Power hammer video, Kinyon

When Tozetre put fingers to keys it was 7/11/08 8:38 AM...


Having just gone back to that wiki page of formulae it looks like we want to be talking about Kinetic Energy, Work, and Power
(ignoring gravitational potential energy) KE = 1/2 x m x v^2 W = /_\KE (trying to make a 'delta') P(avg) = Work / /_\Time
So, getting the hammer going twice as fast does quadruple the Kinetic Energy of the blow, which quadruples Work and approximately quadruples Power (I'm sure contact Time increases slightly for a heavier blow. How much? no clue).

If it doesn't bounce, that means all the energy has left the hammer and gone into the piece (for practical values of 'all'). It it bounces, it's carrying some energy away with it.
The colder the work, the more the hammer bounces, the less energy imparted to the work, the less it is deformed. Hmmm...
--

Carl West
http://prospecthillforge.com : The Blacksmithing Classroom
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Tozetre wrote:

Yeah, I wish this was the same for air pressure.
I bought a Whisper Momma and it basically cost me $1500 landed :-( The forge only got hot enough to forge weld when I adjusted it, by adding an extra fire brick base (effectively reducing the size of the fire box.
Apparently this has to do with the altitude where I live (although I can't fathom why), but others with the Whisper Momma swear that it's the best thing since sliced bread.
About a month later I figured out that making a better furnace was a piece of piss. I still have the whisper momma, and when the lining wears out I will "fix" it :-)
Regards Charles
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Ah. After all is said and done, it's 1/2 MV^2.
Pete Stanaitis
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Blow me down, so it is. My apologies for claiming otherwise!
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Just got them thank you Pete :-) Just what I was thinking of, except now I don't have to figure it out for myself :-)
Thanks again regards Charles
spaco wrote:

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Chilla wrote:

This is probably too obvious, but no power hammer should be running directly off the compressor any way, so why not put in a larger storage tank?
I ran my bull hammer for a short while off of one of those little compressors that roofers use and a larger tank. It was very hard on the little compressor as they have short duty cycles, but the hammer didn't care at all.
For the small one person shop there is usually enough down time between heats for the smaller compressor to refill the tank.
I have since gone to a big honkin' two stage, but that is because I now am set up to run other things off of air and have the potential of having more than one tool in use at a time.
For a short while I considered twinning a smaller compressor into the system and setting the switch at a higher on point than the two stage. Running the numbers it looked like the energy consumption would not have changed much. Compressing a given volume of air to a set pressure just required the same amount of energy.
I do have the smaller unit piped in as a backup at the other end of the piping, but not turned on, strictly a reservoir. This also helps alleviate possible pressure drop issues due to piping size, if I fire up too many pieces of equipment at the far end of the piping.
Mike Graf
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