Welding Tips and Tricks

hello everyone, My name is keeyen Pang from Malaysia.
In searching more info about the Multiplaz 3500, I found this amazing forum.
I found the Multiplaz 3500 during my recent trip to the Canton Fair. I think it is a very useful tools for my workshop. What make me a little worry is the cost of those consumable item like nozzle and cathode. If the service life is only 10 to 20 hours as per manual, the cost to replace them may not justify for cutting job. This is because in our area a cylinder of industrial oxygen cost less than 20 USD and household propane is less than 10 USD for 15 KG.
I think the nozzle should be quite simple to recondition but don't know about the cathode. I hope to hear from the idea of those experience user here. Thank you very much.

Intrajasa.

Welcome to the forum.
After reading your post, I am eager to hear what the members have to comment.
What welding processes do you utilize the most in your shop?

Alexa

I'm not a big fan of using the MultiPlaz 3500 for cutting metal.

(Good fusion welder though.)

Reconditioning the tips shouldn't be too hard.
It's only the orifice that gets worn out or 'out of round'.
The cathodes have a hafnium insert and would be harder to recondition.

My workshop is more on mild steel, stainless steel and cast iron welding
I've skype with the factory rep today. They told me the service life of cathode is about 150 hours and nozzle is 40 hours. Now I would like to know anyone here have some actual figure base on their experience.

For myself, I cannot answer your question. I haven't had the machine long enough to make that evaluation.

intrajasa wrote:My workshop is more on mild steel, stainless steel and cast iron welding
I've skype with the factory rep today. They told me the service life of cathode is about 150 hours and nozzle is 40 hours. Now I would like to know anyone here have some actual figure base on their experience.

Hey,

BTW whats going on in the photo .

Mick

It's a crucible, used in metal casting, for the manufacture of small parts.
I bought all of Stephen's books. http://stephenchastain.com/store/

No need to waste all of the turnings from the lathe.
Melt them down and make something with them.

weldin mike 27 wrote:Hey, BTW whats going on in the photo . Mick

Hey,

Cool , thats what i thought.

Thanks, Mick

Hi all.....has anyone ever heard of the atomic hydrogen torch, or to give it it's real name The Langmuir Process invented in the 1920's.

Having read a lot about the origins of the invention and how it works, I have to come to the conclusion that the Multiplaz 3500 is an Atomic Hydrogen Torch rebooted in the 21st century.

If this is so, then the Russian invention is purely based on the Langmuir process and is a spin off.

Google the process and comment.
Ian.

There are similarities, but it's a steam plasma torch.
http://www.plazarium.com/products/steam ... arium-sp3/
https://www.youtube.com/watch?v=Jyf1Kju ... bm6qWD6J9e
http://www.youtube.com/watch?v=oiAAASySa1s

Hi, the similarities are that the two methods use hydrogen, which in the Multiplaz unit is derived from the H2O....the Oxygen burning off at disassociation in the arc, but the Hydrogen undergoes the same splitting into H2 and Hi etc due to the arc.....same process, one has two tungsten electrodes and the other a copper nozzle and a Hafnium cathode, both use high voltage of around 200 to 300 volts with amps around 20 to 30 to achieve a plasma.

In the atomic Hydrogen torch the temperatures are rated to get up to 3,500 deg C and in the Multiplaz unit the temperatures are stated to get to 8,000 deg C.

I can only think that the increased temperature claimed by the Multiplaz is due to the Oxygen burning after splitting at disassociation.

The Multiplaz is unique in that it uses the on board supply of the H2O combination to replace the external Hydrogen supply as used in the original Atomic Hydrogen torch/Langmuir process of the 1920's.

There is also an added alcohol content for the multiplaz, for what purpose I do not know, but it's stated to be necessary for welding, and not for cutting.

The big difference in the two torches are, that the Multiplaz requires an earth connection to do welding, that is the job is connected to the earth electrode to enable the high frequency to carry the arc to the job in Mode #2, but for brazing, mode #1 the earth connection is not necessary.

In the Langmuir torch the two tungsten electrodes are connected to the two output cables of the power supply and are manually touched and adjusted to give the arc with the Hydrogen blowing between the electrodes to cool the tungstens and also form the plasma.....there being no earth connection.

Attached is a pic of the Langmuir torch.
Ian.

Billbong,

A question I suppose the anwswer is obvious to, but I wish to be sure I understand correctly.

The hydrogen supplied to the torch will be H2, as that is how hydrogen occurs in nature at Earth's conditions. The conversion to plasma then breaks the bond, creating atomic hydrogen?

My understanding of plasma suggests a further breakdown, to free protons and free electrons.

Interesting subject!

Steve S

The electric arc efficiently breaks up the hydrogen molecules, which later recombine with tremendous release of heat, reaching temperatures from 3400 to 4000 °C. The hydrogen gas is normally diatomic (H2), but where the temperatures are over 600 °C (1100 °F) near the arc, the hydrogen breaks down into its atomic form, simultaneously absorbing a large amount of heat from the arc. When the hydrogen strikes a relatively cold surface (i.e., the weld zone), it recombines into its diatomic form releasing the energy associated with the formation of that bond.

A thought came to mind... A home heating system, powered by wind and water.
The wind generator provides the electrical current required to create the steam plasma.
I'd be curious to know how efficient a system like this would be?

Hi, in terms of efficiency, that would be determined by the output derived from the input to achieve the output.

That means if you were planning a home heating system and the plasma/water heating path was the one of choice, you might be using more current to produce the high plasma temperature for a shorter period of time, but along with the exotic consumables that enable plasma to occur, would be more costly even though the same amount of heat was consumed.

You could use a plasma source to heat water very quickly for a short period of time and then switch off for a longer period until the water temp dropped and it switched on again, but you'd get more losses from insulation leakage from the water storage tank.......direct air heating from plasma would not work, unless you utilised a heat bank of heat absorption material, like large cast iron blocks etc with air passing through them.

The alternative would be that if you just shorted two cables through a resistor surrounded by water, you would have what is currently being used in your electric kettle which is cheap, simple, long lasting, self regulating and state of the art.....(and no wiz bang circuitry to fail).

I don't think even going to a small simple arc furnace for heating purposes would be very practical, even if it was doable.

The Multiplaz heat production does so with the consumption of a fairly large amount of electrical energy input, but as the end product is far greater than an equivalent Tig, Mig or stick welding method, the consumption to achieve this is tolerated.......there is very little loss in making the plasma as the input power is converted into a useable output product that is controllable for the purpose, and as in all energy sources the part that is usually wasted, IE heat, is now the end product per se......the heat used is relative to the absorption ability of the material being heated, and probably 50% of the end product, as in all welding sources, is wasted by being radiated and deflected to the atmosphere.

Plasma versus conventional welding methods can be likened to an internal combustion engine that by the latest and ultimate design technology achieves the maximum from the fuel it burns, and in that is unable to produce more power from the fuel supplied.

In order to increase the power output, some of the exhaust waste emissions are used to force a higher volume of fuel mix into the engine and so you get a bigger bang with more fuel consumption, but for more bucks, which is the only way to get an increase in power from the same package.

The Multiplaz is in this class, in that going to a plasma production the end product (heat) is far in excess of that which can be derived from just pushing the input energy through a transformer and shorting the secondary windings with an electrode, but it comes at a price.

Even if you doubled the size of a regular welding outfit, the heat of the arc cannot be increased above the melting point of the electrode, whereas the plasma method will give you huge increases in the welding heat capability.
Ian.

I believe that we are just starting to see the advances in plasma technology.
http://www.peat.com/plasma_torches.html
http://www.sciencedaily.com/releases/20 ... 120522.htm
http://www.alternrg.com/waste_to_energy ... a_torches/

Wether or not we'll be able to enjoy the advances is up to the industry, but more so the potential users, who must look beyond the conventional approach to multi method welding and cutting.

I think there is a huge need for a mini version of the Multiplaz, something that will allow finer work than the current torch is able to do....or maybe that's just me, but on a recent job welding an aluminium frame for a water pump base to mount my spa pump on, I had difficulty in not melting the metal in wholesale quantities.......LOL.......that is while the temperature would with ease reduce the aluminium to a large puddle, the ability to form a neat bead along a seam was difficult without melting the material into holes and blobs, but it got there.

I managed to weld the frame, made from 30mm X 30mm X 3mm thick aluminium angle, mitred corner joints etc, but it was quite difficult to get the weld pool to form without actually melting large areas into a big blob.

Cleaning and preparation was as per normal practice, using a powder flux to coat the filler rods, which were made from 6 strands of 1.2mm aluminium Mig wire, twisted together to form a 6mm thick rod.

The end product, while quite adequate for the job, by appearance was not up to "embroidery" standards as practiced by most Tig welders, that is it will hold together without the fear of breaking apart or cracking, but no sense of appearance was achieved, and for some reason for welders the appearance is the judge of a good job.....fail in the appearance book and the job fails.

Well that may be so, but I am able to weld aluminium with the Multiplaz and ensure it will be functionable for the purpose, even if not pretty, which many people cannot do with Tig, Mig or stick equipment.

BTW, the job did clean up reasonably well with my Dreadnought file and passed the bang on the floor test with flying colours etc.
Ian.

Ian, you can use the 'cutting nozzle' as a welding nozzle
and dial down the voltage to control the flame.

Hi, I hadn't thought of that.....it makes sense though.....most of my "work" is smallish jobs, I bought the unit because I liked the idea of plug in and fire away etc, no bottle gas to worry about.

In the first photo of the cutting nozzle doing it's thing, the tiny flame would appear to do all that I said was needed to replace Tig welding for precise beads and seams etc, especially on Aluminium where you need that intense point of contact heat input without blanketing the whole job with a volcanic heat front.

This is something that the Dillon/Henrob oxy acc torch claims, and works in practice as I have used one.

As soon as I can do a test I'll post some results with the cutting nozzle for welding, probably not today or tomorrow, but it will happen.

Thanks for the "tip".........pun intended.....LOL.
Ian.

Also, if you are trying to lower the heat, don't use alcohol in the mixture.
The torch is fully capable of welding without it and the heat is easier to tame.
I've contemplated making up a custom set of tips, just like any other torch.

I use the Henrob/Cobra/Dillon oxy/acetylene torch as well. Its my favorite.
If you can gas weld aluminum with it, then the MultiPlaz is a no brainer.
https://www.youtube.com/watch?v=FTD6bcFpRVs