I have to do some welding on the bobtac on my 743 to repair some cracks in it. I can't remember which rod to use to fill the cracks and then plate over the area where the crack was. I believe that I used a 7018 before but cannot remember for sure. Any help would be greatly apprectiated.
That's what I use on most everything
7018 is about as good of a rod as there is for the kind of welding you are talking about. When you go get them be sure to make sure you get the right series 7018. The straight 7018 is for use with a DC welder and can be used reverse polarity or straight polarity. A 7018AC is also available for AC welders. ointhead
Bobcat 743? Lemme guess...it broke the pin boss weldment where bucket tilt cylinder attaches to loader arm frame.
Always have 7018 on hand as well as 6011. The 7018 like was posted above is about the best all around rod there is and very strong and weldable in all positions. 6011 is a great field repair rod for some things that are not able to be cleaned as well...we call it a dirty rod. Most of all...spend the extra time doing your prep work. Even the best welder or rod in the world won't last with poor prep work.
First of all thanks for all the replys. Willie59 that was what i fixed last time i welded on it. This time it has cracks where the latches are on both latches. The cracks are only on what I would call the inside both facing the tilt cylinder. I also have to replace the studs that the latches bolt to, do these just press in? Thanks again to everyone responding you guys are great help.
It's been quite some time since I've worked on a 743, don't really remember the arrangement of the coupler. If it's like the later model Bobcat machines, they use a long 3/8" bolt going through a weld in bushing that the latch pin arms pivot on, then the spring/washer/nut hold the latch arm on the pivot bushing. If that's the design the 743 uses, and the bushing is worn/damaged, you can get a new weld in bushing from Bobcat. I've had to replace the latch arm bushings in our machines several times as we handle tons of attachments with our machines, far more than what normal use of Bobcat latches would be.
7018 from a fresh can should be just what he DR. ordered
What I do with the 7018 is bake them in a warm oven. I use an inverter welder with the leads reversed but only use the low hydrogen for high strength work and 6013 for general run of the mill work............
Stock do you mean dc-? I use my inverter on dc+ (from memory) because it gives better penetration. Am I right or wrong?
No she on AC but I have the leads reversed rod to the negative socket.......................... I'm running 160amp inverter with 3.2 mm rods and never have any penetration problems.......................
Depends on the make, but mostly 7018's should be run electrode + ve, as the heavy coating needs more heat to burn off. Try it and see if it makes a difference, Stock. They are generally easier to use electrode +ve.
6013 for the root pass and 7018 on top. Iv'e also found that 7018 electrode+ is best for metal together and electrode- for any hard faceing. Seams in negetive the weld stacks up higher and doesn't penetrate into the base metal as much. When I was in welding school I was told that this is because of the direction of the flow of curent. Curent flowing towards the work causes the heat and rod into the work were as in reverse the heat is drawn toward the rod.:my2c
Reverse polarity only works good with a DC machine. You can't do a good job of welding with an AC machine reversed.
What kind of welder are you running Stock? I've never seen an inverter capable of AC that I can think of.
There are a lot out there, Alco. Most major welder manufacturers make them. I use a Murex/Esab unit that will TIG and MMA AC and DC. Good unit, but more for repair than production. Stock, if you're running AC on an Inverter it won't (shouldn't) make any difference which way you run it, but try it on DC, you'll most likely find Electrode + slightly easier and DC- slightly harder.
Good to know. Any inverters I have ever used or been around were all straight DC machines. I just assumed they all were.
They just get a lot more expensive for both modes.
7018 is still as good as you can get for general welding on construction and mining equipment.
inverter capable of AC? hmm haven't tried it... ever since I had my welding training ..
7018 is my the rod I use the most, really need dc rev to do the best job. They make an ac 7018 rod, but it's not the same. If all I have is an AC machine I like to use 6011 rod. One other thing to keep in mind if your welding a forging or a cast steel to preheat to around 400 deg before welding.
Some of the older AC machines had two working voltages, 50-60 or around 80, the higher setting being better using some of the heavier coated rods, like 7018's. Not as tidy as using DC, the downside being increased splatter, but still capable of a fully fused weld with 7018's.
I use 6010 3/32, dc electrode pos, for a root pass on any crack repairs. This ensures the all the contaminates that has found it's way in the crack has been burned out. 6010 is a dc rod, where as 6011 is an ac rod. After grinding the root pass, I cap with 7018 or wire feed.