The correct orientation of Rack and Barrel

Jim Kolman · From: New York, USA

there are a few notes on the board about this, but I can be slow. I put this pic together as a guide.

Tom Wolverton · From: Carpinteria, CA

I prefer the "incorrect" orientation. Seems to work better and the barrels don't fall into the U. But I'm "all ears" if this isn't correct. It just seems to work really well.
_________________
To write with a broken pencil is pointless.

Jay Yuskaitis · From: Massachusetts, USA

I agree with Tom. Jay Y.

Dan Beller-McKenna · From: Durham, New Hampshire, USA

I seem to recall a post on the Forum in which someone claimed that Jim's Correct method was the originally intended design, but that someone at the Sho Bud factory got it wrong in assembling some of the earliest R+Bs, and the "Incorrect" way (that most of us are used to) became the norm.

Does this ring a bell???

Tom Wolverton · From: Carpinteria, CA

Dan, that is what I recall as well. When I look over the many photos I have of various 'buds, they usually have the rack turned to the "incorrect" orientation. When James Palenscar set-up my Sho-bud, he put it in this orientation as well and I think it is the better performing orientation. I tried one rack the other way, and the barrel had seating problems that created tuning issues for me. just my 2 cents worth.
_________________
To write with a broken pencil is pointless.

Jay Yuskaitis · From: Massachusetts, USA

I had a "Baldwin Model" I bought brand new in 1970 and a Model 6139, brand new in 1972. The rack and barrel were set up the supposed wrong way. They were the most trouble free pedal steels I ever had. Just as easy to change pulls as the "Fender Cable Models". I will admit, the pedals were a might bit stiffer than todays steels. Just my opinion. Jay Y.

John Billings · From: Ohio, USA

Every R&B guitar that I have seen, used the "incorrect" method. All but one! Here is my very early '67 S-10. Note the sand-cast aluminum rack mounts. But there is a small gnat in the ointment. The first rack was not built correctly, as one of the racks would not rotate completely around. So,,, was this guitar set up this way because one rack wouldn't turn? So,,,, assemble them all that way so it doesn't look like a mistake? I don't know.

BTW, the racks on my relatively same era Crossover Custom were just the opposite.

Dan Beller-McKenna · From: Durham, New Hampshire, USA

John, I think it may have been an old post of yours about this guitar that I was remembering. Yes?

John Billings · From: Ohio, USA

Dan,
Quite likely, as I've posted some pics of the resto before.

John Groover McDuffie · From: LA California, USA

+1 for the incorrect method - my old Bud was that way. Blackie Taylor added two knee levers to it and kept it set up that way.
I guess if you count Blackie it's +2! Very Happy

Alan Berdoulay · Posted 25 Jun 2013 7:26 pm

Here ya go.....from a tuning R&B thread......

Michael Yahl
From:
Tucson, Arizona
Posted 17 Jan 2012 1:38pm
No, the barrel should never be in contact with the rack at rest. Always have 1/64-1/32" (.015-.031") between the rack face/edges and the face of the barrel. If there is contact, you'll chase your tuning 'till you're blue.

Also just a note, I found in an old thread discussing the R&B's, that David Jackson designed this system and the intent was that the rack was oriented with the open side (channel) facing the barrel. It was speculated that at some point during production assembly, someone set them up backwards and from then on that's the way they were assembled.

This causes some problems with tuning the barrels when the solid face of the rack is facing the barrels as most of the wire spring tips on the barrels (yes, there should be a protrusion of about 1/16" or .062" of the spring end past the face of the barrel) have a tough time finding a point to catch on in order to effect the barrel adjustment. I beleive that this has been the cause of the most frustration with the R&B system.

By flipping the racks so that the open side is adjacent to the barrel face, it provides a much better surface, the inside of the rack, to arrest the rotation of the forward end of the barrel and permit a positive feel for the adjustment.

At no time should the barrel be is a full "lock" condition where the spring is fully compressed.
There must be some gap in the spring so that in the event the rod rotates, during normal playing, to a point where the end of the spring tip is aligned with a solid surface on the rack, the tip has the ability to be pushed backwards into the barrel face until it is flush. This is another mistake commonly made during initial setup. When this occurs and there is insufficient travel for the spring tip to retract, it will definately affect the tuning for whatever string when it is activated. Hence, this is one of the reasons that the R&B system gets bad press.

I've heard of guys cutting the spring tip off! This just disables the entire tuning aspect of the barrel as that is the key feature that prevents the forward portion of the barrel from rotating thereby allowing the rear portion to rotate and adjust on the thread.

Note: There are 40 threads per inch on the barrel. This is the same as the threads on a micrometer. 40 TPI divided by 1 inch gives a .025" pitch/travel in 1 rotation.

So, there you have the design intent and criteria for these little jewels.

Todd, once you've gone through it enough times and have that 'AH HA!' moment, it won't seem so difficult.
_________________
"Don't fergit to kiss yer horse!"
'72 Sho-Bud Professional D10, (in pieces .....)& '78 MSA Classic XL D10
Peavey Session 500 BW, Crate Digital Modeling Amp

WildHorse Pedal Steel Guitars, LLC
http://www.psgparts.com/

John Billings · From: Ohio, USA

"I found in an old thread discussing the R&B's, that David Jackson designed this system and the intent was that the rack was oriented with the open side (channel) facing the barrel. It was speculated that at some point during production assembly, someone set them up backwards and from then on that's the way they were assembled. "

I'd like to hear that from David. I see no logical reason to continue making a mistake. just because someone put a guitar together incorrectly as far as the design is concerned. Doesn't really make sense. Perhaps someone could ask David? Then we'd know fur shure!

Ron Pruter · From: Arizona, USA

I totally agree with Tom. I've had it "Correct and incorrect" The pin seems to get jammed up and bent on the "correct" method. The drawing is not correct in that the barrel end isn't as large as shown and tends to want to slip down wedging the pin and possibly, as Tom said, slip into the groove.
I've found that keeping the barrels in great shape really helps the situation. BTW, PSG parts makes great ones. I recommend disassembling them and cleaning them in naptha with an eyelash brush. Don't
oil them. You want them to have a little resistance so they stay in tune. Make sure the pin is sticking strait out of the barrel. It's OK to bend them a little to true them up.
I used to hate this system, now after "incorrectly" using this system, it's not bad at all. BTW,FWIW, I used to work at ShoBud in the 70's.
_________________
Emmons SKH Le Grande, '73 Fender P/J bass, Tick tack bass, Regal high strung, USA Nashville 112.

Michael Yahl · From: Troy, Texas!

Wow, I'd forgotten that I wrote all that!

What I missed was a reference to where I got that information. Here's the thread that I was referencing
http://bb.steelguitarforum.com/viewtopic.php?t=199776&highlight=rack+barrel+david+jackson

This is the statement that Benton Allen made in his post,
" According to David, his design originally had them facing this way (referencing open side to barrel face). Later, someone at the factory mistakenly installed them facing the opposite direction, and they worked OK that way also."

I made the assumption from his wording that he had actually had a discussion with David about this subject. It is actually hearsay coming from me as a second person having read the post, however good engineering practice would support the statement. On the other hand, sometimes design intent doesn't always factor in the possibility of someone doing something wrong and still having the component function 'pretty much' as it should.

The fact that, in a position with the barrel face against the flat side of the rack, fails to provide a satisfactory point of contact for that spring 'tit'. With the tit in a 6 or 12 o'clock position, it only has about .010" to catch on the top or bottom face of the rack and that's IF the end is long enough. From that point as the rod is rotated only the very end surface is in contact as it travels across the bend radius on the rack until sufficient tension builds in the spring to hold it. This also creates a bending moment at the point where the spring protrudes from the face of the barrel. You essentially create a .080" long lever and now it takes very little force to bend that protrusion over. This now fails to allow the spring to travel back through the hole should it free rotate and come into direct contact with the face of the rack.

Theoretically, the spring tit should not be able to fit over the top or the bottom of the rack faces. But, due to manufacturing variances this does occur. It you examine a series of racks you will find that the holes may tend to be toward either the top or bottom face. Add to that the oversize hole in the rack, that allows for the rack to pivot and not bind the shaft, you have now built up sufficient clearance for the spring tit to go over the top or bottom face and the barrel face to fit flush to the rack face.

This is also the reason that they will drop into the channel when installed with the open side of the rack to barrel face. Fix this by squeezing the top and bottom rack faces slightly closer together. These vary greatly and I believe that they should have a mean dimension over the outside of about .328"(21/64"). More of the manufacturing variances come into play here also as you can find many racks with uneven length top and bottom faces. These are usually most noticeable on those where the holes are offset up or down. These two features will go hand in hand as the part slipped during the forming process or the tooling was worn. However, the pivoting feature and the over sized rod through hole still allow the rack to pivot and make 2 point contact with the barrel face.

Now, with the spring tit 'inside' the open channel, it now has 2 solid faces and 4 individual points for the tit to make full length contact. The bending point for the tit is now flush with the face of the barrel. It will take a great deal more force to cause that spring tit to bend. Of course all bets are off when the barrel is is a full lock situation with the compression spring fully compressed and the leverage of an allen wrench applied to the end of the rod.

There are certain constraints in this design. The head of the front of the barrel is Ø.3438 (11/32"). If that number sounds familiar, that is the dimension of your string spacing from finger center line to center line. If everything was exactly on size, perfectly aligned and square, the heads of the barrels would be touching. But, look down at two adjacent barrels. Looks like all kinds of space there, right?

Tolerances. Design for functionality. We're dealing with a bunch of metal components bolted to a slab of wood that expands and contracts with time and the weather. This is why there has to be some slop built in and it exists in every guitar new or old. If these contraptions were built to aerospace tolerances, these things would fail to function by the time the new owner received it and got it out of the case. Going from North Carolina to Arizona! Forget about it... Some 'slop' is our friend.

MY EXPERIENCE is that most of my customers that I tell to set their racks with the open side to the barrel, report back that it solved the majority of their tuning problems.

You may choose to do whatever you wish as it is your guitar.

This was simply to help you all understand why they are what they are.

A few things that I'd like to reiterate from the posts above is that these barrels need to be CLEAN and NO LUBRICANT! Brass has a relatively high coefficient of friction when run against itself. Ever put brass pipe fittings together dry and noticed how they began to tighten up before you knew they were tight? This light friction between the clean surfaces helps them to maintain their position as well as the spring adding an additional tension and anti-rotation force.

Also, that spring 'tit' need to be at least .062"(1/16") to .093"(3/32") long to function properly. I grind mine to .093". (Longer is better, right?) If you find one that is too short, re-bend the spring. I know that it's a pain without fixtures but it can be done. When finished, the tit should slide in and out of the hole without binding. I know that don't sound quite right but you get the picture.

I also suggest that when you preset them, find the center of the threaded distance, by threading the part with the set screw on a full 4 threads. Then from there count the number of turns until it gets to spring lock and divide by 2. The 4 threads should give ample engagement to prevent excessive force from damaging the thread. Any less and you could deform them or over-travel during tuning and have it come apart. That sucks...
_________________
"Don't fergit to kiss yer horse!"
'72 Sho-Bud Professional D10, (in pieces .....), '78 MSA Classic XL D10, '69 Emmons PP, Fender 2000
Peavey Session 500 BW, Crate Digital Modeling Amp

PSG PARTS
http://www.psgparts.com/

Jim Pitman · From: Waterbury Ctr. VT 05677 USA

What are the disadvantages of rack and barrel?
wieght?
less fulcrum point maybe?

Richard Sinkler · From: aka: Rusty Strings -- Missoula, Montana

Weight and noise are the 2 that I can think of. Otherwise, I love 'em.
_________________
Carter D10 8p/8k, Dekley S10 3p/4k C6 setup,Regal RD40 Dobro, Recording King Professional Dobro, NV400, NV112,Ibanez Gio guitar, Epiphone SG Special (open D slide guitar) . Playing for 54 years and still counting.

Dan Beller-McKenna · From: Durham, New Hampshire, USA

Although, like Richard, I too love my rack and barrel, I would add that you lose the control over length and stiffness of travel, as well as timing multiple pulls on one pedal or lever that you have on a more modern all pull system. On the other hand, I don't find my R+B to be particularly noisy.

Forum Index > Pedal Steel		Next oldest topic :: Next newest topic

All times are GMT - 8 Hours	Jump to: