My venture into welding

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Well, I've wanted to learn how to weld for quite a while, but I never really knew how to go about it. Eventually I heard about this place called TechShop that had classes and equipment available for use, so I decided that was a good way to get into it. I wanted to make this thread as a way to keep track of my progress and to get some feedback from more experienced welders, so that I can improve.First I took a basic use class on MIG welders, because the TIG class didn't fit into my schedule. I only got to lay down a few beads and here are the results:A few weeks later, they had a TIG basic use class that fit into my schedule, so I took that. TIG is what I had really been interested in learning all along. Here is the first TIG bead with filler rod that I laid down:I believe this was 16Ga. steel w/ Er70s .045 filler rod @ about 70 amps. Techshop uses Lincoln Precision Tig 225 machines. It has worked great so far, but it was getting pretty close to the amperage limit on some 1/4" aluminum plate. Since taking that class, I've started to buy some equipment and I've gotten a few more practice sessions in, but I think I have about 3-5 hours of actual welding in at this point. I'm still making all kinds of mistakes and learning from them as I go, but sometimes it's hard to recognize why I'm having issues still, especially on the aluminum. Here are some shots of my practice in chronological order:1/2" mild steel plate w/ no filler. I'm not sure on the settings I used here. I had this 1/2" stock lying around from an old machining project. The short little "worm" is my first attempt at adding filler rod since the TIG class.1/2" mild steel again. Most are no filler, but the two short beads at the top and the one at the bottom did use filler. I believe I was using 3/32" ER308L filler rod here. I made this a lot harder on myself in the beginning by using 3/32" stainless rod on 1/2" mild steel with a 1/16" tungsten... Lol. Everyone else had ruined the "community" 3/32" tungsten, so I had no choice there, but this is why I started buying my own consumables. 1/2" mild steel, 3/32" ER308L filler rod, Not sure on machine settings here. I tried to do a fillet weld there and that didn't go so well. Lol. I've since bought some ER70s6 filler rod to use on mild steel. Then I decided I wanted to try some aluminum, because a lot of the welding I plan on doing will be automotive related and there is a lot of aluminum involved in intake systems. 1/8" aluminum (not sure of specific alloy), 1/16" ER5356 filler rod, between 100-120 amps, I had the machine set more towards cleaning vs penetration, no pulse, about 15-17CFH. First I laid down some beads with no filler to get the machine set where I was happy and then laid down beads with filler over those. I felt as though the aluminum went much better than my attempts with the mild steel. However, aluminum does require a lot more attention because of how quickly the part heats up. Thanks for reading and I appreciate any feedback you guys can give!
Reply:Hello and welcome.Ditch the 1/2" plate. It's way too thick to really learn on. It will give you a false sense of accomplishment since the thick material can soak up heat and make it look like you know what you are doing. I'd suggest working with 14 ga to 1/8" stock instead. It's thin enough that you will need to be able to control your heat, but thick enough you won't simply blow holes in the material.Your 1/8" alum, your amps are too low. You need to be up around 150 amps or more. Alum will also often give guys a false sense they can weld when they can't. Most guys try to run with the amps way too low. whne they do this one of two things can happen. 1st you simply dump filler on a cold plate because they melt the filler with the arc and can't get a puddle to form on the base material. Beads look "good" to someone who doesn't know what to look for, but the welds are junk. 2nd thing is if the manage to get a puddle going, they have to sit and wait forever for the piece to heat up enough for it to form. Alum doesn't take excess heat well. Many alloys loose all their strength if heated to fairly low temps, sometimes as low as 350 deg. When you heat up the whole piece, you end up with a huge "soft" area around the weld. the other problem is often as soon as the material is ready to form a puddle, a very large section is ready to go all at once. This makes control almost impossible and often the bottom drops out of the weld making a mess.With alum you need to hit it hot and fast. You need to get the area of the weld hot so fast the material can't bleed off heat fast enough and the puddle forms almost instantly. As soon as this happens, you need too add filler and move quickly, backing down the amps as you go and the piece heats up. The idea is you want to outrun the additional heat input. It seems counter intuitive, but more amps faster puts less heat into the piece than running low amps slower.I'm guessing the piece was pretty hot when you did the alum welds. I see a few at the top that look like they were done on cold material, but the vast majority have that soft grainy look that is an indication that the weld was too hot. Knowing your amps it's pretty easy to spot the issue.To do a good job on alum requires that you have heat control down very well. I find it easier to have students learn the basics 1st on steel that is much more forgiving, until they have the basics down to a point that they make heat adjustment and add filler instinctively. Not all people agree with this method however, but I find most students are less frustrated if they lean steel 1st and then go to alum instead of floundering around almost aimlessly with alum until things eventually start to click.I did this basic tig post a while back for someone else. Rather than retype all of it this evening, I'll simply copy paste it. It's the basics of how we teach tig at the tech school night program. Originally Posted by DSWI've done so many  "how to tig" threads here I've lost count... I should probably start tagging them with "new tig thread" or something like that to make them easier to find.1st go on line to Miller and download their tig handbook as well as the manual for your machine. Read thru them and they will answer most of your basic questions on this. http://www.millerwelds.com/resources/TIGhandbook/As suggested, get some 1/8" steel  ( we use 3" wide 6" long pieces) and grind/sand off the mill scale, both sides preferably. If the steel is oily, you'll also need to wipe it down with acetone ( do not use brake cleaner!) You can skip the grinding if you buy cold rolled rather than hot rolled, but CR is more money. It's usually cheaper to grind. Note a wire wheel will not remove rust or mill scale, only polish it. You need to grind sand to prep.Grind your 3/32" tungsten to a pencil point and set the machine at roughly 125 amps on DC, argon at about 15-20 cfh. Extend the tungsten out of the cup about 3/8" roughly. This will let you see the arc better.1st drill I usually have students do is to just run beads with no filler on flat plate. Try and get comfortable and set up so you can maintain a consistent arc length and travel speed across the piece. You will be using the pedal to manipulate the amps in this drill. As you run the beads, play with the pedal to get a feel on what happens as you depress the pedal. Make the puddle smaller and larger at will. Remember the plate will heat up and if you don't keep cooling it down, it will act like you are upping the amps. I tell students the pieces are cool enough when you can handle them with your bare hands. A quench bucket and several pieces to work with will allow you to keep practicing without having to wait all day for coupons to cool between beads,Next reset the amps to say 90-95 and floor the pedal. In this drill you will now vary either the distance you have the tungsten from the work, or your travel speed ( drill #3 is to vary the one you didn't do in this drill) Get a feel how these changes affect the arc and puddle. Don't worry too much about these right now, the idea is mostly to get you to understand that varying these will change and effect the puddle. For most of the rest of the drills, you'll want to try and maintain as consistent travel speed and arc length as possible and just change your amps with the pedal.After these drills, say maybe an hour of "play time", try to run a bead by adding filler. 1/16" filler is a good size to work with. I usually suggest the students start with a lay wire method where they keep the filler in contact with the plate, and bring the puddle to the filler. Remember you melt the filler with the puddle, not the arc. You can slide the filler along the plate and into and out of the puddle as needed. If your amps are on the low side, some times the filler rod tends to be "sticky" and want to stick to the plate using this method though. Add a few more amps with the pedal if this is the issue. You can also "tap" the filler in like a drum stick or "stab" the filler at the puddle. I usually don't suggest new students stab the filler at the beginning as they usually will constantly hit the tungsten and foul it. get used to grinding your tungsten and get in the habit of stopping to regrind as soon as you foul the tungsten.You also will want to practice feeding filler with your left hand ( assuming you are right handed). Get yourself a length of filler rod, and practice feeding it thru your hand while wearing your tig glove when you are watching tv to help develop the muscle memory for doing this.Once you can run consistent beads the full 6" length of the plate, try overlapping the previous bead by 50%. Once you can consistently do these, you can move on to lap joints, followed by T joints, outside corners, and finally but joints in that order.Then you go back to the beginning for horizontal joints and start the whole process all over again with beads on flat plate... Then the same thing for vertical followed by overhead. After all of this, you can move to thinner  material and start all over again with say 1/16" and then finally start on round tube.Post up picts of your practice pieces along with your settings etc and we'll help you with this.One other thing. Because tig allows you the most control over the weld, it means that there are a lot of things you will have to manage all at once and keep the same to get good results. Best way to learn is to take a class so that someone can watch as you weld and pick up on many of these small changes that you are not aware of. There's only so much that can be done with picts. It's much easier to pick out a lot of this stuff if someone is watching you though.Good luck.
Reply:^^This guy will help you out more than you can imagine! He needs to write a book or do some personal classes!If you need more help look through my old threads for a lot of help. Doug has helped me so much. He is a great teacher.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Thanks, I appreciate the help