I broke my tilt ram *cry*

[Tazza]

A friend of ours got a pool dug today so we got the dirt that was removed. I had the job of moving the dirt that was left from the trucks. I moved quite alot of it then there was a CRACK and my bucket just sat there flopping around...... I thought i laid a pretty good weld around the rod where it attaches to the bobtach, it seems it wasn't good enough. I think the steel i welded the rod to was something strange as the weld tore off it, the weld didn't crack like i thought it would have done.
Not a great picture, but here is the bit i welded to the ram that looks like it was hardened or something with the look of the metal under the weld.

Warning, the following images may offend Bobcat lovers!
http://users.tpg.com.au/tazza_/ram/150_5001.jpg
http://users.tpg.com.au/tazza_/ram/150_5002.jpg
I'm glad its not a serious problem, its not not something i needed to happen, i still have a mountain of dirt i need to move.

 

[OldMachinist]

Did you replace the rod at sometime? And if yes what grade of steel did you make the new one from? Hydraulic cylinder shafting is normally chrome plated you have to chamfer the end you are going to weld large enough to make sure no chrome gets in the weld. If you made it from something else like like 1045TGP (turn, ground, polished)the higher carbon requires a slow cooling period after welding or the weld will be brittle.

 

[Tazza]

Did you replace the rod at sometime? And if yes what grade of steel did you make the new one from? Hydraulic cylinder shafting is normally chrome plated you have to chamfer the end you are going to weld large enough to make sure no chrome gets in the weld. If you made it from something else like like 1045TGP (turn, ground, polished)the higher carbon requires a slow cooling period after welding or the weld will be brittle.

I did replace the chome rod, i replaced it with centreless ground chrome bar.
I ground the end to a chistle point and built it up from there. The weld stuck perfectally to the chrome bar, but for some reason didn't stick to yoke at the other end..... It pulled the weld off it for some reason, like it was hardened or something. I may have used an odd grade of steel that i welded to the end or something.... I even used high penetration rods then finished with a good quality self leveling rod to *pretty* it up. I'm going to see a friend about it and get some mild steel, then i know its not a problem with the grade of steel.

 

[140mower]

I did replace the chome rod, i replaced it with centreless ground chrome bar.
I ground the end to a chistle point and built it up from there. The weld stuck perfectally to the chrome bar, but for some reason didn't stick to yoke at the other end..... It pulled the weld off it for some reason, like it was hardened or something. I may have used an odd grade of steel that i welded to the end or something.... I even used high penetration rods then finished with a good quality self leveling rod to *pretty* it up. I'm going to see a friend about it and get some mild steel, then i know its not a problem with the grade of steel.

Tazza,
Looks like you're running the same luck I am lately. At least it won't cost too much to fix, but a real bummer just the same.
When you replaced the shaft I take it you had a new yoke made up, was the old one not good enough to cut off and re-use?
Let us know how it works out and how you go about it. It's always good to see how others get to the nitty gritty of getting things done.
Don

 

[Tazza]

Tazza,
Looks like you're running the same luck I am lately. At least it won't cost too much to fix, but a real bummer just the same.
When you replaced the shaft I take it you had a new yoke made up, was the old one not good enough to cut off and re-use?
Let us know how it works out and how you go about it. It's always good to see how others get to the nitty gritty of getting things done.
Don

The old yoke was totally stuffed, the previous owner threw a 1 1/4" bolt through it without any lubrication.
I threw the old stick and yoke out, i bought a length of chrome bar that i machined down to size and cut the thread. I then made a new yoke with a hardened bushing that can actually be replaced!. I then welded it to the stick and presto! all was good, or so i thought......
I'm going to grind the stick into more of a point and turn the current up on my welder and give it another go. I saw a friend today and he said the steel is fine, you just need more herbs! Easy for him to say, he has a welder with 2-3 times more power than mine has!
Hopefully i will have a go at welding it tomorrow *fingers crossed*

 

[OldMachinist]

The old yoke was totally stuffed, the previous owner threw a 1 1/4" bolt through it without any lubrication.
I threw the old stick and yoke out, i bought a length of chrome bar that i machined down to size and cut the thread. I then made a new yoke with a hardened bushing that can actually be replaced!. I then welded it to the stick and presto! all was good, or so i thought......
I'm going to grind the stick into more of a point and turn the current up on my welder and give it another go. I saw a friend today and he said the steel is fine, you just need more herbs! Easy for him to say, he has a welder with 2-3 times more power than mine has!
Hopefully i will have a go at welding it tomorrow *fingers crossed*

I did a little research on the chrome bars availible here and found that they all are made from 1045-1050 grades of steel. I also read your old post about welding and quenching to keep the shaft cool. Quenching will hardened the welded area but hard is also means brittle. Here is what my steel suppliers book says about welding these grades of steel.
WELDABILITY—Due to higher carbon content, this material is not readily welded. With thin sections and flexible design, gas or arc welding may be used without preheating, but in joints over 1/2" to 3/4" thick preheating is necessary. To develop equivalent strength in a weld, a low alloy filler is recommended. Stress relieving after welding is also recommended.

I would recomend you take the rod out of the cylinder so you can preheat, weld and post heat it afterwards to keep the welded area from getting brittle and failing again.

 

[Tazza]

I did a little research on the chrome bars availible here and found that they all are made from 1045-1050 grades of steel. I also read your old post about welding and quenching to keep the shaft cool. Quenching will hardened the welded area but hard is also means brittle. Here is what my steel suppliers book says about welding these grades of steel.
WELDABILITY—Due to higher carbon content, this material is not readily welded. With thin sections and flexible design, gas or arc welding may be used without preheating, but in joints over 1/2" to 3/4" thick preheating is necessary. To develop equivalent strength in a weld, a low alloy filler is recommended. Stress relieving after welding is also recommended.

I would recomend you take the rod out of the cylinder so you can preheat, weld and post heat it afterwards to keep the welded area from getting brittle and failing again.

I found the problem.....
I had to chop out what was left of the mounting point wherre the ram meets the bobtach and weld a new one in, as the old one was so worn, i was sure i lined it all up before welding it in. It seems i was a little off, by a little i mean ALOT.
I put a piece of 1 1/4 bar through the bosses and measured about 30cm out from it. At that distance i'm out by around 10 mm!!!! from side to side, and about 3mm from top to bottom..... this is something i really didn't need...... I swear i checked this before i welded it in.
So... i'm going to have to chop out the mounting brackets i welded in and make a new set of the rotten things. I could get away with it if i just increase the clearance of the bushing but i think thats the wrong way to go about it, i'm going to have to get it rite and it should fix my problem once and for all.
This is really not a job i need, i have enough jobs to do as it is without having to fix something i stuffed up. Hopefully i can cut them out neat enough to be able to weld them back in.

 

[Luthor]

I found the problem.....
I had to chop out what was left of the mounting point wherre the ram meets the bobtach and weld a new one in, as the old one was so worn, i was sure i lined it all up before welding it in. It seems i was a little off, by a little i mean ALOT.
I put a piece of 1 1/4 bar through the bosses and measured about 30cm out from it. At that distance i'm out by around 10 mm!!!! from side to side, and about 3mm from top to bottom..... this is something i really didn't need...... I swear i checked this before i welded it in.
So... i'm going to have to chop out the mounting brackets i welded in and make a new set of the rotten things. I could get away with it if i just increase the clearance of the bushing but i think thats the wrong way to go about it, i'm going to have to get it rite and it should fix my problem once and for all.
This is really not a job i need, i have enough jobs to do as it is without having to fix something i stuffed up. Hopefully i can cut them out neat enough to be able to weld them back in.

Old machinist is right on the money about welding high carbon content steels at home without the right equipment. Grinding the shaft to a point is also not such a good idea, I would just leave it square and apply a good bead of weld around it.

 

[Tazza]

Old machinist is right on the money about welding high carbon content steels at home without the right equipment. Grinding the shaft to a point is also not such a good idea, I would just leave it square and apply a good bead of weld around it.

I don't know what the carbon content of the chrome bar i have is, but i do know when i cut a length with a metal abrasive saw the steel did have hard spots when i went to machine it.
I don't remember saying you should quench it as such, but i have used a wet rag and slowly run it down the bar to slowly cool it off., i prefer to just let it cool naturally, when you quench it as you said, it gets hard but it can also twist and crack welds.
I was told by a fitter and turner buddy of mine that i should grind the bar into a point so when you build it back up with weld it basically becomes one. He has done it this way on heavy earth moving equipment for many years.
I did the same weld on my 731 3 years ago and it still running strong, i didn't even grind it to a point. It must be because i stuffed up the mounting of the bosses.... I will hopefully get time to cut them out this afternoon, then i'll know if i will be able to get the rotten things back in without making a new set.

 

[Luthor]

I don't know what the carbon content of the chrome bar i have is, but i do know when i cut a length with a metal abrasive saw the steel did have hard spots when i went to machine it.
I don't remember saying you should quench it as such, but i have used a wet rag and slowly run it down the bar to slowly cool it off., i prefer to just let it cool naturally, when you quench it as you said, it gets hard but it can also twist and crack welds.
I was told by a fitter and turner buddy of mine that i should grind the bar into a point so when you build it back up with weld it basically becomes one. He has done it this way on heavy earth moving equipment for many years.
I did the same weld on my 731 3 years ago and it still running strong, i didn't even grind it to a point. It must be because i stuffed up the mounting of the bosses.... I will hopefully get time to cut them out this afternoon, then i'll know if i will be able to get the rotten things back in without making a new set.

Chrome bar sold here in Australia is the same specification as in USA , 1045/1050 which is a fairly high carbon content.

 

[Tazza]

Chrome bar sold here in Australia is the same specification as in USA , 1045/1050 which is a fairly high carbon content.

FIXED!!!
About a day and a half of work, but all seeems ok now. Cut the old mounting brackets out, made a new set and welded them in. Re-welded the boss on the end of the ram stick. I made sure i tack welded it all first, i made sure it wasn't twisting or cracking the welds before i did my final welding run.

 

[skidsteer.ca]

FIXED!!!
About a day and a half of work, but all seeems ok now. Cut the old mounting brackets out, made a new set and welded them in. Re-welded the boss on the end of the ram stick. I made sure i tack welded it all first, i made sure it wasn't twisting or cracking the welds before i did my final welding run.

Tazza
I usually weld extra (temporary) bracing on these to help minnimize the weld pulling the mounts out of alignment. Probably what happened? Anyway you will get her whipped into shape, a few bugs in the first hours of operation is common. I have been there way too many times...
Ken

 

[140mower]

FIXED!!!
About a day and a half of work, but all seeems ok now. Cut the old mounting brackets out, made a new set and welded them in. Re-welded the boss on the end of the ram stick. I made sure i tack welded it all first, i made sure it wasn't twisting or cracking the welds before i did my final welding run.

Good to hear you're up and running again, hopefully this will be the last fix you need for quite awhile. Out of curiosity, what did you use for steel plate for the brackets? Did you use the same thickness as factory or go thicker? I'm still trying to convince myself that I want to spend the money on the expander pin rather than making new mounts. It seems I have caviar ideas and a peanut butter and jelly budget.

Don

 

[Tazza]

Good to hear you're up and running again, hopefully this will be the last fix you need for quite awhile. Out of curiosity, what did you use for steel plate for the brackets? Did you use the same thickness as factory or go thicker? I'm still trying to convince myself that I want to spend the money on the expander pin rather than making new mounts. It seems I have caviar ideas and a peanut butter and jelly budget.
Don

Ken, yeah i did zap 2 temp. brackets to the bobtach to keep it all square. I used a length of 1 1/4 bar so i could measure it all so it was tracking straight. I'm really not sure if the weld moved it that far first time around or not, it seemed like a awfull lot to move. I think i'll jusy say it was so i can't blame myself for not checking it
I'm not sure what the origional thickness of the steel was, so i used 1/2" plate for the job. It seems more than strong enough. I just cut it to shape in a band saw then tack welded the 2 plates together and drilled a 1" hole through the middle. It then needed to go in the 4 jaw chuck in the lathe to bore it out to 1 1/2". You can skip the lathe bit if your drill can handle drilling a 1 1/2" hole.