MIG Test for Work
Posted: Wed Feb 06, 2019 7:13 pm
Hey Ya'll,
I've done some MIG and TIG welding as part of my job in the past, but now I'm trying to get my first job as a full-time fabricator. I went for an interview/weld test yesterday and got some surprises. I thought I'd share in case it helps someone else land a job.
The written test was 9 pages long. Luckily, I studied the weld symbols before I went in and already had calculators loaded on my phone that could handle square root, area conversions, and circle math (on the last two weld tests, the employers encouraged me to use my phone). There were the usual triangle math questions as well as questions about what general settings do you start with on the gauges for an acetylene torch, what general settings do you start with on a MIG welder with .035 wire, as well as questions about how to read and interpret blueprints.
The fun came when it got time for the hands-on weld test. The manager left me with a welder that had no settings chart. If you don't know what to do in that instance, check out Jody's MIG Welding 3 video: http://www.weldingtipsandtricks.com/mig ... ics-3.html. Then when I started to do a test weld, I pressed the trigger and when I let off the trigger, the wire just kept flowing until I pressed the trigger again. I'd never seen that before. There was a switch on the front of the welder that turned this on/off.
The test manager gave me with some metal parts and a blueprint. Luckily, I measured the parts before I did anything and one of the parts he gave me was wrong, so I got that figured out right away before anything got tacked up.
After I welded up the first assembly with hard wire, the manager came back with a roll of flux core wire, dropped it on the table, and told me to weld up the second piece using flux core. Flux core is a different beast and it's not something you want to try for the first time in a live test. Luckily, I've done some flux core welding in the past and knew that it was more difficult to feed smoothly. On my test welds, the wire was sticking and I knew that I had to tighten up the roller tension to get it working. Flux core usually (always?) requires you to switch the leads and run DCEN. In all my test nervousness, I forgot to do that, but my welds came out looking fine. They didn't do a destructive test, so maybe they looked fine, but were structurally weak or maybe they really were fine, I don't know.
The other thing about flux core is that you can run it with shield gas ("dual shield") or without. This being a big shop, their weld machines didn't use the usual tanks that you see on small welders. They were hooked up to a gas line running down the wall. Just something to be aware of if you walk in and find a MIG welder without a tank on it. Again, being someone who has only worked in small shops, I'd never seen this before either.
Every time I apply for a fabrication job, I learn a lot just from the tests. I hope some of this helps you too.
--MATT
I've done some MIG and TIG welding as part of my job in the past, but now I'm trying to get my first job as a full-time fabricator. I went for an interview/weld test yesterday and got some surprises. I thought I'd share in case it helps someone else land a job.
The written test was 9 pages long. Luckily, I studied the weld symbols before I went in and already had calculators loaded on my phone that could handle square root, area conversions, and circle math (on the last two weld tests, the employers encouraged me to use my phone). There were the usual triangle math questions as well as questions about what general settings do you start with on the gauges for an acetylene torch, what general settings do you start with on a MIG welder with .035 wire, as well as questions about how to read and interpret blueprints.
The fun came when it got time for the hands-on weld test. The manager left me with a welder that had no settings chart. If you don't know what to do in that instance, check out Jody's MIG Welding 3 video: http://www.weldingtipsandtricks.com/mig ... ics-3.html. Then when I started to do a test weld, I pressed the trigger and when I let off the trigger, the wire just kept flowing until I pressed the trigger again. I'd never seen that before. There was a switch on the front of the welder that turned this on/off.
The test manager gave me with some metal parts and a blueprint. Luckily, I measured the parts before I did anything and one of the parts he gave me was wrong, so I got that figured out right away before anything got tacked up.
After I welded up the first assembly with hard wire, the manager came back with a roll of flux core wire, dropped it on the table, and told me to weld up the second piece using flux core. Flux core is a different beast and it's not something you want to try for the first time in a live test. Luckily, I've done some flux core welding in the past and knew that it was more difficult to feed smoothly. On my test welds, the wire was sticking and I knew that I had to tighten up the roller tension to get it working. Flux core usually (always?) requires you to switch the leads and run DCEN. In all my test nervousness, I forgot to do that, but my welds came out looking fine. They didn't do a destructive test, so maybe they looked fine, but were structurally weak or maybe they really were fine, I don't know.
The other thing about flux core is that you can run it with shield gas ("dual shield") or without. This being a big shop, their weld machines didn't use the usual tanks that you see on small welders. They were hooked up to a gas line running down the wall. Just something to be aware of if you walk in and find a MIG welder without a tank on it. Again, being someone who has only worked in small shops, I'd never seen this before either.
Every time I apply for a fabrication job, I learn a lot just from the tests. I hope some of this helps you too.
--MATT