Dumb question - Does all blade steel weigh the same?

Steelhog

Steelhog

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Ok Dumb question - Does all blade steel weigh the same or basically the same? Don't grill me too hard on this one. lol. I'm sure by the industrial sheet its different but in terms of 1/8" thick on 4"-6" blades is there much of a difference?

So for example I have 2 exact blade blanks - one in 3v and one in say 1075. Will one be noticeably more heavy? Are there some blade steels that offer a significant weight advantages? Thanks for the help!
 
Larrin said:
The density of steel changes slightly depending on what alloying elements are added. For example, aluminum is a very light element and tungsten is a very heavy element. Rex 121 is 0.298 lbs/in^3 and 15V is 0.262 lbs/in^3.
http://www.crucible.com/PDFs/DataSheets2010/ds121v1 2010.pdf
http://www.crucible.com/PDFs/DataSheets2010/ds15Vv1 2010.pdf

Edit: I missed the obvious high density steel, T1 with 18% W. 0.313 lbs/in^3
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Having worked with tungsten carbide anvils (in massive cubic hydrollic presses) I can say, I'm not surprised it has a noticable effect on the density of alloys!
 
Larrin said:
The density of steel changes slightly depending on what alloying elements are added. For example, aluminum is a very light element and tungsten is a very heavy element. Rex 121 is 0.298 lbs/in^3 and 15V is 0.262 lbs/in^3.
http://www.crucible.com/PDFs/DataSheets2010/ds121v1 2010.pdf
http://www.crucible.com/PDFs/DataSheets2010/ds15Vv1 2010.pdf

Edit: I missed the obvious high density steel, T1 with 18% W. 0.313 lbs/in^3
Click to expand...

So at 1/8" thick, 5" length, and 1" height (easy math), and we'll assume it's a cleaver because I'm not into the geometry of a spear point at the moment, thinking of a 5" Kephart pattern, we would be looking at 0.625 in^3. using the steels above, 0.18625 lbs (84.5 grams) for Rex 121 and 0.16375 lbs (74.3 grams) for 15V. Pretty minor on a small blade, but it adds up if you start looking at a 1/4" thick 10" chopper (4x the difference) at about 40 grams or 1.4 oz (some rounding error in there). Not substantial but in the realm of being noticed I think as you start to around the 1 lb mark for a knife.

I think this does confirm what I've been suspicious of since enjoying bigger handled knives, that handles can add substantial weight to get the ergos right, like LT Wright's knives. I've started becoming curious if makers are able to do stuff with plastic, like mora handles, as a lightweight backpacker option. Or, paracord wrap on a blade blank I suppose.
 
I just looked at the stainless steel composition chart on AG Russell's site. It looks like, other than chromium, most other metals in the alloy are less than 2%. Most less than 1%. So chromium is the alloy metal that would have the greatest effect on steel density, as it is greater than 12% in stainless steel. I didn't see any stainless steels with greater than 20%

According to my cursory research, iron's density is 7.87 grams per cc. Chromium's density is 7.19 grams per cc. Other metals, at less than 1% of the alloy don't count for much weight differences. Molybdenum is 10.28 g/cc, but only accounts for less than 1% in most steels. (Curiously, CPM-154 is 4% moly) Vanadium is light, at 5.8g/cc, but percentagewise, in the steel alloy, is again, usually less than 1%. (4% in M390)

Gold and mercury are much heavier. But they aren't used much in steel.

It looks like, if we substituted air bubbles for all the alloy metals in stainless steel, it would be about 2-4% lighter. If you took out the chrome too, you could have non-stainless steel with 15% voids (bubbles), for a 15% weight reduction.

I'm not a metallurgist. Just someone with a little time. So I could be completely wrong.
 
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steelhog said:
Ok Dumb question - Does all blade steel weigh the same or basically the same? Don't grill me too hard on this one. lol. I'm sure by the industrial sheet its different but in terms of 1/8" thick on 4"-6" blades is there much of a difference?

So for example I have 2 exact blade blanks - one in 3v and one in say 1075. Will one be noticeably more heavy? Are there some blade steels that offer a significant weight advantages? Thanks for the help!
Click to expand...

No, a 5lbs blank of s35vn will weigh 67% more than a 3lbs blank of 420hc. :D

I don't think, once cut/ground, the various densities of steels would make enough difference to factor into your decision of steel type.
 
Not a dumb question at all. If you use iron as standard for steel density, then the difference from steel to steel is the alloying elements. Since Chromium, manganese and vanadium are all lower density than iron, the more of all of these a steel has the lighter it will feel. Can you actually tell? Probably not. Cobalt and Tungsten are both higher in density than iron. So a high Cr stainless steel that has vanadium and manganese will be lighter than a basic carbon steel like 1075, but not sure you can tell the difference. A high cobalt or tungsten steel will weigh more than a basic iron steel but again, not sure you could tell the difference.
 
He said "basically " so not not that you would notice. However it you want to get technical yes.
 
Oh man, this opens a brand new avenue of pickiness for people who put high value / focus on the weight of their knives.

“I really like the design, but I wish they had used a lighter steel. 20CV brings it over my 1.3592oz rule for EDC.”
 
LG&M said:
He said "basically " so not not that you would notice. However it you want to get technical yes.
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Not sure if you are responding to me. I was responding to OP. Wasn't being technical just giving an opinion, so not sure what you are talking about.

As for yes or no to feeling heavier, that will very from person to person. I can tell you that my Kit Carson Stellite 6K U2 felt way heavier than the stainless version and they were identical in every other way. But that is a 80% cobalt alloy approx.
 
Cobalt said:
Not sure if you are responding to me. I was responding to OP. Wasn't being technical just giving an opinion, so not sure what you are talking about.

As for yes or no to feeling heavier, that will very from person to person. I can tell you that my Kit Carson Stellite 6K U2 felt way heavier than the stainless version and they were identical in every other way. But that is a 80% cobalt alloy approx.
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I was referring to the OP, he said basically. You might be more sensitive to these things then I but all else being equal I don't think one steel to another would be noticeable.
 
LG&M said:
I was referring to the OP, he said basically. You might be more sensitive to these things then I but all else being equal I don't think one steel to another would be noticeable.
Click to expand...


Yeah, I can see how he would think that. I do believe that there are people that could tell a minute difference in weight and then there is some that probably could not tell a difference in several ounces .
 
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