San mai on small rolling mill

[Nick Dunham]

The more i read the more i'm confused Is there someone to sell me sanmai
That is the process and I still don't understand what I don't understand

That's stainless coming off a coil, being applied to carbon steel (either coil or discrete plate), going through what's probably a radiant tube gas-fired furnace with argon protective atmosphere, then a 4-high mill. 4-highs give you added rigidity with moderate-diameter work rolls. There may be an automated edge welder, or they could be using the pressure atmosphere alone to prevent oxidation. Remember a lot of these diagrams and animations are simplified and not always 100% representative, including 2:38 in the video. If you want to find specifics, you will want to look at scholarly sources - journal articles and older patents. They will generally tell you exactly want they did, the variations they tested, and what those variations resulted in.

As to the cladding welds on the video, I bet it's welded all around, then those edges are cut off. There isn't necessarily a need to completely encase the base metal, except for the cladding process. For two-layer clad material, sometimes they'll double up in opposite directions to prevent curling. That may be what the video is showing at 2:25. The base metal may be lapping over the ends for a variety of reasons - but again, the video isn't necessarily representative, and there are many different variations of this process - including one where they bond two SS sheets inside a sacrificial canister.

If you want to buy san mai, there are lots of people that sell it - in Europe, I think you can get Hitachi clad, and Balbach Damast is in Germany. Oblivion Blades in Australia does some, including made to order. I know I've seen members here offer it for sale.

 

[chumaman]

In Bulgaria, which is closer to him(Keltan) has a tempting one
N690/K390/N690 265x38x3,8mm cca 130EU

 

[Natlek]

In Bulgaria, which is closer to him(Keltan) has a tempting one
N690/K390/N690 265x38x3,8mm cca 130EU

130 EU .........I will pay that kind of money just for information that it is made on roll mill
Send me email with link to that , please .....

 

[Natlek]

K390 .........with 9 % vanadium ??? No , thanks At least not this year, no more hand sanding , enough is enough ..... I have a life to

 

[jake pogg]

Lots of very interesting info above,and i must concur with most(if not all)main points brought up.

Rolling is probably not the best way for Setting the initial weld,mostly for it's English wheel-type action,i.e. the distortion vectors in multiple directions,some definitely counterproductive.

Possibly that can be gotten around in some way,like maybe rolling inside a couple HSS plates...Or unless one makes a very light-pressure pass,where distortion would be a minor issue or not at all.

Not having any experience with this i'd say that it can be done,with the usual dose of experiments and initial headache...

However,i'd personally go with what seems to be consensus hereress,or hand-hammer,for Setting the weld.
(For further drawing out i can see Any roll-mill working,possibly even some dirt-cheap amazon hand-crank job).

I'm not much on technology,Controlled Hand Forging has been my thing for a couple decades now,but it's a good teacher,whatever else one can say about it.Developes good intuition.So intuition is what i use for problem-solving...And keeping in mind that old saw,"Tools don't make a blacksmith;blacksmith makes the tools".

Setting an initial weld doesn't require great pressure;i'd not be surprised if it can be accomplished in a non-powered press.Some form of fly-press,or a hand-cranked bottle,or even simply a levered tortilla press type device...I've closed welds quite effectively with a stout set of tongs before,right in the fire...
The idea is to only bring the corresponding parts to bear,excluding oxygen and crap.
After this it's the function of successive heating(Time,for further bonding to occur), and manipulation(to further assist the bond by pressure while avoiding ruining said bond).

 

[Natlek]

Lots of very interesting info above,and i must concur with most(if not all)main points brought up.

Rolling is probably not the best way for Setting the initial weld,mostly for it's English wheel-type action,i.e. the distortion vectors in multiple directions,some definitely counterproductive.

Possibly that can be gotten around in some way,like maybe rolling inside a couple HSS plates...Or unless one makes a very light-pressure pass,where distortion would be a minor issue or not at all.

Not having any experience with this i'd say that it can be done,with the usual dose of experiments and initial headache...

However,i'd personally go with what seems to be consensus hereress,or hand-hammer,for Setting the weld.
(For further drawing out i can see Any roll-mill working,possibly even some dirt-cheap amazon hand-crank job).

I'm not much on technology,Controlled Hand Forging has been my thing for a couple decades now,but it's a good teacher,whatever else one can say about it.Developes good intuition.So intuition is what i use for problem-solving...And keeping in mind that old saw,"Tools don't make a blacksmith;blacksmith makes the tools".

Setting an initial weld doesn't require great pressure;i'd not be surprised if it can be accomplished in a non-powered press.Some form of fly-press,or a hand-cranked bottle,or even simply a levered tortilla press type device...I've closed welds quite effectively with a stout set of tongs before,right in the fire...
The idea is to only bring the corresponding parts to bear,excluding oxygen and crap.
After this it's the function of successive heating(Time,for further bonding to occur), and manipulation(to further assist the bond by pressure while avoiding ruining said bond).

Thanks for taking time to to express your opinion about this Obviously only way to see if roll mill will successfully weld sanmai is to try I have collect all parts to build ... two of them .One to reduce the thickness and one just for sanmai with very small/precise movement of rollers. Luckily the local brewery is changed the production line completely so I get almost for free two electric motors with gearbox/reducer of speed . .I have feeling that there is way to do that .......... intuition
I found other source for work principles of roll mill which give me some ideas for experiments .....will see
If someone want to read it , it start on page 51
http://www.iitg.ac.in/engfac/ganu/public_html/Metal forming processes_full.pdf

 

[Natlek]

Possibly that can be gotten around in some way,like maybe rolling inside a couple HSS plates...Or unless one makes a very light-pressure pass,where distortion would be a minor issue or not at all.
Not having any experience with this i'd say that it can be done,with the usual dose of experiments and initial headache...

I thought about it but I m afraid that HSS plate will draw temperature to fast from steel. very light-pressure pass,where distortion would be a minor issue or not at all. that is what will work , I hope What I can do is to play with speed of rollers and their size ?? For that reason I need to make that roll mill modular construction so i can easy change parts which make build little complicated ...
Just looking in this picture i can see what difference make size of rollers..........

 

[jake pogg]

That is one Cool document,thanks!
Really enjoyed looking through practically all of it.

Yes,it seems that large Dia./low speed/low pressure/distortion principles would be conducive to your objective.

I'm still not clear as to how the constructing of all this set-up would be justifiable(within your stated goal of a couple-three blanks for personal use/enjoyment),but it sounds doable,and actually cool....Building jigs and tooling Is a cool thing to do.

(if you can enclose such a rig in a common shrouding with a well-adjusted gas forge,and squirt the billet after heating right into an argon-surrounded roll-mill......why,then you'd Really be ahead!

 

[Natlek]

Into an argon-surrounded roll-mill..... It can be done , but....... Well , plan is to weld all perimeter with TIG .If I m any good in something that is welding....Steel I will use is flat as it can be ......that will help I hope .I will weld perimeter in this way .I will use hydraulic press to weld perimeter on that uncle Sanmai sandwich to weld them tight as it can be

 

[Natlek]

I'm still not clear as to how the constructing of all this set-up would be justifiable(within your stated goal of a couple-three blanks for personal use/enjoyment),but it sounds doable,and actually cool....Building jigs and tooling Is a cool thing to do.

I like to make tools ..... I do that all my life I build Go-kart when i have ten years

 

[Natlek]

Lots of very interesting info above,and i must concur with most(if not all)main points brought up.

Rolling is probably not the best way for Setting the initial weld,mostly for it's English wheel-type action,i.e. the distortion vectors in multiple directions,some definitely counterproductive.

Well , they are all wrong !! Only reason that i have still unfinished roll mill is this thread !
I should have followed my instinct and knowledge i have about mechanics .............
All of you who commented in this thread and think that my idea would not work ............. WATCH this video clip

 

[Natlek]

Yeah, I have no experience rolling metal beyond the 40+ years I have done it. I roll mokume, silver, and gold regularly. As I said, I have multiple rolling mills. I have used a press many times to weld a bilet up. You control the "bite" by the foot pedal.Press just enough to set the weld. The speed of a knifemaking press is usually about 1.5IPS. Slower will work, but the loos in weld time is a lot. I can weld up a 6X2X2" billet in one heat on a press.

But do your own thing. Have fun doing it and post your results.

I'm gone.

40+ years ..............................Like it !!

 

[Natlek]

Well,not in a couple of days ...after a few years, but it's never too late, right?

 

[A.McPherson]

Glad to know you got something that works for you, that's awesome!

 

[DevinT]

Well,not in a couple of days ...after a few years, but it's never too late, right?

Nice victory lap even though you don’t have a rolling mill and you have never made a single bar of sanmai.

Even if you finish your rolling mill, there is a learning curve.

I’ve made thousands of bars of sanmai but refuse to help you because of your arrogance.

Hoss

 

[Natlek]

Nice victory lap even though you don’t have a rolling mill and you have never made a single bar of sanmai.

Even if you finish your rolling mill, there is a learning curve.

I’ve made thousands of bars of sanmai but refuse to help you because of your arrogance.

Hoss

This guy is still mad at me As if it's my fault that someone is using toaster oven and the cheapest HT oven for experiment

You made thousands of bars of sanmai..................? Good for you ...you do that for living .I do this for fun .
My arrogance ? Maybe I m arrogant sometimes WITH reason .................... When I was ask you for help ??
I didn't know you were clairvoyant ? You're not good at it at all................

First san-mai weld

Yes , I used stainless rod with my arc welder , that s all i have in home . In my service i have Mig .....Tig , but ordinary welder do it well ........ When forge welding i use hammer on whole blank .I hold hammer close to head so that I have more control over the blow , not to make deep dents...

bladeforums.com

Now , if you have nothing to add on topic in this thread , please......................

 

[Natlek]

I’ve made thousands of bars of sanmai but refuse to help you because of your arrogance.

Hoss

This is priceless guys ...........he refuse to help me , imagine that .Now i will never make sanmai This is bladeforums.com treasury of knowledge and there are many knifemakers willing to help , even to me !
Hey , thousands of bars of sanmai............why you don t upgrade your membership here like rest of knifemakers ??

 

[DevinT]

This is priceless guys ...........he refuse to help me , imagine that .Now i will never make sanmai This is Bladeforums.com treasury of knowledge and there are many knifemakers willing to help , even to me !
Hey thousands of bars of sanmai............why you don t upgrade your membership here like rest of knifemakers ??

You suck the life out of this forum every time you post.

Hoss

 

[Natlek]

You suck the life out of this forum every time you post.

Hoss

This forum have moderators to care about members behave .If you want to talk about me , find other place to do that . This is topic about welding sanmai steel on roll mill ............... so GTFO , please

 

[DevinT]

This forum have moderators to care about members behave .If you want to talk about me , find other place to do that . This is topic about welding sanmai steel on roll mill ............... so GTFO , please

Something is seriously wrong with you.

Hoss