Bent lift arm

muckymanor

Well-Known Member
The old man got the tractor and tanker sunk in a boghole last week (well the tractor went down and the tanker stayed afloat). He got a neighbour to pull him out. The lift arms were buried in the ground, so he raised them. The neighbour swung him to try to get him out of the home and the lift arm caught on the tanker drawbar and bent it well. To make matters worse, they couldn't get it out that way (they didn't notice that the lift arm against the drawbar was stopping them from turning, so they swung it the opposite way and slightly bent it too.

Would someone press a lift arm straight and would it be safe to do so? Or should we be looking at getting replacement ones? I have priced a second hand pair and it ain't pretty!!!!
 
The old man got the tractor and tanker sunk in a boghole last week (well the tractor went down and the tanker stayed afloat). He got a neighbour to pull him out. The lift arms were buried in the ground, so he raised them. The neighbour swung him to try to get him out of the home and the lift arm caught on the tanker drawbar and bent it well. To make matters worse, they couldn't get it out that way (they didn't notice that the lift arm against the drawbar was stopping them from turning, so they swung it the opposite way and slightly bent it too.

Would someone press a lift arm straight and would it be safe to do so? Or should we be looking at getting replacement ones? I have priced a second hand pair and it ain't pretty!!!!
How bent is it .
 
Its rare to see a lift arm bending , they usually snap . And i imagine would snap if you try to straighten it back .
I welded Dexta lift arms years ago , and used 1/2 thick x 2 1/2 inch angle from a scrap machine as reinforcement underneath.

As stated above , it really depends what you want to carry with it , and where.
Transport box or a bale of silo, on your own land , weld it or straighten it .
2 bales , a fert spreader with 1 ton on a public road , I think you know what answer is.
A spreader, mower , sprayer or topper won't be worth much after collapsing on the road at 35 kmh. Not to mention the damage caused to another vehicle following behind you.
 
Depends what sort of lift arms, what tractor it was on and what it will he carrying

Trying to fix it is a double edged sword. It wont go back itself, in engineering terms the material has yielded. If you bend a piece of metal without reaching whats known as the yield point, it will spring back because the bonds between the molecules havent been broken. This is called elastic deformation

Whats happened the lift arm is the bonds have broke and new bonds reformed. It wont revert to its original form without intervention. This is called plastic deformation.

No matter what technique is used to straighten it, by and large it will be weaker. Dont do it cold, or it could end up my side of the Shannon. If you have access to gas do it hot. When you heat metal though, it will effect the temper because the heat will change the structure of the material, bringing the carbon to the surface and it will end up brittle. If you hit a bump in the road, it may not be able to give enough to take the shock and break.

The solution to this is to slow the rate at which the metal cools. This can be done by immersing the metal in sand after heating it.

The issue is trying to heat it, straighten it, and get it in sand wont be easy.

If its on something like a 35 carrying a transport box, go for it.

If its a new tractor carrying a mower or a hedgecutter, new Lift arms would be pocket change compared to the damage that would be sustained if it broke.

Thats just some guidance on the situation, but i think you'll have to make a decision on this yourself.
 
How bent is it .

Christ mucky answer the questions instead of giving the lads blue thumbs, or you just might get the 2 fingers. !!

Sorry, I was in a meeting this last while and it wouldn't look good me replying to posts on here in the middle of it.

Left one bent to approximately 25 degrees from straight and right one to approximately 10 degrees.
 
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Depends what sort of lift arms, what tractor it was on and what it will he carrying

Trying to fix it is a double edged sword. It wont go back itself, in engineering terms the material has yielded. If you bend a piece of metal without reaching whats known as the yield point, it will spring back because the bonds between the molecules havent been broken. This is called elastic deformation

Whats happened the lift arm is the bonds have broke and new bonds reformed. It wont revert to its original form without intervention. This is called plastic deformation.

No matter what technique is used to straighten it, by and large it will be weaker. Dont do it cold, or it could end up my side of the Shannon. If you have access to gas do it hot. When you heat metal though, it will effect the temper because the heat will change the structure of the material, bringing the carbon to the surface and it will end up brittle. If you hit a bump in the road, it may not be able to give enough to take the shock and break.

The solution to this is to slow the rate at which the metal cools. This can be done by immersing the metal in sand after heating it.

The issue is trying to heat it, straighten it, and get it in sand wont be easy.

If its on something like a 35 carrying a transport box, go for it.

If its a new tractor carrying a mower or a hedgecutter, new Lift arms would be pocket change compared to the damage that would be sustained if it broke.

Thats just some guidance on the situation, but i think you'll have to make a decision on this yourself.


Will get it pressed and see how it turns out. Don't think it would be good to heat it. If it straightens in the press, we will consider it, if not, then we'll have to invest. It should straighten - it appears to be quite flexible.
 
Sorry, I was in a meeting this last while and it wouldn't look good me replying to posts on here in the middle of it.

Left one bent to approximately 25 degrees from straight and right one to approximately 10 degrees.
Definitely worth trying to straighten them . But with out heat I doubt the 25deg bent one would straighten without cracking. Remember the steel has stretched when it bent . So when your pressing it you’ll be trying to stretch one side and shrink the otherside of the arm . Heat is your friend in that situation. In the hands of the right man they should get them near perfect I’d say .
 
For the sake of 500 I'd go away and buy them even tho it's sore I know.
It's alot better than something falling off the back on the road.
If it was mine it would always be in the back of my head will something happen.
I'm thinking the same, hedge cutter or double bale carrier wud put serious pressure on already week arms.
 
The arm on the mxu here had a very slight bend in it and I noticed a crack below the first hole for the drop arm pin, we got it pressed straight cold, V-ed out the crack nearly full depth a couple of passes of weld grinded it flat and added about 14” of 1” pin steel long under the arm.
Worked out fine it has a share of work done since. But it was only a very slight bend as in 5deg and there was a bit of work getting it dead straight again, it’s like spring steel. I don’t think I’d have chanced it if it was much worse but new was big bucks and there weren’t many broken at the time.
 
I don't know if he is way off the ball or not till I go to the NH dealer, but the scrapper that I spoke to wants 500 sterling for the pair!

keep trying around, whats the make and model of tractor, never know someone here might know one scraped. too dangerous a item to go doing a handy way out. Chalk it down to something you can do with you get to your senior years. I cant wait until I then have a licence to make complete balls of things
 
The old man got the tractor and tanker sunk in a boghole last week (well the tractor went down and the tanker stayed afloat). He got a neighbour to pull him out. The lift arms were buried in the ground, so he raised them. The neighbour swung him to try to get him out of the home and the lift arm caught on the tanker drawbar and bent it well. To make matters worse, they couldn't get it out that way (they didn't notice that the lift arm against the drawbar was stopping them from turning, so they swung it the opposite way and slightly bent it too.

Would someone press a lift arm straight and would it be safe to do so? Or should we be looking at getting replacement ones? I have priced a second hand pair and it ain't pretty!!!!
I know it's not funny but can't help thinking about a lad capable of bending a crowbar in a bog.. the bend is probably concentrated where the stabiliser hole or drop arm hole is so further weakening the weakest part, safest bet is to put on an undamaged set.
 
I have welded one on a TM125 5 or 6 years ago. Reinforced it with a bit of 15mm plate underneath, never a problem with them since. I even had to weld it without talking it off because the pin in front was seized.
 
It is the usual thing unfortunately ... all fine until something goes wrong.

If a big enough incident the metallurgist will be wheeled in and then when the questions come about design assessments, heat treatments etc. what analysis was undertaken to determine suitability to repair and basis of repair etc etc.

I know it’s not what you want to hear but it’s the nature of these things nowadays.
 
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