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I Forge Iron

RogerrogerD

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Posts posted by RogerrogerD

  1. Frosty, I too would have put a fold in it, something like this picture attached from a personal experiment, but I’m assured from India that it was not the case, and that their steel was thicker.     In my other life, I have written about the development of rockets here, http://www.standingwellback.com/home/2018/5/2/the-history-of-metal-cased-military-rockets-an-investigation.html  should you be interested. I’ll get permission from India and post some of their finds, which I think are fascinating. 

    6147A657-E6B1-4602-8A9A-36150D1A3503.jpeg

  2. Thanks TP, that’s useful. I have a copy of the Golden age of Rocketry. Indians have found some rockets, and examined them, but cannot find any apparent seam, but they are pretty rusty. From what you say, it’s possible their work simply hammered out the seam.  Someone is suggesting the forge welding would have been done at 600 C, (1100F) but that seems a little low to me, for steel 2- 3mm thick...any thoughts? Congreve takes a lot of credit, perhaps too much, and it’s clear the Indians were producing, in quantity, metal cased rockets a decade or two before Congreve, whose  contribution was a more formal, repeatable  industrial process and consistent propellant  My own contribution was highlighting that Irish rebels in 1803 used metal cased rockets against the Brits, (designs provided by the French who got them independently from the Indians..) and one of those rebels ended up working for Congreve... Congreve did have access  to captured Indian rockets,  but there is little in the archives. Two are in deep storage in a museum in UK and we cant have access. Congreve was very secretive... . But now the Indians have recovered so many rockets (in a well!), they are conducting research. Im meeting one of their team next week, so wanted to check some of the engineering concepts of manufacture. 

  3. I’m involved in a historical project looking at how the first metal cased rockets were made in the late 1700s, and I’m interested in drawing on the expertise of the forum.  So... if you had to make a cylinder, say 2” or 3” in diameter 12” long, from sheet steel, (wrought, I assume, possibly low  carbon), you can roll it into a cylinder but it then needs welding longitudinally. My questions are :

    1. Roughly what temperature would be needed?

    2. Would you expect to be able to see a seam when you finished or would it all be apparently homogenous? 

    3. How thin would you be able to get your starting sheet steel? 

    4. What tools would you use? 

    5. Any other thoughts on how one might have made significant quantities in India in say 1790? 

     

    Thanks in anticipation

  4.  Hi, fellow Brit here.  It won’t be cast iron. “Cast iron” is too brittle. It’ll be cast or wrought steel. Looks like a nice anvil.  It looks wrought to me, and therefore I would guess quite old. Maybe mid to late 1800s.  I’d say the face will be probably forge welded hard steel and in the first pic I sort of see the line at the level of the front table, about 1cm thick. Normal. The texture of the face looks to me like a combination of normal work and some rusting at some stage in its life, giving it a slight stippled effect. The edges look really very good, unusually good for an old anvil... and that’s important, more important than a perfectly smooth top, I’d say. It looks like a great find. In my opinion, use it as it is, no need for anything other than a tree trunk to stand it on.

  5. Looks like burnt carbon steel to me, caused by overheating.  Spring steel has highish carbon and more likely to “burn”.  Burning can cause “goops” of steel that look like “cottage cheese” to some people I guess. The burning effect will damage steel up the bar beyond the goopy stuff, which is why some is fracturing on you.  I’m guessing you were using a coke or coal forge rather than propane which is I think a bit cooler. If you are using a coal/coke forge, maybe get it nice and hot and them turn off or dont blow the air as you stick the steel in. Less oxygen I think you’ll be less likely to cause this effect. 

    Also.. I am forced to have my forge outside, and its tricky to see the colour of the steel in sunlight. So I have burnt lots of steel, as I began blacksmithing. What looks an ok temp to forge in the sun is whitehot in the shade. Are you inside or outside? 

  6. Looking carefully at the third picture, it does look to me like a hard steel plate has been properly forge welded on the top, so it doesn't look “fake” to me. Just poor quality body perhaps. A hardy is nice to have, but not essential, perhaps. If you have a use for it, keep it, if not some beginner blacksmith would probably take it off your hands.

    I think the brand is Australian... if you google back you’ll see an identical anvil with an identical flaw here from 2015, amd reference to an earlier post with again a broken heel on the same brand. Looks like they were simply a poor make. 

     

  7. Aluminium doesn't hammer well. You cant really forge it at all..  Brass will do, but only in certain circumstances and not like steel. Copper work hardens, so you need to anneal frequently and  it doesnt really move like steel.  Plasticene works on a very basic level to see how metal “moves”. Steel is cheaper than copper and brass, so you dont save anything. Get some scrap steel and get hammering. 

  8. On 3/9/2019 at 12:18 PM, Stew1803 said:

    Coming from Scotland I say that - I see more gas forges than coke or coal, almost all coal or coke forges ive seen have been bottom blown,  I use and know others to use borax,

    Interesting differences. Im in the costwolds and its not my experience round these parts, but I admit to having limited experience. Or I’m mixing with the wrong bunch of sassenachs. ;- )

  9. FWIW, I’d say use it. As a tool it was meant to be used.  My anvil is nowhere near as old as yours, but it gives me a thrill when I use it as it was intended 100 years ago.  Id love to make something with a tool that was 300 years old. What a buzz that would give. Yes you could damage it, but hey, its lasted this long, it’s tough!  Whatever you do simply adds more to its history.

  10. Speaking politely... how patient is he for his knives?  I’ve been blackmsithing for nearly a year and I’m a long way off being capable of doing a set of knives that I could give anyone...  Learn to walk before you commit to making knives....   if it were me I’d be up front, take the anvil, but be clear it’ll take you some time to learn the skills. Offer him some hooks and bottle openers to start with. 

  11. So I think this will work without a thrust bearing or washer if it has to.  But in an idle moment I  measured up the dimensions for a thrust washer. Came to 45mm internal dia and 65mm external dia.(sorry, a Brit here working in metric). I could make a washer up easily enough I guess, but I fed those dimensions into ebay and amazon , just for the xxxx of it, in case I could get a washer cheap through amazon.  Not surprisingly I drew a blank, I had assumed those dimensions for a 100 year old or more object would be esoteric.  But, but...at the bottom of the page was offered a thrust bearing, of exactly those dimensions for the princely price of £4.55  (about $6).  So for that price I ordered it... arrives from China shortly. How weird is that?  Jeez, i would expect to pay twice thst for a simple washer of those dimensions.

    If I fit one of these (with a thickness of 14mm) the vice will close with the key up or down... not sure if the thrust bearing will cause the handle to flop about. We’ll see. I’ll  report . 

  12. Yep the jaws will close completely if I squeeze by hand so it must be the mouse’s walnut in the box... I’ll take a stiff bottle washer to it this afternoon. 

    So I gave the screw box a thorough clean out, and regreased it lightly. Refitted, no different, still not quite closing. On a whim I then took it apart again and refitted it with the “key” on the screw box down rather then up...and guess what,  it closes....

    I can't think that there is any negative on which way up the screw box is fitted.. the space it slides through between each jaw is slit snd drifted and not precisely machined, and there’s space for the key either way.  I didnt expect that.  I dont recall which way up it was when I first got it,   because I wasnt looking, and I cant make it out on the photos I took. 

    Ah well... it works, and for the heck of it, I’ll try a cheap thrust bearing thats on its way. 

  13. You're gonna need a bracket to fix it to a stand of some sort...and the bracket on a traditional vise incorporates the top of a normal spring.  A normal spring meeds nothing at the bottom other than an ear on either side.  So do you have a bracket and if so would it hold the top of a traditional vise spring?

  14. I’d buy a post vice in poor condition and salvage the box or box and screw. I’ve seen some in the past that were really sticks of rust but becuase the screw threads were the only thing still covered in a layer of grease and somewhat protected from the elements, it meant as components they were fine. Get a box and a screw and you dont need to worry about a match. 

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