Warning, Warning, Warning Explosive mixture

Wayne Coe

Forum Owner - Moderator
While I was at Fred Rowe's house back in May, we were discussing grinding various materials.

I commented, "NEVER, EVER GRIND STEEL AND ALUMINUM ON THE SAME MACHINE OR USE THE SAME DUST COLLECTION SYSTEM". This also applies to wood or other handle material.

Steel filings and Aluminum filings are the two components of Thermite, and very powerful explosive.

Google Thermite and you will come up with bunches of hits.

Here we are not trying to make Thermite, we are trying NOT to make Thermite.

Several years ago I saw an article in one of my Blacksmithing Newsletters where a blacksmith had been grinding steel. Later his son came in and use his grinder to grind some aluminum. The next day the blacksmith started using his grinder again and was engulfed in a ball of flame. There were pictures of him in the article. Both hands and arms as well as his chest and face received 3rd degree burns. It is surprising how little steel filings and aluminum filings it takes to make a very violent explosion or very hot fire.

In April at the Batson Blade Symposium Dan Johnson of Steven Bader Company was talking about how they had advised a customer how to set up his dust collection system, which included directions about spark arresters, and distance from the grinder for the collection container and not to mix products. The customer took the cheap way and placed the container close to the grinder and mixed materials. The thermite exploded, leveled the concrete building and killed several workers. Wound up that it was not the cheaper way to do it.

Not only steel and aluminum should not be mixed, wood and other products also. Hot sparks from steel and wood dust can make a very mean fire and sometimes explosions.

Be careful and don't make Thermite in your shop!
 
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Wayne Coe

Forum Owner - Moderator
Ok, I agree, it should be a Sticky. Someone who know how please do it. If I have to tell me how.
 

Wood Stabilizer

Well-Known Member
While I was at Fred Rowe's house back in May, we were discussing grinding various materials.

I commented, "NEVER, EVER GRIND STEEL AND ALUMINUM ON THE SAME MACHINE OR USE THE SAME DUST COLLECTION SYSTEM". This also applies to wood or other handle material.

Steel filings and Aluminum filings are the two components of Thermite, and very powerful explosive.

Google Thermite and you will come up with bunches of hits.

Here we are not trying to make Thermite, we are trying NOT to make Thermite.

Several years ago I saw an article in one of my Blacksmithing Newsletters where a blacksmith had been grinding steel. Later his son came in and use his grinder to grind some aluminum. The next day the blacksmith started using his grinder again and was engulfed in a ball of flame. There were pictures of him in the article. Both hands and arms as well as his chest and face received 3rd degree burns. It is surprising how little steel filings and aluminum filings it takes to make a very violent explosion or very hot fire.

In April at the Batson Blade Symposium Dan Johnson of Steven Bader Company was talking about how they had advised a customer how to set up his dust collection system, which included directions about spark arresters, and distance from the grinder for the collection container and not to mix products. The customer took the cheap way and placed the container close to the grinder and mixed materials. The thermite exploded, leveled the concrete building and killed several workers. Wound up that it was not the cheaper way to do it.

Not only steel and aluminum should not be mixed, wood and other products also. Hot sparks from steel and wood dust can make a very mean fire and sometimes explosions.

Be careful and don't make Thermite in your shop!
Thanks for sharing this. I agree...this should be a sticky post.

Christina
 

Ironwolf

The Knife Poet
For those grinding multiple metals,and/or in an environment where there are more than one person grinding,
here's a possible solution: either have dedicated (clearly marked) grinding stations for specific metals,
or dedicated waste collection bins/collection systems...
 

LR Adkins

Well-Known Member
I learned the hard way, and have the scar to prove it. I was grinding aluminum and it had a bolt in it. The aluminum had piled up on the back of my hands as I was grinding and I hit the bolt sending sparks every where. Instantly my hands, covered with aluminum dust, where engulfed in flames. I tried to brush the fire off my hand and the flesh slid right off the top of my hand. That stuff burns hot and fast, and it doesn't take much to do a lot of damage. Be careful guys.

Larry
 
G

Gabe Newell

Guest
Yeah, I made accidental thermite in my dust collector.

I pulled it outside, and emptied an entire fire extinguisher into it, and it didn't slow down the fire at all.
 

smflorkey

Active Member
Thanks for the heads up on this one. Its not something everyone is aware of.
Indeed. We're used to thinking of metals as non-flamable. This is kind of scary; I hadn't thought of accidentally making thermite in our shops. And I certainly hadn't thought thermite is easy to ignite. I seem to remember high school chemistry (way back in the Dark Ages) saying thermite was hard to ignite but nearly impossible to extinguish. Kudos to Wayne for the warning! :35: (Now where can we find the old emoticons for fainting and thumbs-up? :3:)
 

Fred Rowe

Well-Known Member
Since I make both knives from steel and Bubble jigs from 6160 aluminum; in my shop, Wayne Coe stopping by in May, may have saved my life or at least one heck of a scare. I had never heard about Thermite and was completely ignorant of these facts. I did a lot of clean up around the shop after Wayne left and now I mark the belt that I grind with as either for aluminum or for steel, but never for both.
Yes indeed a sticky for sure.
Thanks again, my friend, for making me aware, Fred
 
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Logrus9

Well-Known Member
I think one of those "odd job" shows on TV showed them using thermite to fuse railroad track sections together. A few minutes of burning and the ends were fused solid.
 

Ironwolf

The Knife Poet
I wonder what a chunk of slag from some of that molten metal would look like as bolster material...
...(maybe if I start a very small Ti/steel fire?...) ;)
 

Sean Jones

Well-Known Member
Thanks for the heads up. I've known in the back of my mind that aluminum and steel make thermite but never considered that the shavings mixed together would be a problem.

I'm not telling my wife about this though :shush:
 

Ironwolf

The Knife Poet
Thanks for the heads up. I've known in the back of my mind that aluminum and steel make thermite but never considered that the shavings mixed together would be a problem.

I'm not telling my wife about this though :shush:
hmmm...hey DropPoint? if you were to send something shiny and sharp my way,I'll see to it she doesn't get an email to go look in your grinding area...:nothing: :3:
 

Wayne Coe

Forum Owner - Moderator
Fred does have a dust collection system and spark arresters (I think). I still worry about him and I suggested that he have an area dedicated to grinding each metal and dedicated dust collections systems for each. He has recently built a new grinder so maybe he can use it so set up the dedicated areas.

Don't forget the chop saw and grinding areas. I think that they should be in segregated areas so that flying sparks can not get into the aluminum or Ti, etc.
 
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