Arc beginner - In need of a few pointers please.

[secretsmoker]

Hello there, I have been away from forums for a bit but I have been continuing to weld as regularly as time allows. Having done C&G 1 on MIG, and now passed TIG level 1, I have now started on Arc level 1!

It is still early days as the evening course just started this week. I am pretty familiar now with the basic principles of what I need to do in general to get a pass but, MMA seems to have some particular
peculiarities.

Here are 2 plates I was practicing on, order of runs on the pics is bottom first, top then middle. 2.5mm 6013 electrodes. 1st 2 runs on 80amps, 3rd on 75 if I remember correctly. Plant was a massive old 3 phase Murex oil cooled thing.

It is the beginning of the first run (bottom ones) I am having the most problems with...

From the side...

...Can you see the problem?

I suspect because the steel and electrode are both cold to begin with the penetration is lessened until the heat builds. I tried stirring slightly on the spot which did not help. I then tried arcing up slightly in front of where I wanted to begin then dragging it back to the beginning but that didn't seem to help either.

Would I be in need of more amps for the first run? I found that on the 3rd run I was needing to turn the amps down to get a decent profile. Problem is that on the first run, any more amps seems to result in too flat a profile. Any ideas what I am doing wrong or should I just smuggle my plate to the guy on the oxy acet booth each time I want to begin a new plate and ask him to blast the corner for me?!

I know my travel speed and aim aren't brilliant but i am beginning to make some progress. Used a third of a box of rods in a couple of hours yesterday! Anything else I need to watch out for?

Cheers folks! Sorry about the massive pics, at least you can see what I mean!

 

[secretsmoker]

Feel like I should also point out that the scummy crap all over the surface of the steel is mostly from the filthy rust coloured water it was doused in. All surfaces were shiny and free from mill scale before I did any welding!

 

[shenion]

2.5mm looks a bit small for that size plate, hence the cold starts.

They look good, I'd probably up the amps a bit, use a short arc (smaller rods like a light drag) and move a bit faster. You'll probably get less spatter.

The brand of rod can make a difference, especially on smaller rods. No-name ones can be real hard to get a feel for.

 

[secretsmoker]

Thankyou kind sir! It was my tutor who suggested I start off with the 2.5 mm rods, saying that I would probably pick up the technique more easily. Not sure whether saying this was a test as both sizes are readily available in the cupboard! Now that you mention it, trying the bigger rods does seem like the obvious solution! More amps, shorter arc, faster speed; I shall give this a try first thing next time.

I am really excited to be doing more arc but the nuance required in the technique is truly mind boggling for the beginner once you realise what it actually going on.

Not entirely sure what brand of rods we are using but I get the feeling that they probably will be branded ones as this college doesn't seem to be in the habit of penny pinching on materials. I will try and have a look at the box next time as several people have reported having a favourite brand which 'works' for them over others.

At the moment I am still sticking rods to plate a couple of times before I manage to get the arc started but I am beginning to show signs of improvement.

 

[rich r]

I recommend starting on 2.5mm rods too - anything smaller can be tricky to get the hang of due to the flux/filler ratio and speed you have to move at. Anything bigger and you can get away with poor technique.

Your stringers looks pretty good - just need a a shorter arc and maybe a 5-10 Amps more. As said above, smaller rods often work better when lightly dragged along the surface (with 1.6mm rods it's about the only way you can get anything half decent). Angle the rod slightly so the edge of the flux coating is on the metal, but the rod's core isn't quite touching. You'll find it easier to maintain a 1mm or so arc and also it helps with the stability of movement.

As for rods sticking at the initial strike - cold rods on cold metal stick. Once one or both are hot, it tends not to happen so much. I tend to strike a fresh rod on a bit of scrap metal to get it going, then move to the workpiece, where I know it'll start nicely.

 

[secretsmoker]

I had never even heard of the drag technique before this thread. The tutors at this stage are pretty much leaving us to our own devices but I am finding it quite difficult as I like quite specific advice whilst they are usually in the habit of giving more general tips. This forum is great for getting more focused pro tips. Many thanks once again.

I was quite happy this week that my welds were improving slightly. I am pretty much a beginner at this and I was pushing the electrode like you would with MIG. Watched the tutorial videos on this site and I was away after that. SO much easier doing it the other way!

I plan to try both sizes of rods next week but I will try more amps and the short arc using 2.5mm and try to get my travel speed more consistent.

 

[secretsmoker]

Cheers for the tips folks! No pics for now but even though I was a bit rusty after 6 days not welding, I passed my first test piece! I am quite pleased but also realise that 3 stringers in parallel on a puny plate is the tip of a particularly massive ice burg...

Next test piece is a lap joint then two t pieces in different positions then an open corner. Have to confess my first attempts at a lap joint have not been going well and i am finding it mucch harder than the last TIG course which had the same test pieces.

I am preparing the top plate with a square edge. I am really struggling to find the right angle enough to melt it good and struggling to use travel speed or weave to build it up to the top edge. I guess my problem is just lack of experience so i am not too worried just for now as this is still only level 1.

 

[rich r]

In the majority of cases, there is no need to weave when doing MMA. If the material is much thicker than the rod, you'd run a root pass (ie right in the corner), then brush off the slag and run a couple of capping passes over it to bring the weld up to the same thickness - consolidating the two pieces of metal and the root pass weld into a single piece. Have a look at http://www.mig-welding.co.uk/arc-fillet-joints.htm

 

[secretsmoker]

The video on this site has been helpful along with some youtube stuff. Concentrating so hard, finding a comfy position and trying not to jerk are part of my problem at this stage, correct amps for the job and figuring out arc gap and travel speed are another problem entirely. I will probably try nothing but lap joints tonight and hopefully report back with some pics...

 

[rich r]

You'll probably find (as with a lot of things) that one day you just pick up the electrode holder, clip in a rod and weld an almost perfect joint without thinking about it. The speed and smoothness of movement will come naturally - it just takes practice. Remember that the power doesn't have to be on - you can practice moving the rod over and over until it feels natural. Similarly keeping the arc length right will come with time.

Keep practising - you'll get to a point where you're not having to concentrate so hard. Just like riding a bike

(and then you'll try welding in positions that aren't flat on the bench. That's a whole new set of techniques to learn!)

 

[EAZEE]

Another pointer for is to flare the rods at the start to get some heat in. You should do this on all starts and when producing a re-start also. it helps get it nice and smmmmmmooooooootttttttthhhhh.

 

[secretsmoker]

A few pics from tonight's session. Beginning to get a bit more of a feel now. Restarts are still quite difficult but since I began lighting up before starting a run my welds have greatly improved! Managed to finish a lap joint test piece tonight so several T fillets for tomorrow night is the plan now hopefully.

The weld in the pics was the last of many I layed down tonight. 2.5mm root 85 at Amps then 3.2mm cap at 110 Amps. Possibly could've done with less amps in retrospect and there is a bit of undercutting. Again this is only C&G level 1 so the below constitutes a pass and it doesn't get strength tested.

Rods are ESAB brand as it turns out and the machine was a big ole' Murex oil drum beast again...

Still frustrated that my ripples seem to be quite widely spaced compared to good welds I have seen around the workshop. My consistency is still a bit shaky but I am at least managing to join 2 pieces together now (first attempts were WAY too embarrassing to upload hahah). Working on the neatness a bit more hopefully tomorrow.

 

[rich r]

Looking good. Just keep at it - you'll find you can move more smoothly (and hence get a more even weld) the more you do it. Slightly shorter arc might help with the spatter but it's not too bad. How easily did the slag come off? If you get the amps, arc length and travel speed right, the slag should just peel off on it own, or come off as a single piece if you just prod it at one end. Different brands of rods have quite some bearing on this too - but I've had slag peeling nicely using Aldi 2.5mm rods most of the time.

 

[secretsmoker]

Thanks a lot, it is great to get some feedback. At college they are not too particular about the level 1 welds and spend a lot longer giving critique to the level 2 folks. I do get feedback but sometimes not enough to work out how I could improve!

Beginning to see what people mean about slag that just pings off. The weld in the photo needed a light chipping to get it started, but a lot of the stringers I was doing for practice yesterday were unwrapping themselves before I even picked up the hammer!

I think tonight I will get myself started by preparing 2 or 3 T fillets ready to weld and then try welding continuously on both sides. Hopefully by the third one I might have another test piece, if not I will grind them out (assuming the airlines are working!) and start again. The constant prepping of new bits of steel in-between annoys me slightly when I just want to get on with welding!

 

[EAZEE]

Hi Mate,
Just letting you know that on the C&G 1, only single runs are allowed!!!! However the guy that is teaching you know his stuff as I would do a root and cap also. You're right about your cap though, turn the amps to about 100 or a bit lower as you have pre-heated the test piece with your root run.

 

[secretsmoker]

Back to college again this evening. Last night I was still struggling with pesky horizontal/vertical T fillets!

Reading specs for the 2.5 rods a few places seem to recommend no more than 85-90 amps. My tutor is recommending I try T fillet root runs using 2.5s with more amps to burn it in. Only problem is that when I crank up the amps obviously the electrode burns up more quickly so that I may have to stop/start 3/4 of the way down. Perhaps I am traveling too slowly. My question would be what is the maximum usable ampage with 2.5mm 6013?

Tonight I need to concentrate on my angles more as a couple of times I had started well but slipped too far towards the base plate by the end resulting in the end of the weld being much to wide and not very tall. Most of the time I can see what the problem is but consistency is proving to be much harder to grasp with MMA just doing it 2 nights per week with no welding in between!

Not sure about the single run thing as I had heard that too for lap joints. Our college encourages root/cap. I suppose a skilled hand could probably build up far enough with one run at this thickness but they have never disallowed any of my multi run test pieces. Consulting the book last night I think 2 runs are expected on the T sections but no more than 2.

 

[fixerupper]

As an untrained welder bodger ,I think your welds look great..... Just recently with the rods I can get here in Crete I always/ sometimes end up with slag in the bead not sat on top do you know why ?..jeff...