Double vs single raises and lowers.....

C Dixon · Post by **C Dixon** » 6 Feb 2003 9:51 am

A Couple years ago there was discussion about a problem that most PSG's have when these guitars raise a string a half a tone and hold it, then raise it a whole tone (or more), then release the whole tone raise. The string is now a little sharp of the half tone raise. The opposite is true on double and single lowers. IE, it will be a little flat.

This problem was virtually unheard of prior to universals since most non-universals rarely if ever, do this. But on on U's and ever more changes coming along on D'10's, this problem is being noticed more and more. I noticed it first on my U-12 when in the B6 mode.

IE, the E's are lowered to Eb and then the 6th pedal is engaged and released. When this happens, the 4th and 8th strings are left slightly flat. With the 4th being the worst.

The cause of this can easily be seen if one turns the guitar upside down and goes thru the motions. You will see that the E to Eb bellcranks move just a tad more when the 6th pedal is engaged. but they to NOT come back all the way when the 6th pedal is released.

A second place where this happens is with the knee lever that raises the 9th string (U-12) to a D then released while the A pedal is engaged. The C#'s will now be left slightly sharp.

The cause is the E to Eb (or B to C#)crossrods are flexing and/or twisting. On my Excel it is NOT flexing. It is twisting. I can see it happening with no problem.

I said all the above to tell you; that after much study and research, I have found a cure for it. Obviously, the best cure would be to find a metal crossrod that would NOT flex or twist; but this is not possible. Since all metals do it more or less. Aluminum is one of the worst for twisting. Stainless steel is one of the least. But even here, Stainless steel does flex a little bit.

The cure is to procure a piece of angle aluminum 2" X 3/4" by 1/8" thick . Cut a piece so it is about 1" wide. Drill a 1/4" hole in it near the top AND, edge of the long leg. Also drill and countersink two holes in the short leg for mounting to the bottom of the guitar.

Install this piece of angle between the E' to Eb's crossrod and the changer. Caution: predrill the wood and be careful you do NOT drill completely through. That could be a disaster! I KNOW I have done it!!

Use 1/2 in flat head stainless steel phillips head screws. And tighten them securely.

Do this so the longer leg sticks up and is parallel with; and between the 3rd and 4th strings. The 1/4" hole should be closest to the changer. Insert an Emmons' "half-tone" tuner in this hole. (NOTE: you may have to sand or mill the thickness down thinner to get the "ring clip" onto the the slot of the half-tone tuner's swivel).

Then attach a pull rod to the top hole in the 4th string E to Eb bellcrank. Slide the other end of this pull rod thru the "half-tone" tuner. Then install a collar onto the rod about a 1/4" from the half-tone tuner (changer end).

That finishes the installation. The following is how to adjust it:

1. Engage the E to Eb change and hold it.

2. Engage the 6th pedal and release it. The 4th and 8th strings will now be slightly flat (on most PSG's).

3. Reach under the guitar and adjust the half-tone tuner to bring the Eb's back in tune.

That is all there is to it.

couple of things:

1. This works also for the 9th string problem; or any other place where the problem is experienced.

2. If you use your tuner and match the string before and after, you can precisely get it dead on.

If you try this and it works, don't thank me. It was NOT my idea. The thanks go to Mitsuo Fuji of Excel Guitars.

Praise God,

carl

Jim Smith · Post by **Jim Smith** » 8 Feb 2003 11:37 am

Carl, you gave a good description, and I can visualise what you're talking about, but I'm still confused.

You say to hook this extra rod to the 4th string lower finger, yet it raises, not lowers, with the 6th pedal, and doesn't have the problem.

Assuming you meant to say the 8th string, after engaging and releasing the 6th pedal, you say to adjust the half-tone tuner. You say to leave a 1/4" gap between the collar and the bracket, but if it is connected to the lower finger, the only adjustment possible is to lower it more, but the string is already too flat.

Can you elaborate and clarify, please?

C Dixon · Post by **C Dixon** » 8 Feb 2003 12:11 pm

Jim,

Sorry I confused you. You said,

"You say to hook this extra rod to the 4th string lower finger, yet it raises, not lowers, with the 6th pedal, and doesn't have the problem."

Actually what I said was to hook the extra rod to the 4th string E to Eb BELLCRANK. Not the "changer". You do nothing to the 6th pedal. Also, nothing attaches to the changer in this mod.

Here is what is happening and what we are doing to correct it:

1. Engage the E to Eb change. The 4th string bell crank (as well as the 8th) moves "x" amount of distance away from the changer.

2. While holding the E's to Eb, engage the 6th pedal. The extra pull on the 8th string causes both bellcranks (E to Eb crossrod) to move a little further than "x" distance away from the changer. This is because some tension has been removed from the 8th string E to Eb bellcrank; because of the 6th pedal's Eb to D pull on the 8th string.

This does not hurt anything since you are raising the 4th string AND you are lowering the 8th string even further.

3. When the 6th pedal is released, the E to Eb bellcanks come back a little bit, BUT, not as much as "x" distance originally. So the 4th AND 8th strings are slightly flat now. IE, the Eb's bellcranks are greater than distance "x" in this case.

Until you release the E to Eb lever, the 4th and 8th strings will be too flat. Once you release the knee lever, and re-engage the lever it is ok. UNTIL, you engage the 6th pedal again; and now we are back with the problem.

The modification I talked about STOPS the 4th string bellcrank from moving ANY further than distance "x", when the 6th pedal is engaged. Yet still permits the 8th string to go on down to a D.

The end result is:

1. E notes are in tune.

2. Eb notes are in tune.

3. D note on 8th string is in tune. The E note on the 4th string can be tuned easily since it is always "splitting".

AND,

4. Releasing the D back to Eb is NOW in tune.

The reason for placing the collar about a 1/4" away from the "half-tone" tuner is to permit the initial travel of the E to Eb bellcranks unimpeded. In fact after thinking about it, it may even be better to set it to 3/8" to start with; to make sure it does NOT restrict the initial travel of the E to Eb change.

Hope this helps dear friend,

carl

Jim Smith · Post by **Jim Smith** » 8 Feb 2003 12:58 pm

Thanks Carl, I did read it wrong, but I gotcha now!

When I was at Dekley, when Universals were just coming out, we found the problem but never came up with a way to fix it. Jerry Fessenden and I talked about this extensively while I was experimenting with a couple of his Universal guitars. We came up with a similar fix that "might" be easier for some to try, depending on the brand of guitar, availability of half-tone tuners, types of pullers, available space under the guitar, etc.

Mount an angle bracket knee lever stop behind the 4th string lower puller so the adjustment screw can contact the puller when activated. Then adjust the stop screw as you said, so the puller can't move beyond the "x" distance.

Mitsuo's idea is more elegant and easier to adjust, but both will fix the issue. I'm glad to see that almost 30 years later, working solutions are being discovered for this.

------------------
Jim Smith jimsmith94@attbi.com
-=Dekley D-12 10&12=-
-=Fessenden D-12 (coming soon)=-
Stereo Steel rig w/Boss GX-700
IVL SteelRider w/JV-880

Michael Johnstone · Post by **Michael Johnstone** » 8 Feb 2003 6:56 pm

Since I'm a new Excel owner I wonder if you could hip me to Mitsuo's fix for that.He certainly has the most clever half-stop gadget I've seen. -MJ-

C Dixon · Post by **C Dixon** » 8 Feb 2003 7:18 pm

Hi Michael,

Yes, Mitsuo sent me the parts to do it. And it will work ok. My method is a litte more effortless to tune because all one has to do is reach under and adjust the knurled half-tone tuner. With his parts, you have to use a tuning wrench. But BOTH cure the problem completely once it is adjusted correctly.

So send Mitsuo an email; and rather than ask for the parts, simply tell him the problem as simply as you can (as you know he has great difficulty with our language). Then he will send you the parts and a diagram. Or at least that is what he did with me.

And Michael, feel FREE to call me if you want any additional help or explanations.

770-448-8455

God bless you in your quests,

carl

C Dixon · Post by **C Dixon** » 8 Feb 2003 7:29 pm

I forgot something. A lot of you lower your E's on the right knee lever. This could cause a slight problem in locating the L bracket. I lower my E's on LKR, so there is plenty of room between the bellcanks and the changer. This may NOT be the case when you lower the E's with RKR (or RKL).

So to solve this, reverse from a "PULL" with a half-tone tuner, to a "PUSH" with a half-tone tuner installation. That is; instead of pulling on the bell crank back towards the changer, PUSH on it from the nut roller end. It will do the exact same thing; it will just be a pushin' inteada pullin'.

Who said the P/P's were a dying breed?

carl[This message was edited by C Dixon on 08 February 2003 at 07:31 PM.]

Lee Baucum · Post by **Lee Baucum** » 9 Feb 2003 12:01 pm

"the E's are lowered to Eb and then the 6th pedal is engaged and released. When this happens, the 4th and 8th strings are left slightly flat. With the 4th being the worst."

Carl - I've seen your previous posts regarding this problem. This does not occur on my Mullen U-12. After releasing the pedal, both strings come back to Eb, dead on. I've checked with two different tuners and get the same results.

I like my Mullen very much! I will not claim, however, that it has no "cabinet drop" (different thread)!

------------------
Lee, from South Texas
Down On The Rio Grande

C Dixon · Post by **C Dixon** » 9 Feb 2003 2:07 pm

Thanks Lee,

I am proud for you that your Mullen does not experience the problem most U-12's incur. Again, my hat's off to Del.

Interesting.

Tell ya a bit of trivia. I was discussing PSG with a player one time, and I asked him about "cabinet drop". He said, "My guitar doesn't have any at all". So I asked if I could play it. Whereupon I saw that there was indeed cabinet drop. In fact it was just about the same amount as mine, which did not surprise me since both guitars were the same make and mode.

When he sat back down to his steel, and my tuner verified that it did experience cabinet drop on the 6th string when the A pedal was engaged, he remarked,

"Well, it never did that before you played it!". And, he was dead serious.

Go figure.

carl

Lee Baucum · Post by **Lee Baucum** » 9 Feb 2003 6:20 pm

Carl - After telling that story, I doubt anyone will ever let you play their guitar. Too much risk involved!

Del's guitars have a triple raise/double lower changer. Is it possible that having just a double lower changer would somehow improve the leverage and reduce some of the common problems we have discussed?

------------------
Lee, from South Texas
Down On The Rio Grande

Michael Johnstone · Post by **Michael Johnstone** » 10 Feb 2003 12:31 pm

Carl - After carefully reading your description,I think I've got it mentally pictured. But on my Excel I have my Es to Ebs on LKR which means it's a reversing knee lever.As you probably know,on Excels there is no reversing mechanism as such and Mitsuo just mounts the bellcranks upside down and runs the pullrods in the space underneath the cross shafts to accomplish that.What I'm saying is that I can't see how I could mount a stop like the one you describe without completely yanking out all the other pullrods to gain access - which would amount to an almost complete disassembly/reassembly of the undercarrige.And even if I did all that,it would be damn near impossible to get fingers or a tool in there to tweak it because the adjustment would be way down on the other side of the cross shafts under 6 layers of pullrods - which gets particularly dense down by the changer on a loaded U-12. There must be a way though.......... -MJ-

C Dixon · Post by **C Dixon** » 10 Feb 2003 4:39 pm

Michael,

Since you apparently have an Excel that does it differently than mine, I don't believe the mod will work. I have never seen a guitar excluding a P/P that runs the pull rods underneath the crossrods. I never new he did this on his earlier models.

Sorry it won't work because it is a great mod.

crl

Pete Burak · Post by **Pete Burak** » 10 Feb 2003 5:06 pm

FWIW, BMI's run the pull rods on either side of the Bell Crank also (in order to eliminate the reversing mech.).
I used to have a BMI S12U but never checked it for this anomoly.

Michael Johnstone · Post by **Michael Johnstone** » 10 Feb 2003 8:06 pm

My guitar is less than a year old.

Pete Burak · Post by **Pete Burak** » 11 Feb 2003 9:21 am

The thing about this anomoly as I see it... it corrects itself as soon as you release the pedal/lever, and it only drifts about 2 cents anyway.
In the context of an ensamble playing a given passage of music, it's a musical non issue (again, IMHO

).
This is analogous to tuning the E strings on most steel brands (any configuration S10, D10, S12U)... the E note looks different on a tuner with A+B enguaged vs. no pedals.
Same with string 6 G# going flat with A+F enguaged (again, most any brand/config).
You can see it on a tuner, you can hear it if you're in a silent room, but bottom line... folks play and record without regard for hysterisis, cabinet drop, and now add to the list, cross rod flexing.
In the big picture of learning and playing steel, is cross rod flexing on an S12U an issue that folks should be worried about?... For the overwhelming majority I would say not, but having "been there" myself (brought my tuner and steel into Don Christiansons office), I commend those who pursue the "perfect mechanism"!

C Dixon · Post by **C Dixon** » 11 Feb 2003 10:48 am

Pete,

Thank you for your candor. I appreciate your thoughts. Although I disagree with them. It depends on the player. Some are content, as you say with all kinds of hysterisis and cabinet drop etc, etc. But for those of us whose ears go bonkers when ANY string changes its set tuning, the following manufacturers have come up with remedies:

1. Franklin and Emmons-compensators to counteract hysterisis.

2. Emmons, Remington and Excel-counter force mods to eliminate "cabinet drop" related problems.

3. Excel-compensators to prevent double (and triple) raises from overiding single and doulbe raises (and lowers) from coming back too flat (or too sharp).

4. All manufacturers (if requested) compensators to couneract JI induced detuning such as strings 1 and 7 when the pedals are down versus up.

5. Emmons and a whole slew of others-compensators to bring "splits" into perfect tune.

Why?

I find it inconceivable that these manufacturers (and others) would take the efffort in time and material, IF the problems were just "minor" and/or only a select few were concerned about it. I sight the Emmons' LeGrande III as a perfect example.

The counterforce option costs 300 dollars (approx) PER neck to get it. I just can't see this being sold as much as it is; if the reason was frivolous.

Not saying you called it frivolous. But it is the complaining customer; NOT the satisfied customer that drives ANY manufacturer to make improvements. NO automobile today would have anywhere near the "goodies" it has had it not been for the complaining customer.

Proving that the negative terminal on any battery is JUST as important as the positive terminal!

Sure, some prefer to "live with it like it is". Like, some prefer a stick shift still on an automobile. But believe me zillions have paid a fortune (all total) for automatic transmissions. Same for power brakes and power steering not to mention torsion bars, shock abosorbers, automatic antenna raisers, disk brakes, electric side view mirrors, etc, etc.

In my own personal case, I not only can't stand a string that changes pitch when it is not pulled, I get downright uptight with the manufacturer for NOT doing something about it in the first place.

Like the tops of strings NOT being dead level at the nut rollers. Simply NO excuse for this. NONE. This problem ShOULD have been solved 30 yrs ago! Same for hysterisis and same for rattles and noises under the guitar. And the list goes on.

I would gladly trade esthetics and "pretty" colors if I had a choice of a PSG with NO hysterisis, cabinet drop, etc. To me MOST of the real value of a PSG is UNDER the guitar and how this underling affects the permormance of the instrument.

Sound is of course absolute on any musical instrument. But assuming the sound is the same, there is NO reason why the manufacturers should not have solved the aforementioned problems a long time ago. Instead of spending SOOOOO much time on esthetics.

My thoughts of course.

God bless you all,

carl

Jim Smith · Post by **Jim Smith** » 11 Feb 2003 10:56 am

it corrects itself as soon as you release the pedal/lever, and it only drifts about 2 cents anyway.

Pete, the guitars I've seen this on were in the 15-20 cent range, much more than "normal" cabinet drop. That, added to the fact that the knee lever is typically held in all the time while playing B6, does make it a worthwhile issue to solve, IMHO.

C Dixon · Post by **C Dixon** » 11 Feb 2003 12:20 pm

on mine it is 22 cents on the D versus the Eb.

Pete Burak · Post by **Pete Burak** » 11 Feb 2003 1:21 pm

Hey, I don't disagree with the existance of this hysterisis and that it varys from brand to brand.

Would you agree though, that quite likely in the ballpark of 90%+ of ALL the most "Famous" steel guitar music ever recorded was done on instruments that, by todays standards, are mechanically obsolete with respect to cabinet drop and hysterisis?

In this case the cause is different, but the symptom (strings not returning to pitch) is the same.

I still contend that if you keep playing along with the band that you will never notice this issue and certainly noone else ever will.

I simply don't feel it's a big enough deal to reccomend publicly that S12U players risk possibly irreparably damaging their guitars in an attempt to follow the above posted procedure!

Carl, you write "But for those of us whose ears go bonkers when ANY string changes its set tuning, the following manufacturers have come up with remedies:"

You have stated publicly that your guitar has really bad cabinet drop.
Why haven't you moved on to one of the brands you mentioned above?
So you'll have to change a 3rd string once in a while!

With all do respect, I hope you can understand why I won't be drilling into the bottom of my steel any time soon!

C Dixon · Post by **C Dixon** » 11 Feb 2003 1:35 pm

"Why haven't you moved on to one of the brands you mentioned above?
So you'll have to change a 3rd string once in a while!

"

I would have gladly done it; if ANY builder I contacted would have considered ANY of the changes I wanted. NOT one was interested. And I do not fault them. Most manufacturers are not in business to change the basic design of their guitars to cater to an indidual. And rightfully so.

Mistuo was an exception. And I am very greatful for it. God bless him for it. Because with his new mod for eliminating cabinet drop, (which I will be installing soon), plus the mod for solving the problem this thread is all about; PLUS the fact that it is ONLY one of two PSG's manufactured that does NOT break strings; PLUS it is the only PSG with a 5 raise, 5 lower changer, it is my 40 yr dream come true

carl

PS: ANY person with an ounce of mechanical aptitude would have absolutely NO problem installing the device Mitsuo came up with. IN fact it is less than a third what installing a knee lever kit would entail. And most manufacturers been sellin them forever!

And anybody that would cause irreparable damage to a PSG doing ANY thing to it, needs someone to set it up and tear it down before and after playing it; PLUS tuning it for the guy; because that would involve more risk than putting this simple mod in.

Earnest Bovine · Post by **Earnest Bovine** » 11 Feb 2003 1:56 pm

<BLOCKQUOTE>quote:<HR>I still contend that if you keep playing along with the band that you will never notice this issue and certainly noone else ever will.

I simply don't feel it's a big enough deal to reccomend publicly that S12U players... follow the above posted procedure! <HR></BLOCKQUOTE>
The reason you don't notice it is that most players don't use these pedal (knee) changes on their setups. Do you?

The most common place to see the problem is an a Universal tuning. Carl sees it on his E string (.030") when releasing from --D up to -D#. Other universal players see it on their B string (.036"), when releasing from +++D down to ++C#.

And some non-universal players avoid them precisely because they don't play in tune! I know; I am one of them. On my E9, I like a knee lever that raises my B (.017") to +++D. But when I release +++D down to ++C#, it is too sharp for me to use. The only exception for me is the Franklin steel, which does this change almost perfectly in tune.

Michael Johnstone · Post by **Michael Johnstone** » 11 Feb 2003 3:31 pm

I too have the problem on the two strings Earnest mentioned on my new U-12 Excel but they aren't so bad I couldn't live with them if I had to.My guitar came with the cabinet drop compensator Carl mentioned and it works splendidly - in fact,the guitar is capable of being so in tune that it sounded funny to me at first till I got used to it.And because everything about the guitar is so in tune,I would really like to be able to take care of this cross shaft flex problem as well and I would gladly mount a gadget on my guitar if it was well designed and did the trick. I do know a few guys who would be well advised to let somebody else work on their guitars but that's a different issue.As far as the Excel's design and Mitsuo's willingness to build anything you want,it may a blessing and a curse because I've talked to 4 different Excel owners and they describe vastly different mechanics than my guitar.Apparently he makes 2 different kinds of halfstops,2 different ways to hook up the anti-detuning device,2 different ways to reverse a knee lever,different amounts of raises/lowers(mine has 7 raises & 5 lowers),2 different kinds of pullrods and collars,etc,etc.And on my guitar you can anchor the strings from either end of the guitar just my relocating the set screws.I kind of like all that though because it makes the guitar wide open as far as customization. And I have broken 2 3rd strings in the 3 months I've had the guitar but then again I'm sitting behind that thing about 3-4 hours a night pumpin' that "B" pedal. -MJ-

Pete Burak · Post by **Pete Burak** » 11 Feb 2003 3:57 pm

"And anybody that would cause irreparable damage to a PSG doing ANY thing to it, needs someone to set it up and tear it down before and after playing it; PLUS tuning it for the guy; because that would involve more risk than putting this simple mod in."

"Caution: predrill the wood and be careful you do NOT drill completely through. That could be a disaster! I KNOW I have done it!!"

There ya go!

Carl, You've told us several times that the cabinet drop your steel has is due to your modifications, not Mitsus design.
Maybe the other folks you ran them by were simply able to predict the impending negative impact issue and politely chose to pass (pure speculation on my part, but I see it often in high tech).

You make a good case for Excell being a good brand (actually, I know for a fact that they are a good brand), and I have no reason to doubt that it is in fact your dream come true.

And I'm glad that someone is trying to work the bugs out of this instrument we all love!
I mean, it's only what... quarter past 2003?... about time, eh?
While we're young, steel builders!

I wish they'd just solve the root cause, instead of "mod'ing", "compensating", "counterforcing", ext... it to death!

Earnest, I do use the exact changes that this thread is about, and I use them on every gig.
I used to really let this type of tuning imperfection bug me, but upon learning/seeing that you can change the tuning of a string as much or more by simply running you finger up and down the string surface, it became apparent that the tail chase was effectively "called on account of reality" (in my case at least).

So, if you tune your Emmons LeGrande III perfectly, run your finger up and down the string, and check the tuner, will it still be at the same exact pitch as before?

I don't know about you guys, but I rest my fingers on the strings behind the bar, and I move my bar hand up and down the neck all the time.
I'm probably doing it wrong!

C Dixon · Post by **C Dixon** » 11 Feb 2003 4:37 pm

"Maybe the other folks you ran them by were simply able to predict the impending negative impact issue and politely chose to pass (pure speculation on my part, but I see it often in high tech)."

You are 100% correct. it was (and IS) indeed purely speculation on your part.

Plus, IF there is or ever has been ANYthing "high tech" about a PSG, I fail to see it. In fact it is even less than rudimentary mechanics taught in mechanics 101 class in HS.

You are also 100% correct about rooting out the cause rather than compensating for it. The problem has been that NO one that I know of has found the root cause of two of these three major problems.

So in the meantime, many of us would like to go with a "fix" rather than put up with something annoying "waiting for the perfect time for the harvest" Especially if that fix cures the problem cold dead in its tracks.

We do KNOW of the root cause of hysterisis and it is the string beyond the roller nut not all coming back after a raise as opposed to a lower. Keyless comes the closest to curing that root cause of anything I know of.

But what comes even close is to use Emmons type compensators. Because when adjusted properly, they stop it cold dead in its tracks, EVEN though it is a compensator and does not "solve" the root cause.

The Emmons LeGrande III has zero cabinet drop when adjusted properly. And I mean zilch. NONE, nada, etc. No it did not tackle the root cause. It simply compensates 100% for the problem. So does Excel's compensator for cabinet drop. I can't speak for Remingtion. I assume it does too.

Because of experience with these problems, I have NO hesitancy to use yet another "compensator" to solve a MAJOR problem (for me at least). Apparently I am not alone, since Excel, Franklins, Emmons and others were offering compensators before I was aware of the problem.

Again, If YOU are happy without using them, fine. I am not happy without them.

Thank God there are some that like to accomadate those of us that are NOT content to go outside to a little shed to read the morning paper (after coffee). Instead of assuming I simply wanted something high tech instead. Seems to me I recall an ole saying about plumbers,

"Cold water on the right, hot water on the left, ***** don't run up hill and payday's Friday!

carl[This message was edited by C Dixon on 11 February 2003 at 04:58 PM.]

Pete Burak · Post by **Pete Burak** » 11 Feb 2003 5:45 pm

One solution I've read about is putting P6 on a knee lever.
So when you go from Eb to D to Eb on string 8, what effectively happens is that you are really going from Eb (to E) to D (to E) to Eb.
This happens so quickly that the E note is not heard, and the hysterisis is not an issue.
The analogous change for the B string would be to rlease the A pedal after going to D, to "reset" the C# note.
C# to D (let off the A pedal while on the D note) to C#. Again this is played in a manner such that the D to C# is seemless and the hysterisis is not in play.

Carl, my reference to High Tech was simply that I work in High Tech and attend many many engineering modification meetings where alot of folks' ideas are politley dismissed by those of greater knowledge/expierience.

FWIW, I use a compensator on my 6th string to sharpen it in the A+F position.
But it's just another rod hooked to the F lever, not a "mod" if you will.

Don't be offended by my challenging of your or anybodys "new mod". These things come and go and some work and some don't.
Or they work for limited configurations/brands/ect...

Man!... for something that is less than rudimentary mechanics taught in mechanics 101 class in HS it seems incomprehensible that NO one has found the root cause of two of these three major problems.
Maybe them Carter folks?!!!