Need help finding 1/2"-18 nuts for tie-rods of old hydraulic cylinder.

[Grateful Farmer]

Hey All,
Does anyone know where I can locate 1/2"-18 nuts for tie-rods for an old hydraulic cylinder. I can find taps and dies for this old size, but no nuts. Otherwise, I will have to buy 4 new rods and nuts. Any ideas?
Thanks!

 

[pomester]

Is this what you are seeking?

Edit: NVM - I see the '18-8' is the grade, not the thread. A cursory search does't pop up anything - how much tension is associated with the assembly? could you tap out a 1/2-20 nut and make that work? Maybe double nut it?

 

[Ray,IN]

Got a full-service Hyd. shop in your area? If anyone can get them, they can. BTW, could they actually be metric size?

 

[Jim.ME]

Are you measuring and counting threads or using a pitch gauge? I ask as it is easy to miscount threads (BTDT). I guess you tried 1/2-20 nuts and they won't go. What is this cylinder from?

 

[Phill Tibbetts]

A machine shop could make them pretty easily.

 

[Tramway Guy]

3/8” NPSM pipe thread is 18 threads per inch. But the OD is too large. Just realized that. Never mind.

 

[Grateful Farmer]

Thanks All! They are for the tie rods that hold to 2 caps on the hydraulic cylinder. They are under great tension. They are from a 1964 Wagner front end loader on a Ford 4000. I used a thread gauge to definitely determine the size. I find it crazy that the taps and dies are readily available, BUT NO NUTS!

 

[Jim.ME]

Thanks All! They are for the tie rods that hold to 2 caps on the hydraulic cylinder. They are under great tension. They are from a 1964 Wagner front end loader on a Ford 4000. I used a thread gauge to definitely determine the size. I find it crazy that the taps and dies are readily available, BUT NO NUTS!

Dies and taps are available for many specialty thread pitches, that are used in limited amounts in specialized applications. It sounds like the manufacturer of those cylinders, at the time, thought theirs should be special. There are newer higher pressure tie rod cylinders that use the standard commonly available thread pitches.

You don't say how long these tie rods are, but I would look at changing them to grade 8 or B7 rods with common thread pitches either fine or coarse. Grade 5 would likely be as good as the ones you have.

 

[Grateful Farmer]

The rods are 21.5" long. I believe I will have to replace the rods because I am having no luck locating 4 nuts. Nothing is simple... thanks for the input all.

 

[Farmalldude45]

The rods are 21.5" long. I believe I will have to replace the rods because I am having no luck locating 4 nuts. Nothing is simple... thanks for the input all.

If you can find the tap, why not buy some hex bar and a tap drill and make your own? Might not need to buy the drill if it is a standard size or close to one.

 

[Stan Coryell]

Are you sure they aren't 9/16- 18?

McMaster- Carr has them.

95462A530

 

[Grateful Farmer]

Yes, they are definitely 1/2" - 18 threads/inch. I considered making them, and it may come to that. I think I need a time machine.

 

[Ray,IN]

This is the only ½-18 nut I've been able to find. I suspect you can use a ½-20 nut and re-tap it to ½-18 and make it work. However these nut will work under the entire load of the cylinder and might strip out.
If you decide to make these ½-18 threaded nuts use a 29/64 drill, which should leave approx. 75% threads. Higher percentages of threads do not significantly add to thread strength, but are much more difficult to cut clean threads.
If by chance it does turn out to be 9/16-18, which is a standard thread, use a 33/64 drill.

 

[Grateful Farmer]

Thanks Ray, I saw those "nuts" as well, I don't think that they will work. I am really shocked that none of us can find normal 1/2"-18 nuts . I will break down and spend nearly $100 for 4 new 1/2" x 24" long connecting rods and 8 new 1/2"-20 nuts from McMaster-Carr.

 

[Timmycornpicker]

Thanks Ray, I saw those "nuts" as well, I don't think that they will work. I am really shocked that none of us can find normal 1/2"-18 nuts . I will break down and spend nearly $100 for 4 new 1/2" x 24" long connecting rods and 8 new 1/2"-20 nuts from McMaster-Carr.

Take it for what it's worth, but the machining doctor website says that M12-1.5 metric nuts will work on 1/2"-18 threads.

 

[Farmalldude45]

Thanks Ray, I saw those "nuts" as well, I don't think that they will work. I am really shocked that none of us can find normal 1/2"-18 nuts . I will break down and spend nearly $100 for 4 new 1/2" x 24" long connecting rods and 8 new 1/2"-20 nuts from McMaster-Carr.

6" of 3/4" hex bar is less than $5 + shipping. Tap and tap drill kit for about $25 + shipping. You need to put a value on your labor, but I might think the $100 could be money well spent. Of course, you will have a tap and drill bit at the end of the day. But, if your luck is like mine, you can invest in raw material and tools and have one of the old tie rods break just as you get it tight.

 

[DanielW]

Are you 100% sure it's 0.5" and not 0.54"? 1/4 NPT is 0.54" O.D. and 18 TPI. 1/4 straight thread NPT nuts should be fairly readily available.

If not, I'd either buy hex bar and make as suggested, or (more likely what I'd do) make your own tie rods. I've used grade 8 threaded rod to make my own tie rods several times.

Or better yet, for an old Wagner loader cylinder that's probably a little worn on the barrel and rod and likely uses old V-pack seals, I'd just size the equivalent new cylinder and buy a new aftermarket cylinder that fits for a few hundred $$. I find it seldom worth the effort to re-seal or work on any old hydraulic cylinders anymore. Most of them use lousy old v-packs, have worn/scored/sprung rods or barrels, are possibly only single acting, don't have chromed rods so the surface rust they develop tears apart seals, etc. For a couple hundred dollars at somewhere like Princess Auto I can usually get a new aftermarket cylinder that's far better than the original. I did this for the Wagner loader we have on an old Cockshutt.

 

[Grateful Farmer]

The M12's are too small. The 1/4 NPT idea is interesting, but I don't see any structural nuts this size during a quick search.

Daniel, you are probably right that I'm throwing good money after bad, but it going to try. I will replace the cylinders complete if needed.
Thanks all for the ideas. I bit the bullet and spent $113 with shipping to replace the 4 rods and 8 nuts.

 

[Phill Tibbetts]

If you plan to thread your own rods you better make sure you have a way of holding the die square to the rod or you will end up with a messed up thread. Maybe you have a die handle with an aligning plate? I've seen a lot of messed up threads because someone tried to thread without the proper die holder.

 

[Grateful Farmer]

OK, will do Phill ! Thanks.