[puredream]

I check out a video showed how selmer formed their saxophone neck. I am curious about what the liqour is they put in the straight cone to avoid wall collapse while forming. It looks like some soft ice. Does anyone knows?

 

[milandro]

Selmer says it’s ice, they don’t say whether it is just water cooled down to icy temperature or if it has anything added. If it had anything added its freezing point will probably be lower than 0°C.

What do you mean by soft?

 

[Tzadik]

Water expands below 0° C (below 32° F).
When you warming up the neck to remove the ice... some internal stresses remain into the sheet of brass of the neck... due to the contracion.
They can help to make the neck "stiffer"... or not.

Another point is ice is very hard and fragile... to bent.
If the ice cracks (inside the tube), it can break the sheet of metal.


I know it's generally used lead (inside the tube... before forming the neck) because it's soft... and it can easily bent, with no crackings of any kind.
It will be interesting to know why the choice of the water.

 

[puredream]

soft ice means it was crowded out as sand. If it's pure ice, they would keep the necks in the refrigerator rather than in some unknown liquor with room temperature. My friend ever try to fill in the water and keep the neck in the refrigerator. The neck had been annealed before freezing, but the wall still collapse or break while it was formed.

 

[milandro]

well, the liquid around the necks could be coolant such as Ethylene glycol (which freezes at way less than 0°c!) all kept in a tank with refrigerating elements and the liquid inside the necks something else . if one does this all the time would also know to fill the neck with enough liquid that it’s expansion wouldn’t crack the neck

Most necks, surely those made in Taiwan, are made by hydroforming.

http://www.americanhydroformers.com/what-is-hydroforming.aspx


Cerrobend is another, non liquid material often used to bend tubes

 

[zenkibou]

As described here under "Bending Brass", it look likes it's a frozen solution made of water+soap.
They are talking about "Wood's metal" as well, which is solid at room temperature but liquid at 70°C (where water is solid at <0°C and liquid at room temp).
Water and soap look cheaper but I guess it depends of how long it takes to bend it !

 

[milandro]

cerrobend is wood’s metal

http://en.wikipedia.org/wiki/Wood's_metal

it is not stuff that you would use without protections and most health and safety around the world would frown upon its use

“.........Wood's metal is toxic because it contains lead and cadmium, and therefore contact with the bare skin is thought to be harmful, especially in the molten state. Vapour from cadmium-containing alloys is also known to pose a danger to humans. Cadmium poisoning carries the risk of cancer, anosmia (loss of sense of smell), and damage to the liver, kidneys, nerves, bones, and respiratory system. Field's metal is a non-toxic alternative.

The dust may form flammable mixtures with air........”

Perhaps better Field’s metal...............:bluewink2:


http://en.wikipedia.org/wiki/Field's_metal

 

[tictactux]

http://en.wikipedia.org/wiki/Polycaprolactone

 

[milandro]

peut-être

 

[puredream]

http://en.wikipedia.org/wiki/Polycaprolactone

Does anyone evey use this to bend metal? However, I think this is very closer to the answer.

I think it's less possible the liquor is ice-like material, because the surface of bending mold is neither frosting nor wetting.

 

[griff136]

Does anyone evey use this to bend metal? However, I think this is very closer to the answer.

I think it's less possible the liquor is ice-like material, because the surface of bending mold is neither frosting nor wetting.

I use a variant called Polymorph for other applications in the workshop.

It becomes very firm when cooled and like gel when heated - I doubt if this is used when bending/forming tubes as in its hardened state it would be difficult to bend without the use of say hydraulic pressure. It also cools very quickly and would be of no use in its molten state.

I use cerrobend for tubing.

 

[saxpiece]

A water foaming mixture, whatever that is.

Once welded, the tubes are plugged at one end, filled with a water foaming mixture and plunged into an alcohol bath.
Ice formed in the cone maintains the structural integrity while it is bent.

http://www.selmer.fr/fabliste.php?page=saxophone

It's also good just to listen to the background soundtrack at the Selmer site btw.

 

[milandro]

i seriously doubt that the bath the necks are in is anything else than water, can’t be a flammable liquid like alcohol

 

[Bottle Opener]

I heard they no longer use liquor. Apparently the workers kept taking sips and using up the supply too quickly.

 

[milandro]

this is another video

 

[saxpiece]

"Once welded, the tubes are plugged at one end, filled with a water foaming mixture and plunged into an alcohol bath.
Ice formed in the cone maintains the structural integrity while it is bent."

---------------------------------------------------------------------------------------

Here is my guess, by trying to match the above statement to the above video.

In the above video, the worker seems to plug the cork end of the neck tube by putting something in the neck tube and ramming it down the neck tube and then I would presume that the neck tube is filled with the water foaming mixture.

The water foaming mixture is probably a detergent/water mix which freezes in a different way to just water and the frozen detergent/water mix maintains structural integrity as the neck tube is bent and also probably makes bending easier, rather than just water ice which would probably have a tendency to break into larger pieces as the neck tube was bent and also be harder to bend, therefore losing some of it's structural integrity as the neck tube was bent.

The alcohol bath (a neck tube bath can be seen in the above video) probably freezes the water foaming mixture and might be something like an ethanol bath or whatever type of alcohol bath that can freeze water.

 

[milandro]

if that were alcohol, alone, the fumes could ignite with a simple spark, which in the presence of electricity is not impossible but almost certain. My guess is that a little alcohol is added to normal water (glycol would work as well) to keep it liquid while having a temperature lower than the freezing point than whatever is in the pipe.

This way the solution would not ignite.

 

[saxpiece]

The old frozen detergent/water mix trick for bending brass tubes is an old one that has been used by many instrument makers and others.

http://www.shopfloortalk.com/forums/archive/index.php?t-36470.html

 

[milandro]

yes here the original posts

http://www.garagejournal.com/forum/showthread.php?t=15528

 

[Aldevis]

As described here under "Bending Brass", it look likes it's a frozen solution made of water+soap.

Water and soap is what I heard. Expanding ice just overflows. Apparently Bach trumpets started first using cooling liquids rather than lead or tar (I hope the translation is appropriate).
Tar might still be used by some french horn maker.