[sunppeli]

I'm looking for a water-cooled torch for my TIG-welder. This:
http://www.ebay.com/itm/200Amp-WP-20F-2 ... 19c8d68c06
looks like a pretty good deal. I'm wondering how a WC-torch body can be flexible? Do the flex torches cool down as effectively as stiff bodied ones? Are those Chinese torches any good at all?

[racingparts]

they are very good
i use 2 from them, 1 water cooled and 1 wp26 normal
in 2 years never had problems with the torch

i buy from them all i need for my workshop,they have the best prices

[sunppeli]

Thanks for the reply!

Is there is big difference in heating between the big and small torches? I would be AC welding at about 150amps max.

[Otto Nobedder]

You'll never feel the torch handle get warm with a wp20 at 150A AC. A few years ago, I welded a ton of aluminum pipe on a job, averaging 180A, all day. If your cooler can handle it (move enough water, have enough cooling area, that torch will go 250A AC.

Two tips...

Don't flex it any more than needed for the job. Regularly flexing it to it's extremes will work-harden the lines, and cause early failure.

For AC, don't use tap-water or automotive anti-freeze/coolant. Buy a couple of cheap gallons of distilled or de-ionized water, and if you must have an anti-freeze for your climate, buy the "low conductivity" kind, available from any good welding supply.

Steve S

[sunppeli]

Thank you a lot!! I will order the 20-model torch.

[Otto Nobedder]

Hey, if you don't mind, post your own review, once you've fused some metal with it!

Steve S

[sunppeli]

I will! It should arrive in around 3 weeks.

[racingparts]

if you go with the water cooled one you'll have 0 problems
it;s not the best in the world but it does the job great

[sunppeli]

I ordered the 20-style water cooled torch with some gas lens parts and electrodes. I've also built a 10-liter aluminum water tank for the cooler. I still need a pump. How much flow from the pump I'd want?. Do I need an external radiator? Is it good enough if I just weld some fins on the tank and maybe add a small afan?

Lots of questions again .

[Otto Nobedder]

You should be fine with just a tank and pump, unless you start doing production-level welding. Stick a cheap-o thermometer in the tank, and check it now and then to make sure you're not getting above about 150-175*F (You want to make sure the torch never gets too warm to hold comfortably in your glove for extended periods). If you get too warm, then consider adding fins and fan. IF you find you need a heat exchanger, a heater-core from a car or a condenser from an old AC are dirt-cheap pre-fab solutions.

A simple fountain pump, capable of maybe 5GPH tops will be plenty. The lines you're pushing coolant through are small.

The common arrangement is to supply water to the torch through the "plain" hose, and return through the hose that carries the electrode wire.

Steve S

[Otto Nobedder]

Okay. Just noticed you used metric units in your question.

If the tank stays under 80-85 *C....

and a fountain pump of up to 20 LPH...

[Otto Nobedder]

BTW, I rcommend the fountain pump because it's centrifugal, rather than positive displacement. A positive-displacement pump will bust a line (or self-destruct) if a hose becomes kinked or gets stood upon, or the line becomes blocked for any other reason.

Ideally, the pump should be matched to what the line can carry... Too high rated a pump will cavitate if it can't move the volume it's designed for, thus my 20 LPH max. Half that may be fine; I've not worked it out.

Steve S

[sunppeli]

That's a huge help, thanks a lot!!

[sunppeli]

Looks like the first job I'll be doing with the new WC-torch is aluminium and it's going to have to be done using tap water as coolant.. Should I rather use the air-cooled torch? Someone mentioned it's not a good idea to use tap water when welding on AC.
This is because my cooler still isn't finished and I got no time to work on it before I do this job on saturday...

[Otto Nobedder]

Looks like the first job I'll be doing with the new WC-torch is aluminium and it's going to have to be done using tap water as coolant.. Should I rather use the air-cooled torch? Someone mentioned it's not a good idea to use tap water when welding on AC.
This is because my cooler still isn't finished and I got no time to work on it before I do this job on saturday...

Depends how hard your tap-water is. If you develop bathtub rings, toilet rings, and soap-scum easily, that's a sign you have a lot dissolved minerals, usually calcium and/or magnesium, which (like salt) dissolves as free ions. This is where the problem lies; Free ions conduct electricity (think electrolysis).

A water softener is NOT a fix for this; it's an ion-exchange where Ca and Mg are replaced with sodium.

I'll point out that "superflex" lines are somewhat more succeptible to this than the more rigid nylon hoses.

Steve S

[sunppeli]

So when talking practically, it leaks the electricity to the water? Does it ruin the hoses or affect the welding procedure? Is this only on AC?

[Otto Nobedder]

Depends on the torch lead configuration. Some cheaper torches have a cable running in the return water inside the hose. Here, you may notice lower power output than expected for a setting, on either AC or DC. These lines are not damaged by the problem.

Other torches have the cable wrapped co-axially around the return line, typically in superflex style torches. In this case, the rubber hose between the water and the braided cable becomes the "dielectric membrane" in a capacitor. The higher the conductivity of the water, and the higher the frequency of the HFAC, the more potential there is across the membrane. These torches can be permanently damaged.

Steve S

[sunppeli]

This is the setup I ended up using for the cooling:
http://imgur.com/KqEc71J,6bsIFEE,IGr1YS ... ,ucbcY2n#0
I had a small 12v submerged water pump on a bucket of distilled water, so no tap water used. Maybe not the most compact cooling system but it did the job perfectly! I did maybe 3 hours of nonstop welding (5+ hours working time) and at the end the water in the bucket was only slightly warm! I welded 2,5mm alu on AC at 100amps max.
http://imgur.com/KqEc71J,6bsIFEE,IGr1YS ... ,ucbcY2n#2
http://imgur.com/KqEc71J,6bsIFEE,IGr1YS ... ,ucbcY2n#3

The torch itself didn't heat up at all. And I just love the small size and flex neck!! Also the fabric hose cover is great, very flexible. Maybe the best money I've ever spent! I have a gas lens on it with a 7 size cup.
http://imgur.com/KqEc71J,6bsIFEE,IGr1YS ... ,ucbcY2n#1

[Otto Nobedder]

sunpelli,

That's great! Now you have a starting point for a permanent setup. A cover and some simple filtration (pickup screen?), to keep crap out of the water, and allow for the possibility for additional cooling if you go to max amps on heavy sections. An automotive heater core makes a great, cheap heat exchanger should you need one, and with a fair-sized reservoir, a fan may be unneeded.

Be aware if you see freezing temperatures in your shop, the preferred antifreeze is a specific "low-conductivity" antifreeze available at welding shops, BUT, RV antifreeze is an adequate substitute... It's made for plastic and vinyl piping, with no need for "corrosion inhibitors" like automotive antifreeze. It's also less toxic to pets if spilled (propylene glycol, rather than ethylene glycol).

Steve S