Lets talk pneumatics: I need comprehensive info on air hammers

[FieryFurnace]

Thanks for the additional info.
Purchasing any of the manufactured hammers is not an option for me right now. I can build much, much cheaper than I can buy. I have seen the KA hammer before, but I still need the option of a cycling hammer. Often, I need single hit ability, but not exclusively. My current old-style Kinyon is perfectly capable of single hit control.
Control-wise, I can live with my current Kinyon. I was just thinking of the Coleman because of the added features. However, after several suggestions, I think I will use a different control system.

I don't currently use any long punches or drifts, or other tools, under the PH. I'm thinking less about tool clearance, but more about space for the head to operate above my tooling. You put a cupping tool, a 4.5-inch billet, and a flatter between my dies, and I have an inch and a half of room for the head to cycle. Plus it doesn't have the power to upset the stock anyway.

I do like a good mechanical hammer, but they seem to need momentum to get going. Thus instead of a single power blow, you get a "tap, tap, blam" approach.

I get what you are saying about the "triggering"mechanism affecting the throw of the hammer.
The key then to having a varying hammer blow based upon how ad the treadle is compressed, is to have your triggering mechanism somehow tied into the foot peddle. Thus, as you depress the peddle more, the blow gets longer and heavier.
My current system is a manual adjustment. You have to unscrew, reposition, and retighten the trigger, thus preventing mid-heat transitioning.

[metalmangeler]

Dave you should be able to use your top flat die as your flatter thus giving you more room. The cupping tool should not need to be more than and inch deep if that. For working under a hammer to do these your punch does not need to even be as long as your stock is thick, drifts can also be very short especially if you use more than one to open up the hole. A short drift can then be held with tongs for forging the cheeks. 12 inches is  a lot of room for most projects. Now the idea of a heavier harder blow that I can really get behind I would think 60# might be to small for the stock you are using.

[FieryFurnace]

Dave you should be able to use your top flat die as your flatter thus giving you more room. The cupping tool should not need to be more than and inch deep if that. For working under a hammer to do these your punch does not need to even be as long as your stock is thick, drifts can also be very short especially if you use more than one to open up the hole. A short drift can then be held with tongs for forging the cheeks. 12 inches is a lot of room for most projects. Now the idea of a heavier harder blow that I can really get behind I would think 60# might be to small for the stock you are using.

The dies aren't large enough to cover the whole face like a flatter, but for those size hammers, my power hammer isn't powerful enough anyway.

So from the information here it seems I need to stick with 100 pounds of ram, and a 12-14 inch cylinder, with a 2.5-inch diameter, and 3/8-1/2 inch ports.