dognose Posted February 17, 2014 Share Posted February 17, 2014 Let me start out by saying that this is not a long taper forged into a ring. What I'm attempting to do is forge a ring made from stock that is the same dimension throughout the length of the piece. For illustration's sake, let's call it 5/16" x 1 1/2". This drawing is a floor plan where the narrow section represents the 5/16, the wide section the 1 1/2. There is a 90 twist that slowly transitions from one end to the other. In other words, the 5/16 is standing vertically, and by the time it wraps around is laying on it's side at 0 degrees. I'm confused as to how to go about making this? Twist and then try and bend? Bend the easy way around and then try and twist? A combination of the two, or build a form and heat the stock with a torch as I work my way around? I can envision the form working, but it sounds complicated to build with many different angles. Is there something I'm not thinking of? Any ideas??? Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted February 17, 2014 Share Posted February 17, 2014 Greetings Dognose, I have done transitional scrolls similar to that ... At what you would consider the twist point forge as much material as you can to square than round and than twist the round for the transition and than forge back to square to complete the directional change.. I hope this is clear enough to help.. Forge on and make beautiful things Jim Quote Link to comment Share on other sites More sharing options...
dognose Posted February 17, 2014 Author Share Posted February 17, 2014 Unclear as to what you mean by the "twist point"? Theoretically, the twist begins an 1/8" from either end and changes incrementally along the circumference. Trying to envision your method but for my brain it's lacking too much info. Thanks for trying though. Quote Link to comment Share on other sites More sharing options...
BIGGUNDOCTOR Posted February 17, 2014 Share Posted February 17, 2014 I would twist it 90 degrees first, then form the ring. You will need to get the entire piece evenly heated so that you can achieve the most even twist along the entire length. It may possibly need to be made a little longer than required, then trim after twisting to get it to look uniform. Good luck, and let's see some pics of how they turn out. Quote Link to comment Share on other sites More sharing options...
yahoo2 Posted February 17, 2014 Share Posted February 17, 2014 there is a drafting tool called a french curve. that is the forged shape you are looking for when the piece is lying flat. from there on the twist and roll is up to you, I would stick a piece of pipe the size of the finished ring in the vice then heat the remaining straight-ish 3/4 of the metal, cool the just the tip of the end that is going to be rolled (so it doesnt crush) and clamp it to the pipe hard, you should be able to hold the other end and twist then slowly roll over the pipe as it cools almost in one motion. I have trouble describing the shape its sort of like the outside compounding curl of this tool but maybe a fraction shallower. Quote Link to comment Share on other sites More sharing options...
billyO Posted February 17, 2014 Share Posted February 17, 2014 If I'm understanding correctly, what you're asking involves no drawing out or other changes to the parent stock size, only twisting and bending, which is the way I'd approach this. Get a long, even heat throughout the whole piece to get the 90 degree twist you're looking for, then proceed to bend the ring, taking care not to change the twist, that will be the challenge. Good luck. Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted February 17, 2014 Share Posted February 17, 2014 From the illustration, I don't see a twist, I see the stock changing . So one would forge two even tapers on a square bar so that the one end has the long side 90 deg. To the other. Then turn the ring. It looks like a really good student project. Especially as its an outside diameter as opposed to an inside diameter circle. Quote Link to comment Share on other sites More sharing options...
Eddie Mullins Posted February 17, 2014 Share Posted February 17, 2014 This seems quite simple yet challenging. At first thought I would agree with your approach that no changing in dimension is required, but in practice I am not so sure Jim's approach or similar may not need to be employed. I might give this a whirl just see. I think it could have a few applications. Quote Link to comment Share on other sites More sharing options...
dognose Posted February 17, 2014 Author Share Posted February 17, 2014 Yahoo2, I should've mentioned the piece is 18" in diameter, that would be a tall order getting an 18" pipe to work around. Even my cone mandrel doesn't get much past 12". Billo0, If I had remembered to mention the diameter of the ring, you may have realized that that would require heating a 56" long bar evenly. I could see trying to heat 24" evenly, but not 56. Quote Link to comment Share on other sites More sharing options...
dognose Posted February 17, 2014 Author Share Posted February 17, 2014 From the illustration, I don't see a twist, I see the stock changing . So one would forge two even tapers on a square bar so that the one end has the long side 90 deg. To the other. Then turn the ring. It looks like a really good student project. Especially as its an outside diameter as opposed to an inside diameter circle. The drawing is 2 dimensional. Perhaps I should have drawn it in perspective, where it actually shows the twist. Not an easy drawing to do either. I thought of trying to make one out of clay, But it doesn't hold up when stretched to such lengths. I may have to issue a challenge, where I put up some cash to the first person that can forge one. One tip someone gave me is to use cold rolled steel, as it is a consistent alloy throughout the material and would not have any surprise soft or hard spots one could encounter in hot rolled. Quote Link to comment Share on other sites More sharing options...
Eddie Mullins Posted February 17, 2014 Share Posted February 17, 2014 Maybe you could make a small scale version out some lighter weight / softer metal than can be bent cold. Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted February 17, 2014 Share Posted February 17, 2014 Greetings Dog, Forming the piece into a ring is no challenge.. Roll a 1/4 x 1 1/2 form 18in dia and weld it to a plate.. You can than heat in small sections.. Forge on and make beautiful things. Jim Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted February 17, 2014 Share Posted February 17, 2014 Got cha, challenging either way. You should be able to cold twist an annealed bar,, especially 1018. And again as your working on on OD circle you need 18" ID pipe (I guess because I live in gas and oil central 18" pipe dost sound like an issue) again with a such a long bar, one could cold form it to appropriately large die. I use a wooden mallet to convince it in to the form. One might also consider an 18" OD (use the ID) and over lap the ends, as your stock will spring out if formed cold. The pain in the butt will be sweet talking it into laying either laying on a table, or fallowing the center line. Then again there is probably some hard head out there that can forge it all on the anvil. Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted February 17, 2014 Share Posted February 17, 2014 Greetings Dog, In a pinch I have used an old bicycle rim and a wood mallet .. Quote Link to comment Share on other sites More sharing options...
bigfootnampa Posted February 17, 2014 Share Posted February 17, 2014 As I would approach this challenge... I'd use a bending form (pipe section, ring, heavy disc) I would get a full heat on the metal to be bent (cut at least a few inches over length) and then clamp the vertical end and twist with my tongs then wrap the curve, all in the same heat and motion! I might try it the other way round either (clamping the flat end) as that would enable me to complete the hard-way bending while the heat was freshest. Either way the key is a very long and even heat combined with a swift, smooth, twist and bend! A few inches of extra length is important as you'll need a bit of space for the clamped end and enough extra on the other end to give leverage for the bending. Admittedly the long heat is a challenge! If it seems too much I might try bending it in the same manner cold! Done cold the form would need to be a bit smaller diameter to allow for some springback. The twist likewise over twisted a bit. Quote Link to comment Share on other sites More sharing options...
dognose Posted February 17, 2014 Author Share Posted February 17, 2014 Greetings Dog, Forming the piece into a ring is no challenge.. Roll a 1/4 x 1 1/2 form 18in dia and weld it to a plate.. You can than heat in small sections.. Forge on and make beautiful things. Jim Jim, so if I'm understanding you correctly, I should first find a way to make a transitioning 90 degree twist on a 56" bar while straight, then form it around a non twisting ring heating it in small sections as I work my way around? Quote Link to comment Share on other sites More sharing options...
Frank Turley Posted February 17, 2014 Share Posted February 17, 2014 I would be tempted to carefully cold twist in small increments having one end clamped in the vise and using helper stands. Then bend around a circular form in small heated sections, one heat slightly overlapping the other. You'll probably use light correction blows with a mallet after each heat. Sayings and Cornpone "Cold blacksmiths wet their beds at night." Tom Bredlow Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted February 17, 2014 Share Posted February 17, 2014 Ask two blacksmiths how to do something and get 5 different answers ;-)qs Quote Link to comment Share on other sites More sharing options...
yahoo2 Posted February 17, 2014 Share Posted February 17, 2014 18 inches dia is a fairly mild bend for 1 1/2" , I dont think it will challenge you much. Leave a few inches on the end with the difficult curl and cut it off after so you have some meat for a bending jig to purchase on. I make a thing called a stripper plate that fits inside a rotary combine harvester that is a very similar shape to the centre section you are proposing. I have made them freehand at just over a black heat in a few minutes in an emergency. Do you need the profile to be perfectly rectangular along the whole length? If that is the case it will need to be preformed with a slight wedge at one end running into a slight concave shape, that could be tricky. Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted February 17, 2014 Share Posted February 17, 2014 Greetings again Dog, I am trying to visualize your starter material ... If the width does not change ( 1 1/2 ) and we are only looking at the reveal direct on view I have posted a picture of a scroll that changes directions .. If the base material make a directional change at a center point I have a picture of a copy of Yellins style of transition . If you add pictures of cardboard cut out it would help.. Or If it is a commission up for grabs LOL I'm in.. You can do it Forge on and make beautiful things Jim Quote Link to comment Share on other sites More sharing options...
dognose Posted February 17, 2014 Author Share Posted February 17, 2014 Now we're getting somewhere!!!! That second image is close to what I'm describing, although it appears to be on a much smaller scale. Where the scroll leaves the parent stock is correct, but it fails to transition all the way to flat (or 90 degrees off the starting point) by the time it gets to the end. Also, mine would have no taper at the end. I'll try and make a model to post but even cardboard doesn't want to bend the hard way. I like the scroll in the first image as well. Hard to see what's happening at the transition from the pic, is it a simple 90 degree twist, or is there forging involved? Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted February 17, 2014 Share Posted February 17, 2014 Greetings Dog, Yes the 1st picture is forged to round as I described and then reformed to flat to conform to the transition. I hope I have helped you.. Sorry I do not have better pictures.. Forge on and make beautiful things Jim Quote Link to comment Share on other sites More sharing options...
dognose Posted February 18, 2014 Author Share Posted February 18, 2014 Thanks for all the suggestions to this point. I just made a crude clay model in a much smaller scale. Hope the pics help give a better visual for what I'm attempting to do. Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted February 18, 2014 Share Posted February 18, 2014 Greetings again again again Dog, It may sound silly but I would form twist this and a basic round on the horn of the anvil and than true to the correct diameter on a fixed ring. I am spoiled I have several large line shaft pulleys that I use on may acorn table. You can still accomplish this with a hold hoop welded to a bicycle hoop and a wood mallet. I hope I have helped you.. Forge on and make round things Jim Quote Link to comment Share on other sites More sharing options...
Judson Yaggy Posted February 18, 2014 Share Posted February 18, 2014 Steel prefers to bend at the point of least resistance. That means the thinnest spot, the hottest spot, the place between the fulcrums. Play with these variables and you can make your shape. Not easy to get perfect thou. Good luck. I'd go after this with a torch, bending forks, twisting wrenches, wood mallet, cone mandrel etc if the original design required minimal cross sectional change in the parent stock. It will want to bend more in the center of the bar where the leverage is the greatest and the bar is taller than it is wide. If a cross sectional change is allowed then this can be done with a forge, hammer and anvil. Hammer one end of the material till it measures the same as the other end but 90 degrees in opposition. Connect the ends of the bar with consitant tapers, at the midpoint of the bar the cross section will be square, on each end rectangular but 90 deg off. Bend over the horn, true up as required. IIRC this used to sometimes be a Journeyman's test. Quote Link to comment Share on other sites More sharing options...
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