Sortening a Craked Bowie 1095

bobbywett

bobbywett

Joined
Jul 23, 2006
Messages
1,231
Hey folks, During heat treating of an 8" blade I noticed a crack close to the front of the blade and on the edge. The crack is approximately 1/2 an inch long. My blade material is 1095 High Carbon, is there a possibility of salvaging a smaller blade by shaping it to say 5 or 6" in length. All of mt fittings, (guard, pommel, and threaded tang are ready to go for this blade. I am currently tempering the blade at 425 degrees....will do this for an hour, let cool for 3 cycles. The blade was edge quenched.

Thanks,

Bob
 
1st off, sorry about the blade, that sucks. What was the quench medium?? If it was too severe there may be micro cracks in other parts of the blade that you can't see... Kind of risky to keep working with it... Hate to waste time fixing it up and find another crack later.. I say lock it in a vice and bend it till it breaks and try to learn something about the grain structure and what may have happened.. Crap I went over 1000 posts.... See what you made me do..:mad:;)
 
Louis, Checked out your website, really nice work. Thanks for you quick reply. My quench medium is a combo of 1/3rd each used motor/hydraulic oil, candle wax, and bacon grease...as per Wayne Goddard's $50.00 knife shop. I did normalize the blade 4 times by bringing it up to non-magnetic and holding it there for a minute or so each time. After each heat, I allowed it to cool in still air, at room temperature. I was wandering if the quick transport from my frigged garage (10 F. or so) to my 60 degree basement in between heat and cool cycles was the culprit. I did notice that the area that cracked appeared a brighter shade of orange than the rest of the blade right at quench time. The rest of the blade was uniformly orange, and just non-magnetic. The
quench-ant was heated to around 135 F. This has happened twice before, when it was cold outside. I've only done about 15 or so forged blades, all from 1095.....I heard 5160 is more forgiving.
 
Bob,
I would bite the bullet and make a new blade.There are probably several problems with that one. The existing hardware can be used on the new blade.
I would also suggest changing your steel to something that is deep hardening. 5160 would be a good choice for the quench type you listed (for God's sake, get some proper quench oil !!!)
1095 needs a bit more finesse, and has more risk than 5160.
It wasn't clear in your statement, but are you taking the blade from the forge in one room to another place to quench it?

Stacy
 
bladsmth said:
Bob... (for God's sake, get some proper quench oil !!!)...
Click to expand...

Stacy, you know if the right people read this we will end up with the exact same thread we had last week with the word "quenchant" substituted for "steel". To save the grief, I would suggest any actual quenchant! Let's at least start with a liquid, Wesson oil, ATF or hydraulic by itself, goats pee, virgins blood etc... as long as it can actually convect.

Watch your heat, there is no way 1095 should crack with any oil unless there was something seriously wrong going into the oil. Overheating at any point and then not correcting the grain size could do this. I have seen a lot of 1095 with a heavy segregation string running right down the center of the bar that needs to be broken up or it could results in cracking, but this cracking is usually lengthwise and not transverse. To break this up normalizing must start out hot! You may want to exceed 1800F at first and then work your way down, just be certain that you cooling is no slower than air.

As for the blade salvage, it is very important that you establish the cause or source of the crack to be certain that there are no other problems waiting to pop up in the remainder of the blade.
 
Thanks for responding to my post. From the feedback you folks provided and my e-mails to Karl Anderson, it appears I made more than one mistake on this blade. Heat was probably too hot before quench, heat was not uniform over entire edge of blade, blade edge was most likely too thin at time of quench, and quench was wrong solution. When the blade was quenched, edge first, one area, the area that cracked appeared to be hotter/brighter than the rest of edge. My forge needs refractory repair on the roof where nozzles emanate. I thinks cracking in this area provides poor heat control. I also thick that waiting for the blades entire core, instead of just the edge to go non-magnetic was a mistake? What do you folks think?

Stacy, I currently have my quench source right beside my forge (3 adjustable burner, propane). I can take blade from the forge directly to the quench, which I heat to around 120F. to 130F in an old 18 quart electric roaster. I also gauge quench temperature by use of a candy makers thermometer. I do, however, take the blade inside my basement, in between, normalizing cycles and to temper after quench. I temper in a store bought toaster oven.

I've checked out other posts for both of your profiles and past work (really nice stuff). I'm fairly new to this and greatly appreciate any and all advise.
 
I would like to add another question. Where are you putting the blade while it normalizes? I had the same problem when I started out, my mistake was setting the blade on the anvil while letting it cool. I made the choise to spray paint it and keep it as a pattern/ reminder of were I started.
 
I've been standing them in a simple rack made of a 2 X 4 with wood screws for standing them edge down. I usually let them cool indoors during the colder months, my garage gets pretty darn frigged. I've had three out of around 18 crack, and I think from the info I'm getting back on the forum, I've overheated those that cracked.

It sucks when then crack, but theirs always another day to forge one up. And ya gotta learn some how, right. I'm probably gonna incorporate some new quench oil and practice on some 5160 instead of the 1095 for now.
 
Hey guys, don't any of you smithies use pure olive oil for quenching anymore?
I thought it was supposed to be a good quenchant and made the shop smell like a bakery! :D
 
I use olive oil at 130f because I haven't spent the money yet on proper quenchant, it is not fast enough for 1095 over 3/16th inch which is why I currently do not use 1095 with a final size that is thicker than that, The crack pattern reminds me of what one of my students got , near as I can tell by continuing to try to move metal on his blade when it was too cold (his blade was 1084)
also try vermiculite or wood ash for letting your blade cool, failing that, turn off your forge and leave the blade inside.

just a thought. experiment and see what works before wasting huge effort again.

-Page

Oh yes, either get slower steel or faster quenchant, 1095 and Goddards Goop are not a good combination.
 
Now that you mention it, my steel was 3/16th inch at start of forging process and not much thinner at the spine when quench time rolled around. On this knife I hot forged to rough shape and cold forged a bit to refine the bevels and the distal taper (to lazy to fire up the forge). Instead of using belts to remove stock, (out of them right now) I used large 2nd cut files to remove remaining stock. I finished to 320 grit on the bevels and flats and then shaped the too thin edge (penny thickness at ricaso, tapering to small paper clip thickness near the point) with a mere 60 grit.

I have heat treated acceptable blades (handful in my overall experience, all 1095) successfully with Wayne Goddard's recommended goop, however, I now know that was one of mistakes. With the available commercial grade quenches, I can look forward to reducing one variable in my quench success ratio. I'm not a rich fellow, but I will take the money, time, and effort to invest in some commercial grade quench. What I'm learning from the fine folks on these forums and through direct communications with individual knife makers is I'll likely be purchasing a fast and medium quench. I'd like to learn to work with all the 10 series and 5160, W1 and W2 steels (not even close to working with Damascus yet).

I'm guessing with the appropriate set up of quenches, I'll be spending anywhere from $80 to $150 bucks for the 2 speeds. But, if you think about it this way, I spend that much every couple of months on grinding belts. And those belts aren't even going to last 1/10th as long as the quench.....which could last years....from what I'm-a-learning.

Page, I do have a 5 gal bucket filled with vermiculite, which I sometimes anneal blades in overnight. I am currently placing blades vertically, point down in the medium. Should I consider placing the vermiculite in a shallow pan, and placing the blades in, horizontally, edge down, edge up?

Thanks For Any Thoughts.
 
bobbywett said:
............ On this knife I hot forged to rough shape and cold forged a bit to refine the bevels and the distal taper (to lazy to fire up the forge).

Thanks For Any Thoughts.
Click to expand...


I'm a little concerned about that second sentance! Especially the "cold forged" part?
According to the heat treater's handbook, or whatever the name of it is:
"Heat to 2100 F. Do not forge below 1500 F."
That, in conjunction with the 60 grit scratches on the "too thin edge" can only result in disaster.
 
Several things here. I believe Karl is really onto something. If the cracking is indeed transverse and not lengthwise then it becomes very difficult to blame this on something inherent in the steel. Two huge red flags pop up with more discussion. The vermiculite treatment from above non-magnetic is a big no-no with steels that have .9% Carbon or above, I know many smiths for years have said otherwise and I am here to say that they are just dead wrong! This is not something I think, this is something I know from years of testing it and looking at it under the microscope. But the "cold forging" thing is the biggest red flag, I would put it at 60% likely that is when your cracks were formed. Regardless of what you may have read or heard anywhere this sort of problem is what you can expect when you hammer high carbon steel cold. These are the sort of things that makes experienced knifemakers grit their teeth and force themselves to be nice when their advice is met with "But I read...” or "That famous guy said...". So much good information has been given out over the years, but along with have been a few bits of pure tripe that has caused more problems than they have helped with new makers. Absolutely absurd quenchant alternatives (I am not talking non commercial stuff, I am talking about ideas that make ATF look like parks #50!), totally improper forging temperatures, and heat treating ideas that are more problematic than helpful are at the top of that list. Bobbywett you and your blade are the latest victims of this information. People often ask about or comment upon my willingness to post information in these forums, my main motivation is to undo some of the damage that ahs been done by other well meaning yet very mistaken bladesmiths who have been given unquestioned authority in areas that they obviously needed more in-depth information on.
 
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I feel that correct information, no matter how long it takes to come by it, is worth the mistakes it takes, and drive it takes to acquire it. I don't feel like a victim, I'm just paying my dues. Worse things have happened to better people on nicer days. I've taken to learning the craft, skills, and techniques because I have a deep interest in the art.

Mistakes will be made, overcoming them, with help from those such as yourself and others will only make me a better bladesmith. And if I can help others as I go, and in the future, then thats what I'll do.

Sure its depressing to have a blade crack, especially after putting in all the time, but to me its worth the effort.
 
Kevin, thank you for the info about the vermiculite cooling.
what do you reccommend in its place?
-Page
 
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