8 replies to this topic

[jdcrawler]

What the heck is going here ?????

Yesterday I had the mower on the tractor in the raised position when I left the shop for the night.
This morning I went into the garage and saw that the lift arm had broken loose from the tool bar brackets.




I've never had any schooling or proper training in welding so I don't know all the fancy formulas for how much heat to use and how fast to set the wire speed.
But I have been welding for a very long time and I have never had anything like this happen before.

The weld itself has separated from the square tube brackets.
You can see that the weld is consistent and doesn't have any air pockets in it.




Here you can see that the weld etched down into the surface of the square tubes and when the lift bar broke away it took that part of the square tube metal with it.
These square tubes are not cast iron but they are some sort of cast steel or something ?




Anyhow .. I clamped the lift bar brackets back on the square tubes and re-welded them.
I really burned the weld down into the metal this time.

Then I drilled holes thru the brackets and the square tube and tapped them out for 3/8-16 threads.
The brackets are counter bored with 3/8 diameter clearance holes.




The brackets are then bolted down with bolts and lock washers to make sure they stay in place this time.




Just to play it safe, I put flathead counter sunk screws in the foot pads also.
These are now ready to paint and re-mount on the tractor.

[Lauber1]

Kind of looks like a cold lap weld. You probally should have used a stick welder with 7018 rod. You see this in a lot of the steel made in the 50's, where for some reason its hard to get the weld to penatrate with out a lot of heat.

[Ryan313]

I think somebody sabotaged it! Sorry that broke on you, I don't have enough welding knowledge to help much. Im glad you fixed it, I don't think it will come loose with those bolts!

[wvbuzzmaster]

Fine repair Ray. Good thing it happened while it was parked. If you had been driving around it would have torn up the mower and your bracketry.

[caseguy]

Any kind of cast is harder to weld than formed steel. The crystal structure of cast is kind of random whereas the crystals in a piece of rolled or forged steel have been aligned by repeated heating and cooling cycles as well as the forging process. The bolts were a great idea and a perfect little bit of insurance!

[wilberj]

The tubes could be a much harder steel like a 4140, D2, or 8620 that are tool steels.
Being harder the weld will look to bern into the softer angal iron but will not bern into the much harder alloy steel.

[KennyP]

I don't think they will come loose anytime soon, Ray. Sorry you had the re do, but much sturdier now.

[mjodrey]

You must have had gremlins come in over night and have a little fun. Nice fix on it though,with the bolts.

[achomesteader]

If you have gremlins hiding in your shop, nothing is safe. You need an exterminator. You did a good job correcting their mischief though.

Edited by achomesteader, March 13, 2012 - 05:03 AM.