Working Wrought Iron

[FERRARIVS]

Does anyone have a deal of experience working with wrought iron? I'm just now making my first foray into the technique and man is it dodgy. I've learned that iron is best hammered quite hot, and through trial (and much error) lighter hammerstrikes seem to cause less problem, but I still get a good deal of splitting and cracking- fine stuff, sure, but still visible after grinding and much can't be ground away so is deeper. Of course I'm working a 3/4" round bar down to about 3/8" square so it's a good deal of forging, but there must be a way- smiths forged iron down to nails for thousands of years before decent steel came along. Does anyone have any advice?

[David Einhorn]

First I need to make sure that we are using the same terms. If the material that you are using is antique hand-puddled wrought iron material complete with silica and having different and varying grades from low grade wrought to high grade wrought, then that is a whole complete subject in itself. My suggestion would be to use either mild-steel or "3/8 inch drawing wire" instead as *real* wrought iron material is usually worked at or near a welding heat if it is low-grade.

If you mean that you are forging mystery metal from the junk yard to make nails, again that is an adventure in itself.

If you mean that you are having problems forging mild-steel then again you are not forging it hot enough if it is cracking. Also with mild-steel, light hammer strikes is not your solution either.

[double_edge2]

if its the real grainy type wrought iron keep it hot and dont move it too far too quickly without the hammer or swedges to keep it together. i had to lots of cover up tapping, or it shows its very strandy self. to be honest, i had to start another peice and go slower.

[FERRARIVS]

@UnicornForge- I really mean exactly what I wrote: wrought iron means wrought iron- fiberous, 120 years old metal (in good shape). And I am using it specifically- the size is what I need and the material is what I need. I've used mild steel a lot, so that I have no trouble with- I'm intentionally learning to use iorn since it's so different.

Actually, it's because it's a whole subject that I ask- there's not a heck of a lot of information within easy reach it seems, I've looked a fair bit. It strikes me as something that'd be useful to have here.

Unfortunately, I don't know if the stuff I have is high or low grade- it's cut 90% of the way through, then broken so the fibers are visible but the fibers don't look big and the sawed section is clean, i.e., nothing visible to the naked eye, but for all I know that's what low-grade stuff looks like and high grade wrough iron has barely visible fibers.

@double_edge2

I hadn't thought of using anything to mechanically keep it together, but that's not something I think I can do at the moment since I don't have a swage block or anything analogous. Gentler and slower was the one thing I was afraid might be recommended LOL since I'm already going pretty slow and drawing out what I need to draw out is taking a good long time. It's the only thing that had occurred to me since my first attempt caused so much real cracking and I was striking as hard as I would using mild steel. Near welding temperature makes sense too but again is not what I was hoping for since that's more time and even less working time. But then anything's better than all the fine cracks I guess...

[FERRARIVS]

I find myself wondering more about techniques though since super heat is rather less efficient a compensating method when one thinks of the ancient smith using probably not invaluable charcoal- things like forging round-section for drawing since stresses on the fibers might be more at the corners?

[arftist]

It needs to be worked much hotter than mild steel. What type of forge are you using?

[FERRARIVS]

It's a Diamondback Ironworks single-burner propane knife forge- it does get quite hot since I can weld with it, although I'm still not so good at it yet ;)

[ThomasPowers]

It's hardf for most of us to use real wrought iron as it likes working at high welding temps---where mild steel would be burning up and most of us are well trained to avoid that high a heat.

When it's way hot it forges like butter and so the time involved goes *WAY* *DOWN* on doing stuff, much faster to forge than mild steel at lower heats.

OTOH your forge needs to be set up for working at that temps; Air and coal/charcoal supply that you can get away with for mild steel may not work well at all for WI.

Also since it forge welds beautifully many things that we do today by drawing down larger stock was done back then by welding up stuff to make the preform you need for forging.

Also are you working alone? Back in the wrought iron days a single smith at a forge would be about as common as an operating room today with only the surgeon in it. Strikers help speed things up.

"Practical Blacksmithing", Richardson, is a collection of articles from a smithing journal back when they were switching from WI to MS and so will have ideas on the methods used and changes to those methods. Copies are easy to find.

[Mark Emig]

In my experience, you need to start working wrought iron at just about a welding heat (most gas forges just can't bring wrought iron to a white heat) and just as importantly STOP forgeing at a high orange heat. When I worked wrought iron down into the oranges, it split more. Also, always work from the tip of the bar towards the back-helps to control the splits. If it does split, just bring it to a welding heat ( wrought iron welding heat is hotter than steel welding heat) and weld the splits closed.
Mark
Mark

[David Einhorn]

@UnicornForge- I really mean exactly what I wrote: wrought iron means wrought iron- fiberous, 120 years old metal ...- I'm intentionally learning to use iorn since it's so different..

Sorry, it was just very unexpected that someone would be wanting to make nails out of wrought iron. :D

[irnsrgn]

If its old Wagon tire iron its low grade and if you get it too hot the first time it explodes into fragments, after working it lightly with a hammer it refines it some and can be worked at a higher temp.

Wrought works like butter, you work it at a higher heat (yellow) than mild, but if you work it past bright orange it splits bad.

[FERRARIVS]

@ThomasPowers Absolutely- I was pretty wary of the color at first but the specter of cracking got me over that one pretty quick LOL And yeah, today I did find it was a xxxx of a lot easier than any steel piece I've ever made- although the really short hammering time and going back to the heat so often did seem to make it take no less time. I tried welding some small bits into a large billet, but I hadn't yet found that the working temp nees to be so high so I had horrible splitting problems- I'll have to give it a go again now that I know. Yeah, I'm by my lonesome so I'm sure that makes a significant difference- ah for the days of apprentices to do the grunt work. Thanks for the reference suggestion- I'll have to check it out since I've so far been singularly unsuccessful in finding any written material on forging iron.


@Mark- I did go much hotter today and it seems to have helped some- I suspect there's technique I need to learn too- drawing is probably one of the more 'energetic' processes and it sure seems wrought iron doesn't much like those. My other desire is to hammer out a thin sheet- that's already been a failure once so I expect it'll be a tough learn too. I realized leaving some mass at the end would control splitting although I promptly forgot it earlier and ruined 45 minutes' work when I tried to draw out a point from a short end and it cracked and split all to xxxx - welding didn't work to save that one. Drawing points seems one of the real difficult things to do in iron...

@UnicornForge: Oh I'm not making nails- I just said that I understood part of my issue was that I wanted to draw something out significantly but that there had to be a way to do it cleanly because smiths made nails out of iron for a very long time (which are significantly smaller than what I am doing).

@irnsrgn: Luckily my stock is round and square bar- seemingly of higher quality since the fibers are quite fine and even with a 10X magnifier I see no slag inclusions or anything but the tiny fibers.