3G 1" check it out

[cerbadeath]

I cut up a practice plate and took some pics. It's 1" plate welded in the 3G position, with 7018.

[G Austin]

The cap looks good on the outside but it looks like you have some pretty serious non fusion along one bevel. If your previous pass was convex that may have been the problem or too cold for the weave. A 1" plate needs some amperage and your may have been low. Who knows.

[cerbadeath]

I was running about 105 amps 1/8 rod. There should be no difference in welding 1" plate to welding 1/4" plate, as long as your welds are tied together the amps should stay the same. It's a 45 degree bevel with 1/4" root opening. As for the non fusion, I am not sure what you mean. Are you talking about the small gap under the the right bevel? That is actually a set up error. It's a combination of dirty torch, quick grinding and not clamping the backing strip tight enough to the plate. So it gets tacked like that and stays like that. But I don"t run weave passes through the plate, all stringers and a weave on the cover. Wouldn't trust weave passes through the middle to pass bend test, as I am trying to get my LA city cert. I am working on my overhead right now, maybe next week or sometime I will try and get a pic of 4G up on here.

[G Austin]

I will have to disagree with you regarding the amperage vs thickness. On a piece of 1" plate I could run a 1/8" e 7018 pushing 140. On a piece of 1/4" 115 would be closer to what I use.

As base material gets thicker the electricity melts less and less underlying bas metal since the base metal thickness increases the rate at which heat flows from the joint.

105 amps seems awful cold for a 1/8" 7018. It may make it easier to control the puddle but thats it.

I have marked up two of the pictures that refer to the area I speak of. This MAY be an isolated area of porosity that you by chance caught the edge of. Or it may be a length of non-fusion.

[cerbadeath]

Ohhh yes I see what you are talking about. That is actually a shadow of a bur. The band saw I used to cut it was dull and cheap. I cut the plate starting from the backing strip down so that area is near the end of the cut. I took another picture as close as I could to that area. I picked the bur out and there isn't any hole behind it. I would say it looks alright, huh? I would sand pad it down a little but don't have that handy right now. oh and the plate is up side down now.

[G Austin]

That looks pretty good. Your cap looked pretty slick.

[cerbadeath]

As for the amps though, I guess it depends on what you prefer. If your gonna weave the whole thing then I could see the amps being set much higher. If you got it low like I do, you will just end up putting in more passes I am guessing. How many passes does it take you to weave a 1" plate? I average about 20 stringers and then cover pass with these settings.

[G Austin]

Actually in some cases it does matter. Many shops and construction companies work within guidlines of welding procedures specifications (WPS's). And though by some codes they have liberty with amperage setting, in some they do not.

The AWS D1.1 Structural Welding Code allows the amperage range for a WPS to remain "qualified" for a specific procedure provided it is not set to "To a value not recommended by manufacturer".

Here is just one sample chart for various electrodes. http://www.hobartwelders.com/product...ectrode-chart/

One thing to keep in mind that at lower settings not only are non fusion type defects more likely, you are also going to be welding on a plate for a longer period of time. The longer you weld, the more time you have to mess up .

I really don't count passes unless a procedure specifies a given number of passes for a specific joint . I do try to weld within the range of the WPS if one has been provided.

Things that are often limited on a WPS are preheat temp, interpass temp, max thickness, min and max joint dimensions, pass thickness, heat intput, amperage, etc..

If you have been provided a WPS requiring you to run 105 amps, I would stick with it. It just seems very out of range. If I were welding some 3/16" material I would cheat the amperage setting on the low end if 3/32" electrodes were not available.

You have to do what you have been trained to do. I am just sharing some of my experience.

[moya034]

Looks nice.

Do you have access to a setup for bend testing?

I vote for cutting off the backing strip, then preparing some bend test specimens. That will really tell you how good it is.

[cerbadeath]

There is one at the school I am attending, but I think it can only be used for testing. oh well..

and Austin, thanks for the info.