Twist Damascus FAIL

[JTknives]

Well i Finley got the balls to do some Damascus after all these years. and the funny thing is that i did do Damascus years ago and had no problems, i was not doing any twisting. but well today was different. I started with 1095 and 15n20. the 1095 was a bit thinner then the 15n20 so i doubled it up and made a stack of 16 layers like such.
C=1095 N=15n20
NCCNCCNCCNCCNCCN

first weld went great, i wired the ends and set the forge to 2300. stuck the steel in and let it warm up a bit. pulled it out and gave it a bath of borax. then back in and let it come up to temp. then one more sprinkle of borax then back in. then out it came and into my press. i pressed the middle first as the ends had wire. so i gave it one good squish. then cut off the wire and fluxed the end. i then pressed the ends. i then cut it in 2 and ground both surfaces and wired them together. i did notice that the ends had some cold shuts but the middle was fine. so i kept repeating this process a total of three times. on the last time i welded them together. then turned it edge up and squished it down square and it held great. i rounded it a bit with the press. then back into the forge and then i clamped one end in the press and twisted the end. i could not get it twisted as much as i wanted on the first heat so i reheated and re twisted. after i wire brushed off all the flux i saw a gaping weld shear, or cold shut that oppend. I was wanting to twist it more but once i saw this i stoped. it was the weld that i had just done and it held just fine with the vertical press so i thought it was great. but i guess not. i will post a picture so you can see my failure. man i was bumbed, 6 hrs and a tank of LP went into this. i guess its a learning experance but thats onley if i can find out what i did and fix it next time. Any ideas? o ya and in the pictures it looks flat and it is, i flaghtened it after i saw the fail so i gould grind the surface and see maybe what happend.

 

[delbert ealy]

Well i Finley got the balls to do some Damascus after all these years. and the funny thing is that i did do Damascus years ago and had no problems, i was not doing any twisting. but well today was different. I started with 1095 and 15n20. the 1095 was a bit thinner then the 15n20 so i doubled it up and made a stack of 16 layers like such.
C=1095 N=15n20
NCCNCCNCCNCCNCCN

first weld went great, i wired the ends and set the forge to 2300. stuck the steel in and let it warm up a bit. pulled it out and gave it a bath of borax. then back in and let it come up to temp. then one more sprinkle of borax then back in. then out it came and into my press. i pressed the middle first as the ends had wire. so i gave it one good squish. then cut off the wire and fluxed the end. i then pressed the ends.Here is where you screwed the pooch, you should have welded the whole thing right away, with the size of the billet and the time to cut the wire the billet was not at welding temp. i then cut it in 2 and ground both surfaces and wired them together.to me it sounds like this billet could have used a bit more time in the fire. i did notice that the ends had some cold shuts but the middle was fine. so i kept repeating this process a total of three times. on the last time i welded them together. then turned it edge up and squished it down square and it held great. i rounded it a bit with the press.Here is another place for the source of the fubar, if our last weld was not quite sound, you could have split it right here, in fact looking at your piece I think this is most likely. then back into the forge and then i clamped one end in the press and twisted the end. i could not get it twisted as much as i wanted on the first heat so i reheated and re twisted. after i wire brushed off all the flux i saw a gaping weld shear, or cold shut that oppend. I was wanting to twist it more but once i saw this i stoped. it was the weld that i had just done and it held just fine with the vertical press so i thought it was great. but i guess not. i will post a picture so you can see my failure. man i was bumbed, 6 hrs and a tank of LP went into this. i guess its a learning experance but thats onley if i can find out what i did and fix it next time. Any ideas? o ya and in the pictures it looks flat and it is, i flaghtened it after i saw the fail so i gould grind the surface and see maybe what happend.

JT,
Don't give up, it will get better. One question though, why did you wire it instead of arc welding it? Welding it and adding a handle helps.
If you run into more trouble give me a call and we can talk it out.
Del

 

[deker]

Jarod,

It actually looks mostly good. Don't stress too much, it takes a little doing to get this stuff right. Twists in particular can be a bit of trouble until you get them down...and even after, change one thing and they can go to crap on you in a heartbeat.

Take Delbert up on his offer, you'll be glad you did for many reasons.

-d

 

[Stacy E. Apelt - Bladesmith]

With twist ( really, with any damascus) the welds need to be right the first time. You can't beat a weld into a billet over several heats, and expect it to hold up during manipulation.
Secondly, a twist billet needs to be more than, "Rounded up a bit". It needs all the corners gone. If it isn't at least a rounded octagon ( far better is nearly round), the corners will tear upon twisting. Even on a perfectly welded billet, you will have to grind off the "corkscrew" if you don't pre-forge to round, so save some time and heartache by making it round before twisting.

Note to those who are considering trying a twist billet - Never try and forge the corkscrew back into the bar. It will ruin it by filling it with bad spots. Once the billet is twisted, grind it to a smooth surface before forging to a flat bar. I know there are exceptions to this with folks who do a lot of damascus, but for those starting out, it is the rule to use.

Stacy

 

[69_knives]

W man i was bumbed, 6 hrs and a tank of LP went into this.

Hey JT,

Don't wanna HJ your thread but I'm going to take some pics of my oil burner setup and post them up. I know (I think) you were interested in using oil as fuel so I'm sure it will be of some use. It worked unbelievably well yesterday; 2200°F +. My setup is sort of limited by the small blower setup so it's pretty well maxed out at that temp but I think if I rework my coffee can blower it would get hotter if I wanted. I'm just scared to mess with it now as it's working so well.

Also, it's based off of this exact burner Basically just imagine that burner with the 1/4" copper tub coming from the oil tank carefully winding around the 3/4" burner tube 2 times and then a hole drilled in the top of the 3/4" burner tube just behind the flare. drop the 1/4" oil tube in that hole about 3/8".

I keep reading that a blown burner requires at least a 1.5" burner tube but my setup proves that this is not correct. I'll post a new thread on the burner setup tonight (hopefully)... it may be late.

 

[JTknives]

JT,
Don't give up, it will get better. One question though, why did you wire it instead of arc welding it? Welding it and adding a handle helps.
If you run into more trouble give me a call and we can talk it out.
Del

I would have welded it but our welder was sick and had to go to the doctor. its a nice welder all digital and everything but the power switch failed and would not turn it on so we had it fixed. thy say next week some time we will get it back. thy have had it for 2 weeks already .

was i wrong to press the middle first and then do the ends? this is very exciting as its new ground and will be fun to experiment.

 

[delbert ealy]

I would have welded it but our welder was sick and had to go to the doctor. its a nice welder all digital and everything but the power switch failed and would not turn it on so we had it fixed. thy say next week some time we will get it back. thy have had it for 2 weeks already .

was i wrong to press the middle first and then do the ends? this is very exciting as its new ground and will be fun to experiment.

JT,
When I weld a billet I usually hit it in 3 squeezes too, starting at one end, then the middle then the other end, in about 6 seconds for the whole operation. The steel cools off a lot quicker than you might think.
Also, when you knock the corners off the square bar, do it at welding heat.
Del

 

[JTknives]

JT,
When I weld a billet I usually hit it in 3 squeezes too, starting at one end, then the middle then the other end, in about 6 seconds for the whole operation. The steel cools off a lot quicker than you might think.
Also, when you knock the corners off the square bar, do it at welding heat.
Del

do you round over the tops of the steel layers befor stacking or just grind them flat.

 

[Fred.Rowe]

Forging the billet into a square shaped rod, at forging temp, after the initial weld is complete is a good start. After this step, shaping the square bar into a round rod before twisting results in the most usable material. Work a small section of the bar at a time until it is fully rounded.



Try it with a section of clay and take a look at the result.

I know most of this is stated above; I just wanted to reinforce what was said.

Fred

Has anyone out there made a die for your press that will turn a square bar into a rounded one? I have considered it but have not had the time to produce one.

 

[delbert ealy]

do you round over the tops of the steel layers befor stacking or just grind them flat.

I just stack them flat, I always thought that convexing proir to stacking was far too much work for far too little gain. Although with some of the ways I stack steel I really shouldn't comment about such matters.

Fred, I am working on a die for my rolling mill that makes octogons out of squares and then the octogons into rounds. I'll post some pics when I get it done.
Del

 

[JTknives]

JT,
Don't give up, it will get better. One question though, why did you wire it instead of arc welding it? Welding it and adding a handle helps.
If you run into more trouble give me a call and we can talk it out.
Del

I might take you up on this next time if its ok. i might do another try on monday as i cant stop thinking about it . propane is cheap and i have the steel.

 

[Stacy E. Apelt - Bladesmith]

Has anyone out there made a die for your press that will turn a square bar into a rounded one? I have considered it but have not had the time to produce one.

I'm not sure what you mean ,Fred. Doesn't everyone have a set of rounding dies?
If you don't, make yourself a set. Simplest way it to bore a 1" hole ( or the desired size) in a block and cut the block in half on the bandsaw. Weld each half to a die plate.Voilà, a set of round dies. Use the dies to grip the billet when twisting,too.
When the billet is ready to round out, press the corners into an octagon on the flat dies. After rounding the corners fairly well, switch to two round dies ( Mine are 1"). Press the billet to a complete round rod. It will twist very nicely after that, The plus is that there is little chance of a bad weld if all the pressing is done at welding heat ( or near it).

If hand rounding a billet, do it at full welding heat. Compressing the corners back into the billet will shear any bad weld if you don't.
Stacy

 

[delbert ealy]

I might take you up on this next time if its ok. i might do another try on monday as i cant stop thinking about it . propane is cheap and i have the steel.

JT,
The offer is open, I have forging work everyday for the next 3-4 weeks.
And I know how this can be absorbing, I have a week to finish the order I am working on and then I have a bunch of steel to make for inventory, I make more than 20 patterns and I plan to make at least 2 new patterns in addition.
I haope to get most of those patterns done and that means doing a different pattern every day for at least 2 weeks, I have been waiting for 2 years to do this and I am excited. I also have a challenge, I have some meteorite damascus to do, and I havn't made any in 3 years. Meteorite damascus is The most difficult thing I have done, period. Sorry for rambling, send me your # and I'll talk your ear off about damascus.
Del

 

[Fred.Rowe]

I just stack them flat, I always thought that convexing proir to stacking was far too much work for far too little gain. Although with some of the ways I stack steel I really shouldn't comment about such matters.

Fred, I am working on a die for my rolling mill that makes octogons out of squares and then the octogons into rounds. I'll post some pics when I get it done.
Del

I will keep an eye out for your post. I like time saving jigs and devises. Fred

I'm not sure what you mean ,Fred. Doesn't everyone have a set of rounding dies?
If you don't, make yourself a set. Simplest way it to bore a 1" hole ( or the desired size) in a block and cut the block in half on the bandsaw. Weld each half to a die plate.Voilà, a set of round dies. Use the dies to grip the billet when twisting,too.
When the billet is ready to round out, press the corners into an octagon on the flat dies. After rounding the corners fairly well, switch to two round dies ( Mine are 1"). Press the billet to a complete round rod. It will twist very nicely after that, The plus is that there is little chance of a bad weld if all the pressing is done at welding heat ( or near it).Stacy

That makes since, Stacy. Did you round over the corners on your rounding dies or leave them as they were when you cut the block in half?
What steel did you use to make your rounding dies?

To many projects; not enough time. Fred

 

[Fred.Rowe]

If hand rounding a billet, do it at full welding heat. Compressing the corners back into the billet will shear any bad weld if you don't.
Stacy

Stacy,

Elaborate on this statement.

If you have made good welds in the flat stage of the billet, does it not make sense to do the rounding over of the edges at forging heat instead of welding heat so as not to de laminate already good welds?

Thanks, Fred

 

[Stacy E. Apelt - Bladesmith]

Fred,
If the welds are good, it may not matter, but there is a boundary at all of the larers, so any stria can be the point of a split....even if the welds are good. If using a press, the pressure is even, so splitting good welds is less likely. If hand rounding, the pressure is much more localized. Doing it at welding heat ( or near it) will allow the layers to reorient without shearing. Any that try to open will most likely weld shut at the same time. At a lower temperature the core may be colder than the corners, causing the weld to smush open on the edge.

Stacy

 

[Fred.Rowe]

Fred,
If the welds are good, it may not matter, but there is a boundary at all of the larers, so any stria can be the point of a split....even if the welds are good. If using a press, the pressure is even, so splitting good welds is less likely. If hand rounding, the pressure is much more localized. Doing it at welding heat ( or near it) will allow the layers to reorient without shearing. Any that try to open will most likely weld shut at the same time. At a lower temperature the core may be colder than the corners, causing the weld to smush open on the edge.

Stacy

Thank you for making your reasoning more clear. That makes sense.
I run the temperature hot enough to where the steel moves easily under the hammer while trying to round it into the shape wanted for twisting. That is around 2150 or so.

I use a big rosebud, on the O/A system, when doing a really tight twist, clamping one end in a vise, while having an octagon bar welded too the other end; with a big ratchet that fits on it. I do this at welding temperature and sprinkle a little anhydrous on while making the twist. I find this works to produce a very tight unblemished pattern.
Doing this operation with two people, one on the torch and one on the ratchet, gives a lot of control over the final pattern.

Do you like the tighter twist or the more loose ones?

Fred

 

[delbert ealy]

Fred,
I gave up twisting by hand a few years ago, and I built a twister.
I got thinking about this after both my father and one of my friends had shoulder surgery. Twisting is one of those things that is hard on my shoulders. With the amount of the twisting I do its a good thing. I have 55 one foot bars one inch square tomorrow. I don't have a torch, but I get good even heat on the stock and run it. Mine runs at 8rpm. I woudn't mind a bit faster, But I don't want to decrease the torque.
Del

Btw, are you going to caimbridge this year?

 

[Stacy E. Apelt - Bladesmith]

I'm a fan of tight twists. They look better ( have a higher layer count) and can be used to create other patterns with less alignment problems.

To explain that statement better, imagine trying to align up a left and a right twist for a composite bar. If the twist is 5 turns per inch, any misalignment will show clearly. If it is 20 turns per inch, there will seem to be a perfect alignment all the way down the billet.

A great billet for a dagger is to take a left and a right twist about 6" long and 1/2" square, and two 6"X1/4X1/2" bars of 1084. Stack them 1084/left/right/1084. Tack together and weld up. Clean up the billet on the grinder,and draw it out into a bar 12" long, 1/4" thick, and tapering from 1" to 1.25" wide.... with the billet having the 1084 on the sides. This will give you a bar of steel with a tight herringbone center and mono-steel edges. Cut a curved "V" into the 1" end so it looks a fish tail. It should go 1" up the center of the twists. Forge weld the "V" closed, creating a rounded tip. (you can practice this on a piece of plain steel to see how the tip looks before risking the composite billet. Draw the other end into the tang . Forge out the bevels carefully and you will have a superb Viking look dagger - or make this a little longer and wider for a short sword.
Stacy

 

[Fred.Rowe]

Fred,
I gave up twisting by hand a few years ago, and I built a twister.
I got thinking about this after both my father and one of my friends had shoulder surgery. Twisting is one of those things that is hard on my shoulders. With the amount of the twisting I do its a good thing. I have 55 one foot bars one inch square tomorrow. I don't have a torch, but I get good even heat on the stock and run it. Mine runs at 8rpm. I woudn't mind a bit faster, But I don't want to decrease the torque.
Del

Btw, are you going to caimbridge this year?

Yes I will. There are a couple of guys that have apprenticed at my shop that will be setting up either side of me. It is their first show.

I hope to see you there.

Fred

I'm a fan of tight twists. They look better ( have a higher layer count) and can be used to create other patterns with less alignment problems.

To explain that statement better, imagine trying to align up a left and a right twist for a composite bar. If the twist is 5 turns per inch, any misalignment will show clearly. If it is 20 turns per inch, there will seem to be a perfect alignment all the way down the billet.

A great billet for a dagger is to take a left and a right twist about 6" long and 1/2" square, and two 6"X1/4X1/2" bars of 1084. Stack them 1084/left/right/1084. Tack together and weld up. Clean up the billet on the grinder,and draw it out into a bar 12" long, 1/4" thick, and tapering from 1" to 1.25" wide.... with the billet having the 1084 on the sides. This will give you a bar of steel with a tight herringbone center and mono-steel edges. Cut a curved "V" into the 1" end so it looks a fish tail. It should go 1" up the center of the twists. Forge weld the "V" closed, creating a rounded tip. (you can practice this on a piece of plain steel to see how the tip looks before risking the composite billet. Draw the other end into the tang . Forge out the bevels carefully and you will have a superb Viking look dagger - or make this a little longer and wider for a short sword.
Stacy

That sounds like an interesting technique. I have never tried the end cut like you are talking about. I,ll give that a try.

Fred