Organ Pipe Making observations

[Brian Daniels]

Some readers may have seen the video clips on 'Youtube' of Martin Pasi's pipe making.
I think his relaxed and gentle confidence is inspirational to many aspiring to the craft.

There a few thoughts of mine which may be of interest.

Metal casting - He uses a thermocouple and voltmeter or equivalent method of determining the signal to
pour. The traditional way of looking for pins and needles is difficult and generally when they appear
in bulk it is too late.  If that happens you have a lot of planing to do if it's plain metal and if it's
spotted you have goose pimpled spots!
I have found that a good early warning is when the metal starts to cling to the
skillett when the metal is stirred. Metal is poured in the plastic state which has only a few degrees C  band width. By defining the temperature for the particular alloy (small contaminants will alter the pouring point) in terms of the junction voltage of the probe, the casting process is easier to replicate.

Prep. and cutting out - Martin uses a guillotine, being a  largish workshop, and not a cutting hook
which I used in my small outfit. He then paints the whole work piece with traditional size, cuts out and trims the edges with a block plane putting in the jointing chamfer at the same time. Solder candle is now applied before
rounding up. (Interestingly, his block plane was identical to mine!).
This is an interesting departure from the common practise of rounding up, applying size to the joint area only and scraping clean the joint with a three corned pointed scaper. I have found that Martin's method gives rise to a better surface for solder wetting that by using the scaper since there is always a tendancy for some occasional chattering of the surface. If one can ignor the cost of the superfluous  sized area that is. Also, there is a need to wash clean after soldering when size is applied to the seam joint area only.

Rounding and soldering - Rounding up is done in the obvious way ie by beating in a leading edge and roll over on the bench.
Soldering is done here with an electric iron; now common place in pipemakers' workshops.
However the is no disputing the fact that, thermo -dynamically, the large square externally heated bit is superior even if less convenient. Rather like comparing a large wind reservoir with a schimmer. Electric irons require some form of control and even so the technique is quite different. I have two; one for pipes up to about 2ft which is a closed loop tool keeping the bit within about 5 degrees C. Obviously one cannot take more heat than that the iron can regulate in a timely manner. The other is an open loop ie it uses an energy regulator similar to the controls on an electric cooker
Martin tacks and fills the joint and wipes the work piece clean. The same procedure for foot and body.
The work piece is trued up on a mandrel after soldering.

Flatting and fitting the languid - Flatting is done after marking the mouth profile by using a burnisher and
conventional flatting tool to both body and foot.
Martin then trues the ends of body and foot with a bevel edged chisel ( and not a block plane ) and then cuts a piece with the flue bevel planed in and fits it to the foot flue edge; tacks it . He then trims round with a pair of side cutters. He then solders around the languid by melting the scrap around its edge.
Body and foot are soldered together after checking squareness.
I think this is enough but there is more....

Brian Daniels.

[Colin Pykett]

Yesterday I mentioned Jonathan Lane as an example of an organ builder who is also professionally qualified in music.  I hope my good friend Brian Daniels will not mind too much if I point out to those who may not know that the same applies to him.  It is rare to play an organ, as I have, in the presence of the person who built it entirely from scratch, and that includes casting the metal for the pipes.  Then to hear him play it as only an ARCO etc qualified person can, and his own compositions as well.  The forum is fortunate to have such members.

One of my favourite digitally-simulated stops is a quintaton made by Brian in this manner, which he kindly allowed me to sample electronically.  I can play on it for hours!

Colin Pykett

[revtonynewnham]

Hi

Interesting observations, Brian.

The Bradford Organists' Association had a demo of pipe making a couple of years ago - obviously in a church hall, casting & planing metal was out of the question!  Other than that, Terry Shires made an embossed middle-C diapason pipe from flat (but pre-cut and embossed) metal - added the foot & other speaking parts - electric soldering iron, but he did mention his preference for the traditional gas iron - and following that, David Wood voiced it.  The finished pipe, mounted on a stand made by one of our members, is a prominent feature in our exhibition.

We also had a visit to the pipe-making works - but I missed that (and other things) due to being in hospital at the time.

Brian Hirst's book "Just a Box of Whistles" "Secrets of the Art of Organ Pipe Making" is also an interesting read - though I doubt anyone could actually make a pipe just from reading it!  Private publication 2001 ISBN 0-9540697-0-6

Every Blessing

Tony

[Brian Daniels]

Thanks Tony.
Yes, Brian Hirst's book is interesting and informative and goes into a lot of detail but it is impossible to cover everything. You can only make a pipe by doing it! That sounds daft but it's a bit like reading about
French polishing and then trying it out and expecting it to work first time. Pipe making is a very tactile craft and there are many nuances which are never fully documented; not because the craftsman (unisex here) is secretive but because they are simply overlooked.

Regards.

Brian Daniels.

[Jonathan Lane]

Thanks to Brian for sharing his considerable knowledge of pipe making, I play on some of his pipes regularly, and a delight they are.  His insight is valuable, as are the videos of Martin Pasi which are very relaxed and easy.  The manner in which he makes the pipes and discusses his approach is an ideal tool in the education of pipe makers, however Brian is quite right in saying there is nothing like the actual practice of doing it!  Terry Shires too, is a wonderful exponent of the art and when we went round his workshop was very pleased to show their work in some detail.  Thanks again to Brian, fascinating stuff!

Jonathan

[KB7DQH]

When the opportunity presents itself I should go visit Martin Pasi's shop... as it is less than two hours by motor vehicle from my residence :o 8)  and the shop of Paul Fritts is even closer ;D ;)

Eric
KB7DQH

[revtonynewnham]

Hi

I find any true craft fascinating.  I have a friend who makes (mainly gold) watch cases - among his tools are a pair of bow lathes from the 17th @18th centuries and a collection of rose-turning machines.  He rarely measures anything!

One thing I meant to say earlier was that in his talk, Terry mentioned the lead ban issue, and said that he had actively investigate alternative materials, and had even successfully devised a way of making pipes from aluminium!  I got the clear impression that he's more than happy that traditional pipe metal remains available!

Every Blessing

Tony

[Brian Daniels]

Terry investigating aluminium is quite scary! The EU is responsible for a raft of un-joined-up legislation and the lead ban was one. I wonder if we hadn't all got together on this what would have happened.
To divert for a minute. As a boy of ten I bought an ounce of Mercury, four ounces of Copper Sulphate and, wait for it, four ounces of Sulphuric Acid! This was in 1945!! At 76 I can't get any of this now except perhaps on the Net.
We must be alive to any attempt to ban materials essential to  specialist usage. I don't think we have heard the last of this sort of problem.

Brian Daniels

[David Pinnegar]

Dear Brian

Thanks so much for your contribution. I hope that my starting the thread on how pipes speak might have inspired you . . . and any insight into getting pipes on speech, on measuring pipes to predict their pitch, on the various parts of the pipe and how variations of design can alter the speech and tone would be particularly interesting.

The other night at Kingston, Matthew Copley gave an brilliant tour of the Frobenius organ there and in addition explaining the constraints and advantages of tracker action and its effect on the architecture of the instrument as well as the design of reed pipes. He mentioned for instance that on the Continent the end of the shallots are domed rather than squared which causes other harmonics to be introduced. Is this what we hear in terms of inharmonic harmonics, which cannot effectively be reproduced electronically?

He also mentioned the effect of the tuning of the resonator to the reed and how shaving off the top of the pipe from overlength to underlength changed the effective vowel sound from an ooo to an aye (if I have that right) . . .

What is concerning is the fact that there are no courses now where prospective craftsmen can learn about making organs. Matthew used to teach the course at Merton and from his presentation last Monday, he must have been brilliant there.

Best wishes

David P

[Brian Daniels]

Dear David,

The actual speaking length of a flue pipe is less than half wave length by an amount approximately equal to twice the languid depth or about 1.5 diameters  depending on scale, mouth width and cut up (Cavaille- Coll says 1.6D according to Audsley). I have attempted to verify this mathematically on the basis that the soundwave has to 'bend' somehow through 90 degrees. Soundwaves don't bend as such in these situations but they do reflect and one can empirically trace the reflected path length from flue to back of pipe to upper lip and onwards out to the pipe end. This however does not stand the test of acoustic behaviour of the short distances involved and the wavelength of the particular note. My equations are simple but messy and long and not reproducable here. Reed pipe resonators are also shorter than the equivalent half wavelength but here the resonator is a truncated cone by virtue of the entry diameter to the socket. If you consider the full cone, ie continuing to its apex; equate this length to the half wave length and then deduct the small portion form apex to socket entry the resulting length is about what you get in practise. That is bottom CC is about 7.4ft long instead of 8ft very approximately. Again this is empirical and assumes the origin of the wave is the apex of the cone ie an imaginary point below the shallot . I have measured several reed pipes to confirm this and made resonators using this formula.

Codetta: I can see no reason why domed shallots shd. produce irregular harmonics, which, by definition would surely be objectionable. I can see that the aerodynamics of the tongue could well be affected but to prove exactly how and why would be beyond straightforward physical analysis and would require a trials project in my opinion.

Regards.

Brian D.

[David Pinnegar]

Codetta: I can see no reason why domed shallots shd. produce irregular harmonics, which, by definition would surely be objectionable. I can see that the aerodynamics of the tongue could well be affected but to prove exactly how and why would be beyond straightforward physical analysis and would require a trials project in my opinion.

Dear Brian

Thanks

There's lots for us to get our teeth into in your description but I hope that Matthew might tell us more here about the domed shallot ends, if I understood correctly. He was saying that the practice is prevalent on the Continent and certainly, if they are an example of this, the Moucherel reeds at Albi restored by Formentelli and the reeds at St Maximin have an "edge" to them which to my ears sound very metallic, in an inharmonic manner in the nature of the inharmonicity of piano strings.

Unfortunately I did not video the part of the talk in which he referred to it, but certainly it's a fascinating subject.

In the early development of trying to get the Hammerwood instrument to give a sense of the baroque continental reeds, I tried adding some inharmonic content, or detuned 2nd and even harmonics http://www.youtube.com/watch?v=tTaAdHOA8s0 and the technique excited a retired voicer who worked at Albi for Formentelli specifically to contact me and encourage my research and http://www.youtube.com/watch?v=6cL8QDLv8vM and http://www.youtube.com/watch?v=bi2pdYou-Rs is as far as I got.

Clearly in terms of pipes, the geometry of the resonation chamber which is the shallot as well as the resonating pipe as tuned amplifier, and its length, will have an effect upon which tuned harmonics or inharmonics are chosen to be prohected.

Best wishes

David P

[KB7DQH]

What is concerning is the fact that there are no courses now where prospective craftsmen can learn about making organs.

You will have a lot of explaining to do to the following folks at Oklahoma University :o :o :o ;D :D ;)

http://aoi.ou.edu/

According to their last newsletter, they graduated one student with a M.A. in Organ Technology 8) 8) 8)

Eric
KB7DQH

[David Pinnegar]

Le travail de Moucherel était sans doute remarquable mais c'est Isnard qui vraiment porté le choeur des anches à la qualité qu'on a retrouvé aujourd'hui. C'est lui qui a ajouté le clavier de Bombarde et retravaillé les trompette du GO.

Je peux vous donner des renseignements précis sur la manière de travailler ce genre d'anches. Il faut suivre rigoureusement Don Bedos.

Les facteurs contemporains (surtout les anglo-saxons) n' arrivent pas à désapprendre et à oublier les techniques romantiques de l'intonation des anches. A la condition d'être soigneux dans le travail, et de respecter certaines observations, c'est relativement facile de reproduire ailleurs une telle palette sonore. C'est aussi plus efficace et moins coûteux que d'essayer d'imiter par des procédés électroniques. La distortion est infiniment trop grande.

Avec les harmoniques impaires, il y a une telle énergie libérée que le corps tout entier entre en vibration, pas seulement les oreilles. Les anches française du XVIIIè n'ont rien à voir avec Cavaillé-Coll.A Albi, on se sert de la superposition des harmoniques impaires pour développer des résultantes graves. Cavaillé-Coll fait le contraire, avec une pression double!!!

[Brian Daniels]

David,

This domed end business could well be similar to the beaked shallot which also produces  an edgy tone. I think its is down to the aerodynamic flow from the free end of the tongue up into the shallot.
I remember when I made my Regal 16(just 30 brass tongues as striking reeds in a chest) for my little chamber organ I found that the direction of air flow from the chest via the reed to atmospheric pressure was critical. The maximum amplitude occurred  when the air entered the free end of the reed. So it seems that the air stream dynamics plays a part. I still have reservations about 'inharmonics'. These are things one tries to engineer out; not in.  I would suggest that the rasp (for want of a better word) is possibly an increase in power of the upper harmonic series as a result of improved air flow brought about by the end of shallot design. The end being the critical entry point of the wind. A smooth dome interior is less likely to cause as much induced turbulence as a flat or bevelled end and therefore represent a more efficient path for the wind; hence more noise. Don't motor horns have domed shallots? I seem to remember something like it does.

Brian D.

[Brian Daniels]

I forgot to mention  that a reed resonator is effectively a tuned auto transformer. That is, it transforms high pressure low volume velocity to low pressure high volume velocity. All relatively speaking. There is no power gain in an acoustically passive device. It does magnify volume velocity to suit our ears at the expense of pressure.

Regards.

Brian D

[David Pinnegar]

I forgot to mention  that a reed resonator is effectively a tuned auto transformer. That is, it transforms high pressure low volume velocity to low pressure high volume velocity. All relatively speaking. There is no power gain in an acoustically passive device. It does magnify volume velocity to suit our ears at the expense of pressure.

Dear Brian

Thanks for all your brilliant insights.

In respect of the transformer action of the resonator it's interesting to hear in Matthew Copley's introduction to reeds http://www.youtube.com/watch?v=r6pfY4ZYw1k the flattening effect of putting the resonator onto the reed. It's loading the reed, taking power away from the vibration of the reed, so lowering its pitch - or is it simply adding the mass of air to the resonating system?

Earlier on you mentioned that the waves don't bend around corners but are reflected. Is this really so when one considers the orchestral French Horn, which would be most complex to analyse in terms of a process of continuous reflection. When us horn players take a hose pipe and blow it similarly, there is no difference between the straight hose and a bent hose in terms of pitch or even tone. Is there a difference in analysis between a high pressure variation of a travelling wave in a pipe narrow compared to the length and a low pressure variation wave in a section wide compared to the length.  A wave might travel as a simple pressure pulse when the air "feels" as though it has nowhere else to go and thereby be unaffected by bends, but when the air is not compressed so much within a wavefront, it may behave as a reflected wave . . .

Colin may have an insight here . . .

Best wishes

David P

[Brian Daniels]

David,

You are absolutely right re. French horns etc. I did say 'in these situations' ie a sound wave in a tube of 2ins.(say) with an abrupt termination at the languid. In fact one can imagine a curved tube consisting of and infinite no. of  plane reflecting surfaces. When a sound wave meets a high impedance surface it is deflected to a degree depending on its orientation and substance.  Wave length and diameter of tube are important as the old (now defunct) cube bass testifies. As you say Colin may wish to put some meat on these bones!

Brian D

[AllenJ]

I've been watching several videos of craftsmen making flue pipes for organs, and there is a tool that seems to be commonly used to solder the seams.

My first guess is that this is some variation of a soldering iron, but I'm unable to find anything resembling those tools when searching for soldering irons.

Can anyone tell me what the proper name is for those tools, and possibly where one might obtain one of them?  (if such is even still possible???)

Thanks

[revtonynewnham]

Hi

Heavy duty soldering iron is what I've sseen used (demo by Terry Shires).  Maybe the bits are specific to the trade.  Terry Shires would probably be able to tell you where they're available - or take a look at the Laukhuff catalogue - http://www.en.laukhuff.de/assets/0.pdf  P.23f cover soldering irons.

Every Blessing

Tony

[AllenJ]

Thanks.  I did contact Shires Organ Pipes through the contact form on their website, and got a response from a gentleman named Terry Shires.

He indicated that they were indeed soldering irons, but probably specific to the trade of making organ flue pipes, and as such, they were only available to his knowledge, from either Weiblen or Laukhuff.  Laukhuff has a distributor in the USA, who sells 120 volt versions of them too (I'm in the USA too), so that turned out to be a real gem.

I may never become a master organ builder, but I'd sure like to try dabbling in that trade as a hobby, and the wife has already accepted that our next home is supposed to have some space with ceilings to house 32' pipes...  ;)  Even if I have to build the house myself first!

I've also just recently discovered this forum this past week, and I expect I'll be back from time to time, especially as I make progress on my builds, but I must say, your forum verification process with the questions about organ knowledge are a bit scary and daunting for a novice, and were it not for Google, I'd have never even been able to join here - Is that the intent?