Thread: Which bolts to use with heim joints

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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

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

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

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

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.

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

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?

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?

...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.

Originally Posted by IC2

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

....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