Advice on choosing proper rod diameter/size,

[Big Wave D]

I have several question about rod sizing and a bonus one on technique:

1) I know that you can get 1/16", 3/32", 1/8", 5/32" sized rods. Also, it seems that the 1/8" size is almost the de facto size sold. However, what are the guidelines one is taking into account for which one to use so as to get the best possible results? I know that thinner materials need smaller sized, but what else should I be taking into account?

2) With given rod size and proper setting of amperage, does a 1/16" rod give the same penetration and quality of weld as say a 5/32" that is using a much higher amperage?

3) shade tree welder submitted this photo of proper beveling for good penetration. In it, he shows the gap between the two pieces as being the same as the diameter of the rod to be used. How am I trying to lay down that initial root pass? It seems like I'd be wanting to catch both sides of my pieces at once, but I'm not sure of the proper way to do that. In the past, I'd always had my bevel down to less than an 1/8" tip, but I would have the two pieces touching. I now know this to be improper. How do I get both sides and not have my rod just puddling down through?

 

[Shield Arc]

Big Wave D if your not working to a WPS, (Welding Procedure Specification) it really gets down to your own abilities. You have to learn what you can and cannot do. I'd say the average guy can go though life with just running 3/32, 1/8, and 5/32 inch rod.
A joint like shade posted there, you'll have to figure out for yourself how much gap, how much land you can use for what size rod, at what amps, and travel speed for each position.

Example: anything under, and including 2 1/2 sch 40 pipe I have to use 3/32 inch rod for open root, fill and cap. Just not good enough to carry all the iron a 1/8 inch rod will deposit. Now 3 inch and up to 12 inch pipe I can run 1/8 inch rod for everything. You need to do a lot of experimenting to figure out what works best for you.

 

[weldingisfun]

The more I weld, the more I find out how little I know about welding. Now, I am a self-taught amateur but this much I have learned, welding is not an exact science. As Shield Arc says so eloquently,

You need to do a lot of experimenting to figure out what works best for you.

That is why welding is fun.:thumbsup:

 

[Soundguy]

the 1/16 rod just won't carry the amps you need for deep penetration.. larger the rod.. the hotter you can weld.

I use 1/16 and 5/64 on a small 30/70a ac stick for tacking sheet metal together. anything over 3/16" I use my regular 235a buzz box.. 3/32 for thin stuff.. 1/8 for almost everything.. and have used 5/32 when welding like 1/2" + stuff.

soundguy

 

[Gary Fowler]

I would think that if you need a rod smaller than a 3/32 60xx rod then you are using the wrong machine. 1/16 rods just dont have the metal in them to do much more than spot weld really thin gauge like 20 gauge or thinner. WHen you get that thin, you need to be using a wire feed gun (MIG) Since I dont plan to start an auto body repair shop, I have nothing smaller than 1/8 in 6010 and 3/32 in 7018. Largest 7018 is 1/8. I personally never liked the 5/32 low hydrogen as they just dont seem to run right. If it is so thick that I need to go larger than a 1/8, I jump to 3/16". They run a lot smoother with less buck shot etc. I havent had a need for anything that big around my shop though and you need upwards of 200-250 amps to burn a 3/16 properly. If you are an amateur welder stick with the 3/32-1/8 max size. If and only If you need to weld super thin gauge sheet metal and dont have a MIG welder, would I ever buy a 1/16 rod.

 

[Big Wave D]

Another reason for this thread is that I'm trying to figure out what I did wrong with the top link lift arms from this thread:

http://www.tractorbynet.com/forums/welding/188909-7018-vs-7018ac-need-laymans.html

It's a long and rambling thread, so I thought it better to just start over with a new one.

When the arms broke again, after I'd welded them back together, I've been mulling it over in my mind about where I went wrong. I cleaned everything thoroughly and got 90% of the beveling right. What I'm not sure about is my choice of rod size. With my lack of welding 'skillzs', I'm thinking maybe I'd have been better able to control a 3/32" rod at the proper amperage for correct penetration, no burn through, and proper burn of the rod's flux coating.

My memory seems to be recalling that as I was using the 6011 rod (1/8"), I was on to hot of a setting, I'd started in the middle of its range and went down on the amperage setting after my initial try; so as to not burn through on the root pass, I dial down the amperage.

However, even though the breaks weren't in the exact spot, they were close enough, maybe shifted over by 1/4"+.

I had some people comment about a "cold" looking weld or lack of penetration, which certainly makes sense if I'd dialed back the amps too much, but I was also a bit confused as to the inclusion of the dark coloring in the weld itself, some form of contamination. I could see how this also might be a side effect of not burning the rod with sufficient amperage to have its coating hot enough to work properly in its shielding process. All this prompts me to ask, what does a 'proper' weld look like as you're welding, I'm going for Baby Bear Porridge here, "Not to hot, not to cold, Juuussssttttt right!"

Thanks to all for your help in making my welding better. :thumbsup:

 

[k0ua]

I use 1/16 6013 for light sheet metal, on as low as about 22 amps for low penetration, moving fast, trying like He** to keep from burning a hole stuff!
1/16 can work for up to 40 amps, maybe, anything more than that is just heat and light..poof!. 3/32 for the majority of my welding, and 1/8 for when it gets a little heavier, like 3/8 inch. I have never welded 1/2 inch material, I guess that is where the 5/32 and 3/16 and a bigger welder than mine start to come into play. I suppose I could bevel well and use 1/8 inch 6010 or 6011 to get there.
James K0UA

 

[Shield Arc]

Big Wave this kid has some really good videos on you tube. You may even want to check into buying his home study course. I really like how clear his camera work is. Just like looking through your own helmet.:thumbsup:
YouTube - Watch Great Stick Welding on The Welders Lens Home Study Course

 

[Big Wave D]

Shield Arc,

Thanks a lot for the link. I've been looking for videos on youtube, but having problems finding anything of length that seems like the person doing the video knows what they are talking about. Most of the ones I've seen seem to be of hacks with live leads.

It'd be kind of nice to have a sticky page on the welding subforum that is just of links to quality videos showing proper technique. I don't know who I'd ask about having such a page put up onto the site though.

 

[Shield Arc]

Big Wave trust me this kid knows what hes doing. He was a Boilermaker at one time. Only problem I can see is maybe he's a little over the beginners head, I think he touches more on advanced welding. But I could sure be wrong about that statement. Here is a link to his website.

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