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Hey everyone, since this is my first post let me introduce myself. My name is Daniel and I live in the Willamette valley in Oregon (in case anyone needs a shop hand). I made this account when I was still a complete novice and trying to make tongs out of railroad spikes and using channel locks as my main tongs. Also when I was collecting cast iron window weights thinking that I was going to forge them into something. lol anyway let me get into the meat and potatoes of this post... I've been searching all over the web looking for different designs of treadle hammers because I want to build one to suit my needs. Compared to almost everything else blacksmithing, there is very little data on the good 'ol human powered beast. However the discussion is always centered around one existing design vs. another (Grade-Marx vs. Clay Spencer's design, the fabled Grasshopper, etc. Swing arm vs in-line etc.) Nobody really talks specifically about WHY these designs are good or bad beyond the basics: Anvil, hammer and spring weight, materials, build complexity... But one thing is ALWAYS ignored... GEAR RATIO!! First let me mention that I have never used a power hammer OR a treadle hammer. In videos, though, I am not at all impressed with the power of Clay Spencer's design. It's a 1-1 gear ratio with the pivot in the very center of the bar, and the drive linkage at the very end of the bar. It appears it hits NO harder than your foot can stamp the lever. The older gentleman with the Grade-Marx hammer, however, had some oomph behind it. I'm sure you've noticed how far back on the spring his linkage is set up. However I did notice when he went to faster hits, it seemed to lose a lot of power. The Clay Spencer seemed to really shine for repetitive hits. I'm also thinking a lot about drive systems. Levers and springs? Pulleys and springs? Counterweights? (I've read people don't like counterweight THs much though) I could make a treadle hammer with tons of pulleys, heavy duty rope, and a coil spring from a car, and it would be a wonderfully adventurous press. The foot pedal would have to travel so far that I'd need to climb a ladder and ride it down in order for the hammer to move a few inches with a tremendous amount of force. 9-1 ratio = 100 lbs on the foot pedal with 9X the travel distance = 9x the force on the hammer end with 1/9th the travel distance. And I also understand that Force is = to mass (weight) x acceleration. (I'm not actually this smart, my dad is a mathematician and i'm always bothering him with questions) So with this concept in mind I'm thinking I want the hammer to travel really far and the foot pedal to be very hard to press. But then there's a balance I need to find because I'm a hermit without power in my shop and really want to use this thing to draw bigger stock into smaller stock. (eyes the sway bar and coil springs on a junkyard truck) That being said, I also like doing decorative work and do love the idea of controllability while using tools. What are your thoughts? I really want to build this thing and I want it to be exactly what I need. Please help