Welding rod

[Speedy Builder5Participant @speedybuilder5]

I have used stick welders for over 60 years, but never came across this problem.

I had been busy welding up some more track for my 5″ loco when the next rod refused to “strike”.  I assumed the welder had got too hot and it needed time to cool off a bit – even though it had not been hard pressed in service or the over heat light on !

I made a cup of tea, and returned to the welder but it still wouldn’t strike.  The over heat lamp was not on, so I took the cover off to investigate.  It’s a simple welder (no electronics) and both sides of the thermal cutout were live (OK).  Nothing else seemed out of place, and there were some volts coming out of the electrode grip. So that wasn’t the problem (I could have tested that first – silly me!)

For some reason, I changed the electrode and it was all working fine, so I used the original electrode and it would not strike.  On bending the electrode it snapped in half showing a very poor joint in the electrode wire, just enough to hold it all together.  Never seen that before !

Bob

The electrode at fault is marked with three white dots!

[noel shelleyParticipant @noelshelley55608]

Like you I have been welding for over 50 years and NEVER seen that ! It is interesting that the rod should be marked, may be should have been removed at the factory but got missed ? On the same subject I have seen cheaper welders where the mains supply switch or other connection points have failed over time due to poor contact, heated and cooked things close by . I had a modern inverter welder where the 160A output was using a 6mm bolt that could not take the current, heated and failed. I was able to drill out to 8mm and make a good connection, then all was well. Noel.

[larry phelan 1Participant @larryphelan1]

I came across that once only, a long time ago. I assumed it was just a bad rod and changed to another. Later on, just for the hell of it, I chipped the flux off the rod, which then fell apart in two pieces. Not very common, but I suppose the odd one does get through. Always worth changing the rod before stripping down the plant !!!

[Robert Atkinson 2Participant @robertatkinson2]

I wonder if the wire feedstock was multiple lengths welded together to make a long roll length and one of the welds was bad.

 

[noel shelleyParticipant @noelshelley55608]

At 2mm, 3.2, 4mm I would assume the feed stock comes in on large drum or reels, again an assumption that the coating process is continuous and as one reel runs out the new one is spot welded to the tail of the first reel. In this case not very well and hidden by the coating. Noel.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi, I’ve probably used a few thousand stick welding electrodes in my life, and have never had one  like to O/P has spoken about, although I have had to use some fairly rubbish ones.

Regards Nick.

 

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