Where's my argon going?

[Hobbyist]

I'm a tig newbie just getting started with my first welder. It's a dynasty 200, and I got a 125cf cylinder with it. I have been using a flow anywhere from 10-20 cfh. And I don't think my total flow time could be more than 30-45 minutes. I haven't timed it, but I can't imagine it's more than that. Tallying up everything I've welded, it totals about 80 inches of weld. I know I'm slow, but I don't think I'm moving slower than 2" per minute.

So the way I figure it, that should be 5-15 cf used. But the pressure on my cylinder has fallen from 2200 to 1600, which I figure is about 35cf.

So do I:
1. have a leak
2. not know how to figure this
or
3. have no sense of the passage of time when I'm welding?

[HAWK]

Hobbyist,

I THINK EVERYTHING IS FINE. Be sure to figure post flow times. You can adjust it down to save gas. A 10 second post flow is sufficient for most hobby work. 80" of weld requires a good amount of gas if you are starting and stopping a lot.

You can check for leaks by brushing a soapy water solution on your regulator to tank connection, hose to regulator, hose to contactor, torch to fron panel. If you have a small leak the tank to regulator is the likely culprit. Sometimes even a tight connection will seep when the brass threads get old and nicked.

You can also pull the torch handle back and check the thread connection for the gas line into the torch. I have had it loosen up over time.

[HAWK]

Hobbyist,

When you get busing welding time passes unknowingly. You have probably welded more than you think. Time flies when you are having fun. So does argon.

[Hobbyist]

Hawk,

I'm using the default post flow on the 200dx, must be something around 10sec. I know that accounts for a fair bit of my gas use. Especially at first I was starting and stopping a lot. Lately I'm not stopping as often, and even getting the fan to come on regularly. But another thing that uses the gas is when I tack things. I usually move on to the next tack before the postflow timer is done, but that's still gas that is used with no weld produced.

I imagine it's normal that the gas between the regulator and the solenoid bleeds off between use. I always shut off the gas at the cylinder when I'm done, but don't usually relieve the pressure at the welder. But it's always gone when I come back. Probably the solenoid valve isn't that tight.

It would be cool if the welder had cummulative timers on the contactor and gas solenoid so you could see how much you have welded and how much gas you've used. I'm sure it would be trivial to do on the dynasty with just a small software change. The only hard part would be figuring out how to work that functionality into the keypad.

Of course once you start down the road of making the welder provide useful information, there's a lot more they could do: duty cycle, welder temp, max current. Just the usual problem of making the additional info available without making things too complicated for the new or uninterested user.

Well, I seem to have gotten off my original topic

I'll have to try to keep better track of my welding time from now on.

[Steved]

I thought that I was having the same problem when welding with a 80cu foot tank, it seemed to go by real fast (one weekend of practice) and refilling it was hurting my pocket book. ALmost quit tigging for cost reasons.

After a bit of research I found out that it was price gouging by Liquid Air. They wanted $80 (CDN) to fill the 80 cu foot tank. (I own the tank)

After looking around I ended up leasing a 330 cu foot tank from AirGas for $50/year and they charge me $78 to fill that tank. Now I have LOTS of gas!!!!

On a some what related note, Liquid Air was at least 30-50% higher on all other products than AirGas. (electrodes, rod, etc)

AirGas staff friendly, Liquid Air not so nice (although they did love taking my money) Its pays to 'let you fingers do the walking'

I would get the bigger tank if you have no leaks. In my experience it is WAY more cost effective.

[Glenn B]

Yes it is always more cost effective to buy your sheilding gas in larger cylinders, On the other end it takes the same amount of time and effort to fill the small dinky 20 cft R cylinders as it does to fill the large 300 cft T cyls.
Vent out contents,evacuate with vaccum,fill,leak check etc. so a greater part of the cost on the smaller cyls is handling & labor and not as much the gas in the cyl. The only part that sucks about the large ones is the bite in the wallet that one weekend you forgot tto shut the valve on the cylinder. Ouch a 80.00 oops.
Ps: did you ask for a better deal on your gas? most places charge list unless you have a shop or ask for a better deal. Why give away the farm when customer dosen't ask for a break. More profit on dealers end.

[Steved]

Actually I was quite upset with the prices at Liquid Air but still gave them them the opportunity to change their prices to match AirGas. The did not budge or even care that AirGas was less expensive right across the board.

Agreed that the labour involved when filling cylinders is similar and I think this was the point that you were attempting to make but Liquid Air wanted about $100 more to fill the same sized cylinder and $25 more for the lease. (This was after I mentioned the AirGas price)

There aluminum and SS filler rods were FOUR times more expensive than AirGas, gas cups and electrodes 2 times more expensive, Dynasty 200DX price quote $800 more...I could go on. Perhaps if you are a big player they are competitive but not in my case.

Enough of my rant. I guess the point is...shop around and don't shop at Liquid Air.

[Glenn B]

Yes that sounds like Leeky Air to me. They don't care much about Joe C Public. Just want the big guys. I'll let them dig their own holes. Then they can jump in. I won't lose any sleep over it.

[lramberson]

The famous: "Cost of doing business line from the big guy". No The cost of research and loss to the competitor.. Good job and thanks for the heads up. I will shop around... I am the small guy and own all my own cylinders, I hate paying for rental, & am not able to buy the larger units, oh well.. Sticking to my small.

[Wheels]

Hobbyist
I would still give the soapy water test to your connections. My Dynasty had an internal leak at the gas valve. Using the normal precautions and a snug with an 11/16th wrench and my leak was cured.

Mike

[Canuck]

I have not had good luck from Air Liqude also they seem to favor the big guys not us small guys. I also know that many companys that used Air Liqude have switched to BOC for better service. With that price from airgas I wish there was one around here!
Happy welding.

[Hobbyist]

Originally posted by Wheels
Hobbyist
I would still give the soapy water test to your connections. My Dynasty had an internal leak at the gas valve. Using the normal precautions and a snug with an 11/16th wrench and my leak was cured.

Mike

When you say an internal leak, do you mean you opened the case to find and fix it?

[Wheels]

Yes ,my leak was a loose fitting on the gas valve. I made sure ,first of all, the connections were not the cause of the problem. I made sure the gas was not leaking from the torch as I thought the valve might be stuck. I changed the regulator out with one that I knew didn`t leak, but I still lost the gauge pressure in a matter of seconds. I then let the machine set unplugged for a day to be sure it was (dead)before opening the case!
I hope this is not your problem, as it drove me crazy for a while, but it was a simple to deal with once the problem was found. You might take the machine back to your dealer if you don`t feel safe doing it yourself.

Hope this helped
Mike

[Hobbyist]

I found there is in fact a small leak between the cylinder and regulator. I didn't detect any other leaks an/around the regulator or where the hose goes into the welder.

How tight should the regulator be screwed onto the cylinder?

[HAWK]

A 15" "Crescent" wrench should do the trick. Sometimes the threads are worn and there will be a slow leak. Good luck.