- Joined
- Oct 17, 2010
- Messages
- 2,424
I highly recommend, even if you're a competent machine builder or fabricator, to everyone; buy your first hammer, and buy one that's "factory" made.
Every type of hammer, be it mechanical, pneumatic utility, or pneumatic self contained, have design aspects, that while not complicated, are difficult to wrap your head around, typically, for a while, until you've used them enough for your subconscious brain to compute their relation to the actual relationships of the running of the machine, and it's output.
In the case of pneumatic hammer controls, they can seem much simpler than they are, and the finite range of proper function, requires understanding it's nuance. Even having half an inch of extra movement in one item, can cause it to simply not reciprocate.
Also, when considering the "work" of each type of machine, it's not a simple relationship. All presses and hammers aren't created equal, and one can do significantly more work in a certain range of thickness, than another. A 75lb hammer may only be able to barely move a piece of 4" thick square stock, and take half a dozen heats to reduce the thickness to the point of starting to be efficient, where as a 25ton press can reduce it to half it's thickness in a heat. However, below a certain point, the press hardly moves it, and the hammer does significantly faster, the press may have also deformed the work significantly worse in the center of the billet while reducing that much thickness that quickly.
On the other hand, a very fast single stage press will be much more efficient, and capable of going to significantly better thinness, however, requires lots of HP, 10hp being roughly the minimum for efficient work.
The clay spencer hammer IMO is a great design for general small forging. it'll forge any size knife or blade (sword whatever) that could ever reasonably be wielded by a human, and great for doing general small damascus billets, big enough to make those blades. They won't however stand up to serious damascus work, but would be a fine complement to a dual stage press, for doing medium sized billets, and compensating for the way the press moves metal, once you get down to 1" or below thickness.
It's a great hammer to use for most of your work, while you decide if you need another bigger hammer for pounding billets.
Thing is, most standard patterns, especially the ones oriented, on the outsides of the bar, don't have much benefit from making massive billets, as the loss is somewhat minimal and standard. i.e. grind the outside to get past the scale, cut the ends off, and restack. On mosaic and bar end patterns however, the losses depending on the number of restacks can be up to 70%+ on complicated patterns, where the larger the billet is, the more you can mitigate loss, because a certain percentage of each restack is going to be lost. It's the same components as standard patterns, but exacerbated by having to grind deeper, restack more often, and in more complicated ways, plus the movement of the hammer vs press of the core and outside of the billet, becomes more critical, if you're attempting to control the pattern manipulation/distortion.
So it ultimately depends on what you end up doing, and needing to accomplish that. In a perfect world, we'd all have 2 of everything for ultimately utility, but I'd encourage everyone to just get started where they can, and learn the limitations of that equipment and process, then move on. Unfortunately, what typically happens is; someone gets something, feels obligated to "own it", and goes around telling everyone whatever they have is what everyone else needs, because they have it, and it's great. Or the opposite.
Regardless, building a press, and a tire hammer, or acquiring one or both, will get you a good serious start with damascus. On the other hand, having just a press, wont help you much forging blades, unless all you make are monster sized sharpened crowbars. You can however, forge to your heart's content, and make all sorts of nice patterns in the sizes needed for blade work, and bigger, with just a tire hammer.
[/QUOTE]