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View Full Version : Making Mosaic type Damascus for thin blades.



WillC
07-30-2011, 12:53 PM
Here is my quandry. I would like to start making W's pattern style mascus for thin blades. I'm not keen on the idea of loosing loads of stock cutting to expose the pattern. So I tend to compress my W's, then do the final stack to 6 or 8 and forge it out so the W's decompress and are on the top and bottom of the billet in the end. Trouble is getting the compression right. I seem to have it fine for 5mm blades, but forging down to 2mm and below is a different matter. Next I want to try this pattern, but forge it down to an inch square, cut it in half lengthways. Cut the halfs so I have 4 pieces for a 4 bar pattern. Then try forging into a thin wide billet for Santoku. Hopefully I will still have some W's left.
Does any one else have these kind of issues with more complex patterns and thin forged blades. Or do you have a few tricks up your sleeve?

jmforge
07-30-2011, 01:14 PM
If the pattern is an end grain one that goes all the way through the billet as opposed to being a twist based pattern like firestorm or explosion where you have to grind away 2/3 of the steel to expose the pattern, why not make a thick billet to the width that you need and maybe even the rough blade shape, square the flats and surface grind it and then cut it or have it cut on an EDM machine into say 3/16 slices lengthwise and surface grind it down to the desired thickness? Kind of like a "loaf" billet.I would think that would be a good argument for doing a "Ferry flip"as opposed to an accordion cut as the pattern on the final thin bars would be pretty much lined up from one side to the other and you wouldn't have to waste half of the final billet accordion cutting it.
Here is my quandry. I would like to start making W's pattern style mascus for thin blades. I'm not keen on the idea of loosing loads of stock cutting to expose the pattern. So I tend to compress my W's, then do the final stack to 6 or 8 and forge it out so the W's decompress and are on the top and bottom of the billet in the end. Trouble is getting the compression right. I seem to have it fine for 5mm blades, but forging down to 2mm and below is a different matter. Next I want to try this pattern, but forge it down to an inch square, cut it in half lengthways. Cut the halfs so I have 4 pieces for a 4 bar pattern. Then try forging into a thin wide billet for Santoku. Hopefully I will still have some W's left.
Does any one else have these kind of issues with more complex patterns and thin forged blades. Or do you have a few tricks up your sleeve?

WillC
07-30-2011, 01:29 PM
Thats a good plan. I could do a big loaf and just keep it in the end grain. Maybe several W's billets combined into the final loaf, 100mm x 50mm by however long I can do. Forging them out a bit does no harm if they are a bit compressed. So i could just cut 5mm slices to forge out to the right size. Need to get the donkey saw going though. I might start with a twisted W's type and do the cut down the middle. Lots of experimenting to do. I've not tried the firestorm yet.

jmforge
07-30-2011, 02:08 PM
I haven't tried firestorm yet, but from what I see, you end up with 1/3 blade steel and 2/3 waste if you saw the middle out. The side pieces could be used for bolsters or cladding for a san mail blade, but you wouldn't want to grind into them too deeply or you would lose the pattern and be stuck with the plain twist from the outside of the original bar. Tiling would eliminate that problem, but it dosn't really help you on those twist based W patterns. Now if you wanted to do something like that high contrast 4 way radial starburst pattern that Mick Maxen showed on his BB tutorial and tile that out.........:D Kyle Royer did a pattrn like that that didn't use the dark filler steel and he 4 wayed it one or two more times to get a lot of those little brusts and then tiled it using the Ferry method. He has a number of tutorial/WIP videos on his website and on Youtube.
Thats a good plan. I could do a big loaf and just keep it in the end grain. Maybe several W's billets combined into the final loaf, 100mm x 50mm by however long I can do. Forging them out a bit does no harm if they are a bit compressed. So i could just cut 5mm slices to forge out to the right size. Need to get the donkey saw going though. I might start with a twisted W's type and do the cut down the middle. Lots of experimenting to do. I've not tried the firestorm yet.

WillC
07-30-2011, 02:13 PM
Now that could be a plan. I've been meaning to have a crack at that one. Spare days is all I need...:wink:

JMJones
07-30-2011, 02:55 PM
I have made some attempts to get a mosaic pattern on something as large as a chef knife and to be able to get a few knives out of the pattern. I got a quote for having an EDM cut the loaf and it was about 150 dollars per slice. That is pretty pricey. I believe a large metal cutting bandsaw with a sturdy fence would be the way to go. Also for some reason for me and in my shop, getting a very solid weld when you are stacking all the w's billets is very very difficult. I have two pieces of damascus that have totally kicked my ass. It totally can be done it just a matter of working out the process that will work. Best of luck, I would love to see some progress shots.

WillC
07-30-2011, 03:11 PM
I think I'm gona go for some controlled distortion until I get my big saw fixed. I've been making 30 layer W's billets and compressing them, then forging out with the pattern on top. I think with a 30 layer start the W's are getting too fine. I quite like a bit of distortion so i'll try this to start with with a bolder start billet. Could always just forge it to inch square and slit it lengthways. Then I would have 2 billets of W's I can forge out a bit more without things getting lost. Really want to give Micks one a go though. There is picture of a "fire within " Billet somewhere he accordian cut. Wasteful but it looked amazing.:D

jmforge
07-30-2011, 08:15 PM
From what I have been told, you should dry weld tiles. Some guys use a can or foil and others weld all of the seams. I am told that the cleanest method is to use a TIG torch and seal up the seam without using any filler metal. I have also heard that folks will super glue the tiles together first and the glue burns up any oxygen that might be trapped when you put it in the forge. Doing it the normal way with borax supposedly can be tougher and leave you with gray lines. As for the EDM, they must be charging a hell of a lot for setup Bailey Bradshaw and Steve Scharzer both have EDM setups. Steve used to offer EDM services to knifemakers (don't know if he still does) and I don't think any of them could afford $150 for one cut. he implied that you could pretty much offset the cost based on the amount of metal you didn't have to waste cutting it with a saw.
I have made some attempts to get a mosaic pattern on something as large as a chef knife and to be able to get a few knives out of the pattern. I got a quote for having an EDM cut the loaf and it was about 150 dollars per slice. That is pretty pricey. I believe a large metal cutting bandsaw with a sturdy fence would be the way to go. Also for some reason for me and in my shop, getting a very solid weld when you are stacking all the w's billets is very very difficult. I have two pieces of damascus that have totally kicked my ass. It totally can be done it just a matter of working out the process that will work. Best of luck, I would love to see some progress shots.

jmforge
07-30-2011, 08:20 PM
I didn't like the way that Mick's billet looked when he accordion cut it. The round outside tops of the cuts messed with the pattern too much. That is a pattern that needs to be tiled or at a minimum, use the drill and cut at 45 degree methoed, but thayt would waste even more..
I think I'm gona go for some controlled distortion until I get my big saw fixed. I've been making 30 layer W's billets and compressing them, then forging out with the pattern on top. I think with a 30 layer start the W's are getting too fine. I quite like a bit of distortion so i'll try this to start with with a bolder start billet. Could always just forge it to inch square and slit it lengthways. Then I would have 2 billets of W's I can forge out a bit more without things getting lost. Really want to give Micks one a go though. There is picture of a "fire within " Billet somewhere he accordian cut. Wasteful but it looked amazing.:D

Marko Tsourkan
07-31-2011, 12:12 AM
The process you are listing here is a bit too technical for me, but I would like to comment about thickness. An idea that kitchen knives have to be super thin (2mm and under, unless you are factoring in a distal taper and measuring near the tip) is overrated. Proper grind on a thicker knife will give you a better performance than so called "lasers" and you will get a heft and rigidity. I would not make a knife thinner than 1/8 over the heel (in finished state), as you will get flexing and a flimsy feel - a sign of an inferior knife in my opinion.

M

jmforge
07-31-2011, 12:55 AM
Getting any stock even down to 1/8 with anything other than a power hammer or rolling mill is a pain. that is not an issue if you are buying thin monosteel, but if you are making damascus, you would need to get it down to at least 3/16 and then surface grind it. I have a 20 ton press and it doesn't like to go much below 3-8 to 1/2 on wide stock with the dies that I have now. You end up with a lot of scale on the floor when you go thinner. I am getting a 25 pound Little Giant up and running and that will help, particularly with widening stuff out, but if I had LOTS of money, I would buy a bigger press, like 50 tons, a rolling mill and a Say Mak power hammer tomorrow!!!
The process you are listing here is a bit too technical for me, but I would like to comment about thickness. An idea that kitchen knives have to be super thin (2mm and under, unless you are factoring in a distal taper and measuring near the tip) is overrated. Proper grind on a thicker knife will give you a better performance than so called "lasers" and you will get a heft and rigidity. I would not make a knife thinner than 1/8 over the heel (in finished state), as you will get flexing and a flimsy feel - a sign of an inferior knife in my opinion.

M

WillC
07-31-2011, 04:11 AM
The process you are listing here is a bit too technical for me, but I would like to comment about thickness. An idea that kitchen knives have to be super thin (2mm and under, unless you are factoring in a distal taper and measuring near the tip) is overrated. Proper grind on a thicker knife will give you a better performance than so called "lasers" and you will get a heft and rigidity. I would not make a knife thinner than 1/8 over the heel (in finished state), as you will get flexing and a flimsy feel - a sign of an inferior knife in my opinion.

M
Thanks yeah, I guess i'm going a bit thin for your tastes. I'm forging my damascus blades to about 2.5mm over the heel. I forge a bit of the taper in to so it tapers to say 1.8mm on the spine. After I have cleaned them all off they are just a tad over 2mm on the spine. That is for a little Petty, don't you think a Petty should be thin? I follow what your saying about the grind, because you can still have a thin knife which has too much metal behind the edge. I've not made any Kitchen knives bigger than 200mm or so so have not had any flex issues. Also the Santoku are quite deep with not much distal taper. I Can see the flex becoming a problem on the long thin ones so i'll bear that in mind. Generally I'm making what the customer specifies When they know what they like. If its for me... Well I haven't got round to making any to keep but I test all of what I make, including a Seax I made recently, which at 6mm on the spine and a grind like an axe... I have to say doesn't make a great Kitchen tool:D

WillC
07-31-2011, 04:23 AM
Getting any stock even down to 1/8 with anything other than a power hammer or rolling mill is a pain. that is not an issue if you are buying thin monosteel, but if you are making damascus, you would need to get it down to at least 3/16 and then surface grind it. I have a 20 ton press and it doesn't like to go much below 3-8 to 1/2 on wide stock with the dies that I have now. You end up with a lot of scale on the floor when you go thinner. I am getting a 25 pound Little Giant up and running and that will help, particularly with widening stuff out, but if I had LOTS of money, I would buy a bigger press, like 50 tons, a rolling mill and a Say Mak power hammer tomorrow!!!
Presses are useless on thin material and red finishing heats. Even at 50 ton they just suck the heat. I just use mine to keep everything flat at this point. Hammer is king for me. Flatting my dies a bit has made things a bit easier. After nearly 10 years of forging tapers I was getting a ridge down the centre of my knives if I was not careful before.:eek2: I use a little Anyang 40K and they do allot for their size. I've always wanted a big Massey, until I found out how much they can cost to install:scared4:

Marko Tsourkan
07-31-2011, 01:16 PM
Even on petty I prefer thickness be over 2mm over the heel but I could live with 2mm. Knifes I would use 1/8+ over the heel would be 8-10" range.

M

jmforge
08-03-2011, 12:39 AM
I waste a lot of steel I guess because I am not capable of forging to 90-95% of finished size. I guess the upside of doing the old "forge thick and grind thin" thing is that is doesn't take two sharpenings to get to the hard steel on my blades.:wink: Any power hammer is good to have. I have asked a number of guys what they would want if they could only have one Little Giant and most said a 50 pounder. I would want a BIG press because you can squish a full stack when doing the initial welding of damascus using a full length set of flat dies, so no shearing of the welds and fanning out the layers on one end when you press the other end like what can happen if you get too aggressive with drawing dies. I actually have a set of beveling dies on my press. They are too wide to really bevel effectively, but they are fantastic for finishing heats because the straighten the edge right out.
Presses are useless on thin material and red finishing heats. Even at 50 ton they just suck the heat. I just use mine to keep everything flat at this point. Hammer is king for me. Flatting my dies a bit has made things a bit easier. After nearly 10 years of forging tapers I was getting a ridge down the centre of my knives if I was not careful before.:eek2: I use a little Anyang 40K and they do allot for their size. I've always wanted a big Massey, until I found out how much they can cost to install:scared4:

WillC
08-03-2011, 03:52 AM
I've been veering away from using my vertical press for the first weld. But I have to be super careful with the thin 1mm bandsaw stock i'm using not to get any nastys trapped in there. I've been doing the first weld by hand so I can be sure I've moved all the flux out without creating any wee bubbles. Second or third heat I square the billet under the press. Then hammer time.:D