New to welding - any tips for consistent gas flow please..

[kelvinjouhar]

I bought a Thermal Arc 181i a few months ago, although I have not actually started to use it yet - I have been working on some other projects, but very soon I am going to start laying down my first ever beads !! Before I start, I have been getting familiar with the machine, feeding the wire, learning how to untangle a massive birds-nest because I let go of the end of the wire by mistake and trying to achieve a gas flow rate of 10-12 litres/minute - I have one of the gadgets with the little ball in it to gauge the flow.

Ok - so I turned on my gas bottle (Argoshield lite from BOC) and I turned the regulator and after a few tries I can get a consistent 10-12 lpm.... but the regulator is VERY sensitive.... Should I be cracking the tap on the bottle wide open to get the full 200+ pressure and then using the regulator to get 10-12 lpm.... or maybe open the tap a little less to get a lower pressure....?

My concern is getting the right pressure every time I weld.... Is it a case of trial and error (with the wire feed OFF) using the ball-tube gadget to get 10-12 lpm each time before I start to weld ? I am sure these questions are trivial to more experienced people, but I am keen to start off on the right foot so, any tips would be most welcome. Thanks !!

Regards.

 

[BrokenBiker]

I always open the tap fully, not sure if this is right but works for me. that is why you have a regulator. to regulate the pressure down from 200 bar to what you need

 

[pedrobedro]

Your flow meter should be on the end of your regulator on your cylinder. Open the cylinder valve fully, turn the regulator to about 20lpm then regulate that down with your flow meter to whatever you want.

 

[waddycall]

The cylinder valve should be open fully. Adjust the gas flow using the regulator. The regulator should automatically adjust the outlet pressure and maintain it at a consistent pressure and therefore flow rate. It works by balancing a diaphragm against spring pressure which is set by the adjusting knob. When you're finished welding just close the cylinder valve and leave the regulator alone although I believe in theory you're meant to slacken regulators off when not in use. Next time you fire it up you should have the same flow rate.

 

[waddycall]

Sorry should have mentioned that the high pressure (200 bar) is your contents gauge. 200 bar (dependant on gas supplier) is full and 0 bar is empty. The regulators job is to maintain a consistent outlet pressure as the cylinder pressure drops as the gas gets used up. Without the cylinder valve open you won't get a true reading of how much gas you've got left.

 

[kelvinjouhar]

OK - I should have been more specific about the flow gadget that I have - it is just one of the ones that you hold against the end of the torch... I hadn't realised that can get one to attach to the regulator... so effectively you then have two means of regulating the flow, and you can monitor it constantly. I think I will invest in one of those. Thanks for all replies.

 

[the snooper]

if you are welding indoors with no draughts you will only need 10 lpm at most and it isn't one of those things that has to be totally accurate

 

[kelvinjouhar]

Right - I took the plunge and set the machine up and these are my first 2 attempts... The one on the right has slightly higher settings than the one on the left. Any comments will be welcomed. Regards

 

[octo0072000]

you need a bit more power
first one looks a bit cold moving to quick second one better but still tall needs more amps by the look of it but a lot better than some as first attemps