"Wood" dust collector for metal dust?

"Alex" wrote in message news: snipped-for-privacy@g44g2000cwa.googlegroups.com... | I just got a new G9975 Shop Fox 2 HP Dust Collector. |

| | I am going to use it with my 2"x72" belt grinder and grind mostly | carbon and stainless steel but dust collector manual says "for WOOD | dust only!" | | Is this "WOOD" dust collector going to have a problem with metal dust?

Construction of the equipment notwithstanding, wood dust is highly explosive, and introduction of a hot chip into the dust is truly an awesome thing to see. You can use appropriate ducting material and let the exhaust from the grinder dump into a bucket, or for positive evacuation, I've seen small shop vacs used, and you can get an additional device that turns on the vacuum when you turn on the grinder. Any material that creates a spark when grinding is not compatible with explosive dust mixtures. Even if you don't get sparks into the mix, the steel will make contact with the moist wood, start rusting, and if packed in tight, can start a fire all on its own, sped up by the wood with a lower temperature ignition point. You never want a pile of metal shavings or dust to get damp.

The flow rate is too low for pulling metal dust about except for the very fine stuff. IN addition, as the other poster said, the collection systems are usually plastic as well as cotton bags and filters and that stuff doesn't like being hot.

-- Why do penguins walk so far to get to their nesting grounds?

What is the "right" dust collector for metal work? Flow rate of my dust collector is 1550 CFM. Isn't this enough?

Based on your guys suggestion I'll put a metal bin with a precollector instead of vertical bags it came with and vent exhaust outside.

BTW What kind od ducting I should use? Aluminum won't wok too good because it's a mobile setup and I'll have connect/disconnect and move to/from storage it every time I use it.

Thanks for all suggestions, Alex

If anything, you need to use a metal body shop vac that can safely contain a fire. If you try using a workshop piped dust collection system designed for woodworking to do both wood and metal clean-up have water hoses and extinguishers on hand, and make sure your fire insurance is paid up.

Besides the problems that have been mentioned already with hot sparks from the grinder in the same bag house with wood dust, and the moisture from the wood flour causing steel fines to oxidize and catch fire, there is a third hazard that you create when you suck up the grindings from a bench grinder or use a belt sander on metal - take steel fines and aluminum fines, mix them together, and you have Thermite. Does mot take much to set it off...

Keep the Wood Shop and the Metal Shop seperate.

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Well, no, you WON'T have thermite, that's aluminum and iron oxide. but finely divided metals are a hazard by themselves, fire and explosion. We had a local knive maker's operation burn completely to the ground when light alloy grinding dust caught fire in the dust collection ductwork. Had been in business making cast magnesium alloy-handled steak knives since before my folks were married. Now it's just a vacant lot. Nuf said.

Stan

I'm thinking of doing much the same thing for my little Sanford 4"x8" Surface Grinder.

However, the device will NOT be used to do double-duty .. it will be a dedicated device for Surface Grinder use only.

The plan is to build a little hood at the end of the table, with a hose going upwards to a typical blower/sucker.

(All the commercial units seem to try to catch the dust right at the wheel, for reasons that escape me; by catching it 6 inches away, much of the velocity of the particles has been lost, making them much more likely to be captured .. or so it seems to me)

Initial tests using a _small_ Shopvac showed this to be almost 100% efficient in capturing the dust, just darned noisy .. too noisy.

A portable dust collector setup should get it all, with much less noise.

What I'm not sure of is what to do with the exhaust. I could just dump it outside, but that seems like a waste of hot air in the winter; these things move a lot of air.

So I'm left putting some sort of box and filter on the outlet. I'm thinking about a small version of the "swirl" type of units (using maybe a 5 gallon bucket instead of a garbage can, for all the dust that this little grinder will create) with the outlet of the swirl attached to the largest practical automotive air filter.

I'm also thinking about putting an inch of water in the bucket, to maybe catch some of the dust that way.

Any thoughts ?

Thanks in advance.

Alan

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Be certain that the sparks that come from the grinder can't ignite anything. Vacuum cleaners with filters are subject to fires from grinding sparking materials. The use of water in the chamber will help, but it will also introduce a lot of moisture to your shop environment, so if you have rusting problems, they're likely to be enhanced.

Harold

A few years ago while I was working on my surface grinder, I spoke to a service tech at Boyar Schultz. We discussed my cleaning of the vacuum base for the grinder. It is equipped with cloth filter "bags". He cautioned me not to wash the bags, as they were treated with a fire proofing / flame retardant material. He stressed this point more than once, recounting his experience with fires in this unit.

John Normile

I fully agree - fire retardant. The bags are open bottom and fall into a pull out tray. The air goes through the bag and finally routs outwards.

Martin

Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

John Normile wrote:

According to Alan Rothenbush :

Does your Sanford have the little vertical partition at the left end of the table? It seems to stop most of the dust, but no all. Would you be hitching the intake hose to that partition?

Enjoy, DoN.