Push-Pull Tuning Question/Problem

Instruments, mechanical issues, copedents, techniques, etc.

Moderator: Shoshanah Marohn

Post Reply
User avatar
Cliff Kane
Posts: 1932
Joined: 10 Dec 1999 1:01 am
Location: the late great golden state
Contact:

Push-Pull Tuning Question/Problem

Post by Cliff Kane »

I'm having a tuning issue with my p/p that I can't figure out, and I'm hoping that someone can help me out. I just put some new strings on yesterday, and I'm now tuning it up to Jeff Newman's tuning chart for E9.

Here's what's happening: I am tuning the 5th string B, and the pedal A and pedal C 5th string raise to C#. I am trying to get both pedals A and C to raise the 5th string B to C# at 436Hz (per Jeff Newman). What happens is if I tune pedal A to C# at 436, pedal C will be C# at 434: this 2Hz discrepency between pedals A and C for raising the 5th string seems to be consistent.

Here is what I have tried: I have tuned the changer finger by pushing it by hand against its stop so that the raise is at 436Hz; I have checked the string at the keyhead with pedal A to C# at 436 and it's in tune, then released the pedal and tuned the string open with the lower tuning screw to B at 439.5; after this normal tuning procedure, the 5th string is at an open B at 439.5, with pedal A it is C# at 436, and with pedal C it is C# at 434. This is the problem.

I have turned the guitar over and looked at the way the pull rod is working: I can see that both pedals A and C are pulling the raise rod for the full travel; in other words, when pedals A or C are pushed the finger is pulled to its full stop, and when pedals A or C are released the finger returns to rest against the lower tuning screw. I have also tried sliding the collar (it rests behind a spring) that the pedal C bell crank pushes against to pull the rod, so that pedal C engages sooner, but that didn't make a difference.

So, eveything looks okay to me (but I'm am pretty new to the p/p mechanics), and I'm pretty sure that I am tuning it correctly. What I'm a missing? What am I doing wrong? Or, is what I'm noticing--that pedal C drops the 5th string about 2Hz lower than pedal A drops it--a symptom of cabinet drop?

Any advice or insight will be very helpful and grately appreciated!

Cliff<font size="1" color="#8e236b"><p align="center">[This message was edited by Cliff Kane on 18 August 2006 at 07:43 PM.]</p></FONT>
User avatar
basilh
Posts: 7694
Joined: 26 May 1999 12:01 am
Location: United Kingdom
Contact:

Post by basilh »

A very long and detailed explanation, but sadly in my opinion a short answer.. Cabinet drop.
I REALY wish I could help, maybe I'm wrong (I hope so, but fear I'm not).
Basil

------------------
Image
User avatar
Cliff Kane
Posts: 1932
Joined: 10 Dec 1999 1:01 am
Location: the late great golden state
Contact:

Post by Cliff Kane »

Thanks, Basil. Sorry for the long question, but I know that the process and mechanics of p/p's is sort of elaborate, so my intent was to let people know exactly how I am tuning it, etc., to not have people feel the need to post the tuning procedures, etc., that get rehashed in these p/p threads.

Perhaps it is that darned cabinet drop, as you say.

Thanks for your help.<font size="1" color="#8e236b"><p align="center">[This message was edited by Cliff Kane on 18 August 2006 at 10:26 PM.]</p></FONT>
User avatar
richard burton
Posts: 3846
Joined: 23 Jan 2001 1:01 am
Location: Britain

Post by richard burton »

An easy way to check if the problem is cabinet drop is to detune the fourth string until it is slack, and then check string five with the C pedal pressed.
Paul Redmond
Posts: 1153
Joined: 3 Apr 2006 12:01 am
Location: Illinois, USA

Post by Paul Redmond »

Add #8-32 screws to tie down the tuning head casting better to the cabinet. I discovered this when machining some keyheads for Charlie Ward, a master p/p builder. The standard keyheads only have 2 screws at the outer end and 2 under the roller nut. That's not sufficient to hold that long casting down tight to the cabinet. I asked Charlie at the time if I could add screws to the middle of the castings. He said OK, I did, and 2/3 of the so-called cabinet drop evaporated. It's well worth the time spent. Charlie can tell you more about that at 1(828)684-6771. It works!!
PRR
User avatar
Steve Alonzo Walker
Posts: 471
Joined: 6 Aug 2000 12:01 am
Location: Spartanburg,S.C. USA (deceased)

Post by Steve Alonzo Walker »

Check the set screw (if you have them) where the pedal rods attach and be sure it is not stopping the pedal travel before the finger reaches the guitar body. Just a thought.
User avatar
Garry Vanderlinde
Posts: 1500
Joined: 14 Nov 2002 1:01 am
Location: CA

Post by Garry Vanderlinde »

If you haven't seen this P/P Emmons set up guide, check it out;
http://www.melmusic.com/laceyj/guide.html

Scroll down to the "Common Set Up Problems" and see if any of the fixes will work for you.
User avatar
Rainer Hackstaette
Posts: 442
Joined: 10 Jun 2001 12:01 am
Location: Bohmte, Germany
Contact:

Post by Rainer Hackstaette »

Cliff,

1. Check the shock (compression) spring between the bellcrank swivel and the rod collar. It should move freely when the pedal is not activated (at least a millimeter or so) it should not be compressed when not activated.

2. If you tune the C-pedal 5th raise at the keyhead to 436 Hz, how far does the A-pedal raise the 5th string? Higher than 436?
If so, then the C-pedal doesn't have enough travel and does not bring the raise finger against the body. It will be just a hair, so it may be hard to see, if you turn the guitar over. If that is the case, lengthen the throw by turning the pedal stop screw counterclockwise.

BTW: I don't see how it could be cabinet drop. Cabinet drop usually means that a string that is not pulled goes flat when a pedal/lever raises other strings; e.g. 4th string goes flat with A+B pedals, 6th string goes flat with A pedal or A+F. If a pulled string doesn't reach its pitch then there's not enough travel or something is binding.

Getting the A and C pedal pulls to reach the same pitch is a bear on a P/P. You could install a halftone tuner (like the one on your F-lever) on either the A or C pedal 5th string bellcrank swivel. It makes syncronizing the C#-tuning a little easier. But there has to be sufficient travel for both pulls, nonetheless. (I know this is cheating a little, but I' lazy. Image )

Rainer




------------------
<FONT SIZE=1 COLOR="#0000FF">Remington, Sierra, Emmons PP, Fender Artist, Sho~Bud</FONT>

User avatar
richard burton
Posts: 3846
Joined: 23 Jan 2001 1:01 am
Location: Britain

Post by richard burton »

Pedal C is raising 4+5.

Both fingers should be touching the body when pedal C is pressed.

Take 4 out of the equation.

Press pedal C.

Finger 5 will be touching the body, and the note will be fractionally higher than before, due to less cabinet drop. (because string 4 is not raised)
User avatar
Cliff Kane
Posts: 1932
Joined: 10 Dec 1999 1:01 am
Location: the late great golden state
Contact:

Post by Cliff Kane »

I would like to say thanks! to everyone for your excellent and generous help.
Richard: I tried slackening the tension on string 4, and that made no difference.
Rainer: I followed your advice, I checked the shock spring, made sure there is some slack between the spring and the collar (when not engaged) and that pedal C is engaging the raise for strings 4 and 5 at the same time (all this was fine and had been set-up pretty well), and then I backed of the pedal stop screw to add travel to pedal C......still made no difference.

I have tried something else that I did not try before:
While holding the finger by hand against the stop and tuning the C# to 436, when I push pedal A (while still holding the finger by hand against the stop) the note stays at 436. However, when I do this with pedal C (still holding the finger by hand against the stop) the note does change to somewhere between 434/435Hz. I guess this indicates that this is caused by cabinet drop, or some force introduced to the undercarrage mechanics by the engagement of pedal C.

Shheesh! I feel like I'm working on a Jag! I can see why people love their all-pull guitars! This thing sounds great, though!

Thanks again for the good help and advice. I'm learning a lot from you guys. <font size="1" color="#8e236b"><p align="center">[This message was edited by Cliff Kane on 19 August 2006 at 12:00 PM.]</p></FONT>
User avatar
richard burton
Posts: 3846
Joined: 23 Jan 2001 1:01 am
Location: Britain

Post by richard burton »

I'll get me coat...... Image
User avatar
Cliff Kane
Posts: 1932
Joined: 10 Dec 1999 1:01 am
Location: the late great golden state
Contact:

Post by Cliff Kane »

Richard, thanks, I would not have thought about the relation between the C pedal and the 4th and 5th strings. I learned something from your idea, and that in itself is a real benefit.

I guess this is why there are compensators??? I think I am beginning to appreciate these things. I don't have this problem with my LDG.
User avatar
Cliff Kane
Posts: 1932
Joined: 10 Dec 1999 1:01 am
Location: the late great golden state
Contact:

Post by Cliff Kane »

Check it out: about of y'all are across the pond! What a cool World Wide forum we've got!
Are there a lot of p/p player in the UK and Europe? Seems like any pedal steel might be a rare thing, let alone a p/p.

Cheers!
User avatar
basilh
Posts: 7694
Joined: 26 May 1999 12:01 am
Location: United Kingdom
Contact:

Post by basilh »

Cliff, I have 2 P/P D-10s
one of which I've been playing since 1971.
Both of them 1970 'Fatbacks'
see :-
1340d

AND :-
1415d


Image


------------------
Image

<font size="1" color="#8e236b"><p align="center">[This message was edited by basilh on 19 August 2006 at 06:58 PM.]</p></FONT>
Jim Palenscar
Posts: 5857
Joined: 4 Aug 1998 11:00 pm
Location: Oceanside, Calif, USA
Contact:

Post by Jim Palenscar »

An interesting thing to do is to watch the tuning on a note while engaging the actual pedal that causes it to detune then actuate the same pedal's change by moving the bellcrank instead of actually pushing the pedal- commonly there is a big difference in the amount of measurable detuning lending credence to a truly flexing or "dropping" cabinet~
User avatar
Cliff Kane
Posts: 1932
Joined: 10 Dec 1999 1:01 am
Location: the late great golden state
Contact:

Post by Cliff Kane »

Basil,
nice! are those home made knee levers, and what are those brass and silver barrel thingies? They look like they might be some sort of half-stop? What's the story on the single neck....do you play it out, vice grip and all?
User avatar
richard burton
Posts: 3846
Joined: 23 Jan 2001 1:01 am
Location: Britain

Post by richard burton »

I don't like the shock springs on a PP, so, to aid with the accurate setting of the pull-rod collars, I use home-made half tuners on all pedals, and the F lever.

They vary in design as I was experimenting with different ideas Image

Image
Image
Image
Image

User avatar
Cliff Kane
Posts: 1932
Joined: 10 Dec 1999 1:01 am
Location: the late great golden state
Contact:

Post by Cliff Kane »

Man, I am impressed with you guys. I wish I had the know-how and talent to do that kind of work. I have a hard time just wrapping my brain around how these things work!
Post Reply