renaissance recorder, tenors and larger bore profile - created 06-01-2010

Emery, Dana - 06/01/2010.11:34:43

The bore profiles of smaller recorders (alto, discant, kleine...) have different design concerns because of how they relate to the size of human hands, I ask that we restrict this discussion to the larger instruments.

Have been reviewing the instrument dimensions published by the Vienna Kunsthistoriches Museum (Darmstädter, 2006). When there is no key, these are in one piece; some are also in one piece when fitted with a key, others are in two pieces socketed at the fontanelle.

Several general profile schemes are noted, Adrian Brown discusses them in the german text (which I am in the process of translating).

One general observation prompts me to ask this here tho, the general trend is for the head of the instrument to have a decreasing bore (which makes sense at the block), and this is seen in a gross way; but in detail, the portion just 'south' of the blockline swells out a mm or two on all instruments.

My concern is how to fabricate such a bore. I very much doubt the wood at the block shrank any more than the wood lower in the head joint. the generalized profile suggested by Bob Marvin uses a drill for the minimum diameter at the choak (vicinity of holes 6,7), and three reamers, one nearly a drill for the block and upper part of the head, another stronger taper for the middle of the body, a third (reverse) to open the foot and form the bell.

Bodgers (chair makers) took a portable lathe into the woods and turned green wood spindles; these were assembled to legs socketed by a 'spoon' bit. The socket resembled a modern incandescent light bulb in section (eg, the entry hole was smaller than the inside); the green wood of the leg would shrink around the fire-dried wood of the spindle to lock the joint.

A bodgers spoon bit would have been much shorter than our reamers and more suited for 'swelling' the profile.

Dana ,

As I have yet to measure this I feel most reproduction makers do not copy this aspect.

To recreate this, without long armed spoon bits, one can do spot and overtone specific bore enlarging with small bore scrapers attached to wood dowels. I have successfully used this method to work on the third octave in one piece bamboo flutes.

The appearance of 'pockets' of wide bore areas do often appear in historic instruments and can either be part of the voicing and refining process , or the unevenness caused by employed methods of construction. Renaissance large bore originals do not have the polished bores I see on reproductions.

Having not been to Vienna for first hand experience this is the best I can offer. You can try and email Brown.

The catalog has a consistant description of each item, photos show front, rear, fontanelle, cap, ketwork; this book is a must for any one considering replicas, especially of bassano-made instruments; price is not huge for what you get, tho the text is all german. A least two internal bore profiles are shown, often several; distinguished by color.

I believe methods are discussed, but since this is in german which I have not yet translated I cannot say; I know Bob Marvins involved preset guages. I have noticed reviews are in FoMRHI and other publications. Not clear if blocks were removed for measuring. Bob Marvin and other researchers (Adrian Brown for one) are mentioned when multiple sets of lines are shown, presumably these show all the measurements known to the museum.

I would have expected the block to limit shrinkage as you say, leading one to expect the bore at the block to be larger than that below, with a step at the blockline. What is seen is the opposite.

Back to the original question, what does a 'pocket' in the head joint do for voicing?

I will get the Vienna stuff , thanks

I have used a pocket in soprano renaissance bore instruments and it has helped extend the range. The pocket started after the block, as you say, and ended an inch before the thumb hole. It was initially a mistake but found without it I had less range. I'll write more when I get the Vienna info. I suggest making the instrument without it. Are you going for one piece replicas?

The topic of ovalness is concerning an observation from older instruments. Is it not possible that the bore is not just shrunk in one direction but slightly expanded in another? Also more probable on older instruments I have inspected where moisture resides in a bore the wood grain raises , feathers and eventually wears away. This of course is very true of bassoons with their turnabout bores. I've had to rebuild bores at this point.

I'm missing something here. While I do undersand all the description, I can't understand why it would be necessary to have the block cavity actually smaller than the immediate area in front of it. Sure, have the first few cms of the bore wider by a mm, but what difference does it make if the block is slightly smaller? I'm referring to Stephen's remark about the pocket adding to the range. Surely a sligtly larger bore at the top, with an equally slightly larger block would achieve the same effect?

Yuri,

Oh, I know about spoon bits. There used to be a kind of variant, made by some chair bodgers. It consists of a normal spoon bit, with the tip ground back to a kind of oval. That is, the cutting part left untouched, and the area immediately behind, instead of left straight, rounded off, withy a bit of grinding into th straight sides, leaving a kind of half-egg-like end, with the shaft after that continuing untouched. What it enabled to do is once the initial bore was done, shaving an oval hole, with the opening slightly narrower than the inside. The whole point of course being that the dowel was also turned with a slight know on the end, then dried more than usual, hammered in, and once in, swelled to fill the cavity. After this treatment there was no way to get it out again by pulling.

Useful things, spoon bits...

Sorry, that is a slight knob on th end, not a know on the end.

Yuri, you have 30 minutes to edit your posts, use the "Edit" button in the message header.

Dana ,

Back to the pockets, specifically which ones? I see a lot of variation. My favorite is the Bassano alto with the even sized fingerholes and an incredibly wild pocketed bore to make it work. I have done this before and found I had more control over the timbre.

I am convinced that the pocketing was done intentionally with a spoon bit.

Again I feel that the possibility of the block being installed and the holes being drilled before the bore was completed has a good argument for it. Opening up the head joint effects the octaves among other things. The old bore test by Alex Lorenzo was to put a recorder mouthpiece on to a section of garden hose. Next squeeze the hose at various places to understand the effects.

one also has to beware the pockets caused by worm...

Yes, preset feelers are not a good way to see them, perhaps BM omitted some details which he was unable to determine accurately. No particular pockets, i was surprised at the existance of any of them, the wooden body reamers I have been using dont do that; tho spoon bits and riffler files (floats) could.

I agree with your surmise on the order of building. I know when I made my first tenor I deferred taking the bore to its final shape until I had the block in place and initially voiced; just makes sense to go from the gross to the fussy.

About going for one-piece; back when kings and prices supplied players with chests of instruments, that was a workable concept. Things have changed, now players like to have their own, and that means some accomodation for tuning is necessary, a thread-lapped head joint is easy enough to do.

When I chose to make renaissance consort instruments I chose the Kynseker set as it was the first to have tunnable headjoints.As I was able to study the original. However I used the Marvin info for bores. I as well made the basset in three pieces for ease on my part.

Modern wooden as well as metal body reamers do not make pockets. I have a good many tools aside from my limited supply of spoon bits that can create pockets.

Did you notice the number of recorders with blocks with the heart of the wood in the center?

Stephen, the "heart of the wood in the center" has been perfectly normal practice in folk pipes of all kinds in at least E. Europe well into the 20th century, and for all I know is still a normal practice in quite a few places, like Romania, Albania, Bulgaria, and oter -ania-s. The way I see it, folk instrument makers got onto the idea that some woods shrink less than others a log time ago. However, the refinement, meaning the particular cut of the wood, must have been a bit slower in the coming. Or simply it wasn't convenient enough, or important enough to take into consideration. Well, back in the 16th century quite possibly the same attitude prevailed. I know, the best 16th c. instruments are certainly not the same as 20th c. folk instruments. BUT. Instruments surviving from the 16th c. are most certainly the jewel in the crown. Only the very best survive, and even in those there are a , well, quite a number of very questionable practices. Shortcuts of every kind imaginable. And yes, that includes using blocks with the heart in it stil...

Yuri, I have as well seen this in folk instruments. It is hard to consider a renaissance bass recorder in one piece as having anything to do with a short cut due to the time consuming task of construction. It could be after market repair, or blocks made by players. The 18th century recorder is definitely of greater refinement in this regard. But Your point is well taken , we weren't there and any number of reasons could have been in use, and it is foolish to be bias.

The master is about the only one in a shop who gets to take his time doing anything. Journeymen, prentices both are under time pressure, so unseen surfaces will receive minimal decoration or indeed clean up of any kind. This is seen in wardrobes and other furniture as well as the interiors of harps and keyboard instruments - saw marks, axe scoring, sapwood, loose knots, pith, even bark.

But, one also sees deliberate grain orientation in joinery of all kinds - houses, boats, furniture; sometimes for strength, sometimes for wood movement; consider the use of crooks to take advantage of naturally swept grain in angle braces, fittings for rigging, and rowlocks. A much wider variety of materials was explored historically, consider todays attempts to buid replicas of viking era boats, the design and mounting of the steering oar still has mysteries for us, nylon rope yielded to the traditional wythy; computer analysis helps to refine the airfoil-like shape of the blade itself.

One has to consider that suitable wood was not always available. SAM 160 has a bell diameter of 77.1mm, the fontanelle barrel is even larger (88? memory fails). I intend a body joint just above the fontanelle, so about 20cm of foot will require 12/4 cherry, which I will glue up for my prototype as I only have 8/4 cherry on hand.

What springs to mind is the fact that we seem to view the makers of the past in more-or-less our own image. As a kind of master craftsmen, devoted scrupulously to the minutiae of the craft. And, indeed, no doubt there were quite a few of makers like that. Well, there also were the ones of the other kind. After all, guild systems existed in some, but by no means all places across the centuries under discussion. There were all those jobbing general woodworkers making an extra pound, krone, guilder, peseta, etc, etc, by churning out an instrument. I don't mean only woodwinds, but any kind going. Actually, probably woodwinds would have been rarer than others, given the very specialised knowledge required. Talking about bark, well, about 15 years or so ago an 18th c. French harpsichord came up at an auction in France, which was distinguished by having some of the struts made from spruce of the very outermost part, with the bark still adhering. What I mean is that while truly refined instrument making is indeed truly refined, there is a LOT of instruments from the past that are not quite as much refined as all that. AsDana says, apprentices have some questions to answer, so do journeymen.

By the way, there are some dozen or so Latin American clavichords surviving in various collections. Do you think they were made by some Latin American equivalents of the Ruckers or Kirkmans? I personally doubt it. I'm fairly sure that the local all-round carpenter churned out one when asked to. The same way as the Tarahumara indian general woodworker will make the odd (amazing) fiddle today.

Almost every male makes his own fiddle as a right of passage in the Tarahumara culture. People who work with their hands , yet not by trade woodworkers.

There is much to be studied concerning Latin American early Luthiers. Clavichords, harps, organs, woodwinds, and numerous variations on the guitar family. One must as well consider the trombones of the sixteenth and seventeenth centuries. A Ruckers or a Bassano family has yet to surface from the past in English literature, but luthiers of skill did exist and serve the colonial fervor. I am sure much untranslated research exists in Spanish and Portuguese.

After all if we follow what history accurately presents rather than the mythology that evolves over time we see that Stradavari was actually an apprenticed furniture maker rather than a trained luthier. And without adding anything to the mystique it seems evident his skills in carving and inlaying are what got him involved in the violin world.

As all levels of musicians existed in the past, or so the literature presents such, so did all levels of makers, as we see from museum archives.

The woodwind is by no means more difficult to make than a string instrument, just different skills, successful amateurs just copied something that was successful.

But concerning these large bass recorders, I do not doubt that the apprentice was employed to blister their hands on boring the hole, as a matter of fact we do have a famous woodcut of such. However that mouth must be fed and housed at a relevant expense. When we look at these large instruments we see within each variation of refinement. That which is important is refined the rest less so.

Hello Dana

Your original question was how to make special purpose "shell reamers" for large scale Recorders?

Here is a site for that purpose (it used to be in the MIMF links?)

http://www.recorderhomepage.net/tools.html

If you have ID measurements, these turned wooden shell reamers with adjustable/replaceable blades are easy to make. I use them for making many types of ducted flue woodwinds.

Another option is to make your bore blanks in 2 parts. The internal bore is made in stages with a router and then blended into a conical half-bore with scrapers. The 2 halves are epoxied together and a final sanding is made with a conical sanding stick. I prefer this method for large woodwind bores.

here is a useful video showing a reamer in use.

http://www.youtube.com/watch?v=WiSW6LPchSc

Note: The angle of the internal bore adjusts the frequency of the overblown harmonic frequencies. This allows the Recorder Maker to tune the upper registers and avoid flat pitch. Flutes do this by adjusting the headjoint cork.

Hello Thomas.

No. That was not my original question.

If you examine the measurements published in the catlaog I mentioned you will notice that the bore profiles often have 'pockets' which are imposible to form with a reamer. Bob marvins dataa was not sufficiently detailed for these pockets tobe easily seen. One can make a pocket using a spoon bit or a riffler file, or by pooling shellac on either side. My question related to how deliberate such pockets were, could they be artifacts of aging? are they useful in design?

I am well familiar with wooden bodied shell reamers from Trevor Robinsons work and my own building. I have a model of SAM 150 using wooden bodied reamers which is a satisfactory instrument at a=440. I have had difficulty making a second copy using the same tooling. IMHO wooden bodied reamers are not satisfactory for production work on smaller instruments, because of twist and shifting of the blade they are incapable of making two instruments with the same profile, a necessary preliminary step to use interference beats in adjusting the design.

Sadly, the library I get access to the internet from is blocking that website.

"stradivari ...apprenticed furniture maker..."

Medieval systems for ensuring public confidence and ensuring some form of checks and balance against sharp practice were many and various, but generally included a formal setup sutch as one or more a guildhalls where certain trades were regulated and complaints could be brought and adjudicated. The common trades were easily covered - mercers, butchers, grain-dealers, carters. Uncommon trades were not always covered directly, especially those which were new or had but one member. Instrument-makers are uncommon even today, they might be placed with woodworkers, or goldsmiths with about equal relevance.

Printers provide a case example of how new trades were dealt with which has been better studied.

It just occured to me that the pockets could have (if deliberate) been made another way. That is when the pilot bore is complete, and only the fine reaming left, to wet the area that need to develop the pocket. Then immediately proceed with the reaming. When all is done, the wood in the wetted area will shrink back as it dries, creating just that kind of irregularity. It only would work if the reaming process takes off only a small amount of wood, of course.

Very interesting proposal Yuri.

On studying the text and bore grafts Dana presented Yuri's idea is not without merit and might work .

However from the iconography of woodcuts and prints of musical instrument tools of the vintage of these early recorders, the boring tools, or reamers, show a tapered 'spoon' shape that with misuse or intentional use can easily pocket a bore. When fixed hole placement and size is an issue pocketing as well as massive undercutting and drilling holes at angles are useful and proven approaches.

I've made cheep spoon bit replicators from grinding used spade bits. Care must be taken so they don't chatter, such as manual rater than motor powered. However if the spade bit is ovaled and powered by a drill and put on extenders as is necessary on such a large instrument I know from experience it will pocket. The problem then is to figure out how to smooth out the pocket.

Yuri, I understand you, but i wonder how well the water application can be controlled using renaissance technology. I suppose a long small hollow reed would do, perhaps filled with a thread wick to slow the flow. The instrument would have to be held horizontal and rotated while water is applied at a rate to be absorbed. One has to expect the application zone to expand as the wood pores will wick the water. Each wood will have different behavior this way (Box, Maple, Pear, Plum).

I use a similar technique to expand the area around an accidental dent before finishing, steam helps, and sometimes I will use a fine point to prickle the area and get the water deep, under the bruised wood. Severl thousands of an inch of rise can be had, certainly enough for a useful pocket.

I would expect the amount of raising to be sensitive to grain orientation.

One wonders if normal breath moisture and not unreasonable workers impatience caused this effect in the head joints of every instrument during its initial voicing; or if the Bassanos employed air reservoirs such as are used in pipe organs for voicing new pipes.

Stephen, while contemplating boring the more challenging bores of a dulcian, I have always thought that the initial drilled bore will of course drift, and to allow for this, the down hole would be drilled first, its exit hole locationo will then need correction, and this could be done grossly by making the taperd reamer with a non-cutting pilot small end which will follow the drilled hole, the cutting edge can then be pressed sideways to drift the bore in whatever direction is needed to make it concentric. The upper bore is then done similarly, correcting from above (its large side).

This sideways drift, using a long cutting edge will not cut a pocket.

However, if the reamer is shorter than the profile it is making adjustments to, then a pocket can be formed, given considerable care as one will be taking swipes, leaving a shape that will resemble the inside of a rough barrel.

You might consider the later as being a reason for what you see. Many of these large recorders were in one piece and I find it highly unlikely they were reamed with a single edge the length of the body.

Before I started using gun drills I had a great deal of wander, but never found it necessary to favor one side or the other as by the time the reamer reached the far end all was trued out. The trick is to start with a large enough piece of wood.

The larger the instrument the more complex the bore it seems, the step-bore altos (SAM 133, 138) are quite simple, as is the one step-bore tenor (SAM148). Of the choke-bore tenors SAM 150, 151 seem simplest to me.

By "Pockets" I assume you mean "Bore Perturbation Techniques", ergo, increasing or decreasing the internal bore diameter just above or below a tonehole (?) This technique changes the air column velocity in the immediate area of the tonehole.

This can be done in many ways. I prefer to make bore sections in 2 halves so I can easily undercut the toneholes from inside. I then epoxy the 2 halves together. The seam is invisible and stronger than the wood itself. This technique can create even extreme variations of internal bore diameter (if needed).

There are other alternatives to Bore Perturbation though. The Oboe uses increased tonehole depth. The Tartold Dragons (modified Rackets) use a spiral bore etc.

Maybe I don't understand "precisely" what you are trying to do. Can you give a more detailed explanation?

Exploring design in the context of historical technology.

Yes, splitting the body and carving the bore is easier, it was commonplace for cornetti, lizards, and serpents; and allows a curved bore to follow natural grain. Difficult to test and redo unless using hhg (not wrapping until done), so your design has to be mature. I dont consider undercutting a sufficient argument, historical makers were able to devise tools to do undercutting from outside, I have had no trouble on the sizes of recorders I have worked with so far.

The recorders head joint has enough risk of being split from the pressure of the block when the wood is intact, as well as the shock of being tapped out for maintenance; I will leave the strength of materials and glue joints aside, just recall that some woods (especially rock maple) are classified as 'poor' for glueing because of density. I am familiar with quality epoxy and know the issues in using it from my commercial work refurbishing pianos, I dont like working with those chemicals, and the expense of keeping fresh stock is not acceptable.

The curved cornetto I made a decade ago was particularly challenging to keep the two bores edges parallel, and the two halves were fond of twisting differently. That works out when you wrap it in leather, but I wonder about the larger and stiffer parts of a dulcian, the internal wall seperating the ascending and descending bores of a dulcian is at issue here, failure to make and keep the glue joint there is fatal; and the width of that wall i perhaps 6-10mm near the turn.

One can make tools for the undercutting - rifflers, float-rifflers, curved-blade knives; the narrow bore and small toneholes of crumhorns are hard to undercut, but most other instruments are sufficiently accessible; it was done historically...

Splitting the body was never a common practice for Recorders, and if one considers how many of the instruments in this collection alone strongly resemble bananas (which movement is highly stressful on the glue joint in question), the fact they didnt have epoxy in the 16c, and the difficulty of leather-wrapping thru a fontanelle-protected key; I can understand why so few if any) recorders were done split.

Dana ,

I have an interesting 'recorder' from South America dating as early as the 17th century that is split bore. It is in the long style of the Anasazi tube flutes. Yes, the bore is open at the fipple and was corrected at a later time with a piece of coper wire.

Thomas, the pocketing referred to is often where no hole is.

Steven, I have private email from Adrian Brown, yes he used strain gauge calipers to take his measurements. Blocks were not removed in respect of the risks that involves, making it difficult to measure windway details. Gotta get (make?) me a strain gauge caliper.