Which bolts to use with heim joints

I'm using heim joints at the ends of my tie rod, and just found (after 15,000 miles) that the bolt on one end (passenger side) has loosened in the bores of the heim joint ball and steering arm. Because of their short length, the bolts I had used (stainless 1/2-20 x 2 1/2) were fully threaded, and I believe that the loose fit is because the threads run through those bores and have now "squashed down" a little.

What does everyone else use for this? Are there special bolts I should use, or should I use longer bolts with a solid shank and thread them myself so that no threads enter the bores?

Were those grade 8 stainless? I've never had a problem with running a regular grade 8 bolt in these. Some shoulder would help as it swells up a little in that area and would act as a shoulder. I would ask someone like Garner-Wescott or Stainless Specialities for a catalog or go on line and look for ones that have as much shoulder as possible. And, I would use Nylock nuts with them for sure.

Don

I'm surprised 1/2-20x2.5 is fully threaded, but since you ask, McMaster-Carr have almost anything you need: http://www.mcmaster.com/#cap-screws/=3m4kqf

When you replace them, I suggest you get the standard version here - and if you scroll down, there is a drawing: http://www.mcmaster.com/#92198a439/=3m4l9d

Me, I would use 180,000psi ARP bolts there:LOL:

I encounter this often on drag race chassis inspections. "Grip length" is the term used for the smooth, unthreaded portion of a bolt. The bolt chosen should have a grip length just slightly longer than the length of the bore in the Heim and steering arm, so that the threads don't start until you have cleared both.

Also, proper installation of a Heim dictates the use of safety washers such as the part number MCW8 shown here for 1/2" fasteners.....
http://www.midwestcontrol.com/catdis...ort.php?pg=552
Use a washer on each side of the Heim, with the small diameter of the cone resting on the ball of the Heim. This will give the Heim room to move without binding up and further, will catch the linkage in the event the Heim ball separates from the housing. That's why they're called safety washers. Use this arrangement regardless of whether the installation is in single shear or double shear and you'll have a bulletproof install. This became such a problem on Junior Dragster steering linkage that I purchased a bag of safety washers to give to the teams to fix their binding problems. Even professional chassis builders don't get it.

Tech - thanks for posting the supplier!!!! I had looked far and wide for a supplier for those washers (as well as rod ends). I ended up making some haffarsed versions, but now will get some 'real' parts

aircraft parts need aircraft hardware---use the proper grip length AN bolt--they have a HIGH TOLERANCE diameter to fit the holes of the size bolt---you can get them already drilled for safty wire or cotter keys and castle nuts----don't ever drill thru a bolt/nut as you will kill the integerty of the bolt and nut , almost surely causing a failure

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Originally Posted by jerry clayton

aircraft parts need aircraft hardware---use the proper grip length AN bolt--they have a HIGH TOLERANCE diameter to fit the holes of the size bolt---you can get them already drilled for safty wire or cotter keys and castle nuts----don't ever drill thru a bolt/nut as you will kill the integerty of the bolt and nut , almost surely causing a failure

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Thanks for the additional heads-up Jerry, GOOD STUFF!!!!:3dSMILE:

Great information everyone. Thanks very much, especially for the sources that I hadn't located. Nothing like being able to get answers on a Sunday afternoon and browse online stores that are open when their brick and mortar counterparts aren't.

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Originally Posted by jerry clayton

aircraft parts need aircraft hardware---use the proper grip length AN bolt--they have a HIGH TOLERANCE diameter to fit the holes of the size bolt---you can get them already drilled for safty wire or cotter keys and castle nuts----don't ever drill thru a bolt/nut as you will kill the integerty of the bolt and nut , almost surely causing a failure

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My apologies: I was pretty off on the bolt size - it should have been 5/8-18, not 1/2-20. Gone are the days when I could judge sizes from a distance. In any case, I measured the inside of the heim and it's as close to .625 as my micrometer can measure. Hardware store bolts are a thousandth or two undersize and if I'm going to replace what I have, I might as well get the right bolts. McMaster-Carr has grade 18-8 stainless in my size, but those aren't necessarily the "aircraft quality" I'm looking for. Does anyone know of a source that will sell me just two bolts, and that they've had good service from?

If I can't get the bolts I want with a tighter fit, how does everyone feel about light knurling to tighten them up?

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Originally Posted by Dorsey

My apologies: I was pretty off on the bolt size - it should have been 5/8-18, not 1/2-20. Gone are the days when I could judge sizes from a distance. In any case, I measured the inside of the heim and it's as close to .625 as my micrometer can measure. Hardware store bolts are a thousandth or two undersize and if I'm going to replace what I have, I might as well get the right bolts. McMaster-Carr has grade 18-8 stainless in my size, but those aren't necessarily the "aircraft quality" I'm looking for. Does anyone know of a source that will sell me just two bolts, and that they've had good service from?

If I can't get the bolts I want with a tighter fit, how does everyone feel about light knurling to tighten them up?

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...a couple thou is a nice fit, but probably not .015.

Scroll down here and choose a supplier.
http://www.magicyellow.com/category/...Newark_NJ.html

Personally, I wouldn't choose stainless for a suspension or steering fastener, but hey, you do as you please. If I wanted a shiny fastener, I'd go Grade 8 steel and have it plated with ELECTROLESS nickel.

DO NOT USE ANY ELECTOLYSIS PROCESS ON ANY SUSPENSION OR STEERING COMPONENTS OR FASTENERS DUE TO HYDROGEN EMBRITTLEMENT.

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Originally Posted by IC2

...a couple thou is a nice fit, but probably not .015.

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....an update.

The McM C 18-8 are probably not good enough(at least not for me) as they are not rated for grade, and are but 70,000psi. Their black Gr8, they are 180,000psi

ARP makes some HS SS fasteners. You want 17-4 PH stainless which is 170 ksi material.

I like these or G8 as well, although if you look at suspension stress analyses you will generally find even G5 fasteners have substantial safety factors in a good design. I have seen some designs that ain't that good though. ;)

Kitz

try Aircraftspruce co---they have a web site

I don't suppose those Seals-it heim joint washers, with the rubber edge seal would count as a safety washer? I have seen them recommended for use on the panhard bar, and other suspension components using heim joints to help protect them from dirt, etc.

Would you recommend them?
http://www.sealsit.com/rodend.asp

The rubber seals have zero strength so they are not a safety washer. The safety washer (as explained by others earlier) must be larger than the inner race of the rod end so that the bolt head cannot pull thru in case of failure. Of course, if you put a big washer on each side of the race, the angle of compliance is reduced....that is why they sell rod ends with extended races....to get the bolt and washer out further to allow more angle. The rubber seals have a metal ring on the inside and go over the bolt; one seal on each side. They also do a nice job of trapping dirt next to the race.

By the way, for those who are not aware, rod ends come in several "grades" like bolts do. If you are using 5/8" or 3/4" rod ends, for suspension applications, make sure the MINIMUM load rating is about 30,000 pounds (higher is better). If you are buying the commercial rod ends ($10 to $15), they are rated at perhaps 10,000 pounds and you are asking for trouble. Good rod ends are not cheap, there is no "bargain" on the quality aisle. Baker Precision is a good source for rod ends; their web pages have technical specs plus good practical info regarding rod ends. Just like bolts, you do not want to bet your life on a cheap part.

mike in tucson

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Originally Posted by robot

They also do a nice job of trapping dirt next to the race.

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Good point! :eek: Thanks Mike.

I bought chrome-moly rod ends from Speedway at about $30 each a few years ago (http://www.speedwaymotors.com/Chrome...s-LH,7063.html). If they're not high quality, they certainly feel like it because they're both beefy and heavy. I also found a pair of new AN10-21A bolts at a good price. Now, because they're not drilled (A suffix), is it generally acceptable to use lock nuts rather than the cotter pins that I'd prefer? On some of the aircraft sites I visited during this research, that seemed like one of the acceptable solutions to combat bolts loosening due to vibration.

Just when you feel comfortable that you know pretty much what you need to know about a topic, this whole AN bolt thing came up, and it was interesting to learn all about them, especially their wide variety and how to decode the designation.

Dorsey, the main concern about the rod ends that you bought is that they have no information regarding what they are.....just like bolts, the seller should publish the specs...for bolts the spec is defined by the Grade. You might have really good rod ends or you might have something less.

Also, using a lock nut is acceptable for street but you should check with your race sanctioning body. NEVER use a nut with the Nylon (called Nylok), instead, use a nut with the deformed threads....when we remove a bolt and nut on our rock crawler, we throw it away...we never reuse a bolt or nut. The deformed thread nuts are a bear to put on by hand but they do not loosen or come off.

mike in tucson

I suspect Mike is talking about "Stover" nuts? (They can be re-used)
Quote from Fastenright Ltd.

Stover Nuts are vibration resistant self locking nuts. Advantages of using the Stover Nut Include:

The self locking function of the Stover Nut is still effective after a number of applications, hence it can be used many times.

The Stover Nut is an all metal Stiff Nut and is resistant to shocks, vibration and dynamic loads.

Stover Nuts is a 1 piece all metal (class 8) nut. The locking function of the Stover nut us achieved by the deformation of part of the nut.

The nut will run smoothly until it reaches the deformed part after which the clamping force will subsequently increase.

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Originally Posted by robot

Dorsey, the main concern about the rod ends that you bought is that they have no information regarding what they are.....just like bolts, the seller should publish the specs...for bolts the spec is defined by the Grade. You might have really good rod ends or you might have something less.

Also, using a lock nut is acceptable for street but you should check with your race sanctioning body. NEVER use a nut with the Nylon (called Nylok), instead, use a nut with the deformed threads....when we remove a bolt and nut on our rock crawler, we throw it away...we never reuse a bolt or nut. The deformed thread nuts are a bear to put on by hand but they do not loosen or come off.

mike in tucson

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Years ago, weren't these called Elastic Stop Nuts? Or, is that something entirely different? The place that made those is now called ESNA (Elastic Stop Nuts of America) and is about ten miles from where I live, or was a few years ago.

Something else new - "Stover" nuts. Never heard of them, but I'll soon become an expert. Maybe all of this is new because I have no interest in racing or aircraft, and hence haven't kept up with it. I want my car to look pretty, so I'm still agonizing over how to hide raw bolts in my exposed front suspension while ensuring that it's still safe construction.