MikeR
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| posted on 19/4/04 at 08:03 PM |
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Rod Ends / Spherical Bearings
Ok guys, I'm going to fit a rod end to my panhard rod. Any suggestions of size / quality / strength / Company to buy from???
Cheers,
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NS Dev
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| posted on 19/4/04 at 08:38 PM |
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For rod ends you will struggle to beat www.trackstore.co.uk (ring them they are very very helpful!!) for quality vs cost! You want the CMXR8 rod ends,
1/2" x 1/2". (£11 each)
Rally design do the cheap "Carborace" ends which are basically mild steel and are okish but for an extra couple of quid I'd go for
the CMXR8's which are top quality PTFE lined chrome-moly items.
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TPG
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 posted on 19/4/04 at 08:41 PM |
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Rod end
Me,I'd use an M12 Thread(Easy to weld a M12 nut into the rod and retap,Dead standard).A 12mm hole thru the end for use with a 12mm bolt(not set
screw)for firm location.These are standard items from the likes of B.S.L. or Wyco.I'd look local to you,Or on the web for bearing suppliers.Rs
have them for £11 +vat +p+p and they are high priced.Shop around.The Rs stock is 198 9106 @ rswww.com.I'll try to attach a
link.www.rswww.com
..Which was nice..
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craig1410
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| posted on 19/4/04 at 10:43 PM |
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I got mine from Rally Design www.raldes.co.uk. They also do threaded inserts to match the rod-end and can supply suitable tubing, into which the
inserts fit, in meter lengths. I'd advise you to get one right hand threaded rod-end and a left hand threaded rod-end to match. That way you can
slacken the locknuts and just twiddle the rod (ooer!) until you get the desired position. Makes adjustment sooo much easier. RalDes do both LH and RH
inserts and rod-ends.
As for size, don't be fooled by cheap immitations as there are rod-ends and ROD-ENDS! You can get a good quality 1/2" rodend which has
twice or more times the strength of a poor quality one of the same size. Here are some examples from RalDes's catalogue (I agree that 1/2"
teflon coated is ideal btw):
Carborace - 5800lbs - £8.25
Nat'l MSM8T - 7106lbs - £7.20
Nat'l MAX8T - 16646lbs - £13.32
Nat'l MTSM8T - 6660lbs - £10.96
Nat'l TSMX8T - 16238lbs - £18.28
Nat'l UMAX8T - 23632lbs - £29.75
All part numbers are for RH thread parts. Left hand threaded parts usually have same load rating but cost only a few pence more. Load rating is USRL
(Ultimate Static Radial Load) and is in pounds force.
They all have different characteristics which are described in the raldes catalogue but I concluded that the MAX8T was the best for my panhard
application. Unfortunately raldes didn't have any in stock and substituted the carborace ones instead... I accepted them purely to get the car
on the road but I'll be replacing them straight after SVA is complete with something a bit meatier like the MAX8T. Trailing arms are not so
critical because there are 4 of them to share the burden but if the panhard rod breaks then you will have problems... I am using MSM8T's on my
trailing arms.
Get PTFE lined ends to avoid maintenance (just keep them clean) and I was advised not to fit rubber boots because they just trap dirt. The PTFE ends
are self cleaning.
Other things you will need are two 1/2" inserts (£2.32 RH, £2.46 LH) and one meter of tubing (£5.02). The inserts slide inside the tube and weld
around the edge. They are a "top hat" design and so are easy to weld as they don't slip too far in. You also need locknuts (£0.21 RH
and £0.30 LH)
I hope this helps,
Craig.
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Peteff
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| posted on 19/4/04 at 11:02 PM |
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I used M12 from a local bearing supplier and a friend made me some knock in threaded inserts to put in the end of my trailing arms and weld in place.
I used one in the axle end of the panhard rod as well. They advised against the lined ones for the sideways force of the panhard rod, o.k. for the up,
down and sideways of the trailing arms.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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NS Dev
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| posted on 19/4/04 at 11:08 PM |
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If you have a look at my photo archive, the grasser photos will show a nice range of sizes/qualities of rod-ends, from carborace 5/8x5/8 (front
wishbones) to full chrome-moly 3/4x3/4 ones on the rather nastily loaded rear trailing arms!!
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craig1410
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| posted on 19/4/04 at 11:14 PM |
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Pete,
I'm not sure what "sideways" force you are meaning. Can you explain please?
If there is any axial (sideways) force present trying to dislocate the rod-end then IIRC it is usually rated to about 10-15% of USRL. Therefore it
would take around 1 ton of force to dislocate the MAX8T! That would have to be a seriously badly designed 5 link suspension design surely?
Interestingly the PTFE lined MAX8T has exactly the same USRL as the non PTFE lined MAX8 of the same size.
I'd still recommend PTFE lined rod-ends otherwise you will have to lubricate them and the grease/oil will attract dirt and very quickly wear the
rod-end. This is the advice I was given on this forum by those more experienced in this area than me.
Cheers,
Craig.
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NS Dev
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| posted on 19/4/04 at 11:29 PM |
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You are quite right Craig, I have had quite extensive experience of this sort of thing!! The only time I have had a problem with PTFE lined joints is
on the spherical top mounts on a car with McPherson struts (nova rally car with homemade eccentric top mounts). here the full weight of the front of
the car is trying to dislocate the bearing, and when landing repeatedly from a few feet up in a 1 tonne nova car in grizedale forest it pushed the
teflon liners out (we went to steel on steel bearings after that). However for anything at all on a locost, the loading is so light that PTFE is
definitely a benefit as is is smooth running and has no play like a steel-steel one.
The rear arm joints on my grasser are PTFE lined and they take a real hammering, they are still perfect after a years racing (and getting full of
soil!!)
incidentally, the advice to skip the rubber boots is no bad thing, as long as you wash any road salt off regularly.
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MikeR
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| posted on 22/4/04 at 12:03 PM |
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ordered from trackstore - seemed a really nice bloke and if he's got them in stock I'll have them tomorrow (he's not 100% sure about
1 part, but if its not in stock i'll have them early next week).
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craig1410
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| posted on 22/4/04 at 12:11 PM |
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Mike,
What size did you go for in the end? Do Trackstore supply threaded inserts or are you just going to weld nuts inside the tube?
Cheers,
Craig.
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MikeR
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| posted on 22/4/04 at 04:29 PM |
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I went for the ones suggested by NS Dev (1/2 inch) for two reasons ....
1) all my suspension bolts are 1/2inch
2) NS Dev reconmended them - I've met him in real life and recon he might have an idea what he's talking about!
I ordered 1 left and 1 right rod end - CMXR8, two inserts & two nuts.
I'll let you know how I get on.
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NS Dev
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| posted on 22/4/04 at 04:52 PM |
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Hi Mike!!
Cheers for that! It is a bit strange to us metric brits to see UNF rod ends but nearly all of the rod ends in the UK are made in the USA, hence the
imperial measurements. The rod-ends fitted to 99% of competition cars are imperial, strange but true!
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Peteff
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| posted on 22/4/04 at 06:02 PM |
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The horizontal forces along the panhard rod in cornering when it is being pushed or pushing into the axle as opposed to the up and down which is its
natural range. This was the advice from the man who sells the bearings and doesn't want someone coming back to tell him he sold them the wrong
thing for the job.
 
Rescued attachment rosejoint.JPG
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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MikeR
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| posted on 22/4/04 at 06:06 PM |
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Pete, I'm confused.....
are you saying that the rod ends i've bought aren't up to the job?
I thought the panhard rod was mostly a push / pull force compared to up / down.
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craig1410
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| posted on 22/4/04 at 06:15 PM |
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Pete,
I think I just about understand what you are meaning but I don't think it applies to my own setup as my axle mounted rod end is not mounted in
the same orientation as yours. I've never actually seen a panhard rod mounted in the way you have mounted yours, most (in my albeit limited
experience) are mounted so that spherical bearing is being "rotated" by up and down suspension movement rather than
"articulated" if that makes sense. Therefore my "angle of misalignment" stays virtually constant during suspension
movement.
Here's a pic to hopefully clarify:
and another close up:
Cheers,
Craig.
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JoelP
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| posted on 22/4/04 at 06:24 PM |
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gotta say, thats a bloody nice back end craig. home made or part purchased?!
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britishtrident
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| posted on 22/4/04 at 06:27 PM |
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Aerospace and single seater teams still tend to standardise on UNF threads --- UNF bolts have advantages in that the core diameter is bigger than the
standard ISO metric coarse thread in widespread use and ISO metric fine series threads tend to be too fine and tend to jam and seize in automotive
suspension allpications..
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craig1410
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| posted on 22/4/04 at 06:44 PM |
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Thanks Joelp, I'm sure your back end is equally nice...
It is a bit of both to be honest. I bought it from "ChazPowerSlide" from the LB forum who had I think bought it from someone who had
bought it from MK Engineering (can't remember the whole story now).
Anyway, When I got it, it came in 7 parts: The pre-bent de-dion tube, the pre-drilled and tapped sierra hub carrier plates, the pre-assembled de-dion
"Ears" and the big bit of black pipe through which the driveshafts run. Arguably the easy bit had been done leaving me with the tricky job
of aligning and welding it all together...
My website give all the gory detail of how I did it and I got someone with a nice big Mig welder to seam weld it once I had it tacked into position.
My 120Amp welder wasn't up to the job and neither (arguably) were my welding skills...
There are drawings and plans on my website detailing how to build your own de-dion axle just like this one if you like it so much. I should also point
out that this picture is from nearly a year ago so it has moved forwards a bit since then. I'm busy painting my chassis and suspension and will
post a more recent picture soon.
BritishTrident, I agree that 1/2" UNF is ideal for suspension as it is a nice half way house between metric and metric fine in terms of
threading. Somehow it just feels "right" and gives you confidence that the bolts aren't going to break or fall out anytime
soon....which is good!
Cheers,
Craig.
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craig1410
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| posted on 22/4/04 at 06:45 PM |
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Here's a more recent pic before I stripped the chassis for painting:
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britishtrident
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| posted on 22/4/04 at 06:50 PM |
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quote:
Originally posted by craig1410
Here's a more recent pic before I stripped the chassis for painting:
Nice work on the de dion
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craig1410
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| posted on 22/4/04 at 07:06 PM |
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Thank you kind Sir!
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Mark Allanson
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| posted on 22/4/04 at 07:30 PM |
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You could always use a Nissan bluebird raduis arm extended with 19mm seamless tube. Cost me about £3 for the whole rod, and fully adjustable.
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
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Peteff
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| posted on 22/4/04 at 08:32 PM |
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I thought the panhard rod was mostly a push / pull force compared to up / down.
The rod end is taking the weight of the car on its contact point with the bolt whichever way up you mount it. It takes a battering I mounted mine so
it would be in true double shear. I saw one panhard rod bent by enthusiastic driving and would move the joint to the axle end of your bracket by
moving the other end out a bit if it was mine. The bearing may be up to the job but the dealer I bought mine from thought the battering (push/pull as
you call it) would eventually compress the teflon and allow the inner to come out as on the Nova of NS Dev.
I'm not sure what "sideways" force you are meaning. If you aren't going to get sideways you should be alright.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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craig1410
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| posted on 22/4/04 at 09:48 PM |
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Peteff,
Sorry mate but I'd have to disagree with you there. Whilst I agree that the bend in my de-dion axle doesn't permit a perfect alignment of
my panhard rod, I would rather have the axle end mounted a couple of inches away from the axle on a double shear bracket than end up with my PH even
farther away from being parallel to the lateral axis of the car.
Ideally the PH should be level with the ground at ride height and parallel to the lateral axis. This is surely the best way of avoiding any bending or
sideways forces.
Rod-ends are designed to cope well with radial loads (ie. loads in the same plane as the long axis of the PH). It is axial loads which you
should try to avoid as I mentioned earlier because the rod-ends are only rated at about 10-15% in the axial direction compared to the radial
direction.
The other thing to bear in mind is that by mounting the rod-ends in the orientation which you have you may run out of "misalign angle" on
full bump or full droop. Rod end max misalign angle is usually specified between 10 degrees and 20 degrees and the more angle you have, the less load
the bearing can sustain. Eventually the through bolt will foul on the rod end outer casing which will place very high bending loads on the rod end,
brackets and panhard rod. IMHO it is better to mount both ends of the panhard rod in the same orientation with each mounting bolt passing through the
rod end in the longitudinal axis of the car. That way the rod end is simply rotating during suspension travel instead of articulating.
That said, if it works and passes SVA then who am I to argue...
Cheers,
Craig.
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Peteff
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| posted on 23/4/04 at 09:03 AM |
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That's alright.
I don't think the little fillets on the back of the bracket are doing much towards making it stronger but the bolt thickness should hold it on
its own. With 3" of suspension travel the articulation on the rod end is less than 4 degrees. The other end of mine is a poly bush mounted
normally. I know in the ideal world we would mount the rod parallel and in line with the centre of the axle on its wheels and loaded but it's a
car built from bits of other cars out of what we can get so there are bound to be compromises. We all do things other people would do differently. I
would have welded a piece of 50mm RHS with the end plated with 3mm and a captive nut to the back of the carrier to space it out or with the bracket on
the front instead of 19 washers but that's me. It's a forum and if we all built a car between us it would probably be perfect in
somebodies eyes.
are you saying that the rod ends i've bought aren't up to the job? I didn't say anywhere that they aren't up to the job
but what did NS Dev swap his Nova ones to, the same as my supplier recommended for the panhard rod. He's probably a belt and braces guy but I
trust him, he wasn't trying to sell me the dearest but thought they were best suited to the job.
[Edited on 23/4/04 by Peteff]
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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