Where is the Half Stop Mechanism on a modern Excel U12

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Baron Collins-Hill
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Where is the Half Stop Mechanism on a modern Excel U12

Post by Baron Collins-Hill »

My D# to D/C half stop is not in tune, and I can't for the life of me find the mechanism that is responsible for that action. I'd like to be able to tune that D or back the whole thing out and just go straight to D.

Can anyone explain what I should be looking for? Photos are helpful if you have them.

Thanks,
Baron
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Pat Chong
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Post by Pat Chong »

Hi Baron,

A picture of your half-stop assembly would help identifying if there is a tuner part on it.

.........Pat
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J D Sauser
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Post by J D Sauser »

Since on these the changer finger MOVES toward the pick-up to lower, the max lower stops the finger with little stop screws in FRONT of the changer (between changer and pick-up, facing the pick-up). You set the primary lower there and AFTER that, the “mixed”/“split” at the changer end pul rod nylon hex tuner nut.

So, if in E9th you’d split une the A-pedaled whole step raise agains the B-to-Bb lower lever, you’d first tune your B-to-Bb-lower with that set screw (providing enough pull at the nylon pull rod hex tuning nut PLUS SOME! You will have to feel your lover slightly over-runing the stop screw stop, without further affecting pitch).
Then you engage your whole step raise and then the lower and tune the split value.
The split lower requires mire travel to lower a half step, because as strings are stretched further with the whole step raise, the travel for pitch change becomes longer and longer.

… JD.
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Baron Collins-Hill
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Post by Baron Collins-Hill »

Pat: I can’t even find the mechanism to take a photo of

JD: those little screws are for splits and don’t seem to be involved in my D# change that goes to D and then C#.

I tuned the C# lower up to D but can still feel the half stop making the transition less than smooth, I just can’t find or work out the mechanism for the life of me

Thanks
Baron
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Bobby D. Jones
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Post by Bobby D. Jones »

Turn the guitar over, Move the pedal or KL that makes the D# move. Look around the cross rod that moves When D# is lowered.. The stop may be hooked to the cross rod. with an under the guitar adjustment that can not be seen from the top of the guitar.

Once you find the Half Stop post a picture.
Good Luck in your search.
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J D Sauser
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Post by J D Sauser »

Baron Collins-Hill wrote:Pat: I can’t even find the mechanism to take a photo of

JD: those little screws are for splits and don’t seem to be involved in my D# change that goes to D and then C#.

I tuned the C# lower up to D but can still feel the half stop making the transition less than smooth, I just can’t find or work out the mechanism for the life of me

Thanks
Baron
Sorry. I was reading/writing from my phone, and even so, I don’t undestand how I got to mistake your problem of a feel stop with split tuning. WELL, maybe the fact that I did answer right after waking up, sorry for that!

I don’t have any feel stops on either of my Excel Superbs. I SEEM to remember that one had a pull on an bass string tuned so it was usable and also generate an “on the money” feel stop on the E9th 2nd string when hitting the Changer.
Fuji has come up with a wealth of mechanical solutions and never shied away from replacing his last great idea with yet a newer one, while others kept stagnant on their “if it ain’t broke-don’t fix it” attitude. I admire that so much of him.

Evidently, you can run a rod into a bass pull and tune it there. But then, you’d probably need to order an additional rod and bell crank… which is like writing Mr Fuji and asking him to answer your question.

I dislike resistance-adding feel half stops, not only because once hit they add resistance but because they really work in one way and are very difficult to feel on the way back.
I always immagined a “reader” on a setable cam to indicate that feel stop both ways without really adding resistance past the point marker.

But that isn’t an answer to your question either.



I would be indeed interesting to see what’s going on underneath, following that lever’s action. Ee

… JD.
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Jerry Overstreet
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Post by Jerry Overstreet »

I know almost nothing about Excel guitars. I do know Fuzzy does some things a bit different.

But, If you aren't able to locate it, maybe your guitar doesn't have a mechanical half stop mechanism? Many guitars don't and it's an option for some.

If your 2nd string and your 9th string are on the same lever, search around here for players using the 9th string as a feel stop point for the D#/D/C# tuning.

If you only want to lower string 2 to a D note, your final lower stop, whatever the changer design, should let you adjust it the same way as any other lower tuning of your guitar.
Pat Chong
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Post by Pat Chong »

Hi Baron,

The D# to D/C# half-stops are usually on the RKR, and I would figure yours is there, too.

My Dekley has one, also, maybe like yours, maybe not.
The lever action moves down a rod and runs into a spring (that's the half -stop), it is not tuneable, per-se.


The normal pedal or lever is hooked up directly with the pulls. Look at the operating parts of your pedals and levers. Press it and you can follow the movement from lever, to rod, to shaft crank, to rod puller. The rod goes the the changer.

Anyway, now compare what the normal lever has to the lever with the half-stop. Anything different is probably connected with the half-stop mechanism.

Another idea is to take a pic of the undercarriage, and someone could identify the half-stop parts......?

Luck on your search.....Pat.
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Marco Schouten
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Post by Marco Schouten »

Your guitar might use the split tuner for the half stop, my JCH guitar does.
It works like this: tuune the second string full tone lower with the nylon tuner of the second string. Tune the half tone lower of the second string with the nylon tuner of the 9th string. Tune the 9th string half lower with the split tuning screw of the 9th string. This works only if you lower the 2nd and 9th string on one knee lever.
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Michael Johnstone
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Post by Michael Johnstone »

On my Excel U-12, the half-stops and I have them on 2 different levers, are nothing like any other guitar I've seen. Essentially it's comprised of 2 bellcrank looking parts facing each other. The one driving the cross shaft has a smooth face on it and it's facing another similar part connected to the knee lever mount which has 2 hex head machine screws of slightly different lengths threaded through it an an angle. When you engage the lever, the tip of the longest screw makes contact with the face of the smooth faced bellcrank. When you continue pushing the lever, it starts activating the change. When BOTH screw tips make contact, you can feel it and that's the half-stop point. If you keep pushing, the tip of the longest screw lifts away from the face and the shorter screw continues the second half of the change until the smooth-faced bellcrank's external stop makes contact. It's very simple and hard to spot if you're used to seeing something else. But when you finally see and understand it, you'll see why Mitsuo Fuji is an engineering genius. BTW, you adjust the half-stop point by changing how far the shorter screw is sticking out by turning it incrementally and once adjusted and if you stay with the same string gauge, it'll hold for years. What I like is there's no spring to add unnecessary tension to the second half. There's some difference but it's about the same difference in mechanical advantage you'd have between 2 adjacent holes on a bellcrank.
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Image
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J D Sauser
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Post by J D Sauser »

Michael Johnstone wrote:On my Excel U-12, the half-stops and I have them on 2 different levers, are nothing like any other guitar I've seen. Essentially it's comprised of 2 bellcrank looking parts facing each other. The one driving the cross shaft has a smooth face on it and it's facing another similar part connected to the knee lever mount which has 2 hex head machine screws of slightly different lengths threaded through it an an angle. When you engage the lever, the tip of the longest screw makes contact with the face of the smooth faced bellcrank. When you continue pushing the lever, it starts activating the change. When BOTH screw tips make contact, you can feel it and that's the half-stop point. If you keep pushing, the tip of the longest screw lifts away from the face and the shorter screw continues the second half of the change until the smooth-faced bellcrank's external stop makes contact. It's very simple and hard to spot if you're used to seeing something else. But when you finally see and understand it, you'll see why Mitsuo Fuji is an engineering genius. BTW, you adjust the half-stop point by changing how far the shorter screw is sticking out by turning it incrementally and once adjusted and if you stay with the same string gauge, it'll hold for years. What I like is there's no spring to add unnecessary tension to the second half. There's some difference but it's about the same difference in mechanical advantage you'd have between 2 adjacent holes on a bellcrank.
Image

Image
INTERESTING!
I did NOT find that system on either of my two Superbs!

Basically, it's two different leverages and thus two different resistances:
- The first stretch is with the leverage point the furthest away from the fulcrum, thus slower but "easier".
- The second part is with the leverage point closer to the fulcrum, making it quicker from there on, but also at a higher resistance.
... thus creating the feel-step.

Thanks for sharing!... J-D.
__________________________________________________________
A Little Mental Health Warning:

Tablature KILLS SKILLS.
The uses of Tablature is addictive and has been linked to reduced musical fertility.
Those who produce Tablature did never use it.

I say it humorously, but I mean it.
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