Mig Progress, all comments welcome
 

Well as the other thread titled Murex mig be quick seems to be playing hide and seek I'l post some progress here.

The difference between .6 and .8 was like night and day, so much easier

I started on the small piece and finished on the bigger one, by time I'd got to the bigger one I found the push/pull techniques coming into play, I found the push worked better on the internal joints and the pull was better on the flats.

I put a small chamfer on the edges of all the bits on the last piece which I think helped as well

I'm still not convinced I've got enough penetration, but as I'm typing I'm thinking I could cross section through the welds and post some pics, hmm later maybe.

Also the beads still seem a bit large and proud, or maybe that's just me.

Anyway criticisms, comments and advice pleeeeeeeeeeeeease :)





Ps. The guy I bought the welder from had been running the .8 wire in the .6 side of the wheel!

Do you have an adjustable wire feed as in a dial on your machine or is it a flick switch all or nothing option?

Fully adjustable from 1-10 Phil.

Edit: Was running about 4.5 on the above using .6 but before couldnt go above 2 using .8

Welds look good but either turn the heat up a little or the feed down maybe 0.3-0.4 between marks on the dial.
All the welds you should be pushing the heat so that you prewarm the material in front of the arc pool then fill with wire which gives better penetration, if you pull the torch/arc over the cold material you get a cold weld and it lays on the top which looking again is what you might have done.
The problem with doing short welds to practise with is by the time you've got your eye in you have to stop. MIG welding 1.6mm material is a balance between penetration and not blowing through, I run my MIG at 180 amps with 0.8 wire with the speed around 4.5-5.0 Yes according to the books it's too hot but it means the first arc is hot to get the root in. If you have tube spare put two lengths side by side and do a long run up the middle,when you can get a smooth bead that's not too high then try again on the short runs.

Dont listen to phil with his .8 wire and 180 amps bruce. He has had years at it so can get away with it. Stick with the .6 , there is nothing wrong with what you are doing for first attempts just keep practising and as phil said play with the amps/wire feed. One thing not touched on here is getting yourself comfy, I always try to position myself so my elbow is resting on somethng which helps steady the hand, Sounds silly but helps.

bob

who stole the mig thread. :)

Bob is right in what he says about being comfortable while welding, the best way to do this is to put a pad on your bench and write 1-2 long sentence's in your best hand writing. If your getting eye strain,cramp,back ache then guess what your work bench is too low. My wishbone and upright welding bench is 150mm lower than my nipples sounds silly try it, means my elbow falls on the bench with my hand on the side of my head and I'm comfortably slouched. When you do 6 hours working on the same jig for 6 months there is a few little tricks you learn to save your self.

lol, Cheers Bob, will def be sticking with the .6 as I found it a lot easier than when using the .8. Like you said before I have no doubt experience will let you use the .8 to good effect but I found the wire feed so sensitive with it it was hard to get to to where it felt right.

I'm assuming your referring to my wandering lines when you say about leaning on something? I'm actually finding it hard to see the metal behind the arc sometimes and finding I've wandered off line.

Phil, what you've said about using a longer length to get the settings right makes perfect sense. In my 'wisdom' I purposefully chose the short weld lengths to practice on as I was struggling with them, I think in hindsight I was just making things harder for myself, oops!

I've got just under 2m left of the box section, I was going to use it to make a wall bracket for my butler sink to go in the shed but that can wait. I'l try some long lengths, get happy with the settings and make another tree.

Thank you all :)

If you are right handed you need to work right to left with the torch at about 60' so that you can see the wire going in to the edges of the material being welded. You would not put a jig saw blade in back wards and drag it down the job and hope you hit the line some where so why do it while welding?


Next week we'll cover over head stitch welding and how to avoid getting splatter bouncing down the inside of your overalls and burning the crack of your arse....

Phil, my bench is quite high 990mm if I'm stood upright its only about an inch below my elbow (I'm a shortarse) and I had the bar in the vice so it did feel relatively comfortable to stand and weld. I have a dicky disc in my back so leaning forward just slighty even just for a few minutes can get very uncomfortable.

I said behind the arc which was a bad description and misleading, I am right handed and generally was working right to left with the torch slightly angled so I had a good line of sight view of the arc and joint but found once the arc was struck the metal was just a dark/black background. I'm using a cheapy auto helmet.

Will try all the suggestions hopefully tomorrow if I get chance to get back out there.

Always push MIG (MAGS), the only weld you pull is ARC (MMA).

Are you colour blind at all.? (I am) If not then either your shield is either too dark or you need to run a bit of french chalk down the join before you weld it ( I do sometimes on long sheet metal runs ;) ) highlights the joint loads as you go.

Never thought of eyesight, I don't believe I'm colour blind, at least I wasn't last time I got checked, however I'm at least 6/7 years overdue for an eye test, oops, got all the kids tested up to date but not got round to doing mine. I did have prescription glasses for close up work but it was only minor, they broke years ago and I haven't struggled without them to much so just not got round to getting a retest. I should really get that done anyway.

I suspect the mask a little bit, but apart from that it seems to be fine and I don't remember having the same problem when using the tig, I can make out the shadows of the corner radius sometimes but not always, I was also wondering if its my lighting in the shed, I have florescent strips down the centre which are behind be when at the bench so I'm working in the shadow. I have got wiring in the walls for dedicated bench task lights but not found any 'on a budget' style yet;)

I assume the chalk is ok to us, ie doesn't introduce contaminants into the weld? I think that might be my answer :)

TY Dualist

The first thing I taught my apprentices in welding class is to get in an absolute comfortable position for the weld even if it mean you have to sit down - do a test "dry" run to see if you have 100% control and always stays your welding hand with elbow or use other hand as a support to rest the weld hand on.

Will look at how I was standing and try and move things around a bit to improve access/control, no play to day as little one off sick :(

Some more piccies for you to amuse yourselves with.

Trying to take in all the advice above, I tried sitting down but it didn't feel comfortable, like I didn't have enough control on the torch, felt much better standing up. I wanted to do some more longer runs but didn't have as much box section left as I thought.

Most of these are pushing which definitely feels better and helps with the problem I'm having seeing the join which didn't seem so bad today.

I think some of my problem is down to technique and travel speed which I was trying to experiment with today. I did also try upping the power a notch but then the wire started balling so upped the wire speed a little which seemed to put me back to laying what looked like a flat slug on the joint.

Overall I think some are slightly better and I felt like I was getting a bit more control over the puddle and bead so just got to find lots of thing to weld and practice as much as possible.

I keep reading about it sounding like bacon frying! Well I must be cooking my bacon all wrong as it's never come close lol, what I did get was a nice even buzzy sound, not popping or machine gunning so I think settings wise it probably not too far off.

I find a good breathing cycle helps, much like shooting a rifle. A good few deep breaths to get your blood well oxygenated, then on the last deep breath exhale slowly then hold your breath half way through the exhale. This gives your body between 7-10 seconds of pure stillness. With practice you can get longer depending on how many tabs you smoke:D Perfect for getting those tricky welds in the corners without wobbling, especially if you can get your body "jammed" into a good position ie both hands on torch, both elbows on bench and waist tight against bench.

Breathe
Brace
Stance
Vision
Rate
Power
Penetration
I've just read this thread again and I'm sat here in fits of laughter, all we need now is a few sniper riffles and a pack of cards and we'll all be nailing the ace at 1000 yards next week. Sorry I'll keep it to my self now.

Thanks phil i feel ready to take the missus to bed now:eek: :D :eek:

shh120m, Yep, I think another part of my problem is I want it to be perfect too much so getting tense when its not going right.

Talonmotorsport, you know there are certain things that should happen in the bedroom and stay in the bedroom (Happy Smilie)

shh120m, fill your boots mate (Happy Smilie)

Why do smilies count as images? argggh

I take it the welds are that bad you dont want to mention them then? (embarrassed Smilie)

Certainly look hot enough, but maybe the wire feed is a little fast. Will the power go up any further? Are you pushing as opposed to pulling the pool?

I tend to find if i put the power to the max, and start the pool on the sde of the tube not the open ended one then you can get the pool penetrating. As soon as its about to blow through, hop over to the open ended tube then straight back again and work along like that. I find it helps to "suck" the filler in as opossed to sitting ontop if that makes sense

Mostly pushing, found it a lot easier, I think I get what yo mean about focusing on the thicker piece but don't get the sucky bit :eek:

Welds are fine as they are curtainly not bird poo examples either wind wire feed back a little or up the rate of weld ie go alittle faster, this is MIG welding and the welds will be proud of the surface no matter what.

I am going out a limb here bruce and reckon you might have a crap helmet/ sight glass. Your welds in the corners are good but the stuff on the flats is all over the place. I think your good in the corners because you have two flats at 90 degrees to guide you. Try a lighter glass and weld between two scribe lines as a guide and see how you get on.

Bob

Bob, this is the helmet I'm using, I'm pretty sure I've got travel rate and consistency issues but I'm not sure the helmets helping as I'm still struggling with seeing the joint, will give it a try with scribing and chalking as dualist mentioned when I get set up for a next play

Cant do much more now as I've run out of tube, have to go scrounging round the industrial estates :cool:

In the meantime I'l get my eyes tested, I should get that up to date regardless.

http://www.weldairsupplies.co.uk/swp...9-13-152-p.asp

Those speedy glass things are not brilliant if you have light coming in from behind. I dont get on with them.

Bob

You think Its worth a try without the main lights on? The main ceiling lights running down the centre?

I have a £2.99 Ikea (other lamps are available) desk lap above my bench which balances out the 8 strip lights behind me, just be sure that you don't have the filter set too senseative or it goes dark before you've even started.

DoS, do a destructive test or two. Weld a piece of box to the longer tube with just one fillet seam and then flex it until it breaks off.

Thanks Albert, yes I think I need to do some testing like you suggest, also if I can find a small enough amount I'l get some etching solution and do some slicing and checking.

I have a couple of little hobby lights which I've tried and also without the lighting behind me, neither made much difference so hopefully chalking and scribing will help.

I am not knocking the testing but really once you have the hang of it you know in an instant if the weld is any good or not. You should be in a position by the time you start welding the chassis to know if there is penetration or not and that just comes with heaps of practice. You need clear vision of whats going on and plenty of time with the torch in your hand. Judging your first attempts at mig you wont be long:) Its also a big mistake to just roll stuff around on the bench, as soon as you are happy with that start on some positional stuff. The learning curve begins again with vertical, horizontal and overhead., all of which you will need at some point in the build.:eek:

Bob

I had to play with the settings on the mask to get it right. Just a tiny bit too low or high and it's really difficult to see the weld pool.

Gaz, I'm ok seeing the pool but been having a little trouble seeing the joint lines so am tending to wander off line, going to try the chalk/scribe methods suggested.

This is what make Mig dangerous in the hands of novices and even professionals. During my tenure as an apprentice boilermaker instructor I could not drive this fact home enough to the appies and a stunt I usually did was to perform a beautiful fillet weld knowingly it had not penetrated well which impressed them big time. Big were their surprise when I took a hammer and with a fast blow just knock the weld clean off:eek:
This is the very reason as a b/maker I built and welded my own chassis. Just not trust anyone with Mig.... To prove my point I attach a picture of a failed Mig weld on suspension bracket from a factory built Westfield :eek:
Lesson from this, not all nice looking Mig welds are good welds.;)

Looking at your sample pictures my advice would be that you concentrate on your speed of weld - try to keep it constant because the width of your welds shows uneven speeds. Get this right the rest will come together soon. BTW, better to push Mig rather than pulling it. Doing so you can see where you are welding and watch the pool and usually this result in "flatter" welds as well.