[TheForge] heavy metal math/c frame press

[John Husvar]

Grover Richardson wrote:
> Agreed.  But still, a stream of liquid (or gas) can cut you in half (under
> certain circumstances, and 10 ms of stream can still push oil under the
> skin).  Remember back when they did injections in the early 70s with
> pressure, no needle.  I'm not trying to be paranoid, however if someone is
> taking on a system with which full knowledge is not known (which may or may
> not be the case here), caution is advised.  I regularly get called to fix
> things with little or no documentation.  It gets interesting sometimes<G>.

Agreed. It's always a good idea to learn as much as possible about 
anything one might attempt home-building, especially known failure modes 
and their prevention/protection.

Yep, I sure do remember those needleless injectors, and walking between 
two pairs of Navy Corpsmen who seemed to take a hideous delight in their 
jobs.:) Was earlier than 70s though -- 1965 for me, Parris Island, SC.

> 
> Oh, it's just a current sample of 100 MA, but they forget to mention that if
> the resistor breaks, then the full 35 kV is across the test equipment.  I
> saw that one coming, and the result of ALL the components blown off the
> circuit board, only little wires standing up, like a bad grass cut.
> 
> I also have seen the result where they took schedule 80 2' diameter pipes,
> and piped the output of 2 50 hp blowers into one pipe, and then shut the
> pipe off<G>.  

Lesee -- Pressure X Area == ? X blah,blah,blah, == stress at extreme 
outer fiber ==

Darn, that was a long time ago! Too long it appears and I ain' agonna go 
dig out them books!

Not enough info, but if you're talking about two 50 HP compressors' 
output into 24" diameter pipe of much length -- could be a big Oops!
KaBOOM! :)

If not compressors, what kind of blowers? Usually fans or squirrelcage 
blowers will just stop moving air when the pressures on both sides 
equalize. Seems like they'd equalize way before reaching the yield point 
of the pipe material.

Just curious, not arguing.

> 
> We all can say, well that is just an isolated incident.  But then, as I
> remember, folks tend to put shields up on their little giants.  Seems that
> the isolated incidents of springs breaking is feared<G>.

Just good sense. It's a known failure mode and somebody found a way to 
prevent it or protect against its hazards.

> 
> By the way, if you have a 48X or faster cd player in your computer, don't
> sit with your eyes level with the player.  I had a bad disc in mine, it
> broke while spinning, and exploded, literally, taking the front off the
> player in the computer.  I have pictures.  I did NOT see that one coming<G>.
> 

I've heard of that, but thought it might be an urban legend. Guess not. :)


-- 
Life is not a journey to the grave with the intention of
arriving safely in one pretty and well-preserved piece.
One should rather skid in broadside, thoroughly used up,
totally worn out, and loudly proclaiming -- "WOW!  WHAT A RIDE!"