Fillet weld strength testing

Christopher Tidy · 2005-08-31T06:20:40+00:00

Hi,Following our discussion about the strength of my two fillet welds, I decided to put them to the test.First I experimented with my technique a little. As Roy said that I was using too much heat if the tip of the rod was red hot when I'd finished a weld, I reduced the current from 145 amps to 115 amps (the next setting down on my welding transformer). I had problems. First the rod kept sticking to the work, then I had trouble keeping the weld pool in contact with both the horizontal and vertical surfaces. I had to weave up and down a little. And of course I ended up with some slag inclusions, like this: I while I thought I was getting used to working with less heat, so I tried making some test pieces. I cut some 50 mm lengths of 50 mm x 50 mm x 3 mm angle and welded them back-to-back: welded one using the drag rod technique (at 145 amps) and one manipulating the rod by hand (at 115 amps). The one where I manipulated the rod by hand ended up with a slag inclusion at the start, but I decided to test their strength anyway: tested their strength by clamping one angle section in a vice, then holding the other section in a mole wrench (vise grips if you're American) and bending it back and forth. I counted the number of complete cycles of bending each weld could stand before it broke: first sample (welded using the drag rod technique) took 13 complete cycles to break it. When it broke, it was actually the parent metal that broke rather than the weld: second sample (welded manipulating the rod by hand) took just one full cycle of bending to break it. This time it was the weld that broke: was a bit disappointed with this result, because apart from the slag inclusion this weld looked okay, and I had hoped it would perform better. So I made another test piece. This time I turned up the current to 145 amps, and again manipulated the rod by hand. I got a better looking weld without the slag inclusion. On the whole it felt better welding at a higher current: one took 6...

Aug 31, 2005 22 Replies

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Pete Keillor 21 years ago

OK Martin, you made me go look.

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Christopher, look at the recommended open times from hermetically sealed. When I say hygroscopic, I mean they'll pick up enough water from your house to be a problem pretty quickly. Gunner may get away with longer because he lives in the high desert.

Pete Keillor

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Martin H. Eastburn 21 years ago

That is good information - a bit odd - per this or that spec. and only those two. Hum.

Since I moved, so many of my documents or notes have found a place - but just where. The computer is here - the mind isn't.

I think the 5 audits on year 2005 by the IRS in the last 6 months has just about burned my short and some long memory.

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

Pete Keillor wrote:

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