Testing your welds !!

Talonmotorsport · #1 7th April 2011, 08:55 PM

Very nice work there Ronnie, perhaps you could put what rough amps you used to weld A,B and C.

Bonzo · #2 7th April 2011, 09:43 PM

Quote:

Originally Posted by Talonmotorsport

Very nice work there Ronnie, perhaps you could put what rough amps you used to weld A,B and C.

Hi Phil

To be honest, the settings I chose for the test pieces were deliberately askew in order to produce test pieces best suited to ilustrate this particular thread .... Came out quite well considering that the 3 pieces done were the only ones I did

My welder is a 180 amp set with power settings of 1-8 & a wire speed range of 0-10

Sample A was using power setting 2 with a wire speed of 1.5 ish ( Blatantly too low a setting for the material thickness )

Sample B was using power setting of 3 & a wire speed of about 2 1/4 ( not that far off the mark for 1.6mm, I would say )

Sample C was using a power setting 4 & a wire speed of just over 2.5 .... A tad on the hot side for a down hand butt weld.

My personal preference is to weld a tad on the hot side, in my view, there is no worse sin than a cold MIG weld

I also hold the view that a properly set up weld job will do more to aid the war on distorton than trying to reduce the heat put into the job .... The propper weld procedure/sequence will help greatly in the fight against heat build up

wylliezx9r · #3 7th April 2011, 10:06 PM

Thanks for that, very informative and great pictures. Although I bought my chassis complete I still need to weld a lot of brackets and such like. At least now I know what my welds should look like, even if I cant achieve it !

AshG · #4 7th April 2011, 10:42 PM

Well done ronnie im sure this will help lots of people with their welding.

its hard to make the welder misbehave once you know what your doing isnt it ronnie

i remember writing the welding articles for ckc and i found it really hard to do bad welds on purpose.

Wynand · #5 8th April 2011, 07:21 AM

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

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