phil m
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| posted on 24/11/02 at 03:57 PM |
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I've just bought some trailing arms off a Nissan Bluebird-£15- three of the four are adjustable.
Spooky at it is , the non-adjustable one is the same lenght as a book one. Therefore, if you really want adjusable arms this is a pretty good route to
go.
I need to replace the bushes and am not sure how much this will be yet , but it shouldn't be too costly
The only reason I went down this path was that my self made arms were a reallly tight fit into my brackets and I found that after trial fitting the
bushes got pretty mangled------A lesson here I think !!!!1
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johnston
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| posted on 24/11/02 at 07:41 PM |
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steve
the reason i suggested someone wit brains makes up a list is cos it would be to easy for someone who has no experiance of building or workin on cars
or any engineering background to look at a joint on someones car and go
"oh look he's only got 10mm joints on his cossie powered car they be more than adequate on mine"
only not to relise that there can be a load rating difference and those small joints could be very high quality F1 style joints
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stephen_gusterson
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| posted on 24/11/02 at 07:42 PM |
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Hi Alan
I am in agreement with you.
I dont have a clue on the following factors re the front suspension :
1. how much weight shifts forwards on an emergency stop.
2. how the effect of G's multiplies that weight shift, and from what to what!
3. The effect of hitting a pot hole at the same time.
4. how the static loadings of the joints actually translate, as a real life load factor, to the above scenarios.
I know the static ratings of my rod ends, but how they will cope on a car, bu%^er knows!
Thats why I went as big as I felt was sensible. However, if I use my bush based ajustable ends, I recon that falls into your 'see what works for
others' category - if they work on locost and spitfires, I should be taking a fairly safe low risk route rather than wondering if the next bump is
gonna make something break.
atb
steve
[Edited on 24/11/02 by stephen_gusterson]
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stephen_gusterson
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| posted on 24/11/02 at 07:45 PM |
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quote:
Originally posted by johnston
steve
the reason i suggested someone wit brains makes up a list is cos it would be to easy for someone who has no experiance of building or workin on cars
or any engineering background to look at a joint on someones car and go
"oh look he's only got 10mm joints on his cossie powered car they be more than adequate on mine"
only not to relise that there can be a load rating difference and those small joints could be very high quality F1 style joints
I agree with you Johnston - would be great to have real numbers, but I wouldnt hold my breath for enlightenment!
atb
Steve
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johnston
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| posted on 24/11/02 at 07:53 PM |
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i have seen it all to often in rallying circles when people say
" i get my rod ends from y cos x is too deer"
the trouble is y's own cars usully crash out more often cos of suspension failure
i know of 1 mk2 with coil overs leaf springs and located by trailing arms as well with one arm doing next too nothing cos theres that much slap in
cheap rose joint what fears me more is none of the so called expert drivers can feel it or hear it knocking
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johnston
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| posted on 25/11/02 at 10:37 AM |
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DUH!!!!
who spotted the delibrate mistake the carmentioned above doesnt have coilovers and leaf springs it has leaf springs and turreted for coil overs but is
just usin the upright dampers
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Spyderman
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 posted on 25/11/02 at 12:19 PM |
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Rod End joints
Steve,
I don't think you need to worry so much about rod end joint failure.
Surely the loading in the (chassis-side) joints is in compression and tension rather than shear as you are worried about? Especially with your
comparison with F1 cars.
As I understand it the loads from the wheel are transmitted inwards on rear A-arm and outward on forward A-arm. This is of course while vehicle is in
forward motion. Whilst stationary both forward and rear A-arm are in tension.
If the loads through the joints were in shear then there would be problems with binding and even possibly bending of brackets, as all the load would
go through rear half only of bracket.
Of course this cannot acount for shock loads, which is why you need joints with a reasonable side load rating.
Just my opinion!
Terry
Flameproof jacket at the ready!
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stephen_gusterson
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| posted on 25/11/02 at 04:45 PM |
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quote:
Originally posted by Bull
Steve,
I don't think you need to worry so much about rod end joint failure.:Just my opinion!
Terry
Flameproof jacket at the ready!
Hey Bull, Im a nice guy really!
Thanks for your words of encouragement, but I have a weird unconventional rear (ooh err).
Its a swing arm a bit like a metro or mini has. Before anyone tells me thats really crap on a rwd car i have heard that before! Im not gonna rally it
or nothing - as long at it goes around corners like a road car I will be happy, and the geomery was a lot easier to handle than a wishbone irs. The
problem with a swing arm is it does not allow for roll - but keeps really well alingned on bump.
Anyway, with the design I have , the outer joint I think is most heavily loaded.
I think I mentioned that IU built my suspension pretty tougth - this will give you an idea.
As the usual satement goes, its a morgan replica, not a locist, so if it weighs 750 kilo I dont care - If it falls apart and kills me I do. As I used
3mm wall 50mm box for this, re-enforced with 3mm plate, I guess the joints will go first..........
atb
steve
 
Rescued attachment swing.jpg
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Rorty
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 posted on 26/11/02 at 01:39 AM |
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Here here!
I think this is all getting a bit in-depth for the accumulated level of professional knowledge. No offence to anyone.
I'm no professional, I have vast experience though, gained through failures and successes.
Alan made a valid point: if you don't have the knowledge, or analysis capabilities, look to others who use similar materials, in similar
situations.
I've built race cars for both on and off road use, and over the years, have learned what works and what doesn't. Don't take my word for it though,
as I say, I'm not a professional anything.
Do look around at who else is using what, and see if it works for them, but don't get sucked into "well, he's using 10mm Rose joints in his 1200kg
car, so they'll be good enough for me" type scenarios.
As I pointed out in an earlier post, there are 10mm Rose joints, and then there are 10mm Rose joints. Ask the person with the 1200kg car exactly what
brand and quality of joint he's using.
I gained most of my knowledge racing off road, in cars with full roll cages. No one has ever been killed hitting a bush at 1200kmh in a full cage.
You lot don't have full cages, and will travell on public roads!
To be honest Steve, and no offence, but I think your suggested adjustable ends are overkill on several levels. They'll be unecessarilly heavy(I know
you'd sooner put safety before weight), but I really don't think they'd be any stronger than a well assembled bolt and tube, properly TIGged.
Have a look at those black coated, fabricated, adjusters I posted before. They're used in sub 2000kg drag cars, and they're just MIG welded
together!
I use TIG welded 1/2" UNF clevises on the inner ends of my tie rods. I've bent plenty of tie rods when either banging wheels with other racers, or
from hitting ruts, but I've never replaced or repaired a clevis.
Cheers, Rorty.
"Faster than a speeding Pullet".
PLEASE DON'T U2U ME IF YOU WANT A QUICK RESPONSE. TRY EMAILING ME INSTEAD!
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MustangSix
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| posted on 26/11/02 at 02:19 AM |
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Cast adjustble rod end source
Much earlier, Rorty posted a pic of a cast adjustable end that is typically used on American street rods. I just wanted to say that I've seen these
successfully used on a number of rods and those typically weigh in at over 2500lbs and most often with 250-350hp engines. They hold up just fine.
Can't say I've ever seen them in 1/2", but they're probably available.
They are not too expensive and can be had from Speedway Motors. Look in the street rod section under "rod
ends".
BTW, I've personaly ordered things from them and have been very happy with the service. Can't say what it would be like to buy from the UK, but
here in the States it's been a pleasure.
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stephen_gusterson
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| posted on 26/11/02 at 08:32 PM |
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quote:
Originally posted by Rorty
To be honest Steve, and no offence, but I think your suggested adjustable ends are overkill on several levels.
No offence taken, and if they are seen as overkill, thats great.
All my brackets are drilled for 16mm - it seems to me that most race type bushed joints - like the ones you show - are imperial. that would be a real
pain to change - I would have to make all my suspension parts again.
'Well TIGed' is a good point. You are talking to a man with a home hobby welder. As I cant buy imperial bushed fittings, the best way to make them
at home with what I have is to ensure as big a weld area as possible. Thats what my 'wrap over' saddle on the suggested joint gives.
Money no object, and 16mm joints being available, I would buy them.
They are not and money is an object!
No rush here - I have at least 6 months until the car will actually be driven anywhere.
atb
steve
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Mark Allanson
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| posted on 26/11/02 at 10:07 PM |
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Going back to the Bluebird trailing arms, are these the true trailing arms or the twin track control arms with run transversley? I had a look today
under a scrapper and the true trailing arms were not adjustable but the TCA's were.
They also looked like they were attached with M12's and not M10's - can anyone confirm?
Thanks
Mark
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