Periodically I just take a damp blue shop towel and wipe up the accumulation of dust. Throw the damp rag in the trash and do it again as needed.

[John K Jordan]

This seems to be an overly complicated approach. Periodically I just take a damp blue shop towel and wipe up the accumulation of dust. Throw the damp rag in the trash and do it again as needed.

My long term goal is just like for wood dust: to extract the steel dust before the fine component becomes airborne. From observation it's apparent that if some accumulates some also floats around the shop in the air I'm breathing.

[John Keeton]

Well, I thought the thread was principally about the fire hazard from collected metal dust. But, it would seem you could do that with a DC intake located close, but far enough away that you wouldn’t have “hot” dust. But, perhaps not. In any event, I guess I will just have to tolerate that situation.

[Ron Rutter]

A friend built a miniature cyclone for use on his grinder. Worked great.