Need Advice on MIG Cert. Test

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In the very near future I will be scheduling a MIG Cert test.  It will be a lap joint on 1/2" plate.  Im well aware that this is a very simple weld but the thickest material I weld on at work is usually quarter plate and I obviously want to pass so I thought I would pick the brain of some more experienced guys and/or guys who have taken that particular test before.  Info such as how many passes I need to make and wether or not I need to bevel would be great.  Any help is appreciated.  Thanks.Last edited by werewolf8886; 02-28-2012 at 09:05 PM.
Reply:Wire, gas, type of welding process, size of wire, which test etcUA local 32Team weld-coolTeam miller elite tack upMiller pro-staff
Reply:Position? 1F, 2F or 4F I'd just run stringers, maybe 1, then 2, then 3, and then 4 (total 10 passes). For 3F, a weave uphill, maybe 4 passes? Depends on how much fill you need. You'll probably need preheat and run hotWhatever you do, GET COMFORTABLE. 90% of MIG welding is about "position". Get creative with fabricating supports using the visegrips, scrap bars (they call them "drops" not scrap), etc ... Watch the molten metal, not the arcLast edited by wirehead; 02-28-2012 at 09:42 PM.XMT304 (school)SP125+ (home)HF 4x6 BandsawGood judgement comes from experience and much of that comes from bad judgement.
Reply:flat, 035 wire, C25.
Reply:Get some scrap and run a few plates.  Its the best way to know for sure.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Don't even think about short-circuiting it, get your volts up around 26-28V and tune in a nice spray.  Easiest test you will ever take.Have we all gone mad?
Reply:My GMAW cert under the AWS D1.1 is from 1/8" to 3/4" plate using short circuiting, so 1/2" using OP's parameters must be possible. I've never done spray (C25 doesn't support it, need more argon than 75% but 100% argon works like s**t!)Last edited by wirehead; 02-29-2012 at 01:04 PM.XMT304 (school)SP125+ (home)HF 4x6 BandsawGood judgement comes from experience and much of that comes from bad judgement.
Reply:Just wanted to add one more thing before your "mission critical" weld. Check your equipment BEFORE you start. Few things are more frustrating than watching your nearly complete weld go all to hell in air. Happened to me on my first 3G attempt for certification - 3 inches to go on the cover pass, doing good, and whoops! Certs were for xray so had to try again the next day. Second night same thing, 3 inches to go and then poof wire burns back - spool is empty.  Oh well, live and learn. Third attempt was a charm.There's a lesson here. One I won't forget anyway.Good luck!Last edited by wirehead; 02-29-2012 at 10:30 PM.XMT304 (school)SP125+ (home)HF 4x6 BandsawGood judgement comes from experience and much of that comes from bad judgement.
Reply:Short Circuit GMAW is not prequalified under D1.1.  If that is the process you are using then the Welding Procedure Specification (WPS) will have very specific joint dimensions and edge preparation details, as well as voltage and wire feed speed ranges (because the specific joint and process details, and complete test plate would need to pass visual, UT or RT testing, and a destructive testing).  Do you have access to that paperwork?  can you ask for it ahead of time?  You mention its a lap joint using 1/2 plate.  Pretty thick stuff to be using GMAW-S on.  If you could verify this it would help us help you.Sent from my DROID3 using TapatalkJay DavisAWS-CWIC-60 Specialty Welding ContractorLoving husband, and father of two boys (
Reply:I will gather that info tomorrow evening and get back to you asap.  Thanks.