Funnel-shaped gas flow checkers?

admin

Please forgive the basic question. I just added a tank of straight CO2 to my MIG welder, and I'd like to get a sense of what flow rate I'm actually using. I have it adjusted what I think is fairly "low", while still avoiding visible problems with the welds. But my basic regulator is for CO2/Argon, not straight CO2. So I don't think I can trust the markings on the gauge. It's just the dial type, not the floating-ball style. I have it set to 15 CFH. I've seen flow checkers that are sort of a funnel-shaped device that you put over the nozzle, facing up, then you flow and read the ball. But I'm having some trouble finding an inexpensive source for them. I think, in part, because I'm not sure what they're normally called (what to search for). At this place, I don't reach the minimum order amount. http://weldingdirect.com/gasflowchecker.htmlBut these seem like a nice way to quickly check the *actual* flow at the nozzle, vs what the regulator "thinks" it will be. Can someone tell me what these are typically called? Are they any good? I tried checking my flow yesterday with something I made (measuring displaced water volume vs time). But I don't think the results were that accurate, I think I added too much restriction to flow. I need to tweak the setup and try again. But my method still only lets me re-evaluate the markings on the regulator, and still isn't useful for checking actual flow "on the fly". Thanks.
Reply:I am a believer.I have 6 of them I bought from www.netwelding.com . It is called the portable flowmeter. Mine cost twice the amount of yours but I am only concerned with argon, and that is all it reads in CFH.  I think the density of argon and co2 is close enough to trust the reading at the nozzle. With the gas saver hoses and the portable flowmeters I have reduced consumption quit a bit. Enough to cover the cost over a 6 month period. You will be shocked at the surge at the beginning of each weld as witnessed by the portable flowmeter.The one you listed is cheap enough, I don't think you will go wrong to try it.And yes, mine are dead on accurate.Last edited by shovelon; 03-25-2012 at 09:30 PM.Reason: oldWeld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:for what its worth, CO2 mol.weight is 44, and argon is 40, mixed at 75/25 it is 41.  They are close enough that you can't really tell any difference in any standard flowmeter.  CO2 is 7% heavier than 75/25Experience is something you get right after you need it
Reply:You can always run a bunch of welds while adjusting the flow until you have it as low as possible without having any contamination, This would work if most of your work is under the same conditions but might not work so well if you are doing a bunch of different things, welding different joint configurations or different positions.
Reply:Thanks guys. The site I linked to has a $50 minimum order, unfortunately. And I don't need that much stuff. I like the unit they're showing, however; the multiple sets of lines for different gasses is nice. I found one on eBay from arc-zoneweldingsupplies, but it's almost $30 shipped. Heck, that's a whole 20 lb fill of CO2  I don't think it could save me (with my usage) a full tank of gas. I will try some more beads, ironmangq, set at different indicated rates. I've tried it down at 10 CFH, and seemed to get decent results. But I need to try some more. And I will take another shot at my homemade flow checking method.
Reply:On your next order, get the meters from arc-zone.com there like $15 or so. I use them and they are a great spot check.
Reply:They are a great device for measuring your gas flow at the torch which is where you need it.I usually set my regulator to 7.5 litres per minute (metric here in Oz) measured at the torch with one of these units.Much below that I start to get gas coverage problems and above it is simply a waste of Argon.I try to use it every morning when I start because of "gauge creep" as I call it where as the bottle goes down the flow of gas through the regulator actually goes up.It doesn't sound right but it's actually what happens.If I don't check for a few days I'll find I'm using 10 litres per minute or more so I'm constantly turning the regulator down over the life of the gas bottle to try and maximise how long the bottle lasts for.Regards Andrew from Oz.