JD 637 Disc Dillemma Part II (photos)

To start off, I HATE, did I say hate, when you go to press the post button and the D%$#gd power goes off at the same time !!!!!! What are the odds ?? Ain't the first time either, there must be a small battery back up for a PC, be it a squirrel tripping the breaker on the pole or some other nonsense, sure makes you feel good about paying that delivery fee and about ready to pull ones hair out when you lose your work don't it ? Well enuff on that....

Here's the deal, this shelf angle, ( if you saw yesterdays post (tillage and welding experts) has ripped apart, I welded the failed areas, and it ripped elsewhere, so I carefully burned it off, then installed a new one, the welds are multiple passes and are a little fat in profile towards the top, furthest one in looks off, but that is just the top checked by grinding and saw no porosity, yeah looks like overkill, but his son said weld it good, so I took him seriously. I know it will hold, the previous angle showed no sign of coming off with the factory size welds, think he made me a bit paranoid that it could come off. Welding sure is an art, arc distance, puddle control, things in your way, weight of the stinger line (I drape it over my shoulder), combination of those made it difficult for me to weld the under side with the gang flipped up, kind of vertical down, at a slant. 5/32" electrode was sticking, even with the heat up, ground those out, no porosity, just looked like crap on top, went back to 1/8" lower heat, and that made a big difference, looked a lot better, just can't leave something for someone else to see and have it look like crap even if it is strong. No shots of those, got dark, running out of time etc., but good for discussion learning, vertical down welding does not seem that difficult, when things are set up right, but is impossible when not from what I have learned so far.

So what in heck could cause this 1/2" angle to fatigue and fail? 1st time it ripped, in the center, then at the outside corner, welded those up, failed at the outside corner again, but not the welds, middle held up where I welded both sides, but new tears were near the slots, no more welding on that one. I can't figure it out, only thing I saw was that when I bolted er back up, the 2 outside ones line up when the wing/gang is raised to the flange above, then the inside bolt, you have to set both down and pry over a bit, maybe there is a kink in the alignment for raising up for transport ? If it happens again, he's got to get someone from the dealership out, get that book on it out etc., I've watched it in use in the field, they raise it at the turns, seems to be adjusted/level/depth set within reason, but I ain't no expert, just seems to appear like it's cutting in right, though we do have some fields with basketball and larger size rocks, I've been picking them for him as he tills.

Am I correct in seeing it has cracked at the margin of the weld and the square beam? If so here is a trick I learned welding on discs to make pedestals for grinders. The composition of the disc is a high quality steel and to make a weld hold on it it had to be pre-heated and welded with low hydrogen rod (7018). If the flange is failing I don't really know the answer. I would be tempted to make a flange that wraps completely around that beam instead of stressing the welds in shear like they appear to be.

Nope, that angle is new, and just welded on, same as factory, well the weld profiles are different obviously, angle to tube welds hold fine, was the previous angle I repaired after the farmer had been complaining about the adjustment of that side, the thing was torn and out 1" at least, I clamped that torn angle back in place, welded er up and she ripped in new places, well except the outboard corner (outside end), could not tell what happened there actually. So the old angle was cut off, I cleaned up the tube, filled some minor nicks from the torch, ground clean, and started over, and is what you see in the photo, just waiting to see what happens in the field and am really wondering what in heck could be working so much torsion and or stress to that sucker. Off today and finally some time to catch up at home once I've rested up, theres no doubt about the hard work of farming and similar work, these kind of oddball problems sure can be relentless until you figure it out.

meant to say when he was concerned about the adjustment, ends digging in too much, that is when I discovered the first time the angle was ripped, no photos of that, but she was going to come apart, 2nd time she was on her way out again, told him to watch it and he got away with the last field to disc before he was going away for a few days, we did at least wrap up that 40 some odd acres, would not have been much longer, would have come off.

We adjusted and tried it out several times until he thought it was good, meaning nothing excessive/ground engaging to cause this. I'll be darned if he or whomever else is discing is turning with them down, they been at this too long to do that, and sure in heck know better, the son says he uses em like a corn planter, head lands then straight runs or vice versa, but not turning in the ground, boy I sure hope that aint it either, as I do not want to do this repair again, though I have a spare angle on the shelf for him yikes !!!

Billy, can't help out on the disk, but I can relate with the computer power problem. The farm I live on is under powered with 100 amp service, and whenever I'd fire up the wire welder the computer router would mess up and finally fail from the voltage dip/spike. I finally plugged my system into a TRIPP-LITE brand (no, I'm not endorsing a brand) battery backup and all problems were solved. There's no more re-booting after a power blip and the router has worked flawlessly. Sorry I can't tell you where to get one cause I bought it from the satellite TV guy. Jim

Jim, I appreciate it, and I will have one asap, that was the last straw, I called the power company and told them there tree cutter left problem trees, the unreliability of the service and said I hope this is not another series of outages like we were getting before. They've had subcontractor line crews putting up new circuits, Asplundh doing tree cutting and trimming in this area and I said, it's a darned shame your lazy @ss managers are not following the work and making sure things are right, comeback/remobilization is in-efficient and more costly, you've had resources in the area numerous times, what the heck is the problem. I see a huge rotted limb over primaries, next t-storm or weather occurrence will drop that one, and it's on the same damned tree that dropped/stretched those lines to the pavement 2 years ago !!! Out for almost 24 hours, hot, humid, elderly person in the house and of course it took some real pestering to get someone on the scene, though there were multiple breaks, weather occurrences the subcontractor line crews were over 100 miles out, yet they had another very large crew on site from the same company nearby doing new circuits. issue an emergency change order and send em out is what I would have done, so what you're tired, this is part of the job and why we pay you, get it done !!! This is a tri-city area and we used to have 2-3 yards fully equipped with in house work forces line crews, not since the acquisition by an international firm though. We pay more for less..... you know the deal right ??

Well, I went back and checked in on the JD 4440 and 637 disc working a large field, so far so good, he was 3/4 done with 2 passes, and not one sign of fatigue or stress on the angle or welds.

Billy,

That is sure a good looking disc compared to the older stuff we run. But maybe because we run older stuff often bought at auction we have gained some more experience in diagnosis and repair. I would wish that not to be true!

I am going to assume that the black disc frame bolts tight to the upper green frame as they seem to line up. Interesting that the green piece of similar thickness angle has not failed. But notice that the front end of the green angle has a gusset diagonal to give it more strength. If you have any further failure then add gussets to the ends of your replacement angle.

Now as to what might be causing the problem, assuming that we can eliminate operator error. Front gangs usually take a much tougher beating from big rocks, and so this may be part of the problem. But I do some careful measuring to determine that the hinge pin in the black frame is parallel with the line of the upper green rectangular tube that is pulled by the hydraulic cylinders. This disc may have been assembled incorrectly when new. Or maybe someone has bumped the front corner on a tree stump at the edge of the field, forcing the right front gang out of alignment. I see that the gangs are cushioned with the big horseshoe shaped springs, and that may have saved the gang bolt from breakage if hit. Measure carefully on both sides of the disc, and I'd bet that this front gang is slightly back of where it should be at its outer end. You are going to have be creative in measuring to either prove it is bent or prove that it isn't. I doubt that you can do the measurements working alone. I would also guess that the hinge pin on the rear gang must be parallel to the pin on the front gang.

To make a vertical weld with 6011, I find it easier to weld from bottom and travel up, meanwhile holding the stick at about 45 degree upward angle. The 6011 aims the heat quite effectively in the direction the rod is pointed. Keep your arc length short, less chance of the puddle running away in a big glob. If you are having too much trouble with the puddle running down, then just strike the arc and make a single left to right pass and let it cool for a few seconds. Chip off the slag and make another pass preferrably right to left. Weld, stop, chip, as often as you need to get the bead length you want.

You are a good man to help out the "old timer" fellow. I have done the same thing many times and have much respect for others who are willing and capable of helping.

Best regards,

Paul in MN

I used 7018 all around, though I need to get some other electrodes like 6011, 6013, I'd also like to take a vo-tech class on welding to refine my skills further, the vertical welds were a bit of a challenge on this, I did lay more than enough material in there to make a solid connection, ground same and saw no porosity, though I had some sticking problems, when I went back to 1/8" electrode, I could run a continous bead, so although it don't look factory, it don't look cobbed either, she's on there, I could always run final passes to make it look better, but once I know it will hold, which it has so far. When the gang was flipped up, it was sloped so not totally vertical, and I could see that I was gaining on doing that position much better than in the past. that slope helped, but the gang of discs in my way, really made it a challenge to get a stick in there at the right angle, maintain arc distance, not stick and not stop short etc. If I took that gang off and flipped er upside down, the profile would look professional if I could weld on the flat, but at least it has held, sure is enough weld on it, especially up top, which was never the issue in the first place, and if it failed, could still be burned off again and re-done, I just don't want to mess up that tube it's welded too, or embrittle same by welding and cutting on it too many times. That technique you mention, left to right, short pass, let cool, I've seen welds done like that, my truck frame was extended, and the profile looks like it was done that way, a much looser stack of dimes, but still solid, just takes more time, will remember that, I really need to practice the vertical position more, though on the old piece of angle I welded the cracks and it looked perfect, turned the heat up and it fused right in but good, much flatter profile, with excellent penetration and strength, it held, I saved the piece. So many variables that can effect your welds.

There are large enough rocks in these fields and what you mention about assembly I too have considered, though this one has been in service 2 years, think this year is the first he's had trouble. Might have been a one time event, and that piece of angle was just fatigued out. He bought a large JD rotary cutter, and they put the blades on backwards when assembled, so I can see these things happening. I think this might have been adjusted wrong as I helped him adjust the front to back level and something was off, might just have been that front gang was just down too far, large rocks, lifted too late after a turn 1x too many etc. I checked in on it in the field and being coated with cold galv. spray which I use on all repairs til they can be painted or what have you, I saw no signs of stress. The bolts were also loose since the last repair, I tightened em good this time before it went to the field, could have been that play in the connection working on it too. I also gave it a good once over, did not see any signs of stress, like fractured paint, or new rust elsewhere on the disc. Time will tell, though you do have to check, adjust and tighten things on something like this. She also takes quite a bit of grease, which I did also, to make sure it was ready.

In the last few years he's gotten some new equipment, but he's no different than most, always bought at auctions, he sold some land in the past, and at his age, probably figured what the heck, late model JD 7420, this 637 disc, new JD round baler, discbine, rotary cutter, but that 7420 tractor is sweet, he has not bought a new one in a long while, funny, the steel supplier, one of the partners used/borrowed it in his wedding, another friend shipped it to the place, no charge for the steel I needed! He's real careful when it comes to money, and I don't blame him and you have to admire someone in this racket who can make things work all these years, it's been a pleasure working with him this spring, he's well ahead this year. He bought a grain drill at auction this spring, did 65 acres of oats with it and boy everyone of those fields I cultipacked sure looks good, the thing worked nice, though we had to freshen it up, lube and check er out, for what he paid, the auctions are the way to go, he's worked on enough old stuff in his day I am sure, builds character like you said with diagnosis and repair.

He's really appreciated the extra help this year, his kids sure are busy, but 2 of them still jump in when they can, but just having an extra hand like I've been, full time for a few weeks, really makes a difference, it's low pay, but satisfying to be able to help keep things rolling, and know it's appreciated, and at his age, doing what he does is not easy and sometimes difficult to do by yourself, I know he enjoys the work, though sometimes he breaks even, but with a little help, things sure seem to go much better. The last week or so was on me, he's got some standing timber to come down to expand a field, so that works out ok for some compensation, no out of pocket costs for these repairs helps the bottom line on his end. Some people are terrible for what they charge, he had a guy do $3000 worth of work to his '90 checvy 3/4 ton, trans. etc. darned linkage was off, would not stay in park, he had the guy come back, he fixed it, and charged him an extra $10, just had to get something, some people are just rude like that.

Billy,

I've just spent the day doing tillage with a 20 ft field cultivator behind our 1970 Ford 9000 with the duals on. So my brain is a bit scrambled. As my son said, that old tractor just did as nice a job of seedbed prep as a newer $100,000 tractor would have done. Much of the difference is a really quiet cab and an air seat suspension, so for big payments you get creature comforts, but the soil doesn't care what pulled cultivator. And the soybeans don't care what color the tractor is.

Just a thought about your welding experiences. My experience as a good and capable farmer (and I have taught some basic welding classes), but not as a professional welder, is that the 7018 is very hard to make a nice looking vertical weld. It does not "focus" the heat the same way the 6011 does and does not give the weld puddle a quick "freeze" characteristic. The molten bead wants to run and may freeze and stick after it has run a bit. Thus the big globs that form from the drips. If you run that 7018 with AC, the vertical problem is even much worse. There is a magnetic field created by the arc, and with AC the magnetic field is constantly changing direction following the 60 cycle power. This throws the molten metal all over with a great deal of spatter.

One trick an old time welder/blacksmith showed me is the use of the 6011 to make the deep penetrating "root" pass in a "v-ed out" thick metal repair. It tends to boil off some of the carbon and crap which is in the base metal. Then build your stronger 7018 weld on top with succeeding passes. Now you get the penetration and better first pass weld control and the higher strength and better final look of the 7018 for your finish product.

The 7018 does not have the penetration and tolerance for rust, paint, oil, grease that the 6011 does. Besides the 7018 is hard to start the arc unless you have ground out a real clean area to weld on. I am not trying to sell you on either one, because they are the 2 most common rods I use for our equipment repair. I also have a 250 amp MIG setup (with 75/25 argon/CO2) which gets the most use. The mig is easier to start the arc and mulitple passes do not need any chipping. But the mig likes cleaner metal and the 70 series wire gives good strength, but does not give the penetration the 6011 rod does. So each has its advantages and disadvantages. Getting familiar with them all will make you a better welder. With the mig available, I see no use for ever burning another 6013 rod...and I have 10 to 20 lbs of 6013 on the shelf. I used to use it prior to the mig purchase.

I should bring fuel to my son who is still planting soybeans. We expect rain tonight and the soil is just right for planting. He was on the field till midnight last evening and started before 7 this morning. Besides he works full time AND passed a 5mm kidney stone late yesterday. He didn't have time to be hurting, so was running equipment while loaded up with Vicaden. I was worried about him making some nasty mistake while running equipment and being drugged up at the same time. I used to have that kind of drive, but there isn't enough energy left in this 63 year old body for that much abuse.

Take care, and have fun with the welding!!

Paul in MN

Paul thanks again for that bit of info, have to print that out and re-read, what you describe makes sense, I've agree with 7018 and vertical, but I saw the last passes I made today, when taking a look at the disc, I got 2 in there that look decent, with the root passes underneath, ground and no porosity, she will hold and don't look bad at all with the touch up paint he put on over my cold galv spray. Good news is, my friend about 10 years your senior said he's done another 20 acres with it 2x/2 passes, I think that front gang was set too low, not levelled properly and someone did not raise it up enough during a sharp turn, book probably is detailed about the correct adjustment too. I think she will hold fine, no signs of stress at all, but still pays to monitor something like this, would be a costly mistake if it came apart and bent that tube or the ends on it.

You're right, the dirt could care less what turns it, right behind that gravity wagon is his 620, bought new in '58, I had a chance to run it a bit, ain't been on a 2 popper since the B we had here when I was a kid in the 70's, He's fortunate to be able to have what he does, can't tell you how long he was dedicated to a sizeable milking operation + crops, probably never been out of the nearby areas for a lot of years, now he just does crops, some sileage trucking, 100 acres of hay and snow removal in the winter, he just took a few days to see the amish country in PA, we tried to plant a field tonight behind my 98 acres here, but t-storm rained us out, so he will take er easy tonight, been great to help him, and know yer appreciated, I've enjoyed the last few weeks to no end even with all the hard work and appreciate the help here, always something to learn especially when it comes to welding. Good luck out on your end, sounds like you have the same spring planting chaos going on too, well he's about 85 acres away from being done, if the weather holds he'll get that this week if we stay at it.