Removing broken hitch ball?

Keep trying. You may be funny on purpose, some day. ;-)

The ball itself doesn't turn while I'm rotating the nut.

Because I'm curious what happened to the threads (and if it was indeed the nut that failed), I think I will slice the nut off and pop the ball out of the bumper.

--Winston

Ooooo! I *like* that! Thanks Jim!

--Winston

lockwasher with a chisel.

It would, but that leaves me with the ball and nut unsupported in the bumper. I'd have to come up with something to clamp the ball in place so I could drill or slice into the nut and/or mounting stud. I now have adequate clearance for my Mototool after I drill the nut axially as per Jim Wilkins' suggestion.

That'll be my plan.

--Winston

I agree that slicing the nut and stud off would "Git 'er done" quickly.

I really like Jim Wilkins' idea of drilling axial holes in the nut to weaken it then attack it with the Mototool. That gives me a couple sections of nut and an intact stud so I can satisfy my morbid curiosity about why the fastener failed so miserably under "weak old man" torque. :)

--Winston

If I'm gonna get HF quality, I want to pay HF prices.

(...)

Many server errors with tinyurl this morning. I get the idear however.

I've got a couple angle grinders and a brand new pack of cutting discs, so I'm set, if I decide to go all Medieval on it.

Holey Underwear!

Okayfine. Thanks!

--Winston

That'd damage the economically designed bumper, methinks.

I've become curious what failed and why, so I'll do my best to separate the fasteners whilst leaving as much evidence in place as possible. When I run out of patience, I'll just slice the nut and stud off from behind and do some artful cutting to free the remaining bits.

Thanks everybody! Your suggestions are valuable and thought- provoking.

--Winston

"And remember folks, the more you drink, the funnier I am!"

(That is all I remember from his routine.)

--Winston

Just a thought....If there's enough room there and you could borrow a large enough nut splitter the job would almost do itself:

I've had a couple of sizes of nut splitters in my "hell box" for 30+ years and every so often one comes in handy.

Jeff

Yeah, I use one, too. It was a regular maintenance tool on my '78 Ford Fiesta, which had special anti-nut-loosening features that involved rusting the nuts in place if you looked at them cross-eyed. It was like ultraviolet-cure adhesive, but you could do it with your naked eyes; faster if you have X-ray vision.

Anyway, I had to sharpen mine from time to time (even to finishing with a hard Arkansas stone) because I used it to crack some pretty hard nuts with it. In Winnie's case, I wondered about finding one large enough and also about how hard that nut may be.

It sounds like it's junk, so maybe a nut splitter is the trick.

So, you're going to give your bumper an Orchiectomy?

Me too... luckily haven't needed one for some years now, but it's nice to know they're there.

Erik

You know, now that I think about it, years ago I remember seeing the local trailer rental place cutting off such a nut... they were using a big 'porta power' like nut splitter... the biggest I've (personally) ever seen.

Wonder if it's a common issue for those outfits, and if so, would they cut off yours for a few bucks. Might be worth some calls.

Erik

I agree that would have come in handy. It would had to have been a very large tool for a 3/4" dia. thread, as Ed says.

I looked it over and decided that I could slice through the middle of the nut flats with some Dremel discs. (It took 5 discs, one shattered).

After slicing through two opposing flats and attacking the gaps with a chisel, I managed to split the nut into two semicircles and free the hitch ball without damaging the bumper.

The autopsy shows the nut thread and the stud thread look surprisingly intact. The plating on the stud is down into the copper for the length of the nut on both walls of the thread and the crown of the thread is much shinier and flattened in relation to the crown of the non-stressed part of the stud.

The minor diameter of the nut is flattened for about

100 degrees and much sharper for ~260 degrees

This is supposed to be a 3/4-16 thread.

So the major thread of the stud should be no less than 0.75" dia. It measures 0.744". The nut is no longer with us as such but it appears that the minor diameter of the nut widened and began slipping over successive crowns of the major diameter of the stud.

I measured the thread on the replacement ball and found the major diameter of the stud to be 0.743" instead of 0.75". The minor diameter of the nut should measure no more than 0.6823". The new nut measures 0.689" I.D.! So our fasteners appear to be sloppy to the tune of about 0.007" per side!

The tightening specification is 160 ft. lbs. I don't know how much force I was applying to the nut but I would be very much surprised to learn it was much over ~40 ft. lbs when the fasteners failed, given the short lever arm of the ratchet and the remaining muscle tone of a weak old man. :)

Given that the thread on the replacement ball appears to be even sloppier than the thread of the ball from O'Reilly Auto, I will assume that it will fail at somewhat lower torque than did the O'Reilly part.

I conclude that Ed is right.

These parts are junk.

Thanks for your patience and advice.

:)

--Winston

Our posts passed in the night!

The old hitch ball is off through the use of Dremel and chisel. The new hitch ball appears to be of even lower quality than the old one was.

Now I am in 'ponder' mode. :)

--Winston

put a dollup of anti-sieze on the threads

Sounds like I should 'plate up' the stud by a few thousandths first. I really don't see this thing handling anywhere near the 160 ft. lb. torque spec as is.

Anyway, thanks for your thoughts.

--Winston

OMG, you're -not- going to use the replacement, which is also out of tolerance, are you?

I think I usually try to get half a turn after compression of the lock washer, if memory serves. (snug + oomph) And check it every time before each of the first few trips.

-- Energy and persistence alter all things. --Benjamin Franklin

I dunno where your parts originated, but over the years, I've found a lot of mating threaded parts from China or India to be completely unsatisfactory.

You were probably fortunate that you had the threads let go at low torque, as I suspect that failure was a predetermined fate. Roadway use of trailers can produce some harsh shock loads, so it's better to have the parts fail before use IMO.

It seems retailers will stock anything that has a decent profit margin, now a'days.

When I examine new parts, I find threads which exhibit so much free movement that the parts aren't suitable for any purpose I can think of.

When machine parts have oversize female threads, I'll see if I can retap to a slightly larger fastener, even if the fastener may need to jump from metric to inch or verse visa. Loctite and other "fixes" are often a poor choice where there isn't enough engagement of the threads.

I don't know what the popular overseas methods are for making threads in holes, but I do know that taps don't grow as they wear.

Poor axial alignment is another issue that puzzles me. I could only tap a hole that far off if I was attempting to run a tap by hand, behind my back. Since these overseas manufacturers don't reject parts due to poor quality, it's up to the end user to make the right decision wrt proper/safe use of those parts.