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brightspark
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just be patient and let it cool naturally
outofthefire
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It's a brittleish joint, there's not enough carbon in mild steel for it to be really hard and brittle, but most distortion happens when the welds cooling and you could well make that even worse cooling it quickly. It's not work hardened though that's something different, using air is a lot better it won't cool it any where near as fast, but i'd take brightsparks advice and let it cool naturally.
A lot depends on the material and obviously a using a wet rag /misting the part is very different to dumping a bucket of ice cold water on it
Mild steel doesn't have enough carbon in it to be hardened or tempered so will react to quenching very differently from med carbon steels or alloy steels like say, chromoly. Austenitic stainless steels are very different again and quenching is often used to help limit/control distortion. Annealing of stainless steels often includes quenching too. Quenching (air, water mist, wet rags etc) is also commonly part of flame straightening
Mild steel doesn't have enough carbon in it to be hardened or tempered so will react to quenching very differently from med carbon steels or alloy steels like say, chromoly. Austenitic stainless steels are very different again and quenching is often used to help limit/control distortion. Annealing of stainless steels often includes quenching too. Quenching (air, water mist, wet rags etc) is also commonly part of flame straightening
Very true, and it is an accepted technique in metal shrinking in car bodywork where a stitch and stop method of welding in repair sections are used, it is done with a mist as opposed to a jet of water, and usually in conjunction with hammer welding to get a flat or double curved panel to its desired shape.
anto44
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when I did my training we would regularly quench practice pieces if we were running beads just to practice as it saved waiting for it to cool but were always told to never do it on a weld that was actually going to be used.
If you're just running some beads on a bit of plate quench it regularly so heat soak won't be a problem but if you're making something don't quench.
If you're just running some beads on a bit of plate quench it regularly so heat soak won't be a problem but if you're making something don't quench.
brightspark
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and if u have welded something up and u quench it and have to drill holes where u have welded it don't bother as u will knack the drill and it will be as hard as hell 
done it a few times filling in holes for re drilling that have been drilled off centre
done it a few times filling in holes for re drilling that have been drilled off centre
Chucking water over the part when you've finished welding won't but flame straightening (or bending, heat shrinking etc) works on pretty much any weldable* metal. Obviously material properties (thermal conductivity, co-efficient of expansion etc) effect technique etc, how well it works and how serious any metallurgical side effects are
The following links go into more detail but basically welding distortion and stuff like flame straightening/heat shrinking follow the same principle... stuff expands when hot and contracts when cold. Heat a lump of metal up evenly and it expands in all directions, as it cools down it shrinks and the result is no change in shape or dimension. Heat up one spot and the surrounding cooler material stops the hot bit expanding evenly so instead it expands more in the directions it can. As it cools however it's free to shrink evenly in all directions so it changes shape.
Google flame straightening and you get results like https://www.boconline.co.uk/interne...ls-of-Flame-Straightening410_113398.pdf?v=1.0 add shipbuilding to the initial search and you get a bunch more results including http://www.oakleysteel.co.uk/flame-straightening-thermomechanically-rolled-structural-steel which is more about effect it (and forced cooling) has on modern steels. Also get this book preview which is more about techniques for shaping this and straightening that https://books.google.co.uk/books?id...ge&q=flame straightening shipbuilding&f=false
* it'd physically work on stuff that's considered unweldable too but often 'un weldable' is more about the properties being ruined by lots of heat than being able to physically weld it
