[pontius]

They are not intentionally concave. They are left concave because they still play well enough with a concave table. They are concave because the facings are milled and done quickly. They are "allowed" to be convex because this gives the cut off material some place to go. So its not a goal, its an exception. I prefer not to make that exception.

If it's because of poor QC (milled quickly), wouldn't at least 50% of the non-flat tables be convex rather than concave? I always see concave rather than convex on original pieces. Or are you suggestion the convex ones go in the re-grind machine?

 

[turf3]

In the milling process, the surface heats and expands due to the heat from the cutting operation. Once it returns to room temp, the outer layer shrinks more, leaving a concave surface.

 

[pontius]

In the milling process, the surface heats and expands due to the heat from the cutting operation. Once it returns to room temp, the outer layer shrinks more, leaving a concave surface.

I'm confused. Wouldn't that leave it convex?

edit: Ok I think I get what you are suggesting and that seems to maybe make sense. This is the first plausible scenario I can imagine for concave tables that were not intentionally ground that way.

If you have a dead flat grinding surface, how else can you get concave results? Convex results can easily happen if there peice is not kept perfectly secured and not able to move or wobble during the process.

 

[stevesklar]

I believe this is one of the machined tables methods that would create concave tables (there's different machining methods, plus more manual methods).
I have it and others I'm putting together on various past methods of mouthpiece manufacturing.
You have to keep in mind the wear of the abrasive wheel and any potential heat even though it is liquid cooled.

 

[skeller047]

Regarding the OP's piece, he mentions that the concavity extends into the window area. This is common on Link HR pieces I've bought. If the concavity stops BELOW the window, then it can be OK as long as the ligature is up near the top of the table. But lower down and the reed can be pulled away from the facing, which will cause a leak at the base of the window.

Kirill's photos show that the reed would seal properly on those pieces, assuming there was a complete flat area at the base of the window. And as he says, the standard warp of a reed, where the center is higher than the edges, would be accommodated by this kind of concave table.

Having said that, I'm with Phil - I prefer a flat table. When I modified a few Link soprano pieces a couple years ago, the first thing I did was flatten the table, and recut the curve. Two of them had concavities that leaked into the base of the window, this makes them more resistant feeling, and wonky if the reed is the least bit warped. They all play very nice now.

 

[Dr G]

If it's because of poor QC (milled quickly), wouldn't at least 50% of the non-flat tables be convex rather than concave?

That would presume that the defect is due to random cause.

I always see concave rather than convex on original pieces. Or are you suggestion the convex ones go in the re-grind machine?

Others have detailed defects due to expansion from overheating - certainly possible. The contrary case can occur when the cut is too large and compresses the base material as it cuts. Once the cut is finished, and the force removed, elastic recovery will cause the material to spring back. A thicker section will have more elastic recovery than a thin one, thus cutting into a cylindrical cross-section will a non-uniform surface. These are not necessarily exclusive - one can have both overheating and excessive force. That's why an experienced machinist will be sure that the last passes are well-cooled and take thinner cuts.

 

[Ixthusdan]

Out of curiosity, I checked out my mouth pieces: Link STMNY metal, 1998, Vandoren Java Jumbo, hr, 2001, and Cannonball (Meyer clone), hr, 2019. Obviously the Link and the Cannonball are produced by Babbitt. The Link was flat, both directions. The Vandoren was concave, both directions. The Cannonball is flat across the table but concave the long way, flat before the window. I would have never looked had I not seen this thread. I don't like the Vandoren because I stopped caring for a high baffle. I toss between the Link and the Cannonball. Frequently I must peel the reed off of the table of the Cannonball, it seals quite well with no signs of moisture in the table. Could this be much ado about nothing? Perhaps it is affecting me and I do not know it?

 

[mmichel]

Out of curiosity, I checked out my mouth pieces: Link STMNY metal, 1998, Vandoren Java Jumbo, hr, 2001, and Cannonball (Meyer clone), hr, 2019. Obviously the Link and the Cannonball are produced by Babbitt. The Link was flat, both directions. The Vandoren was concave, both directions. The Cannonball is flat across the table but concave the long way, flat before the window. I would have never looked had I not seen this thread. I don't like the Vandoren because I stopped caring for a high baffle. I toss between the Link and the Cannonball. Frequently I must peel the reed off of the table of the Cannonball, it seals quite well with no signs of moisture in the table. Could this be much ado about nothing? Perhaps it is affecting me and I do not know it?

Every stock Babbitt piece I've ever used and measured has had a concavity (in both directions) in the table. The issue with a longitudinal concavity, as others have pointed out, isn't necessarily that it doesn't seal, but that the response of the reed (and whether or not it seals) can vary quite a bit depending on where you place the ligature and how firmly you tighten it.

I personally prefer flat facings because they seem to be more reed friendly and to have fewer issues with reed chirps and squeaking. I also flatten my reed tables before every playing session, so YMMV.

 

[Ixthusdan]

I use a Reed Geek to flatten my reed tables, and get best results if I work them every time. I was surprised at the Vandoren. No one complains about them.

 

[Dr G]

Out of curiosity, I checked out my mouth pieces: Link STMNY metal, 1998, Vandoren Java Jumbo, hr, 2001, and Cannonball (Meyer clone), hr, 2019. Obviously the Link and the Cannonball are produced by Babbitt. The Link was flat, both directions. The Vandoren was concave, both directions. The Cannonball is flat across the table but concave the long way, flat before the window. I would have never looked had I not seen this thread. I don't like the Vandoren because I stopped caring for a high baffle. I toss between the Link and the Cannonball. Frequently I must peel the reed off of the table of the Cannonball, it seals quite well with no signs of moisture in the table. Could this be much ado about nothing? Perhaps it is affecting me and I do not know it?

"Much ado about nothing?" If the table is bad, then you may have issues. If the table is good, you may still have issues, but not due to the table.

Feeling lucky?

 

[JonasH]

Im sure this is intentional. The lig presses at a small area only but the reed needs to seal at the break where there is no lig. Concavity places the pressure where it is needed - closer to the break.

 

[1saxman]

Jon Van Wie brought concavity to the general notice years ago as he preferred to do that with his refacings. He did it on a Guardala of mine and while there was an elliptical low area inside the boundaries of the table, the edges were 'flat', so you would not see the concavity with the mouthpiece on a reference flat surface. The OP's mouthpiece reflects a 'dished' table in the longitudinal direction which shows light on a flat surface. I do not think this is a good attribute and he should have the mouthpiece re-faced which probably will result in an epiphany for him.

 

[lostcircuits]

Isn't that more a philosophical question? You have the flat tablers and the knights of the round table. But the holy grail has never been found, otherwise we wouldn't be trying to turn imperfections into mantras.

With cooling blocks we made slightly convex surfaces because somebody claimed it would allow for better spreading of the thermal interface material and the pressure would then actually flatten the block anyway (hint: marketing parlance). But it's so easy to turn incompetence and cutting corners into features nowadays by making up bogus arguments with pseudo-logical statements.

If you have two flat surfaces, they will match each other and provide good adherence and seal. If you have any contours, then it becomes random whether thy match and if one material is less rigid or weaker, it will eventually conform to the stronger one.

But do you really want to artificially bend a reed? I guess, a lot of players do it anyway by biting/clamping too hard. And if you bend a reed against its long axis, will it still vibrate?

I guess, some like that effect, I don't

 

[Dr G]

Isn't that more a philosophical question? You have the flat tablers and the knights of the round table. But the holy grail has never been found, otherwise we wouldn't be trying to turn imperfections into mantras.

Flat tablers, defected table... The third case is that of the intentionally concave table.

I like a mouthpiece that plays well - some of them have had concave tables, but it really didn't make a difference to me as long as it didn't create a problem.

 

[EZ]

If the table is causing a problem, just get rid of it!

 

[skeller047]

We have to think about what we want the reed to do. We want it to bend against facing and spring back, several hundred times per second, up to 1000+ times per second. And completely seal against the mouthpiece below the facing curve. That’s what makes the noise we like.

Should we glue it to the table? That would work, until we want to change it. Barring that, a good ligature and a flat table seems like the best option, to me anyway.

I know what the proponents of a concave table say, and indeed, as long as the reed is supported along it’s length, and seals at the base of the window, it should work OK. A depression in the table center, or the concave section down the center that Kirill Poudavoff showed earlier, would meet that requirement. These allow for reed swelling (somewhat) and don’t interfere with ligature placement, so should be fine.

However, the OP’s photos show a piece that won’t let you put the ligature down low. Doing that would raise the reed away from the base of the window, destroying the seal and making the instrument hard to play. That mouthpiece needs fixing, IMHO.

As for me, I like flat tables.

 

[Wonko]

I am no expert, but here's my experience.
I had been wondering about this because I had read all sorts of stuf on this (and the other) forum about the need for a perfectly flat table. Some people also said that hand finished mouthpieces are far superior to machine made ones.....
Last summer I decided to try out if a hand finished mouthpiece would play better than my OttoLink (tone edge) that I have been playing for the last 3 years.
So I ordered a PPT mouthpiece for my tenor. It's quite a different beast than the Otto Link, I am still getting used to it.
It brought to light that my embouchure needed some adjustments, so that means I am becoming a better player because of this mouthpiece (I hope).
And I must say that it seems a bit easier to play than my Otto Link. Most noticable: I can play ppp better than I used to.In a month or 2 I will contact the guy that my tech recomended for refacing and have my Meyer baritone mouthpiece refaced to see if that will play better after refacing.
So, in short, I think that I am moving to the flat-table bunch... ;-)

 

[stevesklar]

I can't recall who it was, but there was one or a couple custom mouthpiece makers who would put a horizontal small concave section. Thus one knew where to place the ligature, and to know not to get a lig that put a singular horizontal "plate".

I have an earlier video (somewhere, hopefully .. i think 1998ish) that showed a more crude method of cutting the table and rails. It was less swoops back and forth, which would have more pressure and heat to the scenario.

 

[KPoudavoff]

So, in short, I think that I am moving to the flat-table bunch... ;-)

Thinking that your performance improved due to a flat table is very illogical.

There are four things that contribute to a well playing mouthpiece (IMO):

• good design
• well cut table
• well cut facing
• well finished baffle, tip and etc.

First of all, you are talking about two completely different mouthpiece designs, right?
Secondly, off the factory, Otto links come with all sorts of issues (crooked facings, horrible finishing work and all sorts of table issues) that can contribute to the performance problems that you mentioned. Off the factory, they will never compete with a refaced or a boutique-made mouthpiece.

So, in my opinion, if a mouthpiece lacks at least one of the four qualities above, it will not play well.

 

[Sigmund451]

IMO a flat table is an excellent foundation to base the rest of the variables upon. I also prefer a sound foundation for my house.