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Up Topic Welding Industry / Technical Discussions / The T-joint boogie and why it happens..
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- - By Kix (****) Date 10-25-2007 12:43
I know all of you are familiar with this common occurrence that happens when working with stainless and the GTAW process.  Sometimes when welding say a T-joint on the table you'll be running a long and all of the sudden your part starts hopping around all over the place and you have to reach out with a finger and hold it down.  Sometimes when you stop the hop with your finger it will stay stopped and sometimes it won't.  My question is whats going on that causes this phenomenon?  I promise I won't ask anymore-technical questions for a little while to give you all a break after this one. ;-)   I just got back from Blackwater U.S.A last night after being gone for a few days so I have a lot of reading to catch up on.

Thanks, Ray C.
Parent - - By Lawrence (*****) Date 10-25-2007 12:58
Ray,

Thats a good quesiton.  And boy have I had that experience.

I know it has to do with the L'ectricity flowing from the work to the table and a less than adequate connection. But I would also like to hear a more technical explaination.

I also know that if the connection is very bad that little arc strikes will occur on the bottom of the work which can be a cause of untempered martensite in some alloys.

For fine tig work on small pieces we do one of two things.... 

A small pinch clamp or a good sized aligator clamp with a lightweight braided cable that is attached to the table is a good thing to clip to your work if the work clamp is too heafty to attach directly to the work itself.

Secondly, a nice piece of heavy scrap (2x3x1") with a little piece of 3/8 round stock 10" with a 90 degree bend at the last 3 inches... The end of the roundstock can be laid atop the work will hold it down and control the boogie.
Parent - - By CWI555 (*****) Date 10-25-2007 16:35
Lawrence

"arc strikes will occur on the bottom of the work which can be a cause of untempered martensite in some alloys." I've heard this one before, and seen it, but cannot seem to find documentation on it. Do you happen to know a reliable book or source for this information?
Parent - - By Lawrence (*****) Date 10-25-2007 16:58
Gerald,

I have some in house training materials from UAL stacked away someplace... We had surface temper etch procedures after machining or welding on  High Strength steel... There was some basic metellurgical data and if I can dig it up I'll try to get a PDF for ya.

Here is a link to a forum poste along the same lines and a couple of good links in the postings with data.

http://www.aws.org/cgi-bin/mwf/topic_show.pl?tid=8695
Parent - By CWI555 (*****) Date 10-25-2007 18:02
thanks, It would be good to get some definitive documentation on the matter.
Parent - - By aevald (*****) Date 10-25-2007 13:24
Hello Ray, as Lawrence has stated, I feel that it generally happens when the part being welded is on slightly unstable ground(pardon the pun). As was also stated, it is an electrical phenomenon, but I feel it is related to the magnetic flux that is set-up in the part as it is being welded. I also feel there is a harmonic vibration portion to this, similar to the sort of thing that occurs in acoustic speakers when they resonate at certain frequencies. I too might like to hear from some of the more "physics" minded individuals on the forum here. Great question, I'm sure this one should invite some lively conversations. Best regards, Allan
Parent - - By Tommyjoking (****) Date 10-25-2007 14:11 Edited 10-25-2007 14:14
hmmmm  I have experienced this phenomena on parts well over two pounds (always some sort of steel) but yea they do that boogie.   I have always thought this was due to heat input and some kind of kinetic distortion phenomena happening.  A quick lock down in the vice cures this.

I have noticed with tig in particular that laying upon the table does not nesseceraly mean a good ground. The Third Finger which I believe is what Lawrence is describing is an invauable tool to the tig welder.  A long piece of roundstock bent at 90 at one end and sharpened...the remander a long length with a crosspiece/bar welded to it so the 90 end will always point downwards with max weight and pressure.  These devices prevent the boogie and also help prevent inadvertent arc strikes from the part trying to get a solid grounding. Strange how this always in my experience applies only to steel (carbon, ss, what have you).   Yep you bet i am phising for some of those gurus to provide scientific explanation for this one.  this is a good post comon you guys
Parent - - By Lawrence (*****) Date 10-25-2007 15:13
"The third finger"    Tommy has named the thing...!   never knew that.

I've experienced the "Boogie" on stainless, the whole family of inconels, PH super alloys, Titanium, Waspalloy, (You would think I would learn my lesson and take precautions every time an arc was struck)

I'm with Allan on some sort of "Harmonic"  Although I don't quite know how it occurs with DCEN that is moving in one direction.

Bring it on Al and Stephen!
Parent - - By aevald (*****) Date 10-25-2007 15:36
Hello Lawrence, here is another hypothetical on the subject. Even though it is DCEN current(so it isn't a case of switching back and forth between DCEN and DCEP that would be causing a harmonic), it may be the inconsistent grounding issue that is causing the magnetic field generated by the current to set-up and collapse at a specific frequency and then cause the resonation or vibration. Although the actual material being welded may not be magnetic, the current flowing through it during the welding process will set up magnetic flux patterns or fields that can influence motion. Just another thought. Regards, Allan
Parent - - By CWI555 (*****) Date 10-25-2007 17:42 Edited 10-25-2007 17:46
In regards to hopping and third fingers:

If you have physical movement, there is energy manifesting itself. I've never heard of a case in which it was reported on plain carbon and some not so plain carbons.
Usually it's inconel, stainless, etc. For the theory of magnetism, the Titanium element that is also witnessed would seem to throw that theory out, as Ti is not ferromagnetic. (I believe it is diamagnetic). For that material, the amount of current necessary to set up a magnetic field would be phenomenal and highly unlikely.

If it was not for seeing it in ti it would be easy to attribute it to magnetism, as the other materials mentioned contain nickel which is ferromagnetic. However, Iron is ferromagnetic , so what common thread do the materials experiencing this hopping phenomenon have? (ferromagnetic, diamagnetic, and paramagnetic materials)
None I've ever heard of are carbon, the ones that have been reported are all higher end alloys consisting of nickel, titanium, moly, chromium, and a host of others. The exception to these materials is in carbon content, and iron content.

For that reason, I'll add my pet hypothesis to the fray.

EMAT stands for electromagnetic acoustic transmission. It is a UT method that sets up partical vibration via electromagnetic eddy currents.
http://www.ndt.net/ndtaz/content.php?id=144
It is also well known to the UT types that current can set up this vibration, it is also known that heating can do the same thing. (Localized induction of ultrasonic and infrasonic vibrations via localized laser heating have been documented and are under R&D in many places for use in NDE)
Resonance http://www.ndt.net/ndtaz/content.php?id=284
http://www.kettering.edu/~drussell/demos.html

It's my opinion, it's a resonance harmonics in either the infrasonic, or subsonic range that sets up these mechanical vibrations.
The carbon and iron content of standard carbons may just not be capable of generating this harmonic resonance due to their natural frequency as modified by their grain structure and size.

My two cents worth,
Gerald
Parent - - By aevald (*****) Date 10-25-2007 18:29
Hello Gerald, I read your post and do see where you are coming from regarding the magnetics, however let me interject this thought. When someone is using an air-carbon arc and you watch the leads from the machine to this tool you will notice substantial movement of the leads whenever the gouging is taking place. The leads in this case are made up of copper, rubber, and possibly some other insulating materials, none of these components are magnetic. My thoughts are still along the lines that there are fields surrounding the lead and possibly even the individual strands of the cable itself. As the levels of current fluctuate while in use these fields become stronger and weaker and possibly even react to the natural magnetic field of the earth itself. I know this line of reasoning is out there, but I can't but help to think this could be a part of the effect of what is happening. Also consider a compass with it's needle that points north, it is reacting to the earth's magnetic poles, why wouldn't a similar occurance be possible in this case. Even though some of the materials that are being discussed here are definitely not magnetic themselves, the current that is flowing through them does set up a type of magnetic flux or field by it's presence. In fact the ferromagnetic materials may have a cancelling effect on this phenomenon and may explain why this occurs with the non-magnetic materials instead of the others. Just a few more thoughts for consideration. Regards, Allan
Parent - By Kix (****) Date 10-25-2007 18:40
Yeah i've seen this with the leads with someone who was useing spray arc GMAW.  Eerytime he pulled the trigger you could watch all the grinding dust stand up and the cables moved a bit too if you watched close enough.  Very interesting theory!
Parent - - By CWI555 (*****) Date 10-25-2007 20:41 Edited 10-31-2007 16:01
I've thought about what you have stated, but I would have to stick to the non magnetic cause. The leads from carbon arc are as you say, but those cables are routinely used for coil shot MT. I can make a ferromagnetic material hop around by laying it just so in a coil, but the energies typically associated with the welding processes mentioned don't usually get to that level, and it doesn't explain why non ferromagnetic materials react the same as para and diamagentic materials with no other commonality readily visible.

Again, it's the lack of reaction under those conditions by a ferromagnetic material (iron), and the presence of a ferromagnetic material (nickel), that lead me to the hypothesis as stated. You will not see the same reaction from both. Then you also see the reaction from paramagnetic, and diamagnetic materials.

Diamagnetic metals have a very weak and negative susceptibility to magnetic fields. Diamagnetic materials are slightly repelled by a magnetic field and the material does not retain the magnetic properties when the external field is removed. (copper, silver, gold etc.)

Paramagnetic metals have a small and positive susceptibility to magnetic fields. These materials are slightly attracted by a magnetic field and the material does not retain the magnetic properties when the external field is removed.(manganese, moly, and after the research Titanium etc.)

Ferromagnetic materials have a large and positive susceptibility to an external magnetic field. They exhibit a strong attraction to magnetic fields and are able to retain their magnetic properties after the external field has been removed. (nickel, iron, cobalt etc.)

The one absent state of this is the carbon and iron. materials that are primarily made of them don't have this same reaction.

Maybe I am off base here, but something other than magnetism, to me, is the only logical explanation when you run down the variables in a process of elimination.
Parent - - By mooseye (**) Date 10-26-2007 00:29
There is one commonality. They are all electricaly conductive.
I have witnessed(yesterday again) objects that get the correct bump on the right surface set up a vibration that allow the object(in yesterdays case my stanley thermos bottle) to seem to move under their own power.
Due to this observation my theroy is that the flat surface of the part and the table experience a ground loss arc between them which sets up this vibration which is perpetuated by further arcing. I don't know what it is called but it behaves like an air float.
This seems to me to help explain the lesser occourance with carbon or mild steel since typicaly the surface is less on plane and also seems to aquire a ground much more consistantly and solidly.
Any bites. Or bights, or bytes?
Parent - - By CWI555 (*****) Date 10-26-2007 00:38
I agree that the electrical conductivity plays a role. But I've seen pieces move about without any sign of arc flashing/strike.
Parent - By mooseye (**) Date 10-26-2007 00:49
Key word = theory!   Ha ha I know, there was no arc under my coffee jug either. I was just thinking maybe it only take the one little one or one of the other forces that have been brought up to set up the vibration.
Who knows? It is an interesting subject!
Parent - - By darren (***) Date 10-28-2007 20:57
quartz compresses when a current is passed through it, or if it is squeezed it releases a current. maybe cables shrink lengthwise when a current is passed though them.
Parent - By CWI555 (*****) Date 10-29-2007 04:08
Yes it's called a peizoelectric material. I don't know what values copper has though.
Parent - - By DaveBoyer (*****) Date 10-30-2007 05:28
I am pretty sure You will find that the cables are reacting to the magnetic field, not changing length due to Peizoelctric effect.
Parent - - By darren (***) Date 10-30-2007 09:28
does copper react to magnetic field? gerald had some definitions that might help. from the looks of the way they react it reminds me of a hose under  internal air compression which is shortening a little due to it expanding radially and taking up a little slack. probably optical illusion though.
Parent - - By CWI555 (*****) Date 10-31-2007 03:36
http://orca.phys.uvic.ca/~tatum/elmag/em15.pdf
I would draw your attention to equation III paragraph 15.5 on the attached link.
And then the last illustration on the following link.
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magfor.html#c2 

Copper being diamagnetic, It doesn't retain a magnetic field. But I believe the above information gives some credence to your idea darren.

Regards,
Gerald
Parent - - By DaveBoyer (*****) Date 10-31-2007 04:13 Edited 10-31-2007 04:23
I do know that copper and aluminum both react to magnetic fields due to "eddy currents" The case of the spedometer and the magnetic dampening of a compas card put this to use. I suspect but don't have any proof that this same or a similar mechanism is involved in why the cables jump. If copper was a peizoelectric material You could get power out of it by squeezing it, and I don't know that that happens.
Parent - By Tommyjoking (****) Date 10-31-2007 07:58
"does copper react to magnetic field?"    of course thats how induction in a generator occurs....does it physically react? Yes when strong currents are in place
Parent - - By hogan (****) Date 10-26-2007 18:45
it may be the inconsistent grounding issue that is causing the magnetic field generated by the current to set-up and collapse at a specific frequency

i think this would have an obvious and detrimental effect on the arc. imo

etit: trying to respond to aevald two posts up
Parent - - By Kix (****) Date 10-31-2007 12:32
When the boogie is going down it has no effect on the arc.  Well, no effect with stainless anyway.
Parent - - By Tommyjoking (****) Date 11-01-2007 03:14
no effect on anything as far as I can see......Kix if you can lay the filler with it doing to boogie   I see no affect on weld quality......actually to me the vibration is so violent and quick that it has no effect on heat input really.    I just force my cup against it and keep on laying if neccesary.  If i can stop I  do and stop the boogie before continuing.
Parent - By Kix (****) Date 11-01-2007 12:48
I have no quality problems in the weld while it's shakin either and it has no effect on the arc.  If i stop and don't put something down on the piece that is being welded it will just keep on shakin.  If you try to hold it down with your cup and keep moving then you will push the piece along with you so you really just need to hold it down somehow.
Parent - By mooseye (**) Date 10-26-2007 00:58
I have a little fellow who does just that. We call him a ground man. hee hee haw haw.   But seriously, I will post a picture of him tommorow if I can find him.
Parent - - By Kix (****) Date 10-25-2007 14:22 Edited 10-25-2007 14:24
Ok, I'm smellin what you guys are cooking here.  What about this though on carbon steel if you had a bad connection while tig welding a t-joint all it would do is put little arc strikes on the bottom of the piece and you wouldn't get any hopping.  I've never had a carbon piece get to ah hoppin on me.  Maybe because the arc strikes weld it to the table a bit easier then stainless and therefor creating a better connection.  Also what if the arc strikes that you find on your stainless if you find any at all are from the hopping.  For instance while it's hopping it's constantly losing connection by just a little bit.
Parent - - By Lawrence (*****) Date 10-25-2007 15:17
Right Kix,

The thing about a small part ......um...tacking itself to the table?   Is that whilst it stops the boogie (by creating it's own good/better connection, it has caused a discontinuity that could be very bad news, depending on the alloy.
Parent - By Kix (****) Date 10-25-2007 16:04
Oh this is only on practice pieces like for training and stuff.  Just tacking 2 pieces of stainless together and running a practice fillet weld on it. If it's a production part it's getting a clamp and a ground put on it for sure!!! 
Parent - By mooseye (**) Date 10-26-2007 00:33
I just realized that I should have read the entire thread before posting. That is my theory in a acorn hull.
Parent - By mooseye (**) Date 10-26-2007 00:50
Not so easy to test since it is intermittent. A simple ground jumper would prevent ""boogie"ing", if this is correct, but how would you ever know?
Parent - - By medicinehawk01 (**) Date 10-25-2007 23:55
Ray, there is alot of good discussion and theories.......while I am certainly no genius I have yet to see a comment about the obvious: distortion. It seems to me that we tack up the peice to be welded and whether we use a jig , fixture or a square to make sure the part is straight, it is when we put heat on it while welding that the part we are welding becomes alive. I think that if the peice is clamped to a vice grip or vice with a good ground then we wouldn't be having this discussion, but even with a good grounded table top, with the part to be welded just stationary we will occasionally have this happen. Some times, I have caught myself grazing the cup of the torch on the work to get the whole gyro thing started, but then other times.....it just happens.
I work alot from a tripod with a chain vise so if I have alot of parts (tee joints) to weld, I usually chain up a piece of flat stock in the vice and clamp the part with a vice grip or finger grips and hardly ever have the problem, but I think distortion while welding is a major contributing factor as to why this happens.
Parent - - By CWI555 (*****) Date 10-26-2007 00:41
Heat is also a source of infrasonic vibrations. My opinion for what it's worth, your right about distortion, it would be inherent to lesser and greater degrees.
Parent - - By Tommyjoking (****) Date 10-26-2007 02:50
LOL!!  Third finger?  I don't know if thats the official name or not, but it works for me.

With regards to  Lawrence and  Geralds posts ....I misspoke when I said carbon steels...cause come to think of it, its always high alloys that seem to do it regularly.  4130 does it a lot, Inconels, ss etc.  That one idea of the types of metal that display it has the answer and the mystery.  I am enjoying reading the theories here immensely!   

The whole arc strike floating thing....hmmm  hard to see that as being it.  When I fail to to place a block or third finger (lol) on a very light part especially a polished one....a rash of arc strikes may be the result table side but no "boogie" to go with it.   And I agree with others comments that an inadvertent bump or touch can often set the "boogie" off.     A particular machined part I do on a regular basis will do it every single time on a certain weld joint if it is not somehow restrained.

Best regards
Tommy
Parent - By DaveBoyer (*****) Date 10-26-2007 04:23
No answers here, but a few points to ponder:
Even tho You are working with DC it is not totally smooth DC like You would get from a battery. There is still some fluctuations from the 60hz primary current.
Materials that don't stick to a magnet are still acted upon by a magnetic field, that is how an old fasioned car spedometer works. there is a magnet turning inside an aluminum cup, the cup tries to rotate too, but is working against a spring. The needle is atached to the cup.
With regards to arc strikes and untempered martinsite, this is the cause of the rivet yoke failures I have mentioned on several ocasions. I don't know where to direct anyone to find proper documentation of it, but plain & short, the arc heats a small portion of the material above critical, and the heated material is quenched by the surrounding mass of cold material. If the material is hardenable, there will me a hardened but not tempered area with a stress riser [the arc crater] just waiting to start a fracture.
Parent - - By CWI555 (*****) Date 10-26-2007 05:07
I wished I had a couple of days in your shop with a laser interferometric receiver. Coupling a transducer to the part would potentially dampen it, but using a laser, you could prove or disprove definitively the presence or lack of any form of sound vibration. I can say this, I've had the opportunity to perform acoustic field imaging with it, I believe it would work to qualify if there is any form of sound energy in the part. If you have a part that does it every time, it would be an ideal test sample.
Parent - - By CWI555 (*****) Date 10-26-2007 05:19
couple more thoughts,

There are some documents out there on the effects of resonant vibrations.
Thinking on the subject, it's also been stated that the "boogie" can be tipped off by inadvertently bumping the piece in question. That would imply the energy was already there but just under the threshold necessary to set off the dance.

That natural resonant frequency in piping systems has been known to cause ruptures of the system (sometimes dramatic ones) when an outside force or a surge in the line impinges on it.

If in fact it is a factor of resonance, recording of the event would show a walk up in frequency.

regards,
gerald
Parent - - By darren (***) Date 10-26-2007 09:51
same reason sometimes the pot wiggles on the electric stove. there is a resonant vibration set up from the 60hz input.
walls of Jericho and Gabriel's horn thing. or marching out of step when marching an army over a bridge.
Germany developed marginally successful resonant sound wave machines to attempt to destroy 'things' at a distance without affecting the surrounding structures.
or way more simply blowing over a bottle top and getting a note/standing resonant wave.
but i'm just a welder these are only guesses.
darren
Parent - - By CWI555 (*****) Date 10-26-2007 18:27
For "just a welder" as you put it, you have a very good grasp of the concept.
In reference to "bubba the seminar instructor" who stated welders didn't know anything "" bubba wronnng againn". (said in tone of the professor from the water boy movie)
Parent - - By Tommyjoking (****) Date 10-27-2007 06:25
Gerald it would be an honor to have you in my shop anytime and you would be most welcome...knowing the security guards vices with treats probably won't hurt our chances .  The whole current/magnetism  theory seems to have merit.  But you hit on a valuable point with resonance.  Nikola Tesla late in his career did many structural experiments regarding mechanical resonance of materials and structures....he had many claims  which most sadly were not properly documented.  But his theory was that all materials and /structures have an inherent frequency of vibration that could potentially destroy them with self amplification (said simply please forgive me).  Tesla also worked with resonances with regard to electrical currents.   Maybe on some of these materials we are finding a trigger to some resonant harmonic that is molecularly inherent to the material itself.   Now having said that.....I still believe that perhaps the heat input during welding may also be triggering some kind of resonance....after all we are forcing molecules to rearrange themselves and their atomic bonds at a rapid rate....could this process in itself also not cause some sort of inherent mechanical resonance to come forth and present itself thru a structure?  I would say do not discount the effect of sudden heat expansion and all other things associated with the atomic bonding going on in a given weld.    Dang it guys does anyone know a good physicist or physics prof we could have look in on this???  lol

Best Regards
Tommy
Parent - - By darren (***) Date 10-27-2007 06:52
although i was being glib tommy the answer is as ive stated above. even in a model pure dc mode (not taking into consideration in the real time rectified current for this example) the delivery of electrons (a given unit) over a period of time is in itself a frequency and the electron has an inherent frequency as well. all things that exist have an electro magnetic frequency and the physical proof of them not existing is to have no electro magnetic frequency.0 Calvin is by definition the point at which emf ceases ( no not electro motive force force for you purists out there although that would be non-existent as well) there is interference between two frequencies , the parent metal and the current( at least). this is the frequency that becomes apparent to you when things boogie it is the frequency of additive and subtractive wave structures within the item.
this is actually very basic physics and a first year physics major or an attentive high school physics amateur would support this hypothesis.
darren
back to you up in the booth gerald
Parent - By Tommyjoking (****) Date 10-27-2007 07:07 Edited 10-27-2007 16:39
key word HYPOTHESIS.....dang did someone step on a nerve here?  (edit of other comments that won't add anything to the subject)

That particular part when thinking on it has a curiosity...that "reliable trigger" weld is a fillet on a piece of of 1/2 x 4 barstock that has been heavily machined to a piece of square tubing....that tubing could act as an amplifier/conductor of any type of sonic/mechanical wave induced.  But you bet it will set up vibration with regularity.

Best Regards
Tommy  
Parent - - By CWI555 (*****) Date 10-28-2007 07:46
Sometimes I wished AWS forum had the ability to reply to two people at one time. It would make it less complicated.

Tommy/Darren

This subject is extremely complicated to say the least. It's also not fully understood, even by the brightest minds in physics. Resonance is broken down into three primary categories:
1. Acoustic
2. Mechanical
3. Electromagnetic

Acoustic is a category because it can be caused by either mechanical or electromagnetic vibrations. welders use electromagnetically induced acoustics to know "when it doesn't sound right". They may not know the specifics of frequency, period, etc. but they know what experience has taught them.

Of course mechanical acoustics is a speaker, a hammer fall, etc. One of the earliest known NDE methods applied to working of metals is the striking of the hammer on the anvil to "ring" it. The surprising part to me is, for something that's been around for several hundred years, there is very little hard science to be found on it. Bad metallurgy, flaws, temperature, and other factors will make a bad ring, but finding definitive answers is no easy task.

As for heat input:
Heat input will definitely set up vibrations. Even the lonely hydrogen atom will vibrate at a series of distinct frequencies known as "normal mode". The lowest normal mode is known as the fundemental frequency, with the normal mode frequencies above the lowest ones being known as overtones.

As for destructive and constructive:
Destructive and constructive interferences typically depend on a waveforms being either in phase or out of phase.
If two waveforms are traveling together with the same *amplitude, frequency, and wavelength but have started from the oscillation source at different times they will experience points at which they constructively interfer and effectively double their amplitude, and times when they are out of phase, and cancel their amplitude (destructive interference).

This is in contrast to a standing wave. Using the * data except that the waveforms are traveling in opposite directions will create the appearance of a wave that stands still.

Doubling of amplitudes In constructive interference I don't think would be enough to initiate the "boogie". I suspect that it's pent up energy in a standing wave or resonance that when bumped or otherwise acted on by an outside force releases this energy potential in the form of mechanical motion.

In the electromagnetic realm; one form of resonance is known as a Schumann resonance. Where electrical discharges (lighting strikes) create global electromagnetic resonance in the emf ELF (extremly low frequency between 7.4 and 45 Hz) as the area between the earths surface and the conductive ionosphere acts as a waveguide for it. (also the basis for Teslas work on wireless energy transmission, something that has been picked up again with the idea of transmitting power to the earth from solar arrays). The U.S. power grid oscillates at 60 hz, which is close to the 7.4 hz fundemental frequency 8th overtone. (59.9 hz). If you hooked up a very low frequency reciever, you could hear this translated to acoustical noise. Under the right conditions, it's been known to play havoc with ham radios. It's also one of the technical problems to be overcome before space based power transmission can occur.

As for physicist first year, high school or graduate:
Chasing all these factors to their eventual ends puts you into the edges of known physics, Einstein's special theory of relativity, Lorentz transformations, quantum mechanics, and a whole host of other sciences, theories, postulations and BullS###.

to sum that up, there is no physicist that can explain it definitively or group of the same. They can't even give a definitive answer on what electricity is, or light or magnetism/gravity and a myriad of other things. All they can do currently is measure it's known effects. Using light for example, Newton (Corpuscular Theory) says it's particles traveling in straight lines, Maxwell (electromagnetic theory) says light is electromagnetic wave form, Plank (quantum theory) says it's photons, De broglie and Heisenberg (unified theory) says it's a mix of Maxwell and Plank. Therefore I cannot say definitively that it is not magnetism, but it can't be stated that it is either for same reason. I believe it is not, but that is < 100% sure.

The moral to the story is, all we can do is measure the presence of and effects of. Stating what it is for a fact would be to state a lie as no one knows to date. What makes a resonance frequency, what atomic/chemistry values define it, and a myriad of other factors. The only thing that is relatively sure is that it's not a normal occurrence in carbon steels. that again is the reason for thinking sound/mechanical energy rather than magnetism. Something in the atomic structure of the carbons maybe the fundemental frequency of the metals atomic structure doesn't play well with the theory, whereas the TI and NI welds do.

Tommy I'd be glad to, just need to know what flavor the guards drink or eat.

Thats enough boring of you good folks for one night.
Regards,
Gerald
Parent - - By darren (***) Date 10-28-2007 20:47
I accede to your obvious great skill and understanding of the topic, although more eloquently stated and obviously better remembered, your response does iterate what i was trying to state in a simple way.
science is never definative but is footholds on reality from which we reach for the next possible place to test for its fastness and proof before we leave the safety of the last comfortable spot and risk moving to the next step in the climb/endevour to conquer the mountain of ignorance that we call sceince.
within sceince like all aspects of life we must use some boulean logic to ascend. of course the most comfortable of the choices are yes or no; maybe, ifthan and therefore, become 
the realm of extrapolation, interpolation, hyperbole and conjecture. again as the yes no forms the foundation of science it is the others that lend understanding to things that are postulated but not proven, like a kite proves the wind but does not avail us to the sight of it.
without knowing the exact circumstances that developed the 'boogie' it can be reasonably assumed that it was either a single wave structure resonating within the structure, or a multiple wave system that are interfering with each other and releasing the energy in a visible form.
i was implying that these or in fact any postulates can not be proven entirely( Plato's hypothesis that the only thing we can prove is that we are receiving some sort of code{thoughts} as an individual and that we cannot prove the source of that code or that any one else is receiving that same code or that the code does not infact just cycle within our own consciousness {beginning of the quantum/string/brane theory}) but to move forward with our understanding we must accept truthisms, axioms, paradigms and models that are not completely defined.
what i was trying to imply was that there are some basic physical studies that mostly explain probably within a reasonable margin for error what was happening and that it in fact is not the welding spirits.
i realize that none of this is new and i am just reiterating what we all already know so as to clarify that i was not trying to wholly correct but like in all things trying to be mostly correct.( hell if i could just do that alone on a day to day schedule i would be king)
thank you for enduring my diatribe as well as  the opportunity for the banter,  also being able to  put forth a loquacious and somewhat pedantic response ultimately proving my anal
character which is as we all know is the foundation for a good welder.
please forgive my misuse of the 'standing wave' concept gerald and it wasn't boring always nice when someone tells you your fly is open, proves they really are a friend.
darren
Parent - - By CWI555 (*****) Date 10-29-2007 04:21
"loquacious and somewhat pedantic response"

You trying to tell me I am mouthy and anal retentive? LOL
Parent - By darren (***) Date 10-29-2007 08:53
no i meant me because its the only two big words i know.
Parent - - By Stephan (***) Date 10-28-2007 18:46
Heavenly Goodness Ray!

I must say, if you wouldn't be already a great CWI and Welder you would be surely a great Researcher!

Hats off to you Ray - and of course to all the other fellows!

What a thread... great!

Best regards,
Stephan
Parent - - By Tommyjoking (****) Date 10-29-2007 09:36
ok to make the drum circle complete here......Darren I am not ignorant of simple physics, the math or the theories.   Thats kind of the problem I reserve faith for one person only....without mathematical proof of anything else...well its just theories. To proclaim the root cause and answer here is foolhardy without measurement and some form of proof of result....I doubt anyone is expecting it....it's just a nice subject with which to exercise the mind armed with what experience and knowledge each of us have.   Physics is a hobby for me and I dearly wish I had the aptitude in advanced mathematics to practically learn the serious mechanics of it....without the math its nothing more then concepts (guessing in the dark if you will).   

Gerald very well laid out response and intention and BTW thank you for the thought behind it.   AND you are very right in the general assumptions of physic theroies which seem to be accepted as facts with regard to molecular sciences....we just got no better explanation but little of it is proven.....we can manipulate much but have poor understanding of whats actually happening when we do so.    Its still very much a fascinating conundrum isn't it.  Just an offhanded thought ...I seem to remember the carbon molecule itself having some sort of special effect/interference with magnetism...maybe senility .... I just seem to make that connection ...can't quite remember what it was.   At any rate Gerald no worries with the Security personal ....we would make it so if you ever decided to visit. 

Stephan I am almost shocked that you have not presented us with ten papers on this subject already!!!!!!!!   LOL!

Best Regards to all
Tommy

p.s. Great Thread!!!!!!
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