[TheForge] Sodium filled valves

[Andrew Vida]

Ron Childers wrote:
> 
> A friend who recently joined our group was given a bucket of engine valves
> and wants to "make things out of them". He has no idea what kind of vehicles
> the valves came from.
> 
> The old air cooled VW and Chevrolet valves are ok, but not knowing, I told
> him not to do anything with them 'til I consulted my panel of experts. I
> have heard forging or cutting the sodium-filled valves could be hazardous.
> 
> 1. Is there a way to tell for certain which ones contain sodium?

	Sodium is used almost exclusively in larger engines, most often 
air-cooled.  Look for a convex face - a strong clue.  Also, look for a 
hardened stem end that shows a clear demarcation line between it and the 
rest of the stem.  This is where the sodium was put into the valve and 
the end brazed on.  Chances are you will find zero evidence of a braze 
line, tolerances being what they need to be there.

	I used to have many of these from old P&W and Franklin radial aero-engines.
> 
> 2. What happens if they are heated in a forge?

	Nothing at first.  With heat, the sodium melts.  When you hit it  and 
the valve ruptures, you will be splattered with molten and WILDLY 
burning pure sodium metal.  You will be severely injured and maimed, if 
not killed outright.  Therefore DO NOT MESS WITH THEM.  Do not even open 
them up because the sodium will begin to burn almost immediately on 
contact with O2.  IIRC, they are either under vacuum or partial vacuum, 
filled with a gas such as argon or helium.  Once ablaze, you will 
probably instinctively attempt to put it out with water and will them be 
in for yet another surprise most unpleasant.

	In the old piston-engined airliner days an engine fire requiring  a 
ditch into water was one of a pilot's nightmare's because of the worry 
of breached valves meeting sea water.  All that burning magnesium didn't 
make things any better, either.
> 
> 3. Cut with a chop saw? 

	Only if you do not value your life.
> 
> 4. Does anyone have any first hand knowledge of misadventures involving
> sodium-filled valves?

	Been there.  Done that.  'nuff said.
> 
> I heard in aircraft mechanics school that many engines do have sodium-filled
> valves and that it's a bad idea to try to make punches or drifts out of
> them.

	You heard right.