The telltale etch.

Well ,my genius son has got it working:rolleyes: Dad's a dinosaur.
Anyhow, I won't repost whats in the new thread. Who has questions on etches? Do we want to keep this thread going or go to the shorter one?
Let me know and I'll try to keep up:confused:
Rex
edited because I kant type goud.
 
Originally posted by MJHKNIVES
I'm sure that there are many who etch for scientific reasons, but I believe RW hit the nail on the head, as to why a lot of makers etch,ie;"it's a quick and easy thing to do". What I find alarming is, there are a whole bunch of new makers who dont know how to put a good finish on steel,just sand blast it or throw it in the acid, which is why I found Nick Wheelers reply most refreshing. :D
Click to expand...

a polished blade will out cut BOTH an etched edge and a sandblasted edge
harley
www.lonesomepineknives.com


Edited by Blues to correct the (edited) quote attributed to MJHKNIVES.
 
OK Larry, you can't just come into this thread and make a statement like that without explaining what you mean. Do you mean that a polished blade will outcut an etched or sandblasted one, or are you actually talking about the edge as you stated. If you feel that a polished blade has this advantage please let us know why.

By the way, it is great to have you take part here.

You too Mr. Walter.
 
Originally posted by KWM
OK Larry, you can't just come into this thread and make a statement like that without explaining what you mean. Do you mean that a polished blade will outcut an etched or sandblasted one, or are you actually talking about the edge as you stated. If you feel that a polished blade has this advantage please let us know why.

if all things r equal
reduction in the friction
polished over the other 2
heres a another good one
a polished blade coated w carbon boron or ti will out cut a plain polished blade

i still sell lots of sand blasted blades
have etched some in the past
i,ve polished a freight train load of s.s.
and i hate it:)
it has no soul
harley
www.lonesomepineknives.com
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This is just plain unfair Larry!!! You best EXPLAIN this one in a little MORE detail.......Ira:eek: :eek: :confused: :confused:
 
Originally posted by wolfmann601 This is just plain unfair Larry!!! You best EXPLAIN this one in a little MORE detail.......Ira:eek: :eek: :confused: :confused:

ask specefic questions
i thought i explained it pretty good
its the reduction in the friction coeffecient that causes polished to cut better than etched or sandblasted
not talking about grinds or edges here
strickley finishes
all aspects of a knife and cutting r goverened by physics
its all physics
harley
www.lonesomepineknives.com
Click to expand...
 
Sorry it took me so long to get in here MO. I kept passing over this thread and finally had to look at it. Wow! Lots of good stuff covered so far.

I remember when I tried my first etch. It was on a cable damascus dagger I forged for Richard here at the forum. I had no idea what I was doing but it turned out pretty good anyway. I can't even remember where I first read about etching, but I got a handle on it in my usual way. Trial and error. I like the way Jerry Hossum said it. It was a real 'eye opener' for me once I figured out how to do it right.

Etching has helped me tremendously with my forged blades. Especially when it comes to finishes. I used to forge blades and leave that 'as forged' patina on them. I thought it looked cool. Ron Claiborne (Bowie) emailed me quite a few times and even called me on the phone pleading with me to change my ways because the 'as forged' finish hides too many serious flaws. At first I was a little agrivated at Ron because it hit me where I lived. Knife making, after all, was my livlihood so it hurt my baby feelings and I thought he was just saying that my work was inferior. Well, Ron is a great guy and one that I have a great deal of respect for. So, I listened to him even though I continued to produce blades with that 'as forged' finish. Then I went to the ABS school. That changed everything for me.

With what I learned at the school and what Ron had been saying, I was armed to attack this whole 'mountain man' knife thing with some education and experience behind me. I started etching all of my forged blades. And I etched them at different phases in the forging process just to see what happened. It really opened my eyes. Literally. I was embarassed by what I learned. Had I been selling inferior blades before I discovered the etching secret? Quite possibly. And that is a very humbling thing to have to admit to yourself if you forge blades for a living.

What I discovered is what Ed said earlier. There were so many inclusions, heat risers, cracks and such in the blades I was forging that it completely changed my forging processes. What benefit is there to etching a blade? The way I look at it now, if your blade isn't etched prior to final finishing and handle/guard work, you're working in the dark (with carbon steels). I don't mean to attack anyone's methods here. Far from it. This is just what the etching process has done for me and my blade work. It's revolutionized it. It gives me such confidence in my blades and heat treating methods that there's no question about what quality of blades I'm putting out now.

I use a good bit of chainsaw chain damascus for blades. I forge the damascus myself and until I started etching it I didn't truly know how well I was doing with my forge welding. Chanisaw chain isn't easy to weld up. It has to be done in stages and it's easy to think you've got a good, clean billet by just looking it over after grinding off the scale. With etching, I can see problem areas that need more forge welding before I even start to forge the bar into a blade. I guess that's pretty basic when forging damascus. But without that step I would still be putting out questionable blades. All the time thinking I was doing fine. Oh sure, I would discover the flaws during the final etch to bring out the 'damascus pretty' look, but that's the wrong time to discover that your blade is a pretty piece of junk! And the worst part is that if you continue to forge on a bar with inclusions, they just get worse as you stretch the bar out with normal forging. And you wind up with a hard earned piece of scrap damascus. Hard medicine.

I don't etch stock removal blades. Mainly because I don't use the stock removal process for my blades any more. But I would still etch them so I could see how well my heat treating went. And this may be off topic, but I'm going to say it anyway. I used the stock removal precess for almost 5 years before I started forging. I always got my stock from Sheffields and Admiral Steel. But I had no idea what the grain structure was in the steel when I got it. So, I wound up grinding a blade from stock that I knew nothing about as far as it's production methods, temperatures and what not. So, if I were to go back to the stock removal method I'd do things different. I would triple normalize and anneal each blade prior to heat treating. How would you know what the grain size was otherwise? I guess you could etch it before you started grinding on it but you still couldn't be sure unless you normalized it yourself could you? Just an observation that seems to tie into the discussion that's gone on here. Any opinions on my observation?

What a great thread KWM. Thanks for bringing up the question. Sorry I was so long winded. But I'm still pressing the 'submit reply' button :D
 
Larry: Good point: A heavily etched blade will have more drag than a polished blade. It is a matter of degree, the heavier the etch, the more drag. A light etch that is then polished will have significantly less drag than the heavily etched blade. It is a matter of infinite degrees, the smoother, the less drag. All etched blades are not equal. If pretty is more important than cut, the heavy etch may be what the client wants.

I prefer the light polished etch. I find very little difference in the cutting ability of a light polished etch blade compated to a polished blade. The light polished etch reveals the all important nature of the steel. I don't have to rely upon the makers word. Not that the maker is trying to deceive, if he honestly etches his blades, seeking the knowledge that can be gained, both he and I know, or have insight into the true nature of the blade.

Max: Your response was a trip down memory lane. Like Max, I learned very early that we cannot assume anything about the forged blade, or any other blade for that matter. All factors of performance are based upon the makers ability to truly know what he makes. Etching is only part of the story, it's significance is dependant upon the nature of comparison testing blade performance by the maker. When this knowledge is backed by laboratory examinaton the significance of these facts grows exponetially.
 
Larry, if you are going to quote me, I would appreciate it if you did not add a paragraph to the quote that I did not say. Thank you.
Edited in the intrests of rationality.
 
MJH:

The quote above has been edited by me and now accurately reflects what your (previously edited) quote stated.
 
Well, this discussion is really heating up again. I would like to get something cleared up and hope to get Rex involved in this thread by asking this question. In a previous post by Ed Fowler, he mentioned something called the Bausinger effect.

The greater insight we can gain, the more comprehensive our understanding. Etch does possibly increase corrosion resistance, more importantly, fine grain structure increases corrosion resistance and structural stability. You can gain insight to the grain structure through reading the etch.

All things being equal, a coarse grain will be more subject to the Bausinger effect than will a fine grain at the same hardness.
Click to expand...

I would really like an explanation as to what the Bausinger effect is. Hopefully some others are interested in this as well.
 
This is an excerpt I found on the Bausinger effect. It was in reference to oil pipeline:

The Bausinger effect is significant to SET research. Essentially it says that when a material is plastically deformed in one direction it will have les resistance in the other direction than it had originally. In other words, when tubulars are expanded, the collapse resistance – the opposite direction of expansion – of the final product will be less than the original tube. As a result, the collapse rating of expanded pipe is a hot button issue on which both companies are spending considerable time and effort.

I'm not sure how it applies here but that's all I could find on it. Maybe Ed will chime in here and remove the mystery.
 
Originally posted by MJHKNIVES
Larry, if you are going to quote me, I would appreciate it if you did not add a paragraph to the quote that I did not say. Thank you.
Edited in the intrests of rationality.
Click to expand...


i didnt add anything to your quote this system did
i was trying to put my answer below your question and
the system made the type look alike


stop and think!!!
am i dumb enought to do that on purpose and think i could get away w it
duuuuh!
lighten up
u need less stress in your life
go fishn and don,t take bait
harley
darth possum
www.lonesomepineknives.com
 
I think that the significance of the bossinger effect in knives could best be seen in the brass rod test. As a bar of steel is drawn out and down to make a knife then by virtue of the Bossinger effect the blade wil gain strengh in the direction that it is being drawn in. So by the Bossinger effect the strength of the blade will diminish in the direction perpendicular to the cutting edge. This can be show in the brass rod test. Ed and I have been able to reduce the significance of the Bossinger effect through the use of low temp forging and multiple thermal cycles.

Bill
 
Briefly on the Bausinger effect. When you look at steel in the microscope, fine equiaxed grain looks like a handfull of gravel. It has very few straight grain boundries. This is part of what gives it good strength. As steel is forged or rolled out in one direction, the grain elongates. It starts to lose the randomness to the grain boundaries and in extreme cases starts to look like a poorly laid brick wall. The grain boundaries get longer and start to " stack up" so to speak. The bad news comes in when stress is applied,you have ,in effect,created a path that the stress force will follow.
Everyone has seen a cement block wall that settles and starts to crack along the morter joints. Its about the same thing.NOTE ,in industery this is dealt with by various annealing and heattreating steps during the processing. In the oil tube industry the Bausinger effect is marked by a change in the ratio of the tensile properties, yield to ultimate strength. If anyone wants to know more I'll dig some refrence material out and post it tommorow/
Rex
 
rex
if u can find it
either post a link or post where it can be found
that is also the reason for the difference in cuting
when s.s. knives r cut from the plate horozontal or vertical
with the edge
all forged to shape knives follow the grain of the steel
not so w stockremoval
harley
www.lonesomepineknives.com
 
1. Thanx to all for the wealth of knowledge.
2. A request.
Would it be possible for someone to post some pics of etched blades, both good and bad? Especially the bad/reject blades. I think it would help alot of us understand more.
TIA,
Ebbtide
 
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