Resume/reatart with new electrode

[martinr]

I've been getting slag trapped in pockets or even as a quarter inch long channel after resuming with a new electrode (laying a capping weave in the vertical up position). (E6013 electrodes) I realise that the problem is down to not getting enough heat into the workpiece before resuming, moving too quickly immediately after resuming or having too wide a weave. (Obviously, I clean the slag and wire brush/grind the end of the previous run before resuming.)

I've found the literature not too helpful eg Page 136 at


http://books.google.co.uk/books?id=zeRiW7en7HAC&lpg=PA70&ots=fQsfkaEfVm&dq=electrode%20weld%20resume%20OR%20restart&pg=PA136#v=onepage&q=electrode%20weld%20resume%20OR%20restart&f=false

This seems a bit impracticable and doesn't help with a weave cover pass.

Even the Lincoln Electric books don't offer much guidance.

So I'd appreciate any tips, advice and warnings concerning how best to restart/resume both the stringer bead and the weave pass and whether it depends on the electrode type and welding position.

Many thanks, once again

Martin

 

[dai]

start ontop of the previous weld then grind flat later
or grind a ramp on the end of the last run to get the heat up before you get to the joint

 

[martinr]

start ontop of the previous weld then grind flat later
or grind a ramp on the end of the last run to get the heat up before you get to the joint

So forget this stuff about striking the arc ahead of the weld and moving back to resume or using a long arc to heat it up before depositing fresh metal?

Martin

 

[Tigman]

There is another thread on here with some good tips , what size rod and what amps are you using , chip the slag off then wire brush but start straight away , strike your arc just under or right where you left off , get your pool and start your weave , do you do a root run first ?

 

[gavuk]

I usually choose the long arc technique.....in reality my eyes are not what they used to be .........do a search for Flange jockey......his pics and restarts are awesome

 

[martinr]

I usually choose the long arc technique.....in reality my eyes are not what they used to be .........do a search for Flange jockey......his pics and restarts are awesome

Thanks for that; I'll look for Flange Jockey.

Have you tried fitting a magnifier into your helmet? See
http://www.bakersgas.com/NAS101-MP-1.html

I use a 3.00 magnifier and it's like someone took the blindfold off. It's amazing the detail you can see. The point of focus varies with the magnification and I find that the 3.00 is not only a great magnifier but the point of focus is just about the distance I like to keep my head away. With lower magnifications, the point of focus is further away. It pays to get a couple of different strength magnifiers - they're cheap enough, so you can soon determine the best one.

Martin

 

[martinr]

There is another thread on here with some good tips , what size rod and what amps are you using , chip the slag off then wire brush but start straight away , strike your arc just under or right where you left off , get your pool and start your weave , do you do a root run first ?

Hi Tigman,

Yes, I've been putting a root run in first. I've been using E6013s 2.5mm on an indicated ampage of between 75 and 80A on DCRP (electrode pos). I know when I'm going to get a problem: I can see the weld pool starting to swirl around immediately after the restart. I understand your point about starting straight away to make use of the residual heat. Is the other thread by Flange jockey that gavuk refers to?

Thanks

Martin

 

[eil]

What strength reading glasses do you have martinr

 

[dai]

read this
http://www.mig-welding.co.uk/forum/showthread.php?t=13654&highlight=flange+jockey

 

[martinr]

What strength reading glasses do you have martinr

I don't wear glasses for reading or driving. I did have an eye test some 3 months back. They told me that, whilst my eyesight was better than average, reading glasses would help; however, as I can read newsprint etc without problem unless the light is very poor. I decided rightly or wrongly, that I should resist the use of reading glasses until absolutely necessary. I have to admit that I have problems reading phone numbers in the telephone directory unless I'm in bright sunlight. On the other hand, I look on the use of the magnifier in my helmet in much the same way that my dentist, who also does not normally use glasses, wears dental loupes to magnify her work area. I find that the magnification of the weld pool in both MMA and TIG allows me to see things that I can't otherwise see and allows me to make a more precise weld. I asked an optician if the use of a magnifier could damage my eyes and she told me it's no different to a watchmaker who spends much of his working day looking at the world through a magnifying lens.

I apologise if this level of detail is far more than you wanted.

Martin

 

[martinr]

read this
http://www.mig-welding.co.uk/forum/showthread.php?t=13654&highlight=flange+jockey

Oh, thanks for that. You can keep your Mona Lisa and other such art; those photos of the capping slag peeling back around the joint are pure beauty. I think I'd lift that slag off and have it mounted and framed.

Martin

 

[Tigman]

martinr , I cant think of the thread its about vertical uphand , when you weave you must pause at both sides and travel across the middle , I know what you mean when you say you can tell when the trouble starts , sounds like you may be moving too slow or as said not hot enough ! I personally use 65 - 75 amps but thats on my machine it is very low but always does the job . You dont weave on your root run do you ? the smoother the root the easier it is to cap , keep practising you will get it in the end !

found thread " Uphill Stick Welding ,....Help " have a browse !

 

[martinr]

martinr , I cant think of the thread its about vertical uphand , when you weave you must pause at both sides and travel across the middle , I know what you mean when you say you can tell when the trouble starts , sounds like you may be moving too slow or as said not hot enough ! I personally use 65 - 75 amps but thats on my machine it is very low but always does the job . You dont weave on your root run do you ? the smoother the root the easier it is to cap , keep practising you will get it in the end !

found thread " Uphill Stick Welding ,....Help " have a browse !

Well, I think I've cracked it now. I don't seem to suffer from the problem anymore and can get almost invisible restarts. As to what I did to solve it, I can't be too sure but I think in order of merit:

1. Stop worrying about it: just get on with it.

2. Use very small increments in the weave i.e. when going back over the previous leg of the weave, lay the new run over half of the previous run and carry on with such small incremental jumps throughout.

3. Don't go too slow (or too fast).

I strike up at the apex of the shelf of the previous rod's deposit i.e. where the shelf meets the root run, I move the rod back on a longer-than-normal arc along the right-hand edge of the shelf till I get to the last weave of the previous rod's run, hold for a fraction at the edge whilst shortening the arc and then move off over the leading half of the last weave carrying on as normal.

As ever, it seems the smallest change in technique sorts the problem out, along with a healthy dose of confidence.

Thanks to everyone for your kind help and advice.

Martin