newbie questions on bending round bar stock

  1. julianf

    julianf Member

    Messages:
    2,990
    Location:
    devon, uk
    Ive never done this at all before, but i have an idea for somthing made from, probaby, about 1/2 inch round bar stock, formed into this kind of shape -

    [​IMG]


    Basically just curvey bar stock. Scale will maybe be lengths about 1.4m or so.

    Really i have no idea where to start.

    What i want to achieve is smooth natural looking bends - the bars will start at a base, all together, and end at specific places to support other items.

    Im not convinced 12.4mm bar stock will be enough to stop wobble / spring, but i cant see myself being able to bend thicker - if that!


    Can someone give me some pointers please?
     
  2. Country Joe Argoshield Dark

    Messages:
    1,082
    Location:
    Somerset - United Kingdom
    Hi there,
    As they're not very tight curves, you should be able to do it by hand.
    When you've got a length in your hands, I think you'll maybe find it much easier than you imagined.

    I'm not exactly a gorilla (look a bit similar, but much smaller!), and I don't find it difficult.
    It would bend very easily in a vice.

    All the Best,
    CJ
     
    Gwil likes this.
  3. Paul.

    Paul. Moderator Staff Member

    Messages:
    5,402
    Location:
    Northampton. UK
    If you buy hot rolled bar as opposed to bright bar it will bend very easy, all you need is a couple of round bosses or similar welded to a plate or even tacked to the bench, feed it between them and bend it by hand bit by bit, done loads of this even with stainless, once you get the feel for how much to lean on it its very easy.
     
  4. julianf

    julianf Member

    Messages:
    2,990
    Location:
    devon, uk
    Ok, thank you.

    Is there any way i could reduce spring / wobble on the finished item by what metal i used to start with?

    Basically i want a set of control panels supported by this "hydra" type thing, and the controls will be used, so i need to make sure its not too crazy.

    I know that making it with box section etc. would be physically more functional, but then i wouldnt get the aesthetics - it needs to look right too.
     
  5. KemppiFrog Member

    Messages:
    2,510
    Location:
    Aquitaine
    If each 'frond' is separate at the control panels, then there will be some flex. If two or more are used to support a panel, then things get a lot stiffer.
    I was just bending 10x30mm bar with a hand jig. Not difficult with gentle curves and 12.5mm hot rolled bar would be a doddle, as Paul says.
    I will stick up a pick of my jig.

    Here ya go, that is a bit of 16mm in it
     
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  6. julianf

    julianf Member

    Messages:
    2,990
    Location:
    devon, uk
    I did consider pairing them up, but to keep the effect, they would probably need to be close to one another, and then that would mean identical bends if it wasnt to look messy, which is probably too much for a novice to consider.

    The panels on the ends have minimal weight, but i think it will still spring.


    I should probably just try it, i guess.
     
  7. KemppiFrog Member

    Messages:
    2,510
    Location:
    Aquitaine
    Just try one and see if the flex is acceptable with one end in the vice, don't even have to bend it. That 16mm above would not move much.
     
  8. julianf

    julianf Member

    Messages:
    2,990
    Location:
    devon, uk
    Im good to use 16mm, i just did not think i would have any hope of bending it.

    I have two steel places, one is within walking distance, but only does full lengths, the other is near my partners work, but has a pile of pocket change off-cuts.

    Ill see if i cant persuade her to call in on her way home... (yeah, i know, but ive managed it before....)
     
  9. KemppiFrog Member

    Messages:
    2,510
    Location:
    Aquitaine
    My place is about 10 mins drive, but you can cut bits off lengths and are charged by weight and it is still much cheaper than the big place that only sells full lengths. Slightly more limited choice of sizes, but not a prob.
     
  10. Thrashsmith

    Thrashsmith Member

    Messages:
    443
    England, Kent
    You're going to want a flat surface under the 16mm bar as you bend it so you can be sure that as you're pulling it around, you're not also pulling it up or down. If you pull it up or down at the same time you'll end up with a series of bars that kick up and down along their length and won't lay flat.
    Either that or you'll have to very reguarly lay the bars on something flat as you're working them to make sure they're not kicking up/down.
    Also having concave objects or surfaces can be useful for making bends in bars and/or for straightening. E.g a gently swayed back anvil face can be very useful for bar straightening. The bottoms of oxygen cylinders have a concave bowl shape which can be very useful when cold bending - if you can safefly and legally cut the bottoms of them off. Carefully balance the bar across the bowl shape and strike down with a rounded face hammer.
    If you haven't got any of those things then I'd suggest sourcing a large tree stump and grinding out a long gentle dip in it so you can flatten back down the kicked up parts on that.
    Sorry if that's insulting your intelligence but I don't know what tools you have at your disposal.
     
  11. julianf

    julianf Member

    Messages:
    2,990
    Location:
    devon, uk
    Don't worry about dumbing it down for me - I hope I'm clear in that I don't know about this stuff.

    As for having all the curves in the same plane, providing I'm not trying to make matched pairs, which I think will be too hard for me anyhow, then I would specifically want the bends to be in different planes anyhow.
     
  12. fixerupper

    fixerupper Member

    Messages:
    1,172
    Location:
    Crete Greece
    bending bar freehand is a bit like drawing in free space, I've done a bit... I found having a length of tube about 700 mm that fits over your bar to give you more leverage , and control where the bend bends , and a bit of steel in the vise with a hole drilled in it the a bit larger than the bar you are bending, a pair of gloves ... sometimes I've jigsawed 18 ml ply to give me a guide ...if I'm working to a fixed design...hope this helps ...have fun
     
  13. Thrashsmith

    Thrashsmith Member

    Messages:
    443
    England, Kent
    We may already be on the same page but just incase we're not - I'm not solely talking about their vertical up and down bend shapes (regardless of whether they're individual or paired) I'm talking about controlling how much they bend in and out.

    Making matched pairs would be time consuming but not impossible if you are aiming to make them flat, i.e so they only bend up and down. Making matched pairs that bend up and down AND in and out is another thing all together.

    If you're saying you're happy for them to all bend up, down, in & out and for each one to be a very 3D like tendril, then ignore what I was saying about how to flatten them down.
     
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