New forum member here, question on repair of lower a-arm taper

[modot66]

hi everyone, have a project i was looking for help/tips/guidance on. my older off road UTV (never street driven) has been eating ball joints and i think i found the culprit. on one of the rides the castle nut on the ball joint fell off which allowed the ball joint to open up the tapered hole in the a-arm (see pic).

has anyone ever had to repair anything like this?

the a-arm was custom made by a company that is no longer in business so i am trying to fix this one. i can tig, mig, and stick but do not have access to a lathe or mill. my thoughts were to tig weld and build the walls up, then taper ream it back to original dimensions. i have also seen weld-in taper sleeves but am not sure my drill press chuck could handle drilling the a-arm out to accept the sleeve.

any ideas or tips? i think the taper on the ball joint is a 7 degree taper based on my rough measurements. if anyone has tips on how to measure taper too i would be grateful.

 

[Scottl]

My advice:

Find a shop to bore it out for you and use the weld-in taper sleeve.

 

[JohnEvans]

From the looks of that A arm more like a complete new one would be in order. But as above weld in a repair taper sleeve. Fabricated piece with broken welds Sheesh !

 

[LKeithR]

My advice:

Find a shop to bore it out for you and use the weld-in taper sleeve.

Since those holes are wallowed out so much that's probably the best idea for fixing this. Years ago we used to do
a lot of custom automotive work and we had a number of reamers ground up for making new parts and also doing
repairs. The taper is 1-1/2"-12" included angle which works out to 7.125 degrees.

If you can build the holes up and find a reamer it's an easy fix but if you don't have access to a reamer the inserts
are a good second choice.

If you want to do it "farmer style" you can build up the hole, drill it out to the appropriate size and use the spud from
a disassembled tie-rod end to form the taper. Heat the area around the hole till it's red hot and use a big hammer
to drive the spud of the tie rod into the hole. It will create a taper that is more than adequate for most situations.
We usually took the spud from the tie rod end and welded it to a chunk of solid round stock to create a punch that
was easier to handle...

 

[modot66]

From the looks of that A arm more like a complete new one would be in order. But as above weld in a repair taper sleeve. Fabricated piece with broken welds Sheesh !

trust me i would love a new arm, but the company that made these has been out of business for a few years

 

[modot66]

any tips on how to measure taper? i measured the big and small end then measured the distance between the two and put into a taper calculator. i wasn't able to be accurate enough as after measuring twice i came up with a 1.3"-12" and then a 1.9"-12" taper. if i could find the right taper then building it up and reaming it out would be my first choice.

i like the idea too of farmer style!

my other option is to just weld the ball joint in then if i ever have to replace the ball joint grind it out.

Since those holes are wallowed out so much that's probably the best idea for fixing this. Years ago we used to do
a lot of custom automotive work and we had a number of reamers ground up for making new parts and also doing
repairs. The taper is 1-1/2"-12" included angle which works out to 7.125 degrees.

If you can build the holes up and find a reamer it's an easy fix but if you don't have access to a reamer the inserts
are a good second choice.

If you want to do it "farmer style" you can build up the hole, drill it out to the appropriate size and use the spud from
a disassembled tie-rod end to form the taper. Heat the area around the hole till it's red hot and use a big hammer
to drive the spud of the tie rod into the hole. It will create a taper that is more than adequate for most situations.
We usually took the spud from the tie rod end and welded it to a chunk of solid round stock to create a punch that
was easier to handle...

 

[cyanidekid]

I wouldn't weld on the balljoint itself as that will take the temper out of the steel, or worse yet, embrittle it. either way, you are creating a "break here" situation, and asking for a catastrophic failure. not saying it couldn't be done safely, but NO, just don't do it, its a really bad idea!