Left Nut Is Missing!

Actually, it's a left-handed--or reverse-thread--jam nut that should be on the tie rod that connects the tillers on our two rudders. And it's not really missing;it was never installed. It's needed to take up some minor slop between one of the threaded bronze forks that screws on to the tie rod end. We found a jam nut for the end with right handed threads . . . and it works perfectly . . . but I'm starting to think a reverse thread nut in this size (3/4-14)may not exist.

I've tried McMaster Carr, Fastenal and several online outlets with no luck. My last recourse is to have one made unless someone has a good source for obscure hardware.

Have you used a thread pitch gauge to make sure that it's 14 threads per inch?

3/4" is normally 16 threads per inch.

or contact adam and have him make one for you.

Thanks for the PM and link to Adam. I'll check him out.

I've seen 3/4-16 and 3/4-10 nuts for sale, but the maintenance supe at the yard put a gauge on the reverse threads and they're 14. This is on a 3 foot long pipe that appears to have NPT threads so it would be tough to send it to anyone.

Oddly, a 3/4" through hull nut fits the right hand threads on the other end of the pipe. I'm also wondering if this could be metric.

Could it be a left handed straight pipe thread ?

Many hardware stores have specialty boxes in the fastener department (generally Hillman brand) and I know left hand thread nuts is one they may or may not choose to include in their offering. Take the time to look; they may not even know they have it.

Taps

Google left hand strait pipe taps. Looks like several vendors have availability.

So this tie rod connects the two rudders to each other?
Can it just adjust from one side, leaving the other side fixed? As in take fork end off of rudder arm and adjust then reattach to rudder arm. That way you could epoxy the side for which you have no jam nut.

This would be half turns for the fork, is that a fine enough adjustment?

I have the sense mine is this way. But uses a np straight standard hand thread on both ends. And one end is spun with a jam nut on one side to move rudders in or out. And the other is tight on the fork, like a bolt into a nut.

Lots of left hand nuts here:
https://www.fastenal.com/home

sdowney717 said:

So this tie rod connects the two rudders to each other?
Can it just adjust from one side, leaving the other side fixed? As in take fork end off of rudder arm and adjust then reattach to rudder arm. That way you could epoxy the side for which you have no jam nut.

This would be half turns for the fork, is that a fine enough adjustment?

I have the sense mine is this way. But uses a np straight standard hand thread on both ends. And one end is spun with a jam nut on one side to move rudders in or out. And the other is tight on the fork, like a bolt into a nut.

Click to expand...

Putting epoxy on it would be a bit too permanent...

Some clevises have a split sawn in threaded part with a pinch bolt so you get it where you want it and tighten the pinch bolt on the clevis to clamp it where you want it, with no play left.

The other way is a jam nut. Not having a jam nut means the hydraulics pulling and pulling on the clevis will eventually wear out the threads requiring a new clevis and jam nut.

Probably, one end is right hand thread, and the other is left hand thread so when the jam nuts are loose you can twist the shaft and lengthen or shorten it without removing either end clevis. That's why one end appears to be 'normal' and the other left hand thread.

stubones99 said:

Putting epoxy on it would be a bit too permanent...

Some clevises have a split sawn in threaded part with a pinch bolt so you get it where you want it and tighten the pinch bolt on the clevis to clamp it where you want it, with no play left.

The other way is a jam nut. Not having a jam nut means the hydraulics pulling and pulling on the clevis will eventually wear out the threads requiring a new clevis and jam nut.

Click to expand...

Heat up the joint with a propane torch, the epoxy will melt. My suggestion was make one side permanently fixed and adjust from the other side.

Thanks for the ideas. I think immobilizing one end will be a solution of last resort. I tried Fastenal, but they don't have it. I'm going to remeaure the right hand threads to see if they're the same pitch as the left.

Angus: You are correct, the "right"way to do the job is with a new nut of correct rotation and pitch. The quick/lazy option usually comes back to haunt you.

Making a nut to a customer's specs is something any small machine shop can do. Probably give it to the apprentice. Perhaps you could try a school or college workshop?

Shoalwaters said:

Angus: You are correct, the "right"way to do the job is with a new nut of correct rotation and pitch. The quick/lazy option usually comes back to haunt you.

Making a nut to a customer's specs is something any small machine shop can do. Probably give it to the apprentice. Perhaps you could try a school or college workshop?

Click to expand...

This makes the most sense to me. I can just take the tie rod to a shop and have them build me one vs. spending any more time searching . . . plus risking trial and error. Thanks again, all.

BTW: You should really win a prize for most eye-catching post title!

I saw the post title and just had to read the whole thing (my first reaction: check your left boot)

In the picture you posted is the link bar clevis on the left (the square one) or is it the rod on the right (with the "heim joint")?

Greetings,
Welcome aboard. Good argument for wearing boots as long as your pant cuffs are tucked in...

Shoalwaters said:

BTW: You should really win a prize for most eye-catching post title!

Click to expand...

Thanks. I used to write headlines for a newspaper and the goal was to catch the reader's attention (back when people read) . Old habits die hard.

Frankt said:

I saw the post title and just had to read the whole thing (my first reaction: check your left boot)

In the picture you posted is the link bar clevis on the left (the square one) or is it the rod on the right (with the "heim joint")?

Click to expand...

The tie bar I'm trying to fit is on the left.

Your boat was built in Asia, are you sure it's not metric?

I was looking at that clevis and noticed that there is a cotter pin through it, usually those holes are there so that you can shine a light through and verify that there is enough thread engagement to prevent several things, including "slop" in the joint.

1 jam nut "should" be enough to prevent the rod turning and un-knowingly adjusting your rudder angles.

You may just need to reset the tie-bar engagement in the clevis ends, or you might need a longer rod... (it is too easy to suggested a title for that post)

Measure the distance from pin to pin on the rudder arms,
remove the entire tie-rod,
on the bench adjust the engagement so that it is equal in each clevis
reset the clevis end dimension to the measurement you took
verify that you have equal thread engagement in each clevis,
if this still does not give you enough engagement you might need a longer tie rod

Capt.Bill11 said:

Your boat was built in Asia, are you sure it's not metric?

Click to expand...

I've been wondering that too, but much of the other hardware isn't. The 14 thread gauge seemed to fit very well, but I'll see if the yard has a metric set. Thanks!

Looking at the picture I'm not sure why you'd need a jam nut. The Clevis is pinned to the rod with a cotter pin. So there is no way it or the rod can rotate.

Capt.Bill11 said:

Looking at the picture I'm not sure why you'd need a jam nut. The Clevis is pinned to the rod with a cotter pin. So there is no way it or the rod can rotate.

Click to expand...

There is slop between the clevis and rod, whether from age/wear or original misfit. It translates to a very small wobble in the rudder if you twist it. Everything else is new, fixed or cleaned up so I'd like this to be.

angus99 said:

There is slop between the clevis and rod, whether from age/wear or original misfit. It translates to a very small wobble in the rudder if you twist it. Everything else is new, fixed or cleaned up so I'd like this to be.

Click to expand...

Just use a good quality solid SS hose clamp. I really doubt that small amount of slop I'd hurting anything.

Capt.Bill11 said:

Just use a good quality solid SS hose clamp. I really doubt that small amount of slop I'd hurting anything.

Click to expand...

I may do that if having one fabricated ends up costing a lot.