King 7B mods

[bassboneman69]

Just got a decent 7B.
My first King instrument…

This one looks to be a previous school instrument.
Short of scratches throughout, it is in very good shape.

I am having the slide gone over -
For those who have used or still use King basses what are some suggestions for further modification(s)?

I was thinking of switching string linkage to mechanical. The D attachment arm rubs on my neck. (I have a skinny neck). Perhaps having lead pipe pulled too.

Looking forward to hearing what y’all have to say.

Thanks, Sam

[bigbandbone]

Get to know it first. You might find you like in stock configuration. They are dynamite horns.

[BGuttman]

I played a King 7B for 40 years and didn't do a thing to it. Worked great as it is.

As far as the string linkage, I had to replace the plastic part 3 times in those 30 years (twice on F, once on Gb). I got some 10 years on a typical string. But if you are dead set on converting to mechanical, good luck. I'm sure a good tech can do it for you.

[Kingfan]

Just got a decent 7B.
My first King instrument…

Are you talking about 7-B Duo Gravis with dependent valves or a 2107 with independent valves?

[bassboneman69]

Just got a decent 7B.
My first King instrument…

Are you talking about 7-B Duo Gravis with dependent valves or a 2107 with independent valves?

It’s indi…

[bassboneman69]

I played a King 7B for 40 years and didn't do a thing to it. Worked great as it is.

As far as the string linkage, I had to replace the plastic part 3 times in those 30 years (twice on F, once on Gb). I got some 10 years on a typical string. But if you are dead set on converting to mechanical, good luck. I'm sure a good tech can do it for you.

The f attachment plastic part is quite loose. That may have to be addressed if I don’t go w mechanical linkage.

[bassboneman69]

Thank you to everyone who has responded!

[brassmedic]

Is it like this?

king.jpg

I haven't done that particular conversion. You would have to braze new attachment points to the stop arms, and it looks like the links would have to be very short, and you probably would have to modify the levers. Could be difficult. Maybe someone here has done it?

[Posaunus]

I'm a fan of string linkages - they've always worked well for me. Don't give up too easily. May need a simple (inexpensive) tune-up by a tech.

[bassboneman69]

Is it like this?

king.jpg

I haven't done that particular conversion. You would have to braze new attachment points to the stop arms, and it looks like the links would have to be very short, and you probably would have to modify the levers. Could be difficult. Maybe someone here has done it?

Yes…but mine isn’t as pretty (yet).

[boneagain]

Nice, clear photo, Bassboneman69!

Shows a couple significant points:
1) The "F" rotor shows what you can get a tech to make for you if you get tired of the plastic breaking every decade or so;
2) the stop arms show one of the biggest advantages of the strings.

That big advantage is that the effective action lever of the string is from the outside of the stop arm to the center. If one brazes on an anchor for something like a miniball, the effective lever length will be longer. That translates into more travel at the valve end of the lever. That, in turn, means that the tight clearance between that second lever and the first valve will become more critical. OTOH, that will mean LESS travel under the finger...

Speaking of fingers, a second advantage of the string is that you CAN tune the exact position of the string clamp screw to some degree to adjust finger position. Again, you are limited by bumping into the first valve or the end of the string. But there is QUITE a bit of freedom there!

I think George McCracken started the work on this, Chuck Ward sure did a nice job getting it into production!!

Dave

Is it like this?

king.jpg

I haven't done that particular conversion. You would have to braze new attachment points to the stop arms, and it looks like the links would have to be very short, and you probably would have to modify the levers. Could be difficult. Maybe someone here has done it?

[greenbean]

I owned a 7B and would gladly buy it back if I could. It did not need a single mod.

[bassboneman69]

If the F attachment knuckle is damaged and not repairable what are thoughts on replacing w Instrument Innovations rotor(s)?

[Burgerbob]

If the F attachment knuckle is damaged and not repairable what are thoughts on replacing w Instrument Innovations rotor(s)?

If you used the tenor ones, might be a good choice

[greenbean]

Yes!

[bassboneman69]

If the F attachment knuckle is damaged and not repairable what are thoughts on replacing w Instrument Innovations rotor(s)?

If you used the tenor ones, might be a good choice

Not bass rotors?

[elmsandr]

If you used the tenor ones, might be a good choice

Not bass rotors?

Depending on the vintage, King maintained constant bore through the attachments. I.e. .562 for basses, not the .593 common in others. Part of what makes a king play like a king.

Cheers,
Andy

[jchiang9]

Slightly off topic but still related to the 7B. Does anybody know if the 7B copies out there have .562 valves or .593?

[psybersonic]

Slightly off topic but still related to the 7B. Does anybody know if the 7B copies out there have .562 valves or .593?

I've just bought a Coppergate for the princely sum of £100. The case was worth that amount. As far as i can make out the F internal diameter is about .59 so not a faithful copy of a 7b and the f trigger is below the bell stay like an 88h . Blows OK and the mid upper range is much more resonant than the Yamaha 613h I was using.

[Kbiggs]

I believe that someone, a long time ago in a galaxy far, far, away, made metal copies of the lever arm that holds the string. On my old 4B, I went through 3 plastic levers over about 10 years.

[psybersonic]

Oops ! a case of measure twice post once I measured the F attachment bore where the tuning slide fitted rather than the bore of the tuning slide itself. It is 14.3 mm or .562 inches . The slide however looks to be .547 . Mouthpiece insertion marks are the same as my 88h. Basically a large bore tenor with a Gb valve and a big bell .

[Burgerbob]

Oops ! a case of measure twice post once I measured the F attachment bore where the tuning slide fitted rather than the bore of the tuning slide itself. It is 14.3 mm or .562 inches . The slide however looks to be .547 . Mouthpiece insertion marks are the same as my 88h. Basically a large bore tenor with a Gb valve and a big bell .

These Chinese horns are all the same- the slides are .562, they are basses.

[psybersonic]

Oops ! a case of measure twice post once I measured the F attachment bore where the tuning slide fitted rather than the bore of the tuning slide itself. It is 14.3 mm or .562 inches . The slide however looks to be .547 . Mouthpiece insertion marks are the same as my 88h. Basically a large bore tenor with a Gb valve and a big bell .

These Chinese horns are all the same- the slides are .562, they are basses.

I've measured the inner slide with a caliper gauge it's 13.9mm inside diameter and 14.3mm external. I got it because a friend bought it online for her 9 year old as it was advertised as a Bb/f (the girl can't reach 7th position). No chance to return, caveat emptor. Gear4Music the original vendor advertise the spec as 14.3mm ID. They also do a large bore tenor so maybe the slides got mixed up somewhere along the line , however the bell and slide mate well.
The slide from a Yamaha 613h fits as well . We are only talking about 15 thousandths of an inch difference.
Will try out the Yamaha slide and see how it plays .

[heldenbone]

I haven't done that particular conversion. You would have to braze new attachment points to the stop arms, and it looks like the links would have to be very short, and you probably would have to modify the levers. Could be difficult. Maybe someone here has done it?

This is a 4B, not a 6B, but this issues are similar. I used a brass washer with 2 holes drilled to reverse the pull direction. I have some smaller ball joints that will go _under_ the washer to make it nicer and improve the angle of pull vs. the rotor bearing.

[Sweaty]

I have the Jinbao clone with a Sauer Brace, Brass Ark MV50 leadpipe in seamed nickel silver, and Giddings Mark I mouthpiece. The mods are worth more than the horn.