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Rod End Quality
RazMan - 7/7/07 at 10:20 PM

It seems that the 1/2" rod ends on my front suspension are totally knackered after 5K miles - really dissappointing.

What are the best type for a suspension application?


turbodisplay - 7/7/07 at 10:23 PM

Did you use a rubber cover? without a rubber cover dirt gets in and wears the ball joint.

Rally design do these covers.

Darren


Fatgadget - 7/7/07 at 11:21 PM

As far as I am aware,rose joints are not designed for day to day use. Even if you use boots for protection,the moisture trapped will cause them to corrode rather quickly.


nitram38 - 8/7/07 at 05:49 AM

Did you spray anything on them?
There is a special spray on ptfe product for rod ends that lubricates without attracting dirt. It might help a bit.


RazMan - 8/7/07 at 06:50 AM

I was completely unaware that there were any covers available for rose joints and the only thing I have sprayed them with is the Jet Washer

Obviously it is now too late for my existing rose joints, so what spec should I look for as replacements? So far I have found versions with plain bearings, teflon bearings, ball bearings and roller bearings. Lube nipples are available on some too, which would obviously solve the moisture / grit problem. and I've found some useful looking boots in Demon Tweeks which might be a worthwhile addition they should keep out the dirt if they are filled with grease during assembly.



and some different boots in Rally Design



Here's a pic to show my particular setup


[Edited on 8-7-07 by RazMan] Rescued attachment Front Wishbones.jpg
Rescued attachment Front Wishbones.jpg


turbodisplay - 8/7/07 at 09:55 AM

I`m using 3/4" rod end will the rally design boot.
Filled with grease, I cannot see much difference to a ball joint, except the slightly less contact area.

Darren


MikeRJ - 8/7/07 at 08:19 PM

quote:
Originally posted by turbodisplay
Filled with grease, I cannot see much difference to a ball joint, except the slightly less contact area.


The crucial difference is that a ball joint (e.g. track rod end) is preloaded with an internal spring, so remains tight as the bearing surfaces wear, up to a point. A rod end is not usualy preloaded at all, so as soon as it's worn it will introduce some free play.


Doug68 - 9/7/07 at 02:13 PM

To go off topic a little bit...

I'm just looking into buying rod ends for the top wishbones on a set up similar to RazMans.

The question is to go with PTFE lined items or not?


RazMan - 9/7/07 at 03:49 PM

Definitely PTFE but the good ones are not cheap.
I have just been speaking to Autosport Bearings and they recommend National Rod End TSMX8T (about £20 each) or if you can afford it, NMB ART8ECR at £50 each These are for 1/2"unf with 1/2" bore.

This is one of the few times I will happily ignore the ebay offers - £4.50 a pop will very quickly ..... go pop, and I want to keep my car as safe as possible for as long as possible.

Interestingly the rubber boots were not recommended and certainly not filled with grease - it rots the ptfe liners apparently.

[Edited on 9-7-07 by RazMan]


NS Dev - 9/7/07 at 04:27 PM

You want 2 or 3 piece, chrome moly (4130) bodied, 52100 (high carbon chrome bearing steel) balled rod ends with inserted ptfe liner.

The TSMX8T is that as far as I know, and you are certainly looking at £20 each for decent 1/2" x 1/2" bearings.

I use cheaper ones on my grasser but mileage is very low and I oversize them so they are well over spec (I use 5/8 x 5/8 ones on wishbones carrying a 125kg front end! )

In terms of "good" suppliers rather than cheap and nasty, you won't get much better than.............dammit, brain cell fade, chap from birmingham, uni lecturer I think, good single seater engineer......

Nick Skidmore, thats the man!


NS Dev - 9/7/07 at 04:28 PM

ps yep rubber boots are shite, they let water in at some point when they get hit by a stone then don't let it out and the rod end gets trashed.

never used them on the rally car and decent rod ends last ages.


Alan B - 9/7/07 at 04:41 PM

quote:
Originally posted by NS Dev
ps yep rubber boots are shite...........


And if I recall correctly.....extortionately expensive......


RazMan - 9/7/07 at 05:12 PM

quote:
Originally posted by Alan B
And if I recall correctly.....extortionately expensive......


Only a couple of quid but I won't be using them anyway.

Just placed an order for a similar spec that NS Dev stated - Autosport Bearings suggested an alternative priced in between the two quotes I mentioned. I will see how long they last.

Poly bushes on my next build methinks


Alan B - 9/7/07 at 05:35 PM

quote:
Originally posted by RazMan
quote:
Originally posted by Alan B
And if I recall correctly.....extortionately expensive......


Only a couple of quid but I won't be using them anyway...................


I agree that in the grand scheme of things a couple of quid here and there won't break the bank...and they know that...but I just begrudge paying 100 times (or thereabouts) the manufacturing cost for any item.....

Would I charge the same if I made them?...yeah probably if I could get away with it....

And, yes I understand they have tooling costs to amortise over possibly lowish volume...but still......

Anyhoo...rant over....


Doug68 - 10/7/07 at 04:29 AM

These have come out top of my list at the moment.
Buying them from here they seem to be good value for money.
Obviously the NMB / NHBB brand appears to be the best, holy cow they're flipping expensive!

Anyone got anything bad - good to say about the FK brand?

On another subject has anyone ever seen any sort of sensible fail safe device to 'catch' the 'A' arm if the rod end breaks?

Also 'Race' magazine here in Australia had a very good article about using rod ends in bending (which in case you don't know is a bad thing). I realized after reading this that the common setup (as per RazMans picture). Is using the rod ends in bending (just like I intend to do). Hence I intend to go silly over sized to make sure that breakage doesn't happen to me.


RazMan - 10/7/07 at 05:41 AM

They would seem to be a good alternative Doug, although from what I have been told (during my crash course on Rod Ends) it is probably best to stay away from the type with the lube nipple. To allow the lube (usually oil and not grease) to circulate, a larger clearance has to be engineered into the bearing so it will have more slack to start with.

In general though, rod ends are a compromise and in my case I havent got the space for poly bushes so I am resigned to the fact that I will be replacing them every few thousand miles.


RazMan - 10/7/07 at 05:44 AM

quote:
Originally posted by nitram38
There is a special spray on ptfe product for rod ends that lubricates without attracting dirt. It might help a bit.


Any links on this spray Nitram? Anything that helps make them last longer is a good thing

*edit* I just found something which looks worth a go - cheap too. I'll give the rod ends a squirt every week and see how it goes. Ebay Link

[Edited on 10-7-07 by RazMan]


Rob Lane - 10/7/07 at 07:47 AM

Hmmmm GT85, smells luverrrly


Fred W B - 10/7/07 at 08:25 AM

Rortys take on this

"Steer (pun intended) away from the "economy" rod ends unless you're prepared to do the sums on them.
Mild or CroMo steel bodies with PTFE liners offer good service and precision. The CroMo ones are usually two to three times more expensive than the mild steel ones and stainless are more expensive again.

If you stick with SKF locally, (very high quality metric rod ends BTW), their rod ends are metric and I'd recommend their glass lined SAKB 10F and SALKB 10F joints. They'll probably be more costly than other brands though. "

Cheers

Fred W B


Doug68 - 12/7/07 at 12:04 PM

RazMan,

This thing is called a "Boulder Bushing" and comes from here I assume these people don't actually make them themselves, but I've been unable to track down the manufacturer to date.

Does anyone know who it might be?

Other than the fact that they won't take up angular misalignment, which given your suspension picture doesn't look an issue, they look to overcome at lot of the rod end issues. If there were a slightly smaller size they'd be even better, as I expect this item to be a bit weighty. Also I don't know the hardness of the polyurethane used which hopefully wouldn't be too soft.

On the web I've also seen pictures of similar items welded together but they looked inferior to me. Rescued attachment bb_lg.jpg
Rescued attachment bb_lg.jpg


NS Dev - 12/7/07 at 12:39 PM

quote:
Originally posted by RazMan
quote:
Originally posted by nitram38
There is a special spray on ptfe product for rod ends that lubricates without attracting dirt. It might help a bit.


Any links on this spray Nitram? Anything that helps make them last longer is a good thing

*edit* I just found something which looks worth a go - cheap too. I'll give the rod ends a squirt every week and see how it goes. Ebay Link

[Edited on 10-7-07 by RazMan]



whooaaahhhh there!

GT85 is not dry film, its like wd40 with ptfe additive.

you want ptfe dry film lubricant, as used for injection moulding mould release spray.

like this stuff:

ptfe dry film spray


RazMan - 12/7/07 at 01:31 PM

quote:
Originally posted by Doug68
"Boulder Bushing"


Now those look like a superb alternative, although they are rather large at 3/4" thread and 5/8" bore. If they were designed into a new build they would certainly last a lot longer and road noise would be reduced as a bonus.

Thanks for the tip Doug

[Edited on 12-7-07 by RazMan]


Angel Acevedo - 12/7/07 at 05:41 PM

Eureka!!!
Gold mine to US builders, there should be something similar there at UK...

http://www.tellico4x4.com/index.php/cPath/0_2297_2744