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Radius rod bolts

Let me pose a hypothetical question... If a rod end will never be exposed to more than 5000 #'s radial load , is one rated at 20K #'s going to last longer than one rated at 10K # ????? Or is using the heavier rated one simply overkill?? I'm betting there's some engineers on here..
dave
 
Hell, I'm have a Engineering degree and I'm learning all kinds of stuff....Hahaha....
 
Overkill is good in this situation. Better load rating is because mostly of materials, ie, Steels and plastics, clearences, etc. A quality Heim on a head-on load will last many, many years in a T, as its not ever stressed in the least. While the side load on the heim joint is probably less that 1.4 to 2 degrees at the front wishbone mount itself, theres not enough side load to dislodge a ball from its mount, unless a direct side impact from a wreck or rollover, which alot more stresses come into play, and a dislodged heim is the least of your worrys then.
I trust all the George says on Chassis stuff, he knows his schit, so to speak....He is a expert and knows Engineering, and I trust him 100%.

However, the old lady in her Escalade backing into the side of my T at the grocery store and putting her wheels up against my wishbone close to its adjustment point or on the heim makes my skin crawl....and the thought of her pushing my lakepipes into the side of my body....OUCH!
I just put the dust seal on each side of my heims and a SS washer as a backup incase of a catastrophic failure.

Afterall, I've seen motors explode thousands of times. Just a few have taken out the front tires, I've seen blower belts take out steering rods, I've seen people loose toes and/or parts of their feet to clutch explosions.
Seen 1 guy almost loose his privates to a rearend explosion in a old front motored digger....schit happens....and not all the time for the best.
 
I doubt that either one would ever wear out in our application. However there can be other considerations which is why I like to know the complete specs on bearings and other items. I wanted chrome plating for corrosion resistance. Just my preference. As for over kill, in our application it doesn't really matter if we add a few more ounces of weight. If we were building airplanes we would care about such things where every added ounce matters.

From the Midwest site:

MTM – Teflon

Ball: low carbon steel, surface hardened for wear resistance and plated for corrosion resistance.
Configuration: housing and stud dimensions are subject to change based on manufacturing considerations.
Housing: low carbon steel, plated and dichromate treated for corrosion resistance.

MXM – Nylon

Bearing Race: nylon
Ball: heat treated, hard chrome plated bearing steel
Finish: bright polished chrome
Housing: up to 1” sizes are 4130 chrome moly steel, 1.25" and larger sizes are an alloy steel.
 
I's Likes that T in the Pic Bill! Nice Pipes!
 
Laid my wrist on a pipe yesterday while it was running. One tube now has a black spot that used to be skin. Sandpaper and touchup paint coming soon.
 
How long (miles) have you been using the MXM rod ends? Have you gotten them wet (like driving in the rain), or are you also using seals?

Seriously, sorry to hear about your accident with the pipes. Hope you heal up OK.

Jack
 
Screaming Metal said:
Overkill is good in this situation. Better load rating is because mostly of materials, ie, Steels and plastics, clearences, etc. A quality Heim on a head-on load will last many, many years in a T, as its not ever stressed in the least. While the side load on the heim joint is probably less that 1.4 to 2 degrees at the front wishbone mount itself, theres not enough side load to dislodge a ball from its mount, unless a direct side impact from a wreck or rollover, which alot more stresses come into play, and a dislodged heim is the least of your worrys then.
I trust all the George says on Chassis stuff, he knows his schit, so to speak....He is a expert and knows Engineering, and I trust him 100%.

However, the old lady in her Escalade backing into the side of my T at the grocery store and putting her wheels up against my wishbone close to its adjustment point or on the heim makes my skin crawl....and the thought of her pushing my lakepipes into the side of my body....OUCH!
I just put the dust seal on each side of my heims and a SS washer as a backup incase of a catastrophic failure.

Afterall, I've seen motors explode thousands of times. Just a few have taken out the front tires, I've seen blower belts take out steering rods, I've seen people loose toes and/or parts of their feet to clutch explosions.
Seen 1 guy almost loose his privates to a rearend explosion in a old front motored digger....schit happens....and not all the time for the best.
Click to expand...
Amen on the old front engine diggers!!! I always say my prayers before I get in the seat, because I know time is short if rearend disassembly were to happen during the trip. I'm just saying.
 
Haven't driven in rain but did spin out on a wet street. Only have about 30 miles on it since I don't have it licensed yet. Do test drives and give rides in the subdivision. Both the nylon and teflon race joints are self lubricating [none needed] and self-sealing since the polymer race is perfectly tight on the ball. Also in our application the ball never really sees any side-to-side rotation of any amount so getting dirt into the joint should not be a concern with this application unless you're racing on a dirt track or going off-road on purpose.
 
The reason I posted the ? at the top of the page is this .... for those of us who count our nickles [cause we don't have $100 bills] buying what's usable is more important than buying "the best". It's like putting $$$ forged crank in a 2 bolt block that'll never see 5K RPM. Sure , it's a better crank , but it's certainly not needed. I want folks to know that buying the most expensive is not mandatory to building a safe car !!
dave
 
2old2fast said:
The reason I posted the ? at the top of the page is this .... for those of us who count our nickles [cause we don't have $100 bills] buying what's usable is more important than buying "the best".
Click to expand...

That's how I feel about it too. The only thing is, different applications make different demands on the ends. Our cars might not stress them much in terms of catastrophic failure, especially when the joint is rated at 16,000 lbs. However, that's not the same as tolerance change (play) that develops from wear. It's not clear to me that these two are necessarily related, except in a very exaggerated sense. For example, I would expect a 5,000 lb joint to show wear sooner than a 50,000 lb joint. Even that might not be a sure thing though unless one joint is simply a larger version of the other. If anything else is different - shape, heat treating, race material, lining etc., the picture changes. I think a more appropriate question might be which ends are specifically intended for automotive suspensions. I'll bet some of them with otherwise good specs don't hold up as well as others in this application. That's the type of information that would let us make an informed decision and optimize the value of the dollars we spend.
 
Last edited:
Another issue is dynamic load. The ratings are static, axial loads. Even under hard acceleration the joints are only experiencing a few hundred lbs of force. However, when you bump the front tire in a pot hole, on a curb, garage wall, anything that stops you suddenly, the joint might experience an impact load of thousands of pounds for a very short time. This is what damages bearings; dents in the race. I'll do a calculation and post it soon.
 
75 replies and what was the original question:thumbsdown: oh yeah, How tight should the bolts be ?:laugh: just saying.
 
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