Bench Grinder Exhaust

[DrFeelGood]

First off, my apologies if this is an old topic or has been covered before. I seriously question my site search capabilities.
I recently added a 623E bench grinder to the shop and it came equipped with exhaust ports.

I am trying to figure out how to implement the exhaust capture feature. I have used silicone auto intake couplers for years to connect my shop vac to various tools and found that a 2" coupler fits perfectly on the oval grinder exhaust port.



I can then fit my non-standard 1.75in shop vac hose directly to the port coupler.



It is now easily possible to attach two 45degree 2in couplers and route both exhaust ports into a single line.
This single line can easily run along a 10ft silicone hose to a cyclone collection bin where I can plug into that as a port at the end of the bench.

Here is the question.

• Is it better to route the two ports immediately into a cyclone collector and then down the 8" of hose to the vacuum? <or>
• Is it better to route the two ports down a single 8ft hose to the cyclone collector then directly into the vacuum from there?

Will the metal in the cyclone that is close to the grinder be a bomb, or, will the slow accumulation of metal between the hose pleats turn this whole long tube into a roman candle?

My inclination is to have the two ports enter the cyclone collector immediately and then empty it regularly.

Thanks everyone for considering.

 

[isb cornbinder]

First off, my apologies if this is an old topic or has been covered before. I seriously question my site search capabilities.
I recently added a 623E bench grinder to the shop and it came equipped with exhaust ports.

I am trying to figure out how to implement the exhaust capture feature. I have used silicone auto intake couplers for years to connect my shop vac to various tools and found that a 2" coupler fits perfectly on the oval grinder exhaust port.



I can then fit my non-standard 1.75in shop vac hose directly to the port coupler.



It is now easily possible to attach two 45degree 2in couplers and route both exhaust ports into a single line.
This single line can easily run along a 10ft silicone hose to a cyclone collection bin where I can plug into that as a port at the end of the bench.

Here is the question.

• Is it better to route the two ports immediately into a cyclone collector and then down the 8" of hose to the vacuum? <or>
• Is it better to route the two ports down a single 8ft hose to the cyclone collector then directly into the vacuum from there?

Will the metal in the cyclone that is close to the grinder be a bomb, or, will the slow accumulation of metal between the hose pleats turn this whole long tube into a roman candle?

My inclination is to have the two ports enter the cyclone collector immediately and then empty it regularly.

Thanks everyone for considering

You have this figured out. I like the single hose a little better. The extra velocity should carry the debris better.

 

[Relax]

On another forum someone recommend automotive exhaust flex pipe out the back of the grinder. Maybe I don't understand your concerns about the metal accumulation in the silicone hose pleats becoming explosive. Are you also capturing sawdust in the same tube?

 

[DrFeelGood]

On another forum someone recommend automotive exhaust flex pipe out the back of the grinder. Maybe I don't understand your concerns about the metal accumulation in the silicone hose pleats becoming explosive. Are you also capturing sawdust in the same tube?

I have the idea that fine metal articles will settle out in the bottom of the hose pleats. My, "worst case scenario" brain sees this being ignited by a particularly exuberant ember and the powdered metal ignites.
House fires scare the poop out of me. I have seen what the event does to people and their lives. They seem to be forever marked by all life events being "before the fire" or "after the fire".
The house down the street just burned down from a garage fire.

So many people on here have much more experience than I do. I am just hoping that others will point out unreasonable fears or make recommendations.

The automotive flex pipe is a great idea. I had not thought about that but used it for years when tuning the truck in the garage during the cold winter months.

 

[seber]

Aluminum powder can make a great welding heat but I don't believe iron can do that. You certainly would not be grinding aluminum on a bench grinder.

 

[seber]

double post

 

[neophyte]

Aluminum powder can make a great welding heat but I don't believe iron can do that. You certainly would not be grinding aluminum on a bench grinder.

People sometimes grind aluminum on a bench grinder.
Lee Valley, in their newsletter years ago, even had an article mentioning the potential safety issue that could result if you grind aluminum, and you grind steel, and the two get mixed up, essentially making a thermite mixture, which might then ignite from grinding sparks.

 

[LopezBart]

you grind steel, and the two get mixed up, essentially making a thermite mixture,

Thermite is a mixture of ferric oxide (rust) and very finely ground aluminum powder. It's difficult to ignite w/o something pretty hot like magnesium ribbon.

 

[WWheeler]

We had sawdust ignite in our dust collector from an ungrounded hose coming from our wide belt/drum sander at a cabinet shop I worked at. Static electricity in ungrounded tubing can ignite sawdust, as we found out. Stunk the place up and got everyone sent home for the day. All of the dust collection got grounded after that to prevent it from happening again. I have no idea if metal poses the same type of risks.

 

[kaymccampbell]

When venting a bench grinder, or any spark generating device, you stick to metal tubes and isolated metal collection schemes. There is no way you'd get me to hook a mostly plastic shopvac rig directly to it. After the sparks traveled through a couple feet of steel pipe, and into a metal collection bin, with a screened outlet, then with a couple more feet of vertical up metal exit tubing, then I'd hook up a shopvac. And that shopvac would be dedicated to the grinder. Never mix metal n wood. Never **** where you eat. Just never.

 

[NORTON'S SHOP]

When I was making tooling back in the 80's our collection system was probably about 15-20 feet from each grinder. We shook it down every day, and maintained it with no exceptions. About once a year it would start a fire. Eventually, we ran the building's fire extinguishing system directly into the dust collection system.

 

[seber]

People sometimes grind aluminum on a bench grinder.
Lee Valley, in their newsletter years ago, even had an article mentioning the potential safety issue that could result if you grind aluminum, and you grind steel, and the two get mixed up, essentially making a thermite mixture, which might then ignite from grinding sparks.

There is a more immediate problem with grinding aluminum. It clogs the abrasive and makes the grinder useless.

 

[DrFeelGood]

Thermite is a mixture of ferric oxide (rust) and very finely ground aluminum powder. It's difficult to ignite w/o something pretty hot like magnesium ribbon.

Ah yes. This would explain its color.

When venting a bench grinder, or any spark generating device, you stick to metal tubes and isolated metal collection schemes. There is no way you'd get me to hook a mostly plastic shopvac rig directly to it. After the sparks traveled through a couple feet of steel pipe, and into a metal collection bin, with a screened outlet, then with a couple more feet of vertical up metal exit tubing, then I'd hook up a shopvac. And that shopvac would be dedicated to the grinder. Never mix metal n wood. Never **** where you eat. Just never.

That last line is always good advise. I am running silicone elbows along flexible exhaust tubing (8') to my cyclone collection bin. I think the idea of a dedicated vac is a good one. Thanks for that.

When I was making tooling back in the 80's our collection system was probably about 15-20 feet from each grinder. We shook it down every day, and maintained it with no exceptions. About once a year it would start a fire. Eventually, we ran the building's fire extinguishing system directly into the dust collection system.

Even with that maintenance schedule it gave trouble. I am understanding that it is dedicated metal as well.
I will by no means be using it in an industrial scale but mostly want to manage breathable particulates in a 2 car garage where I work and children are frequently playing (not while actively grinding) so I always consider their exposure.

I suppose I should also consider the whole idea of a residential grinder dust collector to maybe be unwise.

 

[neophyte]

There is a more immediate problem with grinding aluminum. It clogs the abrasive and makes the grinder useless.

There are grinding wheels made for grinding aluminum.

 

[neophyte]

Thermite is a mixture of ferric oxide (rust) and very finely ground aluminum powder. It's difficult to ignite w/o something pretty hot like magnesium ribbon.

One issue that comes up is with “mystery scrap metal” which people think is aluminum, but which is actually magnesium.
Magnesium used to be somewhat common, until is started to be used in the aircraft industry, and the price shot up.
Then a lot of manufacturers switched to using aluminum alloys.

 

[dutchgray]

I would pipe the whole lot to outside in a small storage box or similar where if it catches fire there won't be much harm done.

 

[humpty]

Back in the day our grinders in the shop were piped with exhaust flex pipe to little metal garbage cans. It was a simple solution that worked well.

After the millionth time of being cited every single time there was an inspection, the bench grinders were removed. Sad day, except for me as I got a free grinder.

 

[PBCampbell]

This above is the only way I've ever seen it done.

 

[Snapped-off]

Back in the day our grinders in the shop were piped with exhaust flex pipe to little metal garbage cans. It was a simple solution that worked well.

After the millionth time of being cited every single time there was an inspection, the bench grinders were removed. Sad day, except for me as I got a free grinder.

We take a safety hit if the plastic safety shields are up. Even when the grinder was stowed away behind a locked gate, unplugged. The shields were tightened down with loctite after that one.

 

[seber]

There are grinding wheels made for grinding aluminum.

I'd love to find one. Can you direct me to that? All I find are wheels for angle grinders.

 

[Nutria]

I personally wouldn't use plastic tubing or route to a shop vac. My approach is pretty bog simple: roll the grinders outside for use, admittedly not too appealing at night and in bad weather, but I can usually do something else if I don't want to grind outside at any given time. That wouldn't work if I were doing production, but it works for me.

 

[Busted Knucles]

Particles traveling through plastic pipe create static electricity. And the wrap pvc pipe with ground wire is not always successful.

 

[kbuhagiar]

I personally wouldn't use plastic tubing or route to a shop vac. My approach is pretty bog simple: roll the grinders outside for use, admittedly not too appealing at night and in bad weather, but I can usually do something else if I don't want to grind outside at any given time. That wouldn't work if I were doing production, but it works for me.

I thought I was the only one who did this. Great minds think alike, lol!
I have both of my grinders mounted on a rolling storage cabinet with a long built-in extension cord.
Primitive but effective...

 

[humpty]

We take a safety hit if the plastic safety shields are up. Even when the grinder was stowed away behind a locked gate, unplugged. The shields were tightened down with loctite after that one.

Same. The shields, the rest, the cord. It was non-stop. The lean guy swore that he could solve it, I told him it was obvious that it was operators not following procedure, but he figured he could TPM it away. He left a year later and the plant manager said just take them out, they are more trouble then they are worth.

Let's not even talk about air nozzles. Ugh...

 

[humpty]

There are grinding wheels made for grinding aluminum.

Yes there is but I would be reluctant to alter the notion that grinding aluminum on a bench grinder is bad, if you have a bunch of aluminum work just get a belt sander.
This is GJ after all and we should be encouraging a new tool purchase.

 

[MongoTA]

I have two of the same grinder. I have all metal exhaust.

I'd recommend you not combine a vacuum with a pleated paper or fabric filter or any combustable exhaust tubing with the metal grinders. A hot shard of metal stuck in a filter or hose combined with air flow could result in an immediate or delayed fire.

Check out auctions hear you. Bidspotter, for example. You might be able to pick up a proper vacuum on the cheap.

 

[neophyte]

I'd love to find one. Can you direct me to that? All I find are wheels for angle grinders.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Typically, Silicon Carbide, or a silicon carbide mix is recommended for aluminum.
There seem to be some other options as well on McMaster Carr’s website.

 

[PBCampbell]

I wonder if a "Fireplace" vacuum would work. They aren't terribly expensive.

 

[DrFeelGood]

I would pipe the whole lot to outside in a small storage box or similar where if it catches fire there won't be much harm done.

Maybe not right up against my cedar siding then...

I thought I was the only one who did this. Great minds think alike, lol!
I have both of my grinders mounted on a rolling storage cabinet with a long built-in extension cord.
Primitive but effective...

If I did not live in a suburban neighborhood with either retirees or families with small children, this might be an option. I am a bit like Switzerland here on my 1/3acre with a border that touches seven properties.

I wonder if a "Fireplace" vacuum would work. They aren't terribly expensive.

I was unaware of such a thing. Thanks for the tip, I'll look into it.

Time and time again I find my self saying how great this forum is.