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Does Pipemetal Have A "grain"


Nick Bennett
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A discussion (on another thread) about the thermal expansion of pipes has led me to wonder whether pipemetal has the same physical properties in both directions.

 

Do pipes have to be made the same way round in the metal, or can some be made along the length of the sheet and some across it, if you see what I mean.

 

If somebody were to cut a piece out of a sheet of pipemetal and leave it on the bench, would anyone entering the room and picking it up be able to tell which way round it was on the bench when it was cast?

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A discussion (on another thread) about the thermal expansion of pipes has led me to wonder whether pipemetal has the same physical properties in both directions.

 

Do pipes have to be made the same way round in the metal, or can some be made along the length of the sheet and some across it, if you see what I mean.

 

If somebody were to cut a piece out of a sheet of pipemetal and leave it on the bench, would anyone entering the room and picking it up be able to tell which way round it was on the bench when it was cast?

 

 

=======================

 

 

I would have to check this out with my metalurgist brother, but I seem to recall,

( from about 40 years ago) that we discussed this as youngsters.

 

So far as I know, the structure of both plain and spotted pipe-metal is granular, and therefore uniform in the lateral and longitudinal planes.

 

Now, pure tin may be a little different, because I believe it is cold-rolled, which may have the effect of lining up the crystal structure of the metal end-to-end. The same may also be true of copper sheet.

 

I don't quite know how zinc fits into the equation, because zinc is cast and then rolled during the sheet-making process.

 

Anyway, I'll ask ma "bro" and see what he comes up with. I suppose that if he inspects the Russian gas pipeline across Siberia, a miserable organ-pipe is not going to present much of a challenge!

 

MM

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A discussion (on another thread) about the thermal expansion of pipes has led me to wonder whether pipemetal has the same physical properties in both directions.

 

Do pipes have to be made the same way round in the metal, or can some be made along the length of the sheet and some across it, if you see what I mean.

 

If somebody were to cut a piece out of a sheet of pipemetal and leave it on the bench, would anyone entering the room and picking it up be able to tell which way round it was on the bench when it was cast?

 

I remember seeing the process at the R&D factory a few years ago, where molten metal was poured onto a flat stone surface. From this, you would expect that the metal structure was the same in both dimensions. However, I can't remember what the process was after the metal had cooled - whether or not there was some rolling or pressing involved.

 

JJK

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Guest Barry Oakley

 

I remember seeing the process at the R&D factory a few years ago, where molten metal was poured onto a flat stone surface. From this, you would expect that the metal structure was the same in both dimensions. However, I can't remember what the process was after the metal had cooled - whether or not there was some rolling or pressing involved.

 

JJK

 

Once the metal is cast into sheets there is no rolling. Pieces are cut from the sheet and formed into shapes necessary to construct a pipe using a mandrel. However, prior to this the metal is often planed to taper its thickness towards the top of the pipe. Where the edges meet a vee is cut to allow solder to flow into the join. Hope this perhaps rekindles your memory.

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Once the metal is cast into sheets there is no rolling. Pieces are cut from the sheet and formed into shapes necessary to construct a pipe using a mandrel. However, prior to this the metal is often planed to taper its thickness towards the top of the pipe. Where the edges meet a vee is cut to allow solder to flow into the join. Hope this perhaps rekindles your memory.

 

 

=====================

 

Correction here.......

 

Zinc sheet is cold-rolled at the production phase as a matter of course.

 

The best lead for pipes is hammered lead, which increases the density of the material.

 

Copper is cast as an ingot in a crucible, and then hot-rolled into sheet: similarly with brass sheet.

 

MM

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Once the metal is cast into sheets there is no rolling. Pieces are cut from the sheet and formed into shapes necessary to construct a pipe using a mandrel. However, prior to this the metal is often planed to taper its thickness towards the top of the pipe. Where the edges meet a vee is cut to allow solder to flow into the join. Hope this perhaps rekindles your memory.

 

Many years ago I had to show a management group round our metal shop who came from the Steel Company of Wales and wanted to see how organ builders cast their pipe metal.

 

As they watched a casting being done they fell about laughing, mentioning the Fred Flintstone approach. When they had calmed down I pointed out we were not rolling metal to get the required thickness but casting it to any thickness we wanted and if they could come up with a better, more cost efficient system for what we needed I would like to know it. They thought hard and long but had no answer. They were decent enough to apologise for their earlier comments though.

 

FF

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Many years ago I had to show a management group round our metal shop who came from the Steel Company of Wales and wanted to see how organ builders cast their pipe metal.

 

As they watched a casting being done they fell about laughing, mentioning the Fred Flintstone approach. When they had calmed down I pointed out we were not rolling metal to get the required thickness but casting it to any thickness we wanted and if they could come up with a better, more cost efficient system for what we needed I would like to know it. They thought hard and long but had no answer. They were decent enough to apologise for their earlier comments though.

 

FF

 

 

============================

 

Ah! The wisdom of the traditional craftsman!

 

Here's a pithy short-story which illustrates the point.

 

My brother went to a Sheffield Steel works, and with a heat-protective suits and dark visors, he and a steel-worker climbed the stairs to observe the molten metal in the huge vat; prior to it being poured.

 

My brother had a spectrometer in hand, and he used this to assess the heat and chemical content of the mix.

 

"I think it's a little cool yet," my brother suggested.

 

The steel-worker spat onto the molten metal. The spittel sizzled and zig-zagged across the surface, and the worker said, "Nay! That's spot on lad! I can tell by the speed my spit moves and then evaporates."

 

My brother checked his equipment, and realised that he failed to calibrate it correctly.

 

He tried again, and the steel-worker was accurate to within half a degree!!

 

:rolleyes:

 

MM

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A discussion (on another thread) about the thermal expansion of pipes has led me to wonder whether pipemetal has the same physical properties in both directions.

 

Do pipes have to be made the same way round in the metal, or can some be made along the length of the sheet and some across it, if you see what I mean.

 

If somebody were to cut a piece out of a sheet of pipemetal and leave it on the bench, would anyone entering the room and picking it up be able to tell which way round it was on the bench when it was cast?

 

==================

 

 

It seems that metals are granular in structure, but not in any sense "grained" as with wood.

 

Wood, being fibrous in structure, is built around long-chain bio-chemical molecules, and it is the interlocking nature of these fibres which give wood its extrordinary strength in relation to weight.

 

More importantly, wood retains considerable strength even when partly broken, as anyone who has tried to break a small branch of greenwood with the bare-hands will know.

 

The structure of metals is therefore both granular and crystalline; the strength of which is determined by the metallic atomic-bond, which can be "worked" in various ways to our advantage or alloyed into specialist materials, of which pipe-organ metal is but one.

 

So to answer the question, metal and metal-alloys do not have a grain as wood does.......so far!

 

However, my brother has done extensive work on metal "powder technology,"

where metals are mixed as powder and then sintered into a solid material.

 

Recognising that the limitation of metals was the basic atomic-bond, (which includes any improvements to that bond which may result from various methods of working, alloying and carbonising), he set out to induce molecular "grain" in metal; thus imitating the inherent strength of wood.

 

I think the idea was to create a steel twice as strong, but half the weight.

 

I don't know how far he got with this, but it caused a bit of a stir among the "metal-heads".

 

I think the problem, as always, was finding the funding to carry out some fairly radical research and testing, but in theory, it should be possible.

 

Unfortunately, he is away at the moment, so I haven't been able to ask him about anything.

 

He's possibly galavanting across the Russian Steppes on horseback, or something equally ridiculous, which is probably a lot safer than being handed a bottle of "extreme" vodka and pushed gleefully onto a white water raft with a group of drunken, masochistic Slovakians with a death-wish!!

 

I always thought it was musicians who had the fun....not the scientists.

 

:unsure::D:D

 

MM

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