high layer damascus cracking during forge?

Knifemaker87

Knifemaker87

Joined
Jan 2, 2006
Messages
1,073
hey everybody..
tried my hand at forging high layer damascus with some cable i had. i started with 6 fully welded strands with 36 strands a piece. those stacked on each other, welded and folded twice. well.. that was as much time as i had in the day (other stuff was going on.) but anyway.. the peice was MUCH MUCH smaller than it started out! why is that? and the billet cracked along the "corners" so they were cracks into the billet..
what did i do wrong.. and how can i fix it? i was fluxing with 20 mule team borax.. and fluxing very often.
thanks so much.
would pictures help? or is this a common problem?
thanks
~Chris
 
okay... i'll get some pics..
i actually ahve pictures of it in process.. and the first 6 were welded flat.. by pounding... they were welded fromt he cable by twisting.
i'll have pics up in a few...
 
understand I'm no exert on cable, in my limited experience with it twisting it gave me a much better weld. When it was just hammered I found voids on the inside during deep grinding. It might account for the "shinkage". Id have to see the cracks to hazard a guess.
 
Are you doing this by hand or with a power hammer? Were the cracks between strands or between billets? Forge gas or coal, and what temperature were you welding and drawing at? Did you cut open the billet and look at its insides?
 
If you look at the link it shows that he is using a gas forge and he is pounding this by hand.
 
I would say working the billet too cold. Make sure you are at welding heat any time the billet is worked heavily. Also soak time is very important to get a clean weld. I could not tell if your initial billets were ground clean or if they had scale on them. Clean works better though it can work if scale is left on them. Can't tell if it salvageable, are the crack only surface or do they go way into the billet?? If they are only a surface problem then it is possible but if they infiltrate the billet then start over and keep the heat up.

Chuck
 
I'd agree with Chuck that it may have been worked a bit cold. A few suggestions from my experience with cable (and damascus in general).

- Start by heating the cable to a dull red and fluxing, then get to an orange heat and twist as tight as you can. THEN weld.
- When welding, forge with the grain of the cable. Hard to describe, but try to "tighten" the twist of the cable with your hammer blows.
- LIGHT blows when welding cable. You don't have to (and shouldn't) smash the heck out of it when you're initially welding it up.
- Before re-stacking, grind all surfaces until they are clean and free of cracks. If you have a severe crack, re-heat, reflux, and reweld. This will save you from trouble down the road.
- Do all of your forging at a welding heat. You're going to have to normalize, etc to reset your grain structure anyways, don't wear yourself out and risk cracking steel by working at anything less than a full welding heat.

I cannot stress how important preparation work is in damascus making. Sure, you'll see guys who get good results and never grind scale off of anything, etc. You will see CONSISTANT good results from folks who take the extra time at the beginning of the process and keep everything clean and flat.

For what it's worth, it looks like you may have had some edge cracking in one of your six pieces that were re-stacked. Some of the detail shots of the billet show cracking that stops at weld boundaries. Also, if you were to "connect the dots" of some of the cracks they could be the diagonal remains of individual strands in the cable. Etch it and see if the cracks line up along the pattern.

All in all it's a very commendable first attempt. All the more impressive that you got that much work done by hand in a day. I look forward to seeing the continuation of your work.

-d
 
dekers comments are well said.

With cable, it is tempting to hammer away at it to "tighten it up". This creates the opposite effect. The strands loosen if hit hard. Gentle blows and constant turning until it is a solid bar. Then forge flat and fold. DO NOT FOLD until all strands are welded together. If it isn't welded before the fold, it probably will never get fully welded after the fold is made.
Stacy
 
I looked at your pics and dont see one that has a good welding heat. Are you sure you are hot enough? Lemon yellow is welding heat color. I use a pyrometer for consistant results.
 
I would agree with the comments about not enough heat. judging temperature by color is difficult especially when 'lemon yellow' is different for different people.Smiths usually work in reduced lighting so they can judge colors better.Even photos may not show color correctly.
 
ib2v4u said:
Please start wearing some safety glasses
Click to expand...

And please Chris FTLOG PLEASE raise that anvil up, I don;t mean to sound like an old dude but your back will thank you for it years down the road. Standard starting point for judging proper anvil height is stand straight up with your arms flat to your sides, then have a friend measure up from the ground to your knuckles of your hammer hand, and that should be the height of the face of the anvil. Preventive maintainence of the body is key to be hammering when you are 100 years old. There is all kinds of simple easy stands you can build no problem. Check out Adlai Stein's "City Boy Anvil Stump"


http://www.macabeeknives.com/articles/stump.html
 
hey..
thanks for the comments...
sorry i didnt see that i had any responses or i would have been back on to respond to some questions.

as for the original billet, after i welded the cable strands, i flattened them and ground the scale off before mig welding them so i could forge weld.

as for the cable thing... i know exactly what you are talking about.. i normally lightly hammer the very tip till it welds up (i do that first).. then i put that part in the vise (after heating again) and twist the crap out of it. that way ti doesnt distort or crimp the very tip of the cable where it was in the vise. then once it is all welded (i test to see if it welded by trying to twist it against the cable twist) i flatten it and go from there

with the peice i did... i havent etched it yet... going to.. had a slight accident with the acid.. and got sidetracked. btw.. getting it in your eyes WONT make you blind, but it is uncomfortable.. and it tastes nasty too... (thanks for the comment about the glasses.. just got some good ones.)

as for the billet, the cracks didnt start till after the first fold.. it was perfect till then. and i think you may be right about working it too cold.. but then there are no posted pictures of when it was really hot, and it was REALLY HOT. the flux was boiling on the surface of the steel, and i made sure to soak it good.

all the pictures are due to my lovly assistant (i told her i would tell yall that) normally i dont get many pictures of myself working. i am going to try it again, though maybe not with cable strands.. we will see.

well.. i am already at it again... forged up more cable from darren ellis. nothing fancy this time, just som cable damascus fior a stock removal knife. btw... all my flaws have always been in the very middle of the cable.. has anyone replaced that middle strand with sold steel? i thought about doing that but wanted to ask first.

also.. over on bladesmith's forums. they thought that it was possibly do to overheating.... do you think it could be some of both over heating and working too cold?
thanks yall!
~Chris
 
Sam Salvati said:
And please Chris FTLOG PLEASE raise that anvil up, I don;t mean to sound like an old dude but your back will thank you for it years down the road. Standard starting point for judging proper anvil height is stand straight up with your arms flat to your sides, then have a friend measure up from the ground to your knuckles of your hammer hand, and that should be the height of the face of the anvil. Preventive maintainence of the body is key to be hammering when you are 100 years old. There is all kinds of simple easy stands you can build no problem. Check out Adlai Stein's "City Boy Anvil Stump"


http://www.macabeeknives.com/articles/stump.html
Click to expand...


As an older dude with back problems who makes his living with his eyes who's got plenty of burn specks on some of my safety glasses as well as a t-shirt with a burn line right across the belly from my first forge weld flux spray (my wife bought me a leather apron when she saw the charred line on the shirt)

WEAR YOUR F'N SAFETY GLASSES

and as Sam said get your anvil up to the proper height. You need your eyes, and you don't want to be waking up at 40 with a bad back. I threw mine out when I was 20 working in a motorcycle shop, stacking bikes in the boneyard, also when your anvil is at the proper height you will be able to get the best power and control from your hammer, and it will seem effortless.


-Page
 
hey guys.. the face of my anvil is at about my knuckle height... is that what you are talking about? i mean if i have my hands at my sides,, the face is at about my knuckle height. should i still raise it up? thanks
~chris
 
why are you bending over when you are forging? the face of the anvil should be at knuckle height when you are standing next to the anvil, so if it is you're good, but the fact you were bending over while you were working, that was what indicated problem in pics,
BTW are you going to start wearing safety glasses? I hope they were just omitted for the pictures.

-Page
 
Knifemaker87 said:
hey guys.. the face of my anvil is at about my knuckle height... is that what you are talking about? i mean if i have my hands at my sides,, the face is at about my knuckle height. should i still raise it up? thanks
~chris
Click to expand...

If you find yourself still bending over alot even though it is at knuckleheight then yes try raising it a few inches and see if it keeps you from bending over so much. I tried working at kuckle height and have to consciously keep myself from bending, maybe it might be just a bit of correcting yourself until you do it without thinking. If you are having trouble seeing then maybe raise the anvil up.
 
Hey Chris,
Looks to me like the cracks are from overheating, or "red short". Some of my early billets had that. 1095 did it for me every time when I was starting out.

And I have to agree with everyone else; wear some safety glasses! :D I NEVER forge without them. And don't get the cheapy ones from the hardware store, get the good ones, like from Auralens. Eye transplants don't come cheap....

http://www.auralens.com
 
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