Thanks Allan,
I was looking for that, I think Metrinka posted it awhile back on here somewhere, but I didn't see it on my quick search.

Absolutely amazing Allen! What don't you have pictures of?

Jeff brings up an excellent point! If you are trying to judge the amount of purge being adequate or not, then these charts are helpful yet, should NOT be considered as the most accurate method of determining whether or not a sufficient amount of purging the O2 content from the atmosphere around the backside of the weld was successful or not... There could also be some other factors which could cause some misleading discoloration which may have been overlooked also...

If the backside of a SS welded joint wasn't properly cleaned, then a discoloration can also occur if this precaution was not even considered and maybe easily overlooked initially especially if one only focused on purged time, and not paying attention to the other factors involved besides just monitoring the amount of oxygen in PPM's (Parts Per Millions) within the atmosphere located around the backside of the weld joint...

Also, if you are trying to determine how to judge the weld seam by its color based on what one notices from viewing the weld seam from the front side of the weld joint, then these charts are very often very misleading and should not be used as a reference guide in that sort of application of visual inspection. ;)

Jeff knows a heck of a lot more about all types of stainless steels than most in here including myself, and I always value all of his observations in here even though I don't always agree with some of them!!! :) :) :) However, when it comes to Stainless steels, he's one of the most knowledgeable persons I have come to know regarding the heat input, heat treatment, welding & post welding heat treatment difficulties often encountered when joining some of these particular grades of steel. ;)

These charts are good and useful guides, but should not be used as the end all, gold standard in determining the proper amount of oxygen being displaced from the backside of the weld seam because a decent, calibrated oxygen analyzer will do a much more accurate job in measuring that...

So making sure that all of the factors are considered is the best course of action to take in the final analysis when determining the actual causes of weld discoloration found on either side of the weld seam. ;) I would not as Jeff so eloquently pointed out, depend on the color charts alone in determining how much oxygen the weld seam is being exposed to regardless which side of the joint one is referring to. ;)

Respectfully,
Henry

Like I mentioned earlier... A reference chart is only a "GUIDE", and not an "end all - Gold Standard" when setting criteria for accurately determining the amount of oxygen a weld has been exposed to based on color alone especially when one has to take into account many differing atmospheric conditions, whether or not the welds were performed close to sea level or at higher/lower altitudes, dew point variations, quality grade of shielding/purging gases, etc...

The only way to accurately reference a color chart for one's own specific location is to take all of the factors listed above and use them as they pertain to one's own specific environment/location, because as some of us already know welds do not come out exactly the same unless all of the important environmental conditions are exactly the same, and most of us already know from experience that in reality, this does not happen if one compares the welds produced in let's say - Pittsburgh, PA and Death Valley, CA or Miami, Fl and Denver, CO so long as the differing environmental conditions between these locations are not controlled enough in that there are no variations between them. ;)

Therefore, the environmental conditions surrounding the reference photos of discolored SS welds will ultimately have a role in determining whether or not they were produced under the same environmental conditions as where one is performing their own welds in order to produce the same results. ;)

Respectfully,
Henry