A topic for discussion of wooden jack replacements.
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Dear members,
I’m terribly late to reply to this topic. My profound excuses!
I had to replace several of my Hubbard jacks or parts of it. When I learned that the Hubbard company was no longer available, I found somebody willing to make exact wooden copies of the plastic ones.
Finally, I decided to replace all 4 registers (including the peau de buffle!) with the wooden jacks.
The good thing is that you don’t have to replace the lower registers. And also: the voicing is a lot easier!
Have a nice week,
Chris.
Hello Chris.
I had looked into doing the same… As you probably know, Jake Kaeser lists on his website all shapes and forms of wooden made jacks. However, when I contacted him about the older style Hubbard jacks, he rather recommended replacing the lower and upper registers and go with the simpler shape of jacks. I think in the end the price would have been similar. Regardless, the cost of such an upgrade unfortunately would’ve been comparable to, if not higher than, what I had paid for the entire instrument.
May I ask who fabricated your jacks? Was it Jake or someone else? Could you also elaborate on how the voicing appears to you to be a lot easier with wooden rather than plastic jacks?
I’ve also been toying with the idea of procuring a mini-milling machine and trying to mill my own jacks… 
Cheers,
r
Hi Chris,
lovely to hear that you are now the happy owner of wooden jacks!
Needless to say, I warned others that to change to wooden jacks in the Hubbard kit means to get new registers: I see you did that.
I am puzzled: why did you replace the jacks? Guess to fit quill plectra, for which the Hubbard tongues are inadequate of course. I have tested a wooden jack in my Hubbard: the action feeling is very but very subtly different, not worth the cost and trouble of a full replacement.
Did you have troubles with your original Hubbard jacks, supposedly made of Delrin?
Mine are fine after half a century.
Dear Robert,
My jacks were indeed made by Jake Kaeser with 2 modifications on my request:
- The hole for the axle which holds the tongue is drilled completely through. This makes it possible to remove/replace/repair the tongue. FYI: I had to do the latter on a dozen of jacks of another harpsichord were the axle was heavily corroded.
- The spring which pushes the tongue back is in the “French” way: a hole is drilled in front of the jack and comes out at an angle at the back of the jack. Very close to that hole, another one is drilled which goes between the “legs” holding the tongue. The reason is that I strongly disklike metal spring. This is a personal thing as I got so much trouble maintaining an instrument with metal springs.
Apart from that: quality, pricing and speed of production were all very good.
Have a nice week,
Chris.
Hello Claudio,
I did not change the registers. The wooden jacks are exact copies of the plastic ones including those for the peau de buffle.
Over the years I had to replace several tongues because the spring had a kind of “plastic fatigue”. These tongues were rather expensive (partly thanks to customs & taxes) and are no longer available at least no newly made. To give you an idea: one tongue costs as much as a new jack in wood.
At the moment I’ve only replaced a couple of jacks in each register to see if everythings works out fine (it does). When I have more time, I’ll do a big maintenance:
- Cleaning the soundboard, interior, keyboards.
- completely restring the instrument (no longer in steel)
- switch to wooden jacks
But don’t hold your breath. I’ve a waiting list for repairs so it won’t be in the first months.
Have a nice week,
Chris.
[quote=“Chris415, post:5, topic:1310, full:true”]
Hello Chris.
- The hole for the axle which holds the tongue is drilled completely through. This makes it possible to remove/replace/repair the tongue. FYI: I had to do the latter on a dozen of jacks of another harpsichord were the axle was heavily corroded.
Interesting… all the plastic jacks my 1967 Hubbard came with appear to have the axle hole reaching side to side. That has allowed me to use a punch and a voicing block to push out the axle when I need to replace a tongue. I designed my 3D printed copy the same way, and I had presumed Kaeser’s wooden copy would have had the same “feature” by default.
- The spring which pushes the tongue back is in the “French” way: a hole is drilled in front of the jack and comes out at an angle at the back of the jack. Very close to that hole, another one is drilled which goes between the “legs” holding the tongue.
Sorry, I’m unable to picture that! Would you have a reference or a figure that describe such a type of “French” style of tongue? Thank you!
Cheers,
r
Hello Chris,
If it is a Hubbard kit, and unless you restrung it calculating string alloys and gauges for A=392 and probably less, you will not be able to get rid of steel completely. Some comments:
- Hubbard based his 1960-70 kit on a Taskin which, according to my calculations, was meant for about A=400.
- However, using steel, Hubbard was able to sell his non-transposing kit for either A=415 or A=440.
He also had to use things like Beryllium copper for the brass-steel transition, otherwise brass would break! - Steel did not sound well in the treble, and for this reason Hubbard increased the scaling there!
- Now that we have iron, we can use iron instead of steel .014 and steel .012. This not only sounds subtly but noticeably better, but also produces an audibly seamless transition from Red Brass to Yellow Brass to Iron to Steel: blind tests and nobody notices the changeover.
- However, due to the increased scaling of Hubbard (over the original meant for A=400!), iron will break in the extreme treble for A=415, or even throughout the treble range for A=440. I got this result with calculations, which I verified with experiment inserting a few iron strings in the treble range: a few broke, the others did not sound better than steel, but worse!
All the best
Claudio
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Hi Robert,
This video explains the concept: https://www.youtube.com/watch?v=p1nE7bBIdD0
It’s not the tongue but the spring.
Hello Claudio,
What you say is true when using Rose or Birkett wire. When using Stohlberg messing & West-Fälischen Eisen 99 (sold by Vogel) you won’t need steel at a pitch of a1 = 415.
Regards,
Chris.
Hi Claudio,
Le 21/06/2023 16:42, Claudio Di Veroli via The Jackrail Ă©crit :
- Hubbard based his 1960-70 kit on a Taskin which, according to my calculations, was meant for about A=400.
- However, using steel, Hubbard was able to sell his non-transposing kit for either A=415 or A=440.
He also had to use things like Beryllium copper for the brass-steel transition, otherwise brass would break!- Steel did not sound well in the treble, and for this reason Hubbard increased the scaling there!
When did Hubbard change the scaling of his Taskin kits, and how can one
tell if an old kit has the original scaling or the modified one?
Thanks.
Letter I got from Frank Hubbard, dated October 1974: “Our instrument has a lengthened (or distorted) treble scale which we settled on because it makes the treble more singing (i.e. sustain longer).” He gave no numerical details on this. Since so many small details that according to Hubbard were based on Taskin were only approximately so, this does not rule out that the whole shape of the bridge was slightly modified, not just the treble.
He used steel, which needs more tension to sound right, while conversely iron tends to break with a lengthened treble scale.
To know for sure, for kits after 1975 I would say that one needs to take measurements and compare with scalings of the Taskins 1969, or supposedly Taskin 1970 for these later kits.
To make matters worse, many valuable French instruments had, at some time after their last ravalement, their bridge unglued and re-glued in a different position: sometimes it is possible to say with certainty whether this happened or not (the Goermans-Taskin in Edinburgh shows convincing negative evidence), in many others it is not known at present, and Boalch catalogues are mostly silent on this important detail.