Bought A Used King Kutter 60" Tiller And It Broke.

[CH4Ohio]

Yea, KK got back to me and said they see this and it is usually related to an improperly adjusted slip clutch.
Can't deny that logic but I think this would have broke over time anyway.

What tiller to you like for a 5 footer?

I actually have a 5' King Kutter tiller that has been used HARD for almost 20 years. It'll jump when it hits a rock, but it does a great job and I couldn't be happier.

I'd suggest that you challenge them a little on this "weld". There's no way that KK can claim that it's properly welded and only broke because of improper slip-clutch adjustment. I'd push back hard on that and see if I couldn't get them to help me out with some parts to make that right.

Just my opinion . . .

 

[panamaguy]

Just got this tiller yesterday and started tilling with it today and it broke. Rotor stopped turning. Tiller had about 5-6 hours on it so very little use.
After pulling it apart I find that the splined shaft that is inserted and welded to the rotor shaft broke at the weld.
Inspecting it shows the weld had almost no penetration on the splined shaft and was doomed to fail. I have a feeling this has been an issue for them.

Hoping my welder friend can fix this up and I can get back to tilling.

View attachment 821842

As a licensed welder in Canada all my life tell your friend E7018 or E11018 DC rod. Preheat it and when finished it has to be cooled very slowly. Either a heat resistant blanket of in a box of floor dry or kitty litter. His biggest prolbem will be getting it dead straight. You might have to custom build a box if it is still mounted in place. Just cut up a cardboard box for this. I gather you are in the USA. Go to Harbour fright and see if they sell magnetic dial indicators or contact Little Machine Shop and order on. This is the only way you will get it dead nuts straight

 

[Camofurever1]

I had one of those tillers 20+ years ago. It tilled a lot of dirt in the 5 years I owned it Never had any issues with it. As far as I know, it is still going strong. I sold it with the JD 790 I had at the time. That definitely has not been welded correctly. If you don't have a welder with the capability to get the penetration needed for a strong weld, I would take it to a good welding shop. With a good weld, everything else should tear up on it, except for the weld.

 

[rlmnky]

I agree with everyone’s assessment of that weld. I can’t see how that could have gotten out of the factory. We all have brand preferences. For me, I just want equipment that gets the job done and doesn’t require constant maintenance. I have a 25+ year old KK on my tractor right now. It’s been used and abused. It’s hit rocks so hard that it jumped off the ground. It’s all original and the only maintenance it’s ever received is from a grease gun.

 

[bgr]

Looking at that weld, it is a machine weld, done with parts in a jig. The slip clutch tube slides over the toothed shaft and both are locked in place by a jig. An automated mig head then welds the joint as the jig rotates.

In this particular weld, the welder head location was slightly too far over the tube. The weld melted the tube without heating the shaft enough to bond with the weld. The error was probably 1/8 inch or less.

I wonder how many pieces they produced before their inspectors detected the problem? Apparently enough so the defective parts had gone to the factory floor and into production tillers. And they did not want to pull apart completed units to inspect the shaft and weld. Just sent them out to the customers and let them find the problem. Probably only 25% of customers have rocky soil, so 75% will never complain during the warranty claim period. That is a pretty good ratio in favor of King Kutter.

A mis set slip clutch should never be able to cause a failure like that. If that joint could fail with a slip clutch set too stiff, it should be redesigned. However, it did act as a type of shear pin for you. What would have broken if the weld had not failed? Make sure your slip clutch works.

A neighbor was tilling and jammed a big rock in the housing, locking the tiller solid. He had a rusted solid slip clutch. The parts which broke were the PTO drive gears in the tractor transmission. $4000. to replace them because the case had to be disassembled to replace the gears.

If Kuhn were sent a picture of a failure like that on any of their tillers, they would send a free replacement no matter how old the tiller.

 

[Bentrim]

Thats a weld?

Yeah the can was labeled Chicken S---.

 

[MRTOES]

From past comparison to Chinese mowers and other items to King Kutter I would bet you are dealing with a Chinese tiller with their name on it. That being said I would explore finding another shaft as I think this one came whole and has been snapped. Try various web sites before you give up.

 

[wirlybird]

As a licensed welder in Canada all my life tell your friend E7018 or E11018 DC rod. Preheat it and when finished it has to be cooled very slowly. Either a heat resistant blanket of in a box of floor dry or kitty litter. His biggest prolbem will be getting it dead straight. You might have to custom build a box if it is still mounted in place. Just cut up a cardboard box for this. I gather you are in the USA. Go to Harbour fright and see if they sell magnetic dial indicators or contact Little Machine Shop and order on. This is the only way you will get it dead nuts straight

Yea, my friend is a professional welder with decades of experience (oil & gas sector mainly) and he wasn't surprised by the crap weld. His friend who is a weld inspector was at the shop and said he was surprised it lasted that long (6 hours or so)!
We got it back together best we could but the weld will never break! We do have a slight wobble on the gear but it runs fine. Despite getting the shaft true the weld eventually pulled it slightly. I don't think it will bother anything and the fix was free!

 

[wirlybird]

From past comparison to Chinese mowers and other items to King Kutter I would bet you are dealing with a Chinese tiller with their name on it. That being said I would explore finding another shaft as I think this one came whole and has been snapped. Try various web sites before you give up.

Splined part is welded into the main rotor tube. Just a poor weld they let go.

 

[wirlybird]

Looking at that weld, it is a machine weld, done with parts in a jig. The slip clutch tube slides over the toothed shaft and both are locked in place by a jig. An automated mig head then welds the joint as the jig rotates.

In this particular weld, the welder head location was slightly too far over the tube. The weld melted the tube without heating the shaft enough to bond with the weld. The error was probably 1/8 inch or less.

I wonder how many pieces they produced before their inspectors detected the problem? Apparently enough so the defective parts had gone to the factory floor and into production tillers. And they did not want to pull apart completed units to inspect the shaft and weld. Just sent them out to the customers and let them find the problem. Probably only 25% of customers have rocky soil, so 75% will never complain during the warranty claim period. That is a pretty good ratio in favor of King Kutter.

A mis set slip clutch should never be able to cause a failure like that. If that joint could fail with a slip clutch set too stiff, it should be redesigned. However, it did act as a type of shear pin for you. What would have broken if the weld had not failed? Make sure your slip clutch works.

A neighbor was tilling and jammed a big rock in the housing, locking the tiller solid. He had a rusted solid slip clutch. The parts which broke were the PTO drive gears in the tractor transmission. $4000. to replace them because the case had to be disassembled to replace the gears.

If Kuhn were sent a picture of a failure like that on any of their tillers, they would send a free replacement no matter how old the tiller.

I didn't hit anything with it. A few bumps and bangs like you'd expect in hard soil but that was all and it stopped working about 30 minutes after I started using it.
Previous owner said he hit a little sandstone but said it barely even "flinched".
I am glad I only had to fix the tiller and not the tractor.
Slip clutch was in good condition but has been completely dismantled, cleaned, reassembled and tested. Running just slightly loose. Hit some roots after repair and I could see the tiller blades slow for a second so it is good I think. I can replace clutch discs!

 

[CliffordK]

From the looks of it, I'd say it was 5 or 6 VERY HARD HOURS....

Yeah, looking at the paint, it looks not much better than my 22 year old tiller that I’ve used annually.

The tines still have a lot of yellow paint on them, and from what I can see look relatively square, so the hours are low. Even fresh paint won't hide badly worn tines. The tiller has had some weather damage with more paint loss form rust than actual use.

EXACTLY. No heat discoloration on the parent metal and to obtain a huge weld bead like that, there would be. There is none. Not welded at all.

If painted, then wire brush cleaned, the discoloration would be gone.

How many Horsepower for that tractor/tiller? It looks pretty large.

That joint would naturally be a tough joint to weld. One of the reasons I started stick welding. MORE POWER!!!

First of all, the sleeve should be a very tight fit on the shaft, and everything should be very very straight. Any looseness of the sleeve, or wobble in the shaft would be a weak spot. Is it a through shaft, or just a stub?

However, the large shaft is a huge heat sink. One needs to push a lot of heat into the shaft, then just barely touch the weld to the sleeve to not burn it away.

If the back side of the flange is accessible, I'd probably also weld the back side of the flange to the shaft, and figure out how to shape the other parts to not grind away my weld.

Hopefully that tiller is designed to be repairable, and not just welded into one solid block.

 

[5030]

That joint would naturally be a tough joint to weld. One of the reasons I started stick welding. MORE POWER!!!

Maybe, maybe not. I own a Lincoln engine drive SMAW machine for field work but I much prefer my MIG with solid wire and shielding gas and at over 200 delivered amps, I routinely weld 1/2" thick material. Quicker, much less messy and no sticks needed.

 

[CliffordK]

The issue remains that it needs to be a tight fit of shaft into sleeve. I'd personally like a good press fit. And make sure you have good penetration into the shaft that takes significantly more heat than the sleeve.

A weld failure like that... a couple of days use... should be a warranty claim, but it is doubtful that it would be accepted due to the tiller likely being a couple of years old, and the multiple owners.

Nonetheless, a company needs the ability to track this type of problem. If failures become an issue, then they need to do random spot checks with stress testing components, monitoring new employees, and perhaps cutting welds for analysis.

Or they need a new design.

If you drive a RWD or 4X4 pickup, then the driveshaft should have a similar weld that takes hundreds of HP. However, it should be well balanced, and not subject to the impacts that a tiller takes. The larger the pickup, the larger the drive shaft.

 

[BigBlue1]

You must mean that you put 5-6 hours on it, not that the tiller only has a total of 5-6 hours on it? That thing looks like it is 10 years old.

 

[wirlybird]

You must mean that you put 5-6 hours on it, not that the tiller only has a total of 5-6 hours on it? That thing looks like it is 10 years old.

No, the tiller has 5-6 hours on it. It was purchased new, locally, last fall and I have the paperwork.
Seller showed me where he tilled with it this spring.
I put about 30 minutes on it before it broke.

 

[wirlybird]

The issue remains that it needs to be a tight fit of shaft into sleeve. I'd personally like a good press fit. And make sure you have good penetration into the shaft that takes significantly more heat than the sleeve.

A weld failure like that... a couple of days use... should be a warranty claim, but it is doubtful that it would be accepted due to the tiller likely being a couple of years old, and the multiple owners.

Nonetheless, a company needs the ability to track this type of problem. If failures become an issue, then they need to do random spot checks with stress testing components, monitoring new employees, and perhaps cutting welds for analysis.

Or they need a new design.

If you drive a RWD or 4X4 pickup, then the driveshaft should have a similar weld that takes hundreds of HP. However, it should be well balanced, and not subject to the impacts that a tiller takes. The larger the pickup, the larger the drive shaft.

They are aware of this happening and blame slip clutch adjustment.

 

[BigBlue1]

No, the tiller has 5-6 hours on it. It was purchased new, locally, last fall and I have the paperwork.
Seller showed me where he tilled with it this spring.
I put about 30 minutes on it before it broke.

Wow. I can't fathom how the thing has that much flaking paint and rust if it is less than a year old. Guess I don't store my equipment outside in the weather so I don't have a lot of experience with how fast it could deteriorate, but that looks like it would have taken much longer.

 

[ning]

Yea, my friend is a professional welder with decades of experience (oil & gas sector mainly) and he wasn't surprised by the crap weld. His friend who is a weld inspector was at the shop and said he was surprised it lasted that long (6 hours or so)!
We got it back together best we could but the weld will never break! We do have a slight wobble on the gear but it runs fine. Despite getting the shaft true the weld eventually pulled it slightly. I don't think it will bother anything and the fix was free!

Got pics of the repair?

 

[eddieirvine]

like the others posted if weld broke grind it out all of it and get down to the splined shaft then set up for a good penetration heat and weld it back up, wire welder or stick i like the wire welder the best