Edge Packing

AKADave

AKADave

Gold Member
Joined
Jun 21, 2002
Messages
152
A local Journeyman smith showed me a technique he used some years back he called "Edge Packing". If I remember correctly he would strike the blade along the edge (unfinished knife of course)while it was hot but not forging hot. He explained that this somehow compressed the crystaline structure making it capable of a keener edge and tougher. Any merit to this, I think I have heard more dissenting than affirming.
 
Wayne Goddard in his book "$50 Knife Shop" talks quite a bit about packing...or as he prefers to call it...a finishing heat.

I think that it was a technique that was used and referred to in old blacksmith manuals for making chisels and other cutting tools.

I still do it...because it is the way I learned it. At the very least, it smooths up the bevels before grinding. I use a light hammer and look for a heat that is dull red.

Greg Covington
 
Sweet looking knives on your site! I would love to have one of your camp/bowies. Thanks for the info.

Dave
 
I like to pack the edge too. I have found it packs better on the 3rd wednesday night of the month with a full moon just before midnight. Really it helps during the nornalizing heats to refine the grain after forging at high heat or forge welding.
 
Oh man, still laughing at Bruce's post... :D

"Edge packing" is one of those notions/processes that was passed down from generations...but (IMHO) it wasn't understood. The reason there would be any validity to it at all is because the guys that don't know any better and believe in it, do it at heats that are similar in nature to thermal cycles.

You will get a lot better results by following science and taking your steel through thermal cycles than you will through trying to magically transform it with a hammer.... :)

Best of luck,
Nick
 
I've gotta go along with Nick. The old time black/knifesmiths did wonderful things with the equipment they had...but...edge packing is a little like the dance I do to align all the atoms during forging. In case you are wondering, the atoms must be aligned for the edge to be sharp enough to split airborne atoms. This is an important factor in controled linear fisson (cutting from a distance):eek: ....anyway..if packing makes you feel like it's a better blade, by all means, do it. I wouldn't expect it to make any difference in the real world though.
 
Nick and Peter, Blacksmithing isnt science. Im going to send both of you a chicken foot to hang on the south side of your forges.
 
Thanks for telling me what I need, Bruce. I'll hang a chicken foot tomorrow!

"Packing" doesn't mean to actually pack the molecules closer. That would be physically impossible with the equipment the normal smith has. I think it means to refine the edge with a low heat, the way it's used by a lot of black smiths that I admire and respect.
My 2 cents, Lynn
 
Hey nick...if you were watching me at Ed`s, you`d have seen me do this very thing, I believe it helps, it was the way I learnt and is the way I still do it....you`ve seen the grain structure!! there is some magic involved....shhhhh!
 
I think Bill Moran does edge pack. I will watch his damascus video again and look for the chicken foot.
 
I was also taught that the reason there were presents on Christmas was because a fat man jumped down the chimney and brought them here. It must be true, because there were presents :p

I think that's one of the great things about knifemaking...if someone wants to do something because they believe it helps then that's fine. But the topic was a question on fact...so that's what I was looking to answer.

If someone is simply using the term "edge packing" as a way to describe their finishing hammer work, then that's fine I guess. However, it's misinformation as "historically" the term has been in reference to hammering the grain of the steel tighter, "breaking down the crystaline structure". This is a falacy as the grain refinement is due to proper thermal cycles, IMHO :)

Nick
 
well could this be a form of a cold forging? since it is done at a thermal temp? i wonder if mr.fowler has some thoughts on this pratice? or mr cliff stamp who may have comments about the grain struture. on a moleculer (sp?) level.
 
The hammering won't pack the steel any tighter, or refine the grain in and of itself, however the plastic deformation will raise the dislocation density in the steel which will act to induce an increase in grain refinement during the subsequent thermal processing because of the greater number of nucleation sites for the crystal transformations.

-Cliff
 
I think that Ed Fowler has shown us in all his great articles that forging bevels in a blade does SOMETHING GOOD to the steel as opposed to the same steel in a stock removal format.

I recall articles showing better cutting, grain structure, etc. on blades with the same heat treat, forged vs stock removal. So it looks like that just proper thermal treatments are just the only thing at play here.

Ed, if you are reading this thread, can you answer this? Have you found that forging in general, be it "edge packing" or just properly forging the bevels, creates a blade with a finer grain structure than a non forged blade? This, of course, with all things being equal in the heat treat.

Cliff's answer to this is very interesting and seems to help explain a few things about this process.

Greg Covington
 
I don't see the difference forging or edge packing
at lower heat, low heat forging is, They say, better than high heat anyway.
If this was not true and does not help, you have
a lot of testing to answer to And I think Ed will have something to say about it indeed...
testing gets results. and Ed's done a lot of it..
;)
 
Sorry to chime in late...

Edge packing has its merit when it is understood and the effect it has on various steels at various heats.

The topic, I feel, is actually quite exhausting. Not because it is pointless, but because it is not understood. There are a myriad of effects that alter each other and should be examined specifically. For example... I have some blacksmithing references to the technique. Some of it is true, most of it is not. The way the author presents it is incorrect, the actual effect is real (to an extent though). In his scenario it can be examined and determined as such. In the case of others, some are just flat out wrong. Others hit the nail on the head.

Something to keep in mind IMHO. Forging at low enough heat to be considered 'correct' edge packing, is still forging at low heat. There are specific consequences for doing such, just as forging at high heat. The skill of the smith is paramount. I also do not feel everything at the forge is meant to be studied in equal. Why? Because its all different. Getting a nice particular glowing color has its own set of learning challenges and understanding compared to squinting at the funny lines on an I-T diagram and judging in ones non-metallurgist mind whether or not such cooling speeds will create fine pearlite or some order of bainite. Plus, if you have to merge the two, you've just stepped into a whole new classroom!
 
It's like taking the word of a doctor on something he
has not seen for himself but going by what he heard from
another doctor or in text or school.
he could be right, only if the other doctor was right
the point is, if you do the testing yourself
you will know for sure.
 
Edge Packing -- I have a lot of theories, but can speak specifically to ne steel, 52100. If we forge at high temp, 1750 and above, there is little benefit to the steel as the grain grows with each heat, negating the most beneficial consequence of forging.

The more forging at low temp., 1625 f. maximum, the finer the potential grain size. We have reduced grain size by two points by purposfully concentrating as much forging activity in the area of the lower third of the edge, this is after forging down from a 5 1/2 inch round bar, about 98 point reduction by forging. Every hammer blow is of consequence to the steel. As us the temperature range it is forged through.

With the right steel, and proper plan, edge packing could be of some benefit, ie forging down through a black heat. This could approach cold forging, except it follows higher temperature forging. Smiths who forge at temperatures over 1700 may realize some benefit, but with 52100 steel you can get a lot further by working at lower temperatures all the way.

I have to go to work, will be back, any thoughts or questions will be addressed if you like. Thanks to the invite to this thread.
 
Ed, how are you determining the temparature at such a (relatively) close range so accurately?
 
You must log in or register to reply here.
Back
Top