Wrench Knives?

C

CaptainFish1

Joined
Jan 1, 2019
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Hello, I'm relatively new to making knives, forging, and metalworking in general, so I'm not the best with metallurgy. I've been wanting to begin forging blades for many years now, and I've decided to start my first project by forging some blades from wrenches. A while back, I was given a box of combination wrenches from Craftsman, Allen, and other brands that went up to around a foot long, and I decided to try and forge a couple of blades or tomahawks using them (some of which I've seen YouTube videos on). However, after some digging, I found out that they were steel with a chrome plating, and when chrome is subjected to high temperatures, it releases fumes that are bad for the human body. I was wondering, could I simply forge these wrenches at a bright yellow heat without problems, or would I have to de-chrome them prior to turning them into blades? And if so, how would I go about doing that without using expensive chemicals like acids?
 
I used to run an industrial chrome stripper at a prior occupation and the chemical bath we used was water/ hydrochloric acid. It worked rather quickly.

In a hobbyist setting I am not so sure. I tried before using acetic acid (vinegar) with no luck even letting the wrench soak in it for weeks lol.

I would just go to a flea market or garage sales and look for real old wrenches - maybe even with some rust on em' - and no chrome.

I wouldn't just try to 'burn off' the coating. Some blacksmiths do that with galvanized steel and they are playing a very dangerous game. Metal fume sickness can kill you.
 
allenkey said:
I used to run an industrial chrome stripper at a prior occupation and the chemical bath we used was water/ hydrochloric acid. It worked rather quickly.

In a hobbyist setting I am not so sure. I tried before using acetic acid (vinegar) with no luck even letting the wrench soak in it for weeks lol.

I would just go to a flea market or garage sales and look for real old wrenches - maybe even with some rust on em' - and no chrome.

I wouldn't just try to 'burn off' the coating. Some blacksmiths do that with galvanized steel and they are playing a very dangerous game. Metal fume sickness can kill you.
Click to expand...

Zinc fumes will not kill you, thy won’t even leave lasting affects. People need to stop spreading rumors.
 
JTknives said:
Zinc fumes will not kill you, thy won’t even leave lasting affects. People need to stop spreading rumors.
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Can you, with 95-ish% certainty, say that this is a rumor?



http://www.anvilfire.com/iForge/tutor.php?lesson=safety3/demo


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Paw-Paw 1940 - 2005 Well folks. This is a hell of a way to do a demo. I did something stupid that I knew better than to do, thinking I was tougher than a little smoke. Well, I miscalculated and now I am dead.

My friends will have to finish this for me. . .

Sheri, I love you. Please forgive me.
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Figure 1 We will never know what Jim was thinking that day. He was probably just trying to get a job done the quickest easiest way he knew how.

The parts to the right were 2.5" galvanized pipe. They were to be welded up as part of a stock rack we think. To weld them they needed the galvanizing removed.

Jim burned off the zinc in his gas forge.
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Figure 2 Burning zinc looks similar to burning magnesium. It flares off white zinc oxide smoke and leaves heavy soot like yellow and white oxide deposits where the smoke cools. In the metal working shop we are often exposed to small amounts of zinc smoke without ill effect. It is common in brazing, casting brass and ocassionally welding.

However this was not a small amount of zinc smoke. It was thick enough in his well ventilated shop that Jim wisely sent his helpers outside. Why he stayed we will never know.
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Figure 3 There was so much zinc that it reacted with the refractory lining causing the ITC-100 coating to flake off. Around the door gasket area there were 1/16" thick deposits of zinc oxide. There is no question that Jim was exposed to significant amounts of zinc oxide smoke as he removed the flaming parts from the forge and quenched them.

Two weeks later when the forge was fired up it was still generating zinc smoke and fumes.

After this event Paw-Paw was very ill for a couple days. He thought he was over it and went on a road trip. A week after the exposure he came down with double pneumonia and had to be brought home. A week later he was dead.

Prior to this Paw-Paw had problems with emphysema and this is a factor in his case. However, metal fume fever can kill the young and healthy or leave lasting effects.
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Scary stuff. And timely as I just read the other day here that zinc fumes effects are over exaggerated
Rip paw paw
 
I'm sorry for your loss. However, I'm not discussing galvanized steel, which I'm not sure where JT got the idea that it isn't dangerous from. I want to know, is the chrome plating a problem, or am I good to go with forging the wrenches?
 
allenkey said:
I used to run an industrial chrome stripper at a prior occupation and the chemical bath we used was water/ hydrochloric acid. It worked rather quickly.

In a hobbyist setting I am not so sure. I tried before using acetic acid (vinegar) with no luck even letting the wrench soak in it for weeks lol.

I would just go to a flea market or garage sales and look for real old wrenches - maybe even with some rust on em' - and no chrome.

I wouldn't just try to 'burn off' the coating. Some blacksmiths do that with galvanized steel and they are playing a very dangerous game. Metal fume sickness can kill you.
Click to expand...

Since I don't have access to muriatic acid, and I just have nearly a hundred wrenches sitting there waiting to be used, I was wondering if I could just use an angle grinder or a file to just file/grind off the chrome plating so I am left with a fairly safe piece of chromium vanadium steel to work with.
 
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OK, I think the confusion about Paw-Paw Wilson's death has long been cleared up - He died of pneumonia, flu, emphysema, and exposure to dense smoke and fumes in a closed up shop with no ventilation ... not zinc poisoning.

Zinc can be safely burned off and the fumes vented or blown away by a fan.

Chrome is a different thing, and is best ground off. Wear a good respirator. I would NOT recommend burning it off. You might be able to sandblast it off?

Dissolving chromium in acid or by stripping and disposing of the waste solution is very illegal. There are very strict regulations ( and fines) on chromium discharge.

Back in the late 1960's I invented a process for removing chromium from plating plant discharge water. The process belonged to my employer, so I didn't get more than a pat on the back, but I understand the owner made a lot of money selling the rites to the process.
 
He died of pneumonia, flu, emphysema, and exposure to dense smoke and fumes in a closed up shop with no ventilation ... not zinc poisoning.

Twas the Diabetes that killed Auntie Helga, not the soda pop. So drink up kiddies!

All of those were factors in his death, and he might very well be alive right now had he not been exposed to one more insult to his already taxed system.

I'm sure at one point on this very forum, some sage old timer scoffed at the mere mention of using a respirator to mitigate grinding dust.

Work safe, take precautions (even if they seem over the top to some crotchety old scab on the internet/job site), when in doubt read the MSDS, I guarantee you will not look back and say. "Gee, I really wish I hadn't worked as safe as I did. Hell I could have squeezed 10 more minutes of work out of my day."

That all being said, I have cut, ground, and welded miles of zinc plated uni-strut. I didn't know any better, and all the old timers said, "just drink some milk and you will be fine." More than a few times I went home feeling like I had been poisoned.

I have no lasting effects.

But what if?

I'm not saying don't.

I'm saying think it through.
 
If you read my posts over the years you would see that I always say to use good ventilation, avoid breathing ANY fumes, and wear a respirator all the time when grinding. I was once called the safety nazi (a more than humorous ironic statement) for always recommending proper safety and eye/lung protection as the first thing new makers should learn.

I was just, once again, setting the wives tale that zinc is poisonous to humans, especially in the form of fumes. The fumes are inert zinc oxide .... what we rub all over our kids in the summer and lifeguards wear 12 hours a day. Think about it - if there was any toxicity at all, it would be banned for such products.

Next week I will likely have to again assert that MOP does not contain cyanide and breathing the dust will kill you.

Now, Spanish fly .... well that is a real thing ... I read it on the internet ;)
 
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