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Making a Power Hammer


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I am beginning the search for parts for a home made power hammer. I will base my plans on the Anvilfire X2 mechanism, although I am making the tower out of I-beam (and the dies at a 45 degree angle) instead of having a hole pass through the tower.

X2_360.jpg

I like the design because it has the same whipping motion as a dupont mechanism, but there is no "spring of death" that can pop out and kill you in the face.

For the base I have found some truck spring billets. They are 41 3/4" long, 70 lbs each, and are 4" by 1 1/4". If I buy 16 of them, I can have a 9" by 9" square anvil that is 1120 lbs. It will probably need to be shortened so it might be around 980 lbs instead. I was considering just buying 4 and having a 5" by 4" anvil, so about 280 lbs, but If I follow the general 10:1 anvil-to-ram ratio, I would only have a 28 lb ram. I don't know if that would be enough for me to make damascus billets or work on larger ironwork. I have done a little research on the whole anvil-ram ratio deal, and it seems that there is no consensus among smiths.

To me, the logical explanation of the anvil and ram relationship seems to be more about rigidity and the base. Here are the general rules that make sense to me:

  1. The anvil has to be completely solid all the way to the concrete base.
  2. The anvil has to be rigid (thick) enough so that the force of the ram doesn't want to bend the anvil so the side, like how steel always wants to curve one way when upsetting. 
  3. The concrete base needs to have good contact with the bottom of the anvil, this way the base acts as an extension of the anvil, allowing the anvil to behave like it is heavier than it really is.

Should I go with the 280 lb or do the 1120 lb anvil? The cost for the 280 would be $140 and the 1120 lb would be $560. it seems pretty expensive to get the 1120, but it is one of the major components of the hammer, and one of the most expensive. It's a lot cheaper than getting a 100# Anyang, LG, or Blu, that's for sure. 

 

There is an 81" long 8" square I-beam at the scrap yard, too, which would be a good tower.

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You want the anvil heavy, but you'd prefer it to be solid.  It doesn't need to be hardenable, though, except for the dies.  OTOH, the TUP can be built up from plates,  it doesn't  appear to matter.

In anvilfire 1.0 they used shock absorbers, which actually hurt their performance.  What does this design use for spring?

Has anyone considered using airbags, like from a heavy truck?  Some of the Bradley and Fairbanks hammers used them.

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There are a couple of leaf springs on each side. When the ram is hanging on its lowest point, the arms want to go down due to the weight of the ram, but the springs create an outwards pressure that keeps the arms at a more obtuse angle. This creates a similar springyness that the dupont mechanism has.

http://www.anvilfire.com/AnvilCAM-II/index.php?video=x1-test1

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I see it now.  There is a Bradley that used that design.  I used a "U" shaped stack of leaf springs and grade 8 bolts for toggles.  It's been running since 2000 without any trouble.  Your design is nice and compact though.

 

Geoff

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