Power hammer test

[mike-hr]

After reading and responding to Yesteryears thread on hammer performance, I feel kind of bad posting my opinion, because that's all it is... I did some thinking and came up with a test where we can all post out results, and maybe get a better idea of the hammers out there.
I took 8 inches of 1 inch mild steel square, marked each end at 2 inches. Use flat dies. Heat to near welding, put the 2 inch mark on the near edge of the dies, and hit 5 times real hard. Heat the other end to near welding heat, same thing, but hit 10 times. Wire brush, cool and measure how thin each end got with dial calipers. Anyway here's my results:

Hammer: 1909-ish MacGowan and Finnigan 'Perfect', 80# mechanical
5 hits: .825/inch
10 hits: .630/inch

Please try this and lets see what happens,
Mike

[steveh]

great idea Mike,makes me want my new hammer even more!

[brucegodlesky]

Mike, that's as straight forward a test as there is . [i]'l try it with my Fairbanks A. Thanks bruce

[Jose Gomez]

Mike-hr, I sure appreciate the fact that you took the time to reflect on the difference between opinion and measurable results. And again I appreciate the fact that you found a reasonable way to measure a hammers general performance. I performed the test using 8" of 1" mild steel square heated to near welding heat and then struck 2" of the end using flat dies, as instructed, on both the KA-75 and the Big Blu-BluMax 155 and here is what I got.

KA-75 with 175 PSI supply pressure
starting measure 0.995
5 hits 0.773"
10 hits 0.565

Blu Max 155 with 175 PSI supply pressure
starting measure 0.995
5 hits 0.705"
10 hits 0.475"

I listed the starting thickness in order to help eliminate any variation in original thickness, and air supply pressure because it has a measurable effect on utility hammer performance. I think your spot on with this test and that if other people participate then we will be able to build up a real world performance database that will help a lot of smiths compare these machines. I am really interested in seeing other Smith's results!! Thanks!

[John N]

This is intersting, but has some limitations. It does not take into account 'controllability' , or the blow rate (bpm) of the hammer which has a significant effect on the work that can be done in one heat.

However, full power is a performance measurement, so I will run the tests on the 15kg, 25kg and 40 kg Anyang hammers, as and when I get chance (I sell them in the UK, so if someone wants to do it independently let me know)

I didn't realize that folks run their hammers at 175 PSI , over 100 PSI in the shop lines and I start to get nervey !!

[Jose Gomez]

I actually made a mistake. I supply the Big Blu with full tank pressure (175 PSI) through a 1" 200 PSI rated jack hammer air hose, but the pressure is knocked down to 150 PSI by the regulator, filter, oiler on the hammer. The KA is running on 175PSI though. I had also thought about the blows per minute, and hammer controll issues, as far as BPM Big Blu claims 0-225 on the 155, and on the KA it depends on how fast you are with your foot, but I would guess that it would be hard to even keep it at 180 BPM. As far as controll.. I don't really know that we can devise a test to measure controll because that all really depends on the operator expierience, condition of the machine, temperature of the machine, etc. I think Mike-hr came up with a great full power test, but as for controll, I am willing to accept the educated opinion of other Power Hamer operators. I know that I have no problems drawing 1/4" stock to a fine point with any of my hammers, or delivering a single light tap, or full force blow, which is a little tricky with the mechanical hammers but a breeze with the air hammers (pun intended!!)

[Hofi]

JOSE,
Can u give me the no of BPM and the daylight between the dies when making the test.
This data is very importent to comper and avaluate hammers.
And pl give me the one while u made the test and not the one that is given in the ''book''
thank U in advance
Hofi

[Jose Gomez]

Mr. Hofi

I went to the forge and measured the BPM from the Hammer and was supprized to find that it is opperating at 240 blows per minute. Also, when I performed the test I had the stroke set at nearly 9 inches, which leaves the dies about 6 inches apart when the hammer is at rest. Let me know If you would like any more information or would like for me to perform any other tests.

[Hofi]

Sorry jose but I want to understand it more clear.
the actuel day light between the upperpart of the bottom die and the bottom part of the upper die were 6 or 9 '' when forging ? or in another words -what was the real daylight when forging?
thanx again and sorry for the noging
hofi

[Jose Gomez]

No problem! The stroke was set right at 9 inches (the maximum for this machine). So when forging there was 9 inches between die faces.