Quickie turned Biggie

Gary Fowler · Nov 29, 2011

I finally finished (I think) fixing up the stabilizer pads off a JD 310 backhoe for my building contractor (Ricky) It started out with just a patch job on some broken tips (3) on the pad which would have been about an hours work counting preheat and bevelling of the pieces. Then we talked about putting some cleats on to prevent sliding so I welded on some 1" bar stock from an old disk axle. This took me about 6 hours yesterday. This morning, he bring me two long pieces of old rusty angle and wanted them welded crosswise to help with floatation in soft soil. So, I put the pads back on my table and put a heater on them for about hours with a piece of roofing tin over the top to direct all the heat on them. It worked pretty good and got the all warm to the touch. The welds tend to underbead crack if not preheated. It took me another 5 1/2 hours of welding, not counting the preheat prep time to get all the old rusty iron ground down a bit and cut to length. I ended up burning about 30 pounds of 1/8" 7018 rods on this little quickie repair. You can see the tips repaired that dont have a hole in them as shown in work done yesterday, then final I hope version finished today.

Car Doc · Nov 29, 2011

Nice work! Yeah when a person starts figuring time and materials it adds up a lot faster than a guy realizes hope you get paid well looks like you worked for it and should give him no-skid pads. :thumbsup:

Gary Fowler · Nov 29, 2011

Well actually it's a freebie, but I will get a few things for it. I have him building a 14 x 30 extension on my shop and after getting the quote, I added in a 32x55 window and a 32" mandoor that I will have him install at no cost and also extending a 14' wide x 20 foot concrete apron in front of the equipment door. Hopefully he will give due consideration to the costs of those additions when he sees his pads. It would have cost him at least $500 in labor cost for this work at a shop figuring $50 per hour + material. It took me a good 10 hours of work to complete it all, plus several pounds (estimated 30#)of welding rods and O2 and acetylene+ I used up a new 7 1/2" X1/4" grinding blade cleaning up the rusty material and weld prep not to mention the electricity for the welding machine and shop lighting.
He is a good guy and did a good job on my house @ $80 per heated square foot and less than $55 per sq. ft under roof cost with lots of extra work at no charge so I figured I owed him a little something. He also built my brother in laws house and shop.

Gary Fowler · Dec 1, 2011

Well, guys today I welded up his FEL bucket on his NH TC40. It had cracked at each skip weld in the back of the bucket (4 ea) Man that thing was thin. About 1/8" plate and magnetic in several spots which created lots of arc blow. Took me about 2 hours on that. Maybe I will put out a Welding sign at my shop. He did offer to pay me for it, but I didnt feel right about that when I did the big job for free.

Shield Arc · Dec 1, 2011

Gary Fowler said:
magnetic in several spots which created lots of arc blow.

How did you combat the arc blow? Change directions, move the ground clamp, switch to AC and some 6011, heat the area cherry red?

Haywire · Dec 2, 2011

I've been moving the work clamp around, but can't really tell that it does any good.

dstig1 · Dec 2, 2011

Yeah it doesn't do much... You can either go to AC as SA said, or you need to do something else. Heating the metal up until it loses magnetism and letting it cool is one way (dull red? I forget - easy to look up online). If the metal is magnetized, I'm not sure there is another way - heat it up or go AC. If it is due to eddy currents then your solution comes with better tack weld and ground placement.

Shield Arc · Dec 3, 2011

Haywire said:
I've been moving the work clamp around, but can't really tell that it does any good.

If you're just doing coupons this won't be of much use to you. But if you're splicing beams, tube, pipe, or anything that has some size to it. Wrap the ground lead around the object 3 or 4 times, if that doesn't work, wrap the ground lead around the object the opposite direction 3 or 4 times.

dlauffenburger · Dec 3, 2011

Gary,

PLS forgive the dumb question, but do you heat it because it is cast iron or is there some other reason?

Gary Fowler · Dec 5, 2011

It wasnt cast iron, but some grade of cast or forged steel. I think it was super hard just from the ringing sound it made when hit with a hammer and it was not easy to grind on. It threw out small light red sparks. I found the need to preheat above 100F when my tacks started breaking as I welded up the other side. When examining the tacks, they were pulling out some base metal so it had underbead cracking which is conducive to hydrogen embrittlement, but since my rods were hot and dry, I didnt think that was the problem. I found that with a bit more preheat, the cracking problem was nulled.
As for the arc blow, I just welded thru it and let the buckshot fly. Once it got hot and the first pass was in, it wasnt a problem anymore. I just had to really work the puddle to make the weld metal stay where I wanted it. A couple of spots, I just skipped over a few inches and found a spot where it welded OK then came back and filled in the magnetized spot. Heating to above 450F usually reduces the magnetism to a weldable level. I didnt want to waste my fuel and oxygen and instead, just used the heat of welding to get it hot. Like I said, once it got hot with the first pass in, then it welded fine after that.
I have did the old wrap the lead trick before also, but find that heating it up works best. Sometimes it will come back when cool though. I have seen pipe with high enough magnetizm to hold a 1/8" 6010 rod in place.