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Judson, I don't understand.  Help me out a little bit.

 

Rich, no it won't supplant what I now do.  It is a research project with much left to learn.  Ken Zitur has apparently succeeeded in eliminating the dump valves on his rebop[ of a Bull hammer according to his post today.  That is the carrot in front of this old donkey's eyes.

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Continuing, Ric, it is worth saying that Danger Dillon recently provided some info from an old Chambersburg air driven steam hammer manual and it used a traditional lever on the cam wiper and a treadle on the air valve (so that a smith could use it without a "driver" helper).  My existing hammer design runs like that, perhaps even better with my stroke tuning feature, however my single blow feature does not provide the tup-follows-the-treadle provided by the 3-position spool valve (as shown in Sam's video).  When Grant Sarver mentioned in his video of his Bell steam hammer that some steam hammers did not idle very well I believe now that such hammers had fairly wide boundaries on the center position of their spool valves and I believe that the Chambersburg engineering drawing shows that spool valve to have very narrow boundaries such that stepping on the treadle would elicit reciprocation (wide boundaries lead to steam locking).  If my sense of the Chambersburg is correct, it wouldn't easily provide tup-follows-the-treadle behavior.  In that case its behavior would have been pretty much like my exisiting Octagon series of hammers.  My lever sets the air space like the Chambersburg and my treadle controls the air flow (though I use back pressure control).  In short, the exisitng Iron Kiss design is highly refined and very sweet to use.  It just doesn't do double duty as a treadle hammer.  That is what I am seeking.

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John, you may look for a hydro 4 way / 2 positions with all ports closed at the crossover (not a real third 'all ports closed' center position but perhaps enough to make the magic 'ram follows treadle' feature) , it seems they only exist in hydro catalogs but perhaps they just don't mention it in the pneu catalogs (it's perhaps less critical with air than oil)...

What I really dislike with hydro parts, the directionnal stuff I look for seems to allways end up being 3/4 ID max...

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Hey John,

My Chambersburg is now set with treadle to motion valve which does provide very precise tup follows treadle control (if the throttle isn't open to much) With to much air it will then start to cycle. If I want a fully open throttle I can keep step on the treadle just a bit to stop the movement, the ram will position about 3/4 from the top then I can give a hard thump. I think Grant was speaking of "small" steam hammers don't idle. He overcame that with a loose chain from the treadle to motion valve, which he could also access by hand (the handle on the side) Basically he could drive from the front! His hammer was hooked up with treadle to throttle with a auxiliary air line to the motion valve chest, this just raised the ram. My Niles is set up with treadle to throttle and will cycle if you start close to the bottom of stroke. If I just give it just enough air to raise the ram I have to let the ram fall to get it to start again thats where the (chain) link between the throttle and motion valve would be handy. You may be able to experiment with this idea, keep up the great work, U DA MAN  :D

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are you able to get the hammer cycling when you have the hammer set this way? In your video, your hammer looked like it was reacting like my set-up does when I have it in the treadle hammer mode, I am able to get it reciprocating

but it is a little harder to accomplish.

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To switch back and forth would be ideal. I still think Grant's hammer is as close you can get to doing both and as bout simple as you can make it happen. The smaller hammers are just going to be difficult to mellow out, especially under high pressure. A really great vid Ken, I like the high pressure testing! You going to get something hot :huh:

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Danger, I am wondering if the things I have observed  with my style of steam hammer linkage would apply to your Chambersburg in regards to single blows and reciprocating motion. I think they would as both systems are similar.  I apply pressure to the motion (directional) valve ( I use a spring) which forces the tup down and spring pressure on the treadle to lift it up which, through the linkage, forces the tup upward. What I have found is to little spring tension on the treadle and the tup will not lift all the way up. To much spring tension just makes it harder to push the treadle making precise control of the tup more difficult. Less pressure on the directional valve makes the hammer reciprocate easier with less psi and makes for a  longer hammer stroke, but makes bringing the tup down smoothly for that single blow more difficult. More pressure on the valve gives you a smoother down stroke but requires more psi, shortens the hammer stroke and also speeds up the bpm.

That's my 2 cents (which is real only worth about 0.0002 cents nowadays!!)

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Whereas I was pretty depressed last night, that is not the case now.  Today I attained reciprocation on the "steam" hammer and it is repeatable, predictable, and tunable.   Hurray! 

 

Basically I doubled the cam lift and reduced the jackshaft radius of the roller so as to increase movement of the vertical pushrod per inch of tup travel.  This took the bulk of my work day.   When reciprocating I was getting full stroke and the stroking would slow down from air pressure and cfm reduction.  By changing to another hole on the T-lever with less lift for the vertical pushrod and spool, I achieve single blow treadle hammering without reciprocation.  The T-lever's array of holes for connecting the bottom of the vertical pushrod is analogous to Ken Z's slotted lever.

 

The next stage of work is to refine all the pieces including the cam.  More rigidity is needed to eliminate lost motion.  No evaluation of reciprocation blows quality will done until I'm satisfied with the cam, levers, tie rods, and motion geometries.

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Today I did a bit more experimentation with cam lift.  To do so required that I use my plasma cutter to remove a bit of the cabinet floor for clearance, and while I was at it I removed more than necessaryso as to allow wrenching of the jack shaft levers from below.  Crude, but I'll clean up the jagged edges when I eventually tear down the machine for finishing.  I opted to re-drill the brackets for the jackshaft to move it away from the bottom of the cam.  Back together it ran as it had yesterday.  The added cam llft tried today was not of benefit.  I noticed that the lever for the springs was slipping on the jackshaft and no amount of tightening helped.  So I took a break to mull things over.  When I got back from my machine shop store I inverted the lever, tack welded it to the lever controlling the horizontal push rod, and mounted the tensioning springs below the cabinet floor.  Though temporary, this had a really good effect in that the machine would stay in tune during longer duration reciprocation tests.  The cfm inflow throttling via a hand operated simple ball valve worked better than yesterday.  For the time being, I suspect I'll keep the treadle acting as a motion control and keep the air flow hand operated.

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Today I tried a special inflow hand valve with more linearity than a ball valve.  Virtually no improvement, so I went back to the standard ball valve.  For the reciprocating mode I set the valve wide open and I control speed substantially with the air pressure regulator.  I find this quite acceptable at this time.  I did a couple of hot rr spikes and found the hammering adequate.  Still not in the same league as my utility hammer, but over time I will learn to make  the machhine a better pounder.  Where air in-flow throttling makes sense and works is when the machine is set for treadle hammer behavior.  But a fancy valve is not needed for that.  Therefore, I am comfortable with the treadle controlling the motion linkage and the air flow being under hand control and basically held constant during a forging session.  It is possible to lift the treadle to achieve lighter blows so that precision hammering is possible.  As I've gotten the linkages improved, especially over the past several days, i've become more confidant about what is going on.  I have a shortening to-do list of refinements.   I'm ending my week in a very good mood.

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