As a retired qualified boilermaker with 35 years hand on experience, during my tenure at that also held a coded welders ticket, I will give my humble view on this.
Plate C in my view was the best piece looking at post one without even looking at the other pics posted. Fusion was excellent with parent material, the cap really very low / flat that will lessen HAZ in a big way. On the flip side of the plate one can see that the penetration was good.

For the non professional welder; big fat caps / beads are not stronger, in fact the opposite is true. When I still welded as a coded (X-ray), the max allowable cap was only 1.6mm and that's on big bore pipes. Bigger caps were failed due to the unwanted stress resulted from that.

I agree Bonzo, it is better to weld rather hot than cold,. The common sin of most amateur welders are the fact that there current is to low. A simple trick to set one's welder to a specific electrode (rod) thickness, is to multiply the diameter with 40 and that will put you in the range of a good weld - vertical up welding needs some downward adjustment if needed. Eg; 2.5mm (12#) electrode x 40 = 100amps.
Furthermore, Im always skeptic of nicely grind-ed welds as your pics shown for the simple reason you hide the tale the cap has to tell...
A nice bead such as "C" looks more professional than a grind one and I would rather see such a weld bare.
At the end, a destructive test - like the bending test you did - will be the decisive factor for quality of weld.

Lastly, kudus to you for the effort to post this excellent post and the trouble you took to do it. I believe it is an eye opener for a lot of people not well versed in welding strength:cool: .

Really nice example of welding, should help people get their welding set up correctly.

Great Post Ronnie

Im sure this will help lots of people with there welding

tilly

Brilliant!:)

Well done Ronnie, a cut across the welds would reveal what to expect from bad welds.

Did some NDT and ultrasonic weld testing in my spotty youth as apprentice welder,very interesting.

IMHO this is so informative that it should be made a sticky, questions are asked all the time about welds, and having such informative images gives the novice welder a clear image of what he is trying to achieve, you can talk welding all day but a few good images like the above make all the difference.

I personally agree too,

so,

I,ve asked permission( afterall, its Ronnies thread) from Ronnie if he would be happy for this thread to be made a " Sticky", & he is more than happy for this to happen,

Thanks Ronnie, great work :cool:

cheers
andy

I feel as tho its a competition now :) i have a pic that may be of help and certainly dont mean to blow on ones own trumpet but i have a pic of a t fillet i did when i was about to do my coded , i feel this may show how the weld profile should sort of look :)


http://i1134.photobucket.com/albums/...r/IMG_0503.jpg

was done with a migatronic 545 i believe :P mmm beautiful machine!

Oh well my chassis might a well go in the bin then :-(

Nice weld ! I was always taught to fill the crater and have noticed on some welds this is not done,comments please.

A weld without gas cut in half would be interesting.