Thread: Plasma foot in mouth time

Originally Posted by Andy Mac

Accept the honest apology Shane, and stop going on about it.

Gents, to be fair, may I suggest that you re-read the original post. It was NOT an apology to Shane, he was specifically excluded.

Originally Posted by Groggy

Gents, to be fair, may I suggest that you re-read the original post. It was NOT an apology to Shane, he was specifically excluded.

My reading of Grahame's post is that he said that he didn't feel he had to apologise to Shane. OK. That may be how he felt, but he did own up to not having been right - that in substance is an apology.

I reckon Shane should have accepted that Grahame had publicly stated that he had been wrong as enough, whether or not it was an apology. instead Shane's post threw what Grahame had said back at him and made statements about Grahame and his knowledge in the area that don't seem to me to be either accurate or fair.

Attitude is important. You said it! ,Shane it was yours, so cocksure and arrogant that prompted me have a good look at what you where doing on the board in this forum and in others. On three occasions you have joined in and answered a contributor’s post (that’s fine ,I have no problems with that ) but then proceeded to hijack the post with your ideas/ projects. The fact you don’t post your ideas/projects as stand alone posts , says something to me.
It is you that posted them in an open public forum where your ideas or concepts are open to public scrutiny and discussion. When a contributor disputes with what you have said, you get ,to say the least, quite upset. And I am the one with the ego problem?

And then you proceed to tell granny how to suck eggs.

A bit of name calling by you and an obscuring of the proper facts amongst some URL references has abjectly failed to change my opinion on the viability of this project.

Bullxxxx, bother and bluff ,does not work on me.

Originally Posted by 2shane
I want to build a chemically inert gassed plasma cutter, using steam as the plasma gas, because I figured that the steam at the right pressure and temperature will work lots better than straight air, and far far far cheaper than argon.
And it will work for a whole heap of good reasons.

Steam, water or oxygen and hydrogen are not inert and here’s proof.
Here’s a cut and paste from the net .It took I minute of “research” Reference - inert gases.

http://www.encyclopedia.com/doc/1E1-inertgas.html
Inert gas or noble gas, any of the elements in Group 18 of the periodic table . In order of increasing atomic number they are: helium , neon , argon , krypton , xenon , and radon . They are colorless, odorless, tasteless gases and were once believed to be entirely inert, i.e., forming no chemical compounds; however, some compounds of these elements have been produced, i.e., fluorides of krypton, xenon, and radon. The low chemical activity of the inert gases is due to the fact that their outermost, or valence, electron shell is complete, containing two electrons in the case of helium and eight in the remaining cases. The inert gases are sometimes called the rare gases, although argon is not rare (it makes up about 1% of the atmosphere) and helium is commercially extracted from natural gas and the atmosphere.
Can’t see mention of water or even Oxygen + Hydrogen there.
Both gases, Shane do not qualify as inert. So from the very start you have no basis at all to argue on. That is substantiated basic science not the baseless conjecture by me that you are so willing to accuse me of.

I am very well aware that water/steam was used as a SHIELD EXTERNAL TO THE PLASMA STREAM. A reminder : you said “ using steam as the plasma gas “
Plasma only exists in the central column of a plasma unit-You are the one who should get your facts correct OK!

Having been a member of both the AWS and WTIA( Australian Welding Institute –at that time) earlier in my career I received monthly magazines which kept me up to date on all advances in welding including plasma technology.
What you have not found in your so called quote “cross referencing with the real world” was that the real world found it a dud years ago mainly due to a severe fume problem.

Too many of the combinations of different gases and water (steam) caused nasty toxic gases to be emitted particularly with nitrogen.
It was mentioned a lot in the articles, about twenty five years back by AWS and reprinted in AWI late 70’s early 80’s mags. No doubt that fact is probably is omitted in today’s web based articles now to provide little or no fodder for the American lawsuit industry.

Snip <After I had thought up the idea, I went and cross referenced it with the real world and found out that yes steam can be forced into the plasma state and used as a cutting medium,> This is what is an unsubstantiated reference is Shane – there is not a specific mention of it below– specific cut and paste then the URL reference please.

Again - Snip < 5. I knew that wet steam (virtually pure water) ought to be able to be
induced to create a plasma, with the most elementary of electrics and igniters.>

Fifty thousand volts is a basic ? No Shane we are not piddling around with 240 volts . Stupidity Kills and Absolute Stupidity Kills Absolutely Spare me! You exhort young Gags to practice electrical safety but are prepared to dabble in an open power source with around 50kv potential. Hardly an ideal role model Shane .

You seem have set a foot in both camps referring to your thoughts on steam in or out the plasma stream.

SNIP < And this is completely different to using steam as THE cutting gas.> Either the steam surrounds the plasma column or it does not- You do not know.

But later YOU say SNIP < i) This the very reason why steam is NOT used as a plasma cutting gas - and the information about it is very scarce. >

And you can be sure Fronius won’t about to tell you zip about it, any time soon .

Make up your mind fella!

Your bulk URL’s don’t prove anything at all. (Please, everybody get in and do read them, I obviously can’t read anything properly, according to our Shane )

http://www.sppusa.com/reference/white_paper/wp_pc.html

http://www.iupac.org/publications/pa.../7403x0429.pdf

Not one scintilla of evidence of anything relating to steam INSIDE of a plasma column at all in those references. Let’s get it crystal clear Shane you talked of STEAM.
The URL’s you posted, are just general , (not specific) references to water shielding a process external to the plasma arc.
Any body from here that clicks on the links and reads them will now know that.
Water injection a now discarded process , long ago thrown out ,for reasons I’ll go to later.

As I far as I can read, NOT ONE of your url’s, contain valid statements about STEAM IN THE CENTRAL PLASMA STREAM to support the flimsy argument that you display any real grasp or basic knowledge of the statement you made in that original post. Water injection ,Shane, referred to in your references is external, Shane, external to the plasma column.

You saw the term water injection and concluded it meant in the plasma stream. Well it didn’t. It referred to injection into the plasma head and you were totally wrong,AGAIN.

My doubts center on anyone’s ability, let alone yours, to bring such a concept, to fruition, in the confines of a home workshop.

Furthermore my belief of your ability to do so in your home shop is substantially challenged by the display of your appalling lack of knowledge regarding basic power sources as follows.
You wrote in Gags thread and posted a picture of your single phase stick welder which is a constant current power source.
SNIP <This will give me stick in AC or DC electrode Neg or Pos, same with the TIG, and HF overlay... (welding aluminum)
I will also build a MIG wire drive for it. My own CR roller design.>

There you go.! I had some measure of belief , right up until that point, before you are going to build your Mig wire drive CR roller.
That’s when my BS meter rang. Ding!!,ding! Ding! Not for that that particular power source , Shane .Oops! for starters there is no way to control the voltage output. Mig power sources are entirely different to stick welders.
I would have expected someone who is so deep into plasma design to have figured out that one!

You counseled Gags to go to TAFE .Did you not go yourself or were you away sick on the day they taught this :

Constant Voltage power source
A Power source that, when attached to the power inputs of a welding rectifier, produces the same current for all values of bridge resistance.

Constant Current power source
Power source that, when attached to the power inputs of a welding rectifier produces the. same voltage for all values of bridge resistance.

(A cut and paste from the ESAB site follows in italics )

The Power Source Direct current, constant potential (voltage) power sources are used for most mig welding This contrasts with tig and stick electrode welding which use constant current power sources. A mig power source provides a relatively constant voltage to the arc during welding. This voltage determines the arc length. When there is a sudden change in wire-feed speed, or a momentary change in arc length, the power source abruptly increases or decreases the current (and thereby the wire burn off rate) depending on the arc length change. The burn off rate of wire changes automatically to restore the original arc length. As a result, permanent changes in arc length are made by adjusting the output voltage of the power source. The wire-feed speed, which the operator selects prior to welding, determines the arc current (see Fig. 3-1). It can be changed over a considerable range before the arc length changes enough to cause stubbing to the workpiece or burning back to the guide tube. Power Source Variables The self-correcting arc length feature of the constant voltage welding system is very important in producing stable welding conditions. Specific electrical characteristics are needed to control the arc heat, spatter, etc. These include voltage, slope, and inductance.

The above is the reason, substantiated proof,if you will, that the wire feeder will not work on that CV power source.
Yes! there are combination stick tig mig units like the Millers but your stick machine is definitely not a combination unit .Your power source is a constant current and nothing will alter that fact.

The purpose of this board is to help each other Shane. I would hate to see any of this crap between you I , damage or degrade the wonderful sense of camaraderie and willingness of the contributors to give what ever help needed to one another. This entire forum is truly unique place for that.

I did find it a bit rude of you,after initially offering some good advice (great ) that you then jump in with your welder idea not related to his( Gags) question.

In case you don’t realize it, we should all have a duty or care not to mislead or misinform readers with any sort of advice (or even ideas ) that they may take and cause harm to themselves.

Your petty tirade has no effect on me, by now most of the readers who saw that post will have formed their own opinion of you by now.

Most certainly, I will happy to offer a written public apology to you when you prove me wrong in my conclusions about your own ability to produce a viable cost effective working plasma cutting unit with (take your pick ) steam as a feature of either the central plasma column or surrounding the central plasma column. You will find that ultimately it will cost you well in excess of the purchase price of a current working plasma unit to do so.

The shame of it all Shane is that you probably may some good ideas. Everyone has them. Had you presented yours in an appropriate way, I am sure more of our forum contributors would have been better disposed to help you.

And what I do with my attitude is your problem.
My attitude to you, Shane, is put up or shut up.

Grahame

Grahame,

I'm a bit out of my weight division here, and know nothing about the subject (which I'm sure some would say doesn't make me alone ). Welding and cutting is what I get someone else to do, but one day I'll give it a go, so have read all your previous posts with great interest.

Question:

In my youth, (as far as I can recall) a friend was seriously burnt after accidentally igniting a big lump of magnesium while welding a chassis component (remember when "alloys" on racing cars were "mags" and mostly magnesium?).

Not wanting to cause a fuss, he threw water on the fire, and suffered horrible burns in the resulting explosion. I'm sure a lot of it was simply steam, but one theory at the time was that the heat from the magnesium was so intense that the water turned back to oxygen and hydrogen, and maybe they aren't the best things to throw on a fire.

Is that what's happening in the process we are talking about? Is the water jet becoming an oxy-hydrogen jet?

OR am I completely lost?

Cheers,

P