Welding a tie rod

[gwdixon]

Motivated by another thread on TBN, how would one go about welding this tie rod attachment point back together?

View attachment 275674

Is replacement the preferred option?

 

[Shield Arc]

I'd go for replacement first. Second would be to braze it.

 

[Soundguy]

as much as I like to cobble and fix things.. I'd agree.. repalce first. if I had to field fix I'd buzz it then repalce once I got it home..

 

[Paul N]

I agree with the other replies. For your own personal safety, just replace it.

 

[cowski]

if it was mine and it is cast steel i would weld it with 7018.if it is cast iron buy it.to weld it i would v it out then use 1/8 7018 .make a pass on each side then peen it .let it cool a few hours repeat .then take a washer and weld it on the bottom for support.

 

[weldermike]

as much as I like to cobble and fix things.. I'd agree.. repalce first. if I had to field fix I'd buzz it then repalce once I got it home..

X2 on that. Wouldnt want a failure with a full loader. I would play it safe and replace it.

 

[flusher]

Braze it.

 

[kcender]

Motivated by another thread on TBN, how would one go about welding this tie rod attachment point back together?

View attachment 275674

Is replacement the preferred option?

I am thinking I was involved in that thread but as far as welding that part I would price a new one and then decide if it was worth trying to weld it.The first thing in welding is to determine which material it is,either cast iron or cast steel.A spark test is usually quite accurate for this.At work we have a machine that will give you the exact chemical analysis of any metal but most people don't have access to this.If the sparks are cherry red it is usually cast iron,if orange then cast steel.As far as how I would weld it the process is very similar,just a bit more care is required with cast iron.First the part would have to be meticulously cleaned.Next I would put a few very small tacks,just enough to hold the pieces together.Then preheat with a torch but not very much,maybe 150 F.The process I use at work would be TIG welding with a Certanium 423T rod.Obviously the joint will have to be bevelled and welded intermittantly from side to side.Depending on the heat input and how long it takes to weld it,I may play the torch over it to keep the heat input uniform.After welding is complete I would run the torch over the part to spread the heat out uniformly and wrap it in a piece of fire retardant cloth and let cool over night.I should add that if I didn't think the weld was going properly I would have stopped at that point and realized it would not be a sound weld.There are various ways to weld cast pieces but this is a method that has worked for me.Experience will let me decide if I think the welded part should be put in service or not,it is a judgement call.I will say it will be hard to get 100 percent penetration in the joint without getting burnthrough to the inside so this will compromise the welded area somewhat.Probably not as easy as it may look at first,I guess the cost of a new part would have a lot to do with the decision of repair or replace.After writing this I took another look at the photo. Hard to tell but it looks like it would be hard to get at one side of the joint because of the way it is made.The weld would have to go from the sides inward,not top to bottom if I am making myself clear.Because of the shape of the part it may be hard to get a grinder or torch at that side without doing damage outside the weld area.As I said things are never as easy as they may appear.

 

[gwdixon]

Great advice from all. Thanks guys.

I'll put a link to this thread on the related post. (Here it is: http://www.tractorbynet.com/forums/kubota-owning-operating/253446-bx-broken-front-axle.html

Yes, ksender, you replied to the original post on the Kubota forum. Not that your expertise was being question. I was looking for more support for the OP.

BTW, the L3650 shown in the photo had the casting replaced at a dealer for $1000.

 

[kcender]

Just trying to help.

 

[gwdixon]

Just trying to help.

And help you did - thanks again.

This is yet another example of why TBN is such a productive and useful resource.

 

[Gary Fowler]

I would bet that the part is cast steel as I dont think cast iron would hold up to well in that application. It looks like replacement will cost some big bucks as it appears that the entire hub will need to be replaced. I would V bevel it top and bottom, weld a pass from each side using 3/32" E 7018 electrodes. Pre-heat it to 250F and then weld a pass from each side with continuous welding, dont stop and let it cool and the start again as this will just induce more hardness and stress into the weld each time you cool it off. You could peen it a pit when removing the slag with the pointed end of the chipping hammer or use a needle scaler. The welding I dont think will be a problem, but getting full pen or partial pen weld without messing up the taper bore is going to be impossible so plan to have the hole re-bored. Check with a machine shop to see if they can do it. If so, it might be easier to just weld the hole up solid and then taper bore it for a perfect fit. It will be impossible to keep it perfectly square so the taper bolt fits back in without stressing the connection. By welding up the hole along with the broken area, you will have a stronger connection. I am afraid that means disassembling the whole front axle housing but you would have to do that anyway for replacement. After I got it all welded up, I would let it set for a day to make sure you dont have and delayed stress cracking. If it doesnt crack then it will be good to go to the shop for machining.
Just curious, how did you manage to break that tie rod connection?

 

[Shield Arc]

Just curious, how did you manage to break that tie rod connection?

If I remember correctly, Kubota places the steering cylinder and tie rods in front of the axle, makes it so easy to run into things! One of the reasons I didn't buy a Kubota, that and the pedal configuration for the hydrostatic tractors.

 

[gwdixon]

Just curious, how did you manage to break that tie rod connection?

The L3650 was mine for about 20 years or so. Sold it to a neighbor (inexperienced tractor owner) and he burned up the clutch as well as breaking the tie rod mount as shown. When I asked him what happened he said that the involved wheel sunk in next to a stump and he was cranking the steering wheel back and forth to get the wheel loose. Oh, well.

Shield Arc is correct. The tie rods are forward of the axle housing and just sitting out there waiting for a hit.

 

[Shield Arc]

If it is in deed cast steel, I've had amazing luck welding cast steel pile driving equipment with just 7018, also used 312 stainless steel, and Super Missile Weld, (same thing as 312 stainless steel just cost a lot more) Little pre-heat, and very slow cool down.

 

[Gary Fowler]

Might be good "experience" for the new owner to fork over the money to replace the axle housing as a reminder to not be so stupid next time.

 

[Soundguy]

i agree.. if it is cast steel.. it 'should'
weld ok. I've welded both cast steel and iron on old tractors. as has been said.. CI just takes more time and process is different a bit.

if it costs an arm and a leg.. then I'd try to fix it aft disassembly and cleaning. if it's cheap.. I'd repalce it.

good luck

 

[Baby Grand]

Gary is right - you'll have to remachine that tapered bore after welding because it will distort from the heat. Even if you do, that taper is going to exert a "hoop stress" right at the welds when you reassemble everything, plus it's in an area or reduced cross section. Even if you do a faultless welding job, I'd give it high odds of failing, again, near the weld - where the heat affected zone transitions into the base metal. Another way to approach it would be to find something in a scrap yard with a similar tie rod end geometry. Cut that piece off, away from the tapered bore and weld that onto the housing after cutting the housing down to fit. Then the weld won't be right in the highly loaded area of the lever. You'll still have to do a major disassembly, but that's in the cards anyway. Just my $.02.

 

[cowski]

old ih and whites had tie rods in the front.it gets aggravating when you hit trees.you have had several good recommendations on welding cast steel from gary fowler and kecender .certanium rods are excellent ,i use and highly recommend them.i do not think i would braze it.in this case i would weld it on the tractor with 7018 ,when you v the crack out leave the last 1/8 or so undisturbed.clamp it then tack it good.weld one pass on each side then peen it, let it cool. then repeat until filled. the tie rod end should still fit the hole and the seals should not be melted out.a washer could be welded to the bottom for support.good luck

 

[ruffdog]

Once you get the part off the tractor, have your machinist look at the part BEFORE it is welded (with both pieces)so he can make a drawing of hole location, hole angle, taper angle, taper depth, ect. That way he doesn't have to start from scratch..... He might have to order the correct taper reamer.