Steel patchbox

[George F.]

I had to order a small sheet of sheet metal from McMaster-Carr, the local stores didn't have any thing thick enough. It's 1008 low carbon. I was wondering if I just start bending for the hinge, or do I have to do it red hot?  ...Geo.

[David Rase]

Mild steel will bend cold.  At least that is how I have done the half dozen or so steel boxes I have made.  There is not enough carbon in mild steel to work harden so you do not need to aneal it either.
DMR

[George F.]

Thanks Dave, I know we touched base on this before, but the local store had real thin stuff, so I had to order something.  ...Geo.

[B Shipman]

Why not just order by mail and get what you want?

[Chuck Burrows]

There is not enough carbon in mild steel to work harden so you do not need to aneal it either.

With all due respect to David it is not carbon alone that creates work hardening in steel - other elements, especially manganese contribute to work hardening and or fatigue - two different things when working with iron/steel. 1008 or any other mild steel can and often will work harden/fatigue if cold hammered on long enough or it's bent/flexed. I've learned that to my regret over the last beaucoups years of pounding iron. While one can get away with it IMO why take the chance" - heating it up is so easy and simple, especially since heating it to blue up to a low red dependent on thickness is all that is needed............it may not fully anneal the metal (a matter of heating to critical and then cooling SLOWLY, but it will usually "relax" it......

[rich pierce]

Any farm boy knows you can even work harden soft steel "baling wire" by bending it into a tight loop, yanking it straight, repeating this rapidly till the wire breaks right were you want it to. Even what we do when we don't have the right tools can teach us something!  But of course alloys of different hardness will take more or less "work hardening" to get to the stage of cracking then failing.

[D. Taylor Sapergia]

When I was a lad, I collected a runner from a stone boat that was rotting in the bush near it's last pass on a field.  I don't know if it is steel or iron - likely the latter.  Anyway, I hammer out a lance point cold on my dad's anvil and found I had the devil of a time filing the edges.  I also found cracks in the edge from work hardening.  These fissures had no affect on the lance's strength.  My buddy Shane and I used to throw the lance from as far away as we could, into a 4' cottonwood round, when I lived in Squamish BC back in the 70's.  It didn't even bend, let alone break.  This was my first intro to forging metal, and I had no fire.  Still have the lance.

[George F.]

I can see now, that making this hinge is going to be an adventure. Good thing I ordered a 12"x24" sheet. Plenty of room for mistakes and that good ole learning curve.   ...Geo.

[David Rase]

With all due respect to David it is not carbon alone that creates work hardening in steel - other elements, especially manganese contribute to work hardening and or fatigue - two different things when working with iron/steel. 1008 or any other mild steel can and often will work harden/fatigue if cold hammered on long enough or it's bent/flexed. I've learned that to my regret over the last beaucoups years of pounding iron. While one can get away with it IMO why take the chance" - heating it up is so easy and simple, especially since heating it to blue up to a low red dependent on thickness is all that is needed............it may not fully anneal the metal (a matter of heating to critical and then cooling SLOWLY, but it will usually "relax" it......

[/quote]

Chuck,  I agree, you can over pound a piece of steel and cause it to fatique.  Heating up the steel could be a good thing, depending on your proficiency at whitesmithing.  Just like it takes more heats for a less experienced blacksmith to forge the same identical part then a skilled one, if you fumble around too much cold forming a piece of steel you could ruin it also.  Thanks for the comment Chuck.
DMR 

[Kentucky Jeff]

When I was a lad, I collected a runner from a stone boat that was rotting in the bush near it's last pass on a field.  I don't know if it is steel or iron - likely the latter.  Anyway, I hammer out a lance point cold on my dad's anvil and found I had the devil of a time filing the edges.  I also found cracks in the edge from work hardening.  These fissures had no affect on the lance's strength.  My buddy Shane and I used to throw the lance from as far away as we could, into a 4' cottonwood round, when I lived in Squamish BC back in the 70's.  It didn't even bend, let alone break.  This was my first intro to forging metal, and I had no fire.  Still have the lance.

You were a creative little heathen weren't you?

[T*O*F]

George,
In the future, instead of going thru the hassle of mail order, give your local Body Shop and Paint store supplier a call.  They have steel patch panels and also usually stock 3' x3' sheet metal.

If you are really industrious, find a pre-70's car or truck and cut yourself a hunk.  While you are at it, look for generator and AC brackets for triggers/plates, etc.  Often the cost is nil.

[Habu]

If you are going to use TOF's salvage approach, the best sources for (fairly) flat and (relatively) unrusted metal tend to be the roof of the car, or the trunk lid.  I use an old bayonet and a hammer to cut the sheet from the car.  It used to be easy to find old junkers parked out on fencelines as they weren't worth the cost to haul them to the salvage yard--the recent surge in scrap metal prices has really reduced this availability. 

Watch out for bees.  And hornets.  And skunks. 

[George F.]

Sorry I'm not that industrious, I will do some things, but going to a junk yard, and salvaging metal, when all I have to do is call.  true it is more money, but less work, and I get it the next day, thanks anyway.  ...Geo.