San mai on small rolling mill

[Natlek]

Don t push me You know that I don t give up that easy.......I will make if necessary roll mill with one meter Dia. rollers , IF i know that that will work

 

[Natlek]

Searching about this i found this plans , maybe someone will find them useful....
https://www.yumpu.com/en/document/read/16321793/steel-rolling-mill-hugh-mcdonald

 

[chumaman]

Don t push me You know that I don t give up that easy.......I will make if necessary roll mill with one meter Dia. rollers , IF i know that that will work

no way to push

 

[Willie71]

Both of those appear to be McDonald rolling mills with foot pedal actuation. (You can see the guy's knee in the first video on the right kicking down the pedal) They're not developing huge tonnage.

I think the problem with setting welds in a rolling mill is likely going to be too much deformation causing delamination on the end not currently in the roll. With a full perimeter MIG weld around the seams, that may be prevented. Otherwise it's no different than trying to set welds in a hydraulic press with round drawing dies. You can to it, but it's a lot harder than with nice big flat dies and even pressure.

Drawing evenly once welded, to thicknesses very hard to accomplish with a press, seems to be a rolling mills biggest usefulness.

I made the simple mistake of leaving the moderate drawing dies in the press after drawing, and trying to set the next weld. I did it, but it’s much easier to just use the flat dies.

I’d like to have a rolling mill, but a surface grinder comes first. I wouldn’t use a rolling mill to set welds, but drawing out san Mai seems to be the ideal rolling mill use.

 

[weo]

Since it seems as Natlek would rather this conversation head more towards the theory side of things instead of the actual practice...

I'd think that if you could ensure that the weld line is in the exact center of the rollers, then this could work as there should be limited shearing and mainly compression happening here. Once the weld line gets out of the exact center of this line, there I can see there be increasing shearing, especially if the rollers aren't exactly the same size, causing the billet to bend..

 

[weo]

Don t push me You know that I don t give up that easy.......I will make if necessary

I say do it, and if it doesn't work for welding, I may buy it from you for drawing out billets with minimal distortion of the pattern.

(Depending on the cost to ship, of course ....and if you don't use the 1mm rollers....)

 

[Willie71]

I say do it, and if it doesn't work for welding, I may buy it from you for drawing out billets with minimal distortion of the pattern.

(Depending on the cost to ship, of course ....and if you don't use the 1mm rollers....)

At the last hammer I was at, the host had a rolling mill to draw out billets. They said the pattern distorts a bit, in a chevron shape. Something to consider.

 

[Natlek]

I say do it, and if it doesn't work for welding, I may buy it from you for drawing out billets with minimal distortion of the pattern.

(Depending on the cost to ship, of course ....and if you don't use the 1mm rollers....)

Well this is most simple tool to make , maybe I will .... I have laying around shop material to build ten not one I have five parts/rollers like this one , and I can get more if I need them .This is 54 Hrc tool steel , my friend produce them for someone in France I think .And even CNC machine sometimes make mistake , so ....... I get waste .
They are surface hone/grinded and are about two inch Dia ....just as we need them

 

[tkroenlein]

I don t know............... what is happening when we rolling steel is this ......the material is pushed in the reverse , towards thick side ,BLUE arrow on picture ? Welding is happening outside of rollers/ and between rollers pass already welded steel ??? How that can shear/ delaminated weld ? Why I think that pressure is just in right place to weld ? I m just loud thinking .....

One more note .I think that jewelry roll mill is better for this because both rollers are driven by motor or handle whatever is ....that must make difference ?

That's not all that happens. Your material is also pushed toward the edges. It's going to "squirt" material on the backside, even if to a small extent. I think getting material hot hardnesses that are similar enough and dimensional uniformity close enough will be the devil.

 

[Nick Dunham]

As T tkroenlein mentioned, rolling mills indeed are indeed used for producing clad materials. This is done, however, with the idea that flow stress must be reached in the weld zone. Reduction is in the 30-40% range, as far as I'm aware.
N Natlek , if you want to read further, search for "hot roll bonding".

Also FYI forces in rolling mills push both ways, and there's a neutral zone where they balance.

But yeah, build one, try it out, if it doesn't work for san mai there are lots of other uses. I can certainly relate to the urban concerns for power hammers.

That said, I thought I saw a blacksmithing forging press (hydraulic) that had an auto cycle for drawing things out - you just hold the pedal down and it reciprocates your present stroke. That ought to be pretty versatile and consistent.

 

[Natlek]

As T tkroenlein mentioned, rolling mills indeed are indeed used for producing clad materials. This is done, however, with the idea that flow stress must be reached in the weld zone. Reduction is in the 30-40% range, as far as I'm aware.
N Natlek , if you want to read further, search for "hot roll bonding".

Also FYI forces in rolling mills push both ways, and there's a neutral zone where they balance.

But yeah, build one, try it out, if it doesn't work for san mai there are lots of other uses. I can certainly relate to the urban concerns for power hammers.

That said, I thought I saw a blacksmithing forging press (hydraulic) that had an auto cycle for drawing things out - you just hold the pedal down and it reciprocates your present stroke. That ought to be pretty versatile and consistent.

Thanks ! Another night without sleeping , thanks for that Now . quick search bring me to this video ....I m missing something or welding is made exactly as we want to do ??

I don t understand welding picture on video ..... ?

 

[Natlek]

Hm...............
Roll bonding is a method of producing roll-clad plates or sheets by hot rolling a welded composite of steel clad plate and a plate of a more corrosion resistant material, such as stainless steel.

Clad plate is produced by cleaning the two surfaces to be joined, which are then placed in contact. The edges of these plates are welded together to prevent air ingress and prevent the plates moving during the hot rolling procedure. A solid phase weld between the plates is achieved by furnace heating and then hot rolling.

Typical clad materials onto steel plate are stainless steel, nickel, copper, high nickel alloys and copper nickel alloys. Aluminium clad steel plate is also produced but care must be taken that brittle iron aluminide intermetallics do not form.

Clad plate finds major application in the manufacture of pressure vessels and tanks. Other areas of usage are machine tools, aircraft structures, wire, refrigeration plant, jewellery and coinage.

For further information please see Joining Technologies or contact us.

 

[Natlek]

Where is @Larrin when we need him

 

[weo]

That said, I thought I saw a blacksmithing forging press (hydraulic) that had an auto cycle for drawing things out -

I think that's on the press that JTknives made.

 

[Natlek]

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

 

[weo]

I don t understand welding picture on video ..... ?

Are you referring to the picture at 2:29? If so, I read that to say that welding the steel is a separate process and done before the rolling (at 2:38).

 

[Natlek]

Are you referring to the picture at 2:29? If so, I read that to say that welding the steel is a separate process and done before the rolling (at 2:38).

Yes ..but look further on 2:38 ...rough rolling. Looks like only end was welded ? Maybe they mean on welding sides with billet welding ?

 

[weo]

Yes ..but look future on 2:38 ...rough rolling. Looks like only end was welded ? Maybe they mean on welding sides ? billet welding ?

I saw that darker red line to represent the core material and the outside red to represent the cladding.

 

[Natlek]

on 2:38 red is outside and on the ends .... and black is inside...?

 

[weo]

OK, so not dark red. I saw the black line as the core metal and the red as the stainless cladding.

And to have a completely stainless piece, the cladding would need to be completely surround the core metal, so yes, as you said, "outside and on the ends"