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I looking for some tips since I started school I've never thought of welding with it so I never tried now I have to take a test with backing I did a test run and didn't come out right now I have to do one in horizontal and one in vertical any tips on what to look for oh and it has to be done in 7018 with a 1/4 root opening any advice will be greatly appreciated
Reply:Originally Posted by smc1118 I did a test run and didn't come out right
Reply:One issue I'm having it filling to one side instead of directly in the middle when I did horizontal maybe it was because I was sitting in a chair I'll try standing up
Reply:Well its not open root if your using a backing plate. 2g is easy just kinda do a W motion, 3G is a bitch! Use the biggest heaviest backing plate they will let u and run at 100 amps for the root with a very slight side to side motion so the puddle consumes the sides and the toes tie in. On the root pass I stop right in the middle and let the plate cool so I don't go building stalagtites, some don't tho. Its what ever works best for you. After a few passes i up it to 105 and let it cool between passes. After 20 passes i up it to 115 amps and still let t cool between passes. Main thing is ty to avoid undercut and clean the hell out of the toes with a wire wheel to make sure you don't have any slag left to cause porosity in the bend test.
Reply:Oh another little thing people take for granted to tell ya. The most important part is fit up. Make sure there is no gap between the backing plate and your beveled pieces to let air in and kill your weld. Put 6 heavy tacks on the backing plate because its gonna want to separate when the piece gets hot and starts tryin to fold in
Reply:1/4" root I'd tend to fill in two passes vs trying to weave and fill it in one fell swoop. It's certainly doable in one pass using larger rods or if you are good, but I'd want to concentrate on making sure I burned in the two pieces well, and for that I'd want to run two beads vs just one..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I wanted to as well but my instructors wouldn't let us...so that's just the way we learned it
Reply:I get the feeling this is one of those "I should have known "questions but...Does the backer plate get welded to the root pass and if so How do you remove it after the welding is done?Gizzmo
Reply:Originally Posted by gizzmoI get the feeling this is one of those "I should have known "questions but...Does the backer plate get welded to the root pass and if so How do you remove it after the welding is done?Gizzmo
Reply:Originally Posted by jamesyarbroughThat's not a stupid question. I guess in a real world situation they would leave it. But in a bend test you remove it before the bend test. On 1/4 inch plate you "scarf" it off with a torch that has a curved tip...
Reply:Thank for the advice
Reply:Originally Posted by gizzmoI'd Like to see a video doing that! Sounds like an easy way do do it. Thanks for the answer!Gizzmo
Reply:To me scarfing is a pita. I really hate it. Its hot as heck, there's a crap load of slag, it puts a lot of heat in your coupons and if you get just a hair too deep you gotta scrap the whole thing and start over.
Reply:Originally Posted by Carnes Lake FarmsIts quite easy to do. I use a regular torch tip and keep it at 90* and melt it off. I rarely hit the o2 lever and slowly work the torch from side to side until the backing bar is melted of. It's a slower process but if done right works great. |
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发表于 2021-8-31 22:43:06