Thread: Restarting rods

Hey Legion,

If I am doing stop / start welding, depending on the Rod I am using I used to grab the end of the Electrode with my gloved hand and bust off the concave flux bit, once I was more experienced It was a just second nature, Using a Auto Darkening Helmut helps a lot and you get used to just striking the electrode on a bit of a sweep, and it will all fall into shape, If you are trying to start start into an existing weld pool, you have to stop and get rid of the flux, If you ever get into Coded Welding Practices, it will be drilled into you that you don't get Slag inclusions if you don't have 'slag there to get included' everytime you restart, you should get rid of any Slag / Flux before you re-start. A sharp chipping hammer should always be at hand.

Hope this helps

HazzaB

Usually this sort of thing happens with low hy rods like 7018 and 7016 and is far less common with gp rods like 6013 and 6012 etc....
I have never had a problem restarting a gp rod because of slag on the rod. What I do with low hy rods is to scrape the slag off on the concrete with a gloved hand because if you beat it on the ground, flux always falls off at the stinger end too.

Also one of the things that influence restriking the arc is the open circuit voltage of the welding machine. If you are using a transformer type 240 volt machine, the OCV is around 45 volts and restriking will always be a problem. Machines which operate on 415 volts and the new inverter type welding machines generally have an OCV between 60 to 80 volts and restriking the arc is much easier. Also make sure that the electrodes are dry. If the electrodes have been exposed to the atmosphere for periods of time they will absorb moisture and this will increase the arc voltage. This will cause snapping out of the arc when using transformer type 240 volt machines. Electrodes can be redried in your oven at 100degrees centigrade for 1/2 hour.
Also take notice of the other replies. It all helps.

If find it's particularly bad with Satincraft rods and to a lesser extent RB-26's - a hard glassy coating forms over the end of the rod. I've got into the habit of scratch-striking in the area I'm about to weld (a tip from the best welding video I've seen) and while it takes a few goes to get a strike, it's less damaging to the flux than madly stabbing with the rod.

I find if a rod wont arc I just run the rod quickly along the steel so that it arcs and it will allow the rod to start to arc and weld. Bit difficult to explain easy to demonstrate. I find the problem is more the fact the flux has broken away from the end of the rod and exposed the bare rod.

Sorry guys, I should've given more detail in my initial post. I use a BOC Smootharc 130 inverter. I've got a fantastic Miller Digital Elite auto-helmet that makes welding 100x easier than the fixed lens I started with so at least I can see what's going on. The rods that prompted this post were 2.0mm 12XPs. It doesn't help that I'm usually doing really short runs so striking is hard. E.g. on the weekend I was trying to weld 4mm threaded rod onto 15mm x 2mm bar (repairing an electric grill of my wife's), so really only tacking so I didn't have much margin for error for striking. I will try some of the tips you guys gave me and see how it goes. Thanks all.

If there's no real estate to do a decent scratch, I'd suggest having a scrap piece of flat bar handy that you can attach to the work piece with the earth clamp and scratch on it 'till you get a strike. Then, with the tip still hot, you should then be able to bring the rod over and easily strike an arc at the weld point.

I was once advised to have a scratch piece with me at all times. If working away from your earth clamp, then the scratch piece can be right beside you held on with locking pliers.

You could well have an earthing problem .

The description indicates this. A check should be made of the connections.

This entails removal of the rubber boots that cover the brass bayonet connectors and checking thay there is sufficient fine wire cable contact within the sleeve which in turn resides in the socket end of said bayonet fitting.

The welding handpiece and earth clamp also should be checked.

Grahame

Nah, it's not earthing Grahame (although a timely reminder to check my connections - will do). I know it's not because once I knock the flux coating off on the bricks/concrete it strikes no problem but it's an uncontrollable wild arc until I burn away all the bare metal. I just want the repeatability of the first strike with a brand new rod every time - that's what I'm aiming for. New rods seem to have a perfect balance of metal/flux so they strike easily without sticking. The flux covered restarted ones tend to not arc and then I either do the tap-on-concrete-followed-by-wasted-bare-metal thing or I strike on the work harder and longer until they end up sticking when they finally arc through the stuck-on flux.

Kind of like lighting a new match on a brand new dry matchbox vs. an old matchbox with all the friction material worn off.

Try an old medium-coarse file, scratch the rod across it while it's still hot straight after a run and slag on the tip should come off easier. If that doesn't work just use the file as your scratch plate. Cheers - Mick

The funny thing about the 12XP rods is they are advertised to be easy to re-strike but are harder than most 6013's I've used. I simply suggest trying different rods as I just don't have this problem at all, ESPECIALLY after getting my Smootharc 130 a year ago almost. I love this machine.
Even Satincraft 13 rods are easy to re-strike when cold.

Gidday

Im also a fan of having a file handy. 'Pecking' like a woodpecker also brings good results with 'fresh' rods. The best parctice I have got into with my stop starts regardless of 'rod type' is to feed the rod through my free hand (typically my 1st 2 fingers) this gives great control and allows you (with a bit of practice) to keep your stop starts consistent and accurate................................

Regards Lou

Originally Posted by distractor

my Smootharc 130 a year ago almost. I love this machine.
Even Satincraft 13 rods are easy to re-strike when cold.

Same welder, same rods and I found them a bastard to restart until I changed from stabbing to the scratch technique.

The coarse file idea is a good one too.