Pneumatic Pedal Mechanisms

Alan Brookes · Post by **Alan Brookes** » 10 Sep 2006 7:00 pm

I just returned from this month's meeting of the Northern California Association of Luthiers in Petaluma. One of the questions which came up in discussion is whether pneumatic mechanisms, rather than cables and/or levers, could be used on pedal steel guitars much in the way an auto brake system works. The compression of brake fluid is pretty stable, and I would think that a simplified mechanism could be made. The pedals would compress fluid, and there would be just a tube from there to the string finger mechanisms. Has anyone tried this ?

Bill Hatcher · Post by **Bill Hatcher** » 10 Sep 2006 7:35 pm

How would you disconnect the pedal board from the body with all those tubes full of brake fluid running from the body to the pedals?? The guitar does have to be packed up and moved every now and then.

All I see is a mess with break fluid everywhere and having to bleed the lines on your guitar before every session!

Per Berner · Post by **Per Berner** » 10 Sep 2006 9:32 pm

To clarify terminology, what is discussed above would be a HYDRAULIC system - pneumatics involve compressed air. That, on the other hand, could be quite interesting, adding some fun hissing and popping noises

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´75 Emmons p/p D10 8+4, ca '72 AWH Custom D10 8+3, Hybrid Zum coming soon, Peavey Nashville 1000

Jackie Anderson · Post by **Jackie Anderson** » 11 Sep 2006 3:47 am

Besides the potential mess, another drawback of hydraulics generally is less tactile feedback.

Roger Kelly · Post by **Roger Kelly** » 11 Sep 2006 5:02 am

If it ain't broke.....don't fix it. http://rube.iscool.net/

Jim Cohen · Post by **Jim Cohen** » 11 Sep 2006 5:07 am

If it ain't broke.....don't fix it

Hmmm, that sounds familiar. Was it the inventor of the slide rule, or of carbon paper, who said that?

Dick Wood · Post by **Dick Wood** » 11 Sep 2006 6:25 am

Hey Alan was the head speakers last name Goldberg by any chance?

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Cops aren't paid much so I steel at night.

Jim Bob Sedgwick · Post by **Jim Bob Sedgwick** » 11 Sep 2006 6:41 am

I think it would work very well. But you'd have to change the oil every 3000 chords.

Micky Byrne · Post by **Micky Byrne** » 11 Sep 2006 7:10 am

Hi Guys, a friend of mine over here in England called Jim Smith actually built a mechanism for what is being asked here. It even had a some bleed nipples like a car brake system has. Only draw back was the system was heavy, but the pedal action was soooo good. I don't think he continued with that project

I can just imagine a fluid leak onto someone in the audience

Micky Byrne www.mickybyrne.com

Jerry Roller · Post by **Jerry Roller** » 11 Sep 2006 7:24 am

If we can send a zillion pound spaceship into orbit and bring it back there is no question a hydraulic system could be designed to work great on a pedal steel guitar IF cost was no object. We have all sorts of products that work perfectly that are so technically advanced that this system would be considered very low tech. The crossrod could have a cam that rested against a slave cylinder plunger so the pedal bar and pedal rods could be as they are now. I bet for say $60,480.00 a D10 could be built with a great hydraulic system with great feel, precise action and a system that electronically kept tuning checked and corrected at all times. Seriously, I do believe if time is allowed to go on long enough someone will be offering a hydraulic changer system. No reason not to, as hydraulics are proven very dependable, and unlike a electical magnetic system it can be controlled precisely. A pull could be snapped suddenly or "milked". Someone should and will go for it someday.
Jerry

Jim Cohen · Post by **Jim Cohen** » 11 Sep 2006 7:33 am

Someone should and will go for it someday

Oh, you must mean Ed Packard.

chris ivey · Post by **chris ivey** » 11 Sep 2006 9:07 am

i'm thinking anti-gravity and zero point energy.....the roswell steel....not really out of the question these daze!

David Wren · Post by **David Wren** » 12 Sep 2006 8:48 am

I've often wondered why no one has made an "electronic" PSG, with electronic pitch changes activated by contact switches in the pedals. The strings would remain at the same tension.

I personaly think this would be a terrible idea, but surprised we have not seen this yet.

As far as the brake cable idea.... imagine if you had one burst, and couldn't stop the song!!!!!!

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Dave Wren
'96 Carter S12-E9/B6,7X7; NV 112; Fender Twin Custom 15 ('65 reissue); Session 500s; Hilton Pedal; Black Box www.ameechapman.com

[This message was edited by David Wren on 12 September 2006 at 09:56 AM.]

John Fabian · Post by **John Fabian** » 12 Sep 2006 9:01 am

Can you say microprocessor controlled digital pitch shifter?? I did one of these back in the earliy-mid eighties.
<div style="display:none">[This message was edited by John Fabian on 12 September 2006 at 10:02 AM.]

David Wren · Post by **David Wren** » 12 Sep 2006 10:08 am

Hey John, got any pix?

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Dave Wren
'96 Carter S12-E9/B6,7X7; NV 112; Fender Twin Custom 15 ('65 reissue); Session 500s; Hilton Pedal; Black Box
www.ameechapman.com

Ray Minich · Post by **Ray Minich** » 12 Sep 2006 10:10 am

Fluid logic with bubble memory.......
Digital in air & oil.
The first PSG to come with it's own auxiliary power unit...[This message was edited by Ray Minich on 12 September 2006 at 11:11 AM.]

Barry Blackwood · Post by **Barry Blackwood** » 12 Sep 2006 10:31 am

I'm with David, although I'm not able to dismiss the idea quite so easily until I've heard it and felt it .....

Rick Collins · Post by **Rick Collins** » 12 Sep 2006 11:02 am

The main purpose of hydraulics is to multiply mechanical advantage __ light pressure on the master cylinder to deliver great pressure to the slave cylinder.

So little pressure is needed with the pedal steel, would an hydraulic system be practical?[This message was edited by Rick Collins on 15 September 2006 at 06:14 PM.][This message was edited by Rick Collins on 15 September 2006 at 06:17 PM.]

Ron Page · Post by **Ron Page** » 12 Sep 2006 11:14 am

Can’t answer Rick’s question, but packing ‘er up ought to be an easy one to solve. Hint to inventors: Watch NASCAR some time and see if the handle doesn’t come off the hydraulic jack. The pedal rod is the actuator, not the mechanism.

On the other end I think we’d want to get even further outside the box on this and eliminate the changer fingers.

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HagFan

John Fabian · Post by **John Fabian** » 12 Sep 2006 11:36 am

No pix, but I still have my notebook and schematics.

Alan Brookes · Post by **Alan Brookes** » 14 Sep 2006 7:16 pm

Yes, you're right, I should have said hydraulic not pneumatic.

The first cars used water and it was changed to the special brake fluid because it compresses less than water and doesn't cause rust.

As has been mentioned, a little compression on the pedals wouldn't hurt, so using water would create no problem of spilling onto the audience.

I'm not convinced that the drawbacks couldn't be overcome. Plastic tubes are flexible, so the pedals could be made to fold up into the body. Alternatively, keep the rods and let them move pistons in the body.

A better idea would be for the pedals to have a compression bar behind them that could be folded up together with the tubes at the end of the gig. Then the pedals could be removed.

Mac Knowles · Post by **Mac Knowles** » 15 Sep 2006 2:45 am

I remember a long time ago discussing this hydraulic idea with Rusty Walker. He and I have been friends since we were teenagers, and I'll be 70 in a few months, and I've been playin' out since I was 6 years old. The way I see it now is that pretty much all the pitch changing designs out there are a bit of a compromise. The first pedal steel I built in the 60's was almost a direct copy of a D10 ShoBud, the only steel I'd ever seen. Cost me less than $50.00 to build and I played it probably an average of a half dozen gigs a month for 25 years. I still haven't seen too many different designs close up as pedal steels are about as rare as Ferraris around here. So much stuff under there in all of them to do what seems to be such a simple thing. And springs, and compensators, and multi hole bellcranks, and cabinet drop, etc. etc. All seem to try to compensate for some other related shortcoming. We pickers (and builders) know that there's such a minute amount of movement allowed in the changer fingers to have a guitar play in tune or be always out of tune due to all the mechanics involved when one keeps thumping on those pedals. And folks always want to change things around underneath looking for that lost chord. To me, the bottom line is the world needs a changer that'll allow a pedal or lever to change any one or more strings up or down a couple of notes without having to play mechanic, cut new rods, adjust springs, fiddle around for hours underneath and probably screw up the changes you already had. Sure cuts into the playing time and the confidence in your instrument when you're on the bandstand. Is it hydraulics, probably not, or air, or electronics, and I've given it a lot of thought and experimentation in my shop. The KISS principle really needs to apply here. This is why I built the double changer (with a regular keyhead). Both ends of the guitar are like the old pull release changer, one piece fingers,....works for me, until I can think of something better. Thanks for readin' my .02 worth.
Cheers, Mac

Don Blood · Post by **Don Blood** » 15 Sep 2006 5:11 am

I want to be able to just think about changing pitch on a string, and have a sensor pick up my brain waves( if I still have some,) and convert
that energy into movement, via the servo motor. I know there must be a lot of energy there, because why else would it be so hard to think?

basilh · Post by **basilh** » 15 Sep 2006 6:28 am

In the late 60's myself and an avionics techie from Bristol DID construct a simple test bed for a hydraulic mechanism. It WAS promising, but I had my sights set on Ireland and Mac McIver was looking hard at South Africa.

As for the connection dilema, it isn't. See this Quick-action Leak Proof couplers

Baz[This message was edited by basilh on 15 September 2006 at 07:29 AM.]

Ray Minich · Post by **Ray Minich** » 15 Sep 2006 11:03 am

There ain't no such thing as a hydraulic system that won't put oil all over the floor (eventually)...[This message was edited by Ray Minich on 15 September 2006 at 12:52 PM.]