Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Technical term: what is an action stack?

Dear technicians,

I've come across the term "action stack" in a number of threads here. Mr Reblitz doesn't mention it in his book, so I'm wondering what is meant exactly by the stack. I gather it only applies to grands. Can you enlighten me?

I'm not a tech.
The action stack is the action frame (brackets and rails) that the actual action parts are hung as in the hammers,shanks,flanges,wippens,let off buttons.

It (action stack) screws down on to the key frame on top of the keys /capstans themselves.
I've managed to make it sound confusing than ever.

You've described it quite well, actually.

Got it, thanks!

Anyone have any idea when and how the term came into being? Was it a specific company that coined it, or did techs just start to refer to it as the "action stack" at some point in time?

I think it's a useful term that differentiates the stack,from the keys and keyframe when describing what part of the grand action is being referred to. One of the two main components of the grand action. Add to those descriptive terms the use of "Back action" for the damper umderlever system in a grand.

Been in the business about 30 years and have always heard the term.

There is the similar term "valve stack" used in hydraulics. A number of valve bodies are stacked up on studs and bolted together to work as a combined unit such as pressure relief and flow control. Sort of what all the parts in the "action stack" do: letoff, checking, repetition, etc.

I have always heard the term action rack. Never heard of the action stack until reading modern literature on the subject of piano repair.

action stack - "achun stak" - One or more piano actions stacked one on top of the other.

Source - Jenson Dictionary of piano technology, an unpublished unheralded compendium of technical terms related to the piano industry.

In the world of player pianos, the upper part of the player, that which has the primary and secondary valves, the pouch board, and the 86 playing pneumatics is known as the player STACK. Mr. Reblitz, who is a well respected player expert and refurbisher was probably refering to the player and not the piano action or frame.

That's what I think too Jim...

RPD

David:
Haha, good one. Given the nature of your answer, I'm not really surprised that your Dickshenairy of Pianner Tecknollogy has neither been heralded nor published...

Jim:
You misread my initial posting. I wrote that Mr Reblitz does not mention the term "action stack" in his book (Piano Servicing, Tuning, and Rebuilding"), but that I saw it on these forums. It was specifically used as "action stack", not "player stack". The context was normally the repair and regulation of grand actions.

Suppose we could say..... "MAN! That action is really stacked(!!)" and get away with it?

Well, Jerry, when I read the responses, I felt that we have jacks of all trades, knuckling their way into this thread, trying to hammer us with good puns, voicing and repeating funny ideas, stringing the jokes one after the other, unbridled, trying to be teh center of attention, not beating around the bushing, until in the end, given the lack of regulation, the whole thing begins to sound off-key and just derails the thread.

And all just because everyone wants to catcher piece of the action.

Enjoy the weekend!

I think you have covered the whole scale there Mark....

Thanks Dan - I've found that if my bassic humor begins to sound tubby, I just give it an extra twist.

Now let's put a lid on this, before we crack up.

I'm threatening you with a false beat; don't make me give you a real wippen! We should soft pedal this whole topic (do I soundboard yet?).

--Cy--

Well now, this certainly has spruced things up in here. It reminds me of my dentist. With having recently had a tooth pulled, now I need a bridge and two crowns. I'm not ribbing you either. Just so long it doesn't affect my vocal chords I will remain soft spoken and mellow if you get my point.

With all things created equal, I think I'll beat my own drum and set my own temperament while I sing my own tune for a little bit here. Perhaps even in some sort of Victorian style but I'll be sure to control the tone of my voice.

Well, I do believe that it is past my bedtime. So, I think I'll go upstairs now and strut my stuff. That motion my friends, is sustained.

I'm glad this topic found such good resonance. But before Cy gives me a nose bolt, I'd better put a damper on this.

Cheers, and have a good week.