Another advice question

This is directed towards Ernie, however anyone can make fun or respond as they see fit.

I am one of those "idiots" that buys a 110 MIG to play around. Absolutely NONE of my welding has been structural. Decorative items only. I have done some destructive testing (big hammer and cutting test beads), and everything looks like all the books say they should. I have had a few neighbors pop in to see my work, and they feel that I am running a good bead. But...... one of them has not run a bead since WWII, and the other owns an industrial tool company (you should see his shop!), and just messes around with welding (mainly TIG).

Ok, the question is.......I am wanting to add some tie down points to a trailer. The risk of weld failure could be very high (if the load is large and/or expensive). I have read numerous books, and run lots of bead........but I have never had a pro review my work. Should I trust that my skills and knowledge are sufficient?

Thanks for your time and patients with all of the questions.

Reply to
news junky
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Simple solution.

Make some test welds and try to break them.

Reply to
Ernie Leimkuhler

Also important to mention is that you should try to break them in the direction of the load, if possible.

If it is a cleat, bang it sideways. If it is a padeye, pull it off. Have a plan for what happens when it breaks so that you are ready for the flying chunk.

Reply to
Rich Jones

Hmmmm. Steps to test welding skill.

  1. Weld on new cleat.
  2. Put an excessive load on cleat.
  3. Inspect weld with the load still on the cleat.
  4. If the cleat does not fly off and split my head open...... I am good to go!

Thanks a lot everyone. I am still at the stage that I do not trust my work.

Reply to
news junky

After welding a ladder rack to mine. I find driving my trailer with my eyes shut much less stressfull :o)


Reply to
Ikie Cabolacov

If I might ad my two cents. Welding as a hobby, and a career is great fun but let us not forget the responsibilities that we all share on the road. I would hate to hear about a weld failure that killed a family of four on vacation. If I were you I would do as much beating and smashing on your test welds as you have the energy for. Maybe even go as far as nick-break testing your welds (Cut out a secion of bead. Nick across the bead with a hacksaw to 1/16" depth. Heat red hot with oxy/fuel, quench in cold water Put one end in a vice and hit the other end with a hammer to crack the bead open.) With a couple nick breaks you can see if you have left gas pockets, slag, or have poor penetration in your welds. Just remember the evils of MIG great presentation but poor penetration.

Reply to
Jane Hogan

Hi Jane, everyone

The bit about "heat to red hot with oxy-fuel and quench". Not met that one before. What does it do for you, that breaking "as welded" misses?

Nick-break I use at college and a damn' good test it is too. It's brought me down to earth with a bang plenty of times, correcting me of a woeful illusion that I was doing OK when the reality was different.

The one I know is "slice an inch-wide strip out of the weld, nick the weld top-surface with a saw, grip sample in a vice and break it with a hammer, if necessary knocking the breaking-off end backwards and forwards to fracture it off". We then look for fusion at the root / corner of the weld. That's pre-assuming no gross defect like absolutely no fusion down one side of a MIG weld, and we sometimes do end up gathered around in wonderment looking at one of those. Bend around a radius of set relationship to joined plate thickness seems to be the one for butt (seam) welds. Nick-break seems to be used for fillet-type welds - T-joint, lap, outside-corner right-angle.

In UK, nick-break is apparently covered by British Standard 4872, though must admit never looked it up myself.

Richard Smith

Jane Hogan wrote:

Reply to
Richard Smith

The answer is very simple, really. It is: no.

You should not trust your welds.

But come to think of it, nobody should trust welds, really. Especially for things like trailers or airplanes where any failure might be catastrophic. So the real answer (and the one that is used in the industry) is check and design.

Check, like you check your welding ability (what you've been doing by braking a few welds), you check your welds (difficult for a private person, since you need X-rays, but routinely done in industry) and you check your trailer from time to time to see how the welds hold.

Design, like you design the trailer so that no excessive stress is put on the welds and you design the trailer so that it won't fail catastrophically when a weld breaks.

Rule of thumb: the trailer should not break appart if any two welds break. Note that this should be attained without adding more welds.

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