Isopropyl alchohol

[Rob Taylor]

I just found some isopropyl alchohol 99% for $6.47 per litre Canadian in the Walmart Pharmacy.

This raises an interesting new Multiplaz user question. How pure should it be? Where is the best place to procure it?

I tried looking for ethyl alcohol bit it seems to be a little hard to get. Strange as this stuff should be cheap, considering they cut our gasoline with it.

Any ideas for where and what to get to use with the Multiplaz?

[Iwerk]

I've been using water from my de-humidifier without alcohol for most of my welding.  

I have isopropyl from the local pharmacy but I've found that I don't need the extra heat, as the torch gets plenty hot on pure water. 

I've also experimented welding with the cutting nozzle (instead or the welding nozzle). 

When welding small items, I use the cutting nozzle on only the lowest inverter settings.

[Rob Taylor]

Thank you for the information Iwerk. That's good to know.

I had imagined the alcohol was more for reducing the oxidation of the weld than for the additional heat though.

But I got my information from part of the Multiplaz 3500 Evaluation by larry lee on the welding tips and tricks forum.

You can see the whole 14 part evaluation by using this search URL:
http://forum.weldingtipsandtricks.com/search.php?keywords=Multiplaz-3500+Evaluation%2C+Part&sr=topics&submit=Search

It was part 2 though where he says:
"Using just water vapor for the plasma gas works fine for plasma cutting. But, as mentioned earlier, water vapor alone gives a slightly oxidizing gas output. For soldering, brazing, and welding, one wants a neutral or slightly reducing shielding gas to minimize the oxidation of the workpiece (think in terms of an oxyfuel torch). In the Multiplaz torch, the plasma gas and the shielding gas are the same. The gas can be made more reducing by changing the composition of the fluid that is evaporated. Using the analogy of the oxyfuel torch, one can make the gas more reducing by increasing the amount of carbon in the fluid. But again, there are several constraints:

1. Solubility of the additive in water - the additive must be stable and must not separate out over a wide range of temperatures.
2. The additive itself must not be hazardous, and it must not produce hazardous fumes when injected into the plasma.
3. The additive must not react in undesirable ways with the torch components, nor with the workpiece.

The best additives were found to be “oxygen-containing hydrocarbon compounds, in particular, alcohols”. The Operating Manual for the Multiplaz-3500 specifies ethanol (also called ethyl alcohol or ethyl hydrate). The use of methanol (methyl alcohol, methyl hydrate, wood alcohol) is specifically warned against, because of the greater flammability and because of the hazardous fumes produced in the plasma. Isopropyl alcohol can also be used. The longer the carbon chain in the alcohol, the more reducing the shield gas would be expected to become, based upon the chemistry in the plasma."

But I do intend to try your ideas especially for welding the small items as It would be nice to not have them melt to nothingness.

Take Care,
Robert Taylor