How do you think this will affect the overall strength of the bracket and chassis?
Any help or ideas greatly appreciated as they all seem to be the same!!
When I have come to fit the wishbones into the chassis brackets they are about 5mm out which means that I will need to hammer the brackets into
place!!
How do you think this will affect the overall strength of the bracket and chassis?
Any help or ideas greatly appreciated as they all seem to be the same!!
Chassis and wishbones from the same manufacturer?
Often the brackets are slightly open IE more like _/ than |_| and when you tighten the bolt it squashes the arms parallel.
It's also not that unusual to need a packing washer (or two) on both sides of the wishbone to pack them out.
Certainly it's important that the arms don't go /_
Yes, they are both from the MK Kit
quote:
Originally posted by BenB
Often the brackets are slightly open IE more like _/ than |_| and when you tighten the bolt it squashes the arms parallel.
It's also not that unusual to need a packing washer (or two) on both sides of the wishbone to pack them out.
Certainly it's important that the arms don't go /_
That doesn’t look good 
id be having words with mk if I was you
If you bought the chassis and the wishbones from MK at the same time I'd be on the phone right about now kicking up a bit of a fuss!!
If you did (note the 'if' everyone 
) that's shocking, the first Stuart Taylor chassis I bought back in 2000 had similar issues but
not quite as bad as that! - you would of thought things had moved on in Locost building since then though
Unfortunately you need the brackets moving otherwise that's never going to work properly 
Powder coating doesn't look up to much either (I'm assuming it's powder coating?) it has to be said as well
[Edited on 26/9/07 by D Beddows]
Its quite usual to gently persuade them into position but if you need anything more than a firm push with your hands then it looks like
something's out of tolerance.
The shims/washers used to centralise everything should be the same id as the bolt
hth
quote:
Originally posted by SyKaTurbo
quote:
Originally posted by BenB
Often the brackets are slightly open IE more like _/ than |_| and when you tighten the bolt it squashes the arms parallel.
It's also not that unusual to need a packing washer (or two) on both sides of the wishbone to pack them out.
Certainly it's important that the arms don't go /_
so when i pack it out do the washers need to be the same overall diameter as the sleeve so i am not gripping the polybush?
quote:
Originally posted by BenB
You want to be gripping the polybush.
It's a common misconception that the polybush rotates around the central tube. They don't. Or rather, they can do, but they'll wear out in no-time. The bracket is supposed to grip the polybush which flexes to give the required movement.
He he I knew this was coming! Just to add then, my crush tubes ain't longer than the bushes.
Here we go again! Now, where did I put that popcorn smiley? 
I have just spoken to MK and they have insisted that pushing them into place and letting the tightening process pull them in will be ok so we will
wait and see!!
quote:
Originally posted by D Beddows
Powder coating doesn't look up to much either (I'm assuming it's powder coating?) it has to be said as well
It's complicated re the crush tubes eh?
I know the logic is that hard plastics will be able to rotate around a crush tube (therefore you want a crush tube slightly longer than the bush) but
if the rotation is free and without restriction why are you advised to not tighten the bolts up until the car is on the ground and weight-bearing?
That would suggest the bush is also clamped at a neutral setting and the resiliance of the bush to twisting is used....
just give them a whack with the hammer, will be ok
I've e-mailed Polybush. Hopefully they'll be able to put this question to bed once and for all....
Now, which are better, BECs or CECs?
The tight fit in the brackets looks like a bad design to me when they could be made to fit comfotably in the brackets which would give you some scope to adjust Castor by a degree or two by moving the upper and lower bones backwards and forwards, and then use washers or spacers to pinch the crush tubes.
From personal experience I've found that the 'whack with a big hammer' approach will get the wishbones in and is great if you
don't want your suspension to move up and down a lot or in a predictable manner....... and you wonder why people post questions asking why
Caterhams handle better than Locosts!
I'd seriously consider getting it sorted out properly........ MKs solution is, with the greatest respect, complete cr*p in a 'I can't
be bothered, please go away' stylee - they'll be telling you next that 'they're all like that mate'
For what its worth, Beddows is spot on.
Suspension has to fit properly to work properly, end of.
My experience of putting them on the MK is that you will need to push pull the bones by hand to get them in. You shouldn't need a hammer!
I would not get to bothered about it so long as they don't bind once bolted up, with washers to take up any space in the brackets. You have to
remember that even though they are jigged the wishbone will distort when welded, and this is why they don't quite fit...
Beddows: Not sure I agree so long as nothing binds, maybe for race use yes, but you would then go for spherical bearings, lots of adjustment and you
then get all the trouble they have with them wearing out etc. Also how can you possibly weld a wishbone without 2-5mm of distortion, I guess you could
braise them?
Dan
[Edited on 26/9/07 by Bluemoon]
[Edited on 26/9/07 by Bluemoon]
Thing is though they probably will bind slightly to a differing degree at different points of travel.... personal experience again I'm afraid
!
Ok, I'll admit if you hadn't driven a properly set up 7 with suspension that worked as it should then you'd probably be non the wiser
and think it was a great handling car. Why not do the job properly though and actualy have a great handling car? 
There will be loads of people with suspension like this and I bet some of them have bought expensive hi spec dampers as well.... which would have been
a bit of a waste of money if you think about it.....
I'm not having a go at MK in particular because I know they're not the only offender but if some Locost type chassis manufacturers can
produce a chassis with brackets the wishbones fit into without the use of a big hammer why shouldn't everyone? 
quote:
Originally posted by BenB
It's complicated re the crush tubes eh?
I know the logic is that hard plastics will be able to rotate around a crush tube (therefore you want a crush tube slightly longer than the bush) but if the rotation is free and without restriction why are you advised to not tighten the bolts up until the car is on the ground and weight-bearing?
My MK brackets and wishbones weren't quite as bad as that but I had to bend/pack them with washers none the less.
I've been over to MK approximately 10 times and not once have I been given the impression that they are a 'precision' engineers. Take
for example their modification of my steering shaft that I pulled out of a scrap yard the same day (mine had power steering). They simply cut it down
with a chop saw and welded it back up with no preparation to either surface, just welding through all the grease, mud and rust that had build up over
24 years and 163,000 miles.
Also, one of the diagonal tubes on my chassis in the engine bay is only attached at one end - If this was missed during manufacture, quality control
and powdercoating, what else has potentially been missed?
What Mike RJ said is correct, metallastic bushes should be tightened only once in their weight bearing position. A poly bush will not cope with shear
forces it will simply tear itself to bits in a very short time (like about 10 miles). They are most definitely designed to rotate about the
crush tube, hece the crush tube is longer than the outer tube + bushes.
If you are going to make these wishbones fit rather than getting the brackets moved I would suggest you remove the polybushes and grind down the outer
edges of hte wishbone tubes until the bushes and wishbone fits the brackets properly, then use large/penny washer to space out the slack on the inner
edges. At least this way, assuming nothing's twisted the suspension shouldn't bind up on you and should fit correctly even if not how it
should have done from the factory.
As rightly said above don't just hammer it together as something will be at the wrong angle and the suspension will be compromised in some way
leading to imperfections in the handling.
Ned.
You're not looking for a lot - I would just "cold set" - bend the wishbone until it slips in. Does your bench vice open far enough?
Not exactly right but it will work.
Looking back at the pic now, seem those front brackets may just save you the trouble and drop off all by themselves - Are they all like that?
Fred W B
[Edited on 26/9/07 by Fred W B]
quote:
Originally posted by Fred W B
Looking back at the pic now, seem those front brackets may just save you the trouble and drop off all by themselves - Are they all like that?
Hi well it still amazes me that people think that this sort of tolerance from certain manufacturers is actually acceptable even on the basic parts of
the cars.
Lets just hope that some of the recent price rises that most of the manufacturers have done over the recent past will mean that they can now afford to
take a bit more time when manufacturing to bring the quality up on the basic fit of certain parts .
Espesialy when for little more money you can move up in to the world of kitcars where the quality is much higher. Makes westfields seem quite cheap
when you consider the quality.
cheers matt
Polybush just replied to say
The crush tube should be clamped tightly in all cases so it doesn't rotate on or wear the bolt it rides on.
Don't worry about the Polyurethane wearing out - it has excellent abrasion resistance and will last for a long time in comparison to almost any
other material you care to name.
To get the best life out of your Polybushes, assemble them dry (no oil or grease) so they grip the tubes and housings rather than move inside them, so
most movement is taken up in the material, rather than in friction and wear.
Best regards
Ian Dickin
Product Manager
Polybush
this is why i take the diy approach at least then it you f**k it up the first time you can do it right the second lol or third time lol
quote:
Originally posted by BenB
To get the best life out of your Polybushes, assemble them dry (no oil or grease) so they grip the tubes and housings rather than move inside them, so most movement is taken up in the material, rather than in friction and wear.
If polybushes are very tight, and you prefer not to grease them, you will find they soften up nicely in hot water and will assemble much easier.
Going back to the original question - I agree with the comments above! Wishbones will distort when welded but not to that degree, and the brackets do
look very light given the accurate location and heavy loading involved. I would advise taking the time to correct it now, rather than hoping
it'll be alright when assembled.
Good luck,
Dom.
Just another comment, I would (or maybe should?) be very suprised if a manufacturers wishbones were to distort during manufacture. You'd hope a
good manufacturer would have a decent jig where the bush tube and balljoint mounting face are bolted or clamped in place whilst they are welded so
there should be no distortion of these critical points on the wishbones.
I am not havng a dig at mk in any way, just commenting on the original question asked in this thread from the pictures given.
IMHO..
Ned.
[Edited on 26/9/07 by ned]
I have to say that all of this surprises me.
The fit of the bones to the chassis, the way the brackets are attached to the chassis, and the attitude of the manufacturer.
It's certainly true that it really isn't ideal - any of it.
Is it really so much more difficult to get it really right than sort of almost right and just hammer it in the rest of the way ?
I really can't see Westfield or Caterham supplying parts like that - or the owners accepting such a standard.
As I said, I'm genuinely surprised.
quote:
Originally posted by BenB
It's complicated re the crush tubes eh?
I know the logic is that hard plastics will be able to rotate around a crush tube (therefore you want a crush tube slightly longer than the bush) but if the rotation is free and without restriction why are you advised to not tighten the bolts up until the car is on the ground and weight-bearing? That would suggest the bush is also clamped at a neutral setting and the resiliance of the bush to twisting is used....
PS if you assemble them dry, so they grip to limit the sliding, as polybush suggest, then they will creak like fcuk, as the polyurethane grips and lets go.
I cant believe that there are still people getting this bush thing wrong.
MikeRJ is correct. how the F*** can it be any other way.
Steve.
Hi i think there is quite some confusion between what is a polly bush. IE superflex type bushes and what the locost industry are using wich is just a
cheap general bush that was never desighned to be used as a suspension bush.
cheers matt
quote:
Originally posted by procomp
Hi i think there is quite some confusion between what is a polly bush. IE superflex type bushes and what the locost industry are using wich is just a cheap general bush that was never desighned to be used as a suspension bush.
cheers matt
Sorry but back to the original posting and I'm astounded that so many of you think the tolerance on the brackets can be sorted by a good
hammering. The grind away the bush till it fits is a better idea but the real issue is why the Fcuk are any of you prepared to accept shite
workmanship like this when you've paid good money for it to be correct??
I remember a post not so long ago when a certain chassis was an exception to the usual good quality many of you have experienced. Now we see a repeat
of much and such the same.
My advice would be to get them to sort it PROPERLY and at their expense. It is a critical part of the car and should not be put under additional
strain by hammering it in to fit. All IMHO of course.
quote:
Originally posted by omega 24 v6
..................My advice would be to get them to sort it PROPERLY and at their expense. It is a critical part of the car and should not be put under additional strain by hammering it in to fit. All IMHO of course. [/quote
^ ^ ^ ^......... Spot On....
Also IMHO ......
Fozzie
kb58 - 27/9/07 at 01:10 PMquote:
Originally posted by BenB
Polybush just replied to say
The crush tube should be clamped tightly in all cases so it doesn't rotate on or wear the bolt it rides on.
Don't worry about the Polyurethane wearing out - it has excellent abrasion resistance and will last for a long time in comparison to almost any other material you care to name.
To get the best life out of your Polybushes, assemble them dry (no oil or grease) so they grip the tubes and housings rather than move inside them, so most movement is taken up in the material, rather than in friction and wear.
Best regards
Ian Dickin
Product Manager
Polybush
About the bushings, think about how it all comes together and it makes sense. The crush tube is there to prevent the bolts from tightening up everything so that nothing moves (and also bending the brackets). Therefore, the crush tube does not move once tightened down. The A-arms do move, so there's only two places where the bushings can slide: between the bushing and the A-arm, or between the bushing and the crush tube. Since there is much more surface area between the bushing and the A-arm, it will be more resistant to slipping there, so all slipping - pivoting really - occurs between the bushing and the crush tube. You MUST have the crush tube!
kb58 - 27/9/07 at 01:14 PMAbout the A-arms not fitting, anyone who thinks heat distortion can't cause that hasn't welded the inside corners of tubes! That said, heat distortion is very well known, so it's no excuse here. If nothing else, the welding jig can space the arms slightly further apart so that it's perfect once they pull in towards each other. These A-arms simply aren't made very well.
procomp - 27/9/07 at 01:46 PMHi yes obviously the wishbones move when welded. But shurley the manufacturer should make shure that it will fit back in the jig as such before letting them out into the market place.
But the main problem is the fact that if you take some of the manufacturer's and acurattly measure the tolerance of the brackets and there position you would seriously wonder if they are actually using jigs at all. Unless 1/2 inch tolerance is what they call acceptable these days.
Also if you investigate further you will find that such poor tolerance's are over the whole car. Hence there are cars out there with upto an inch difference in the wheelbace either side.
However this level of tolerances is obviously accepted by many owners because thier manufacturer says " they are all like that. And we have a reputation for good handeling cars " .
It really is about time that some of the manufacturers decide to get thier act together and stop BS ing thier customers. And also that people building cars from whichever manufacturer started taking some of the basics a bit more seriously instead of just accepting the BS they are told. And realise that in the larger world of kitcars these sort of tolerance levels are just not acceptable these days.
PS in reply to one email i recived. No i am not soley talking about one paticular manufacturer but a few of them.
Cheers matt
Sorry rant over
MikeR - 27/9/07 at 01:50 PMIts times like this i'm glad i made my own chassis.
Yeah i'm having real hassle getting my head round problems that bought chassis would just be done (like how far to make the spacer for the clutch cable to) but at least i know i spent a year scratching my head over the front suspension before i realised my jig was 5mm out, remade it and welded it all together. In fact i think i am too an*l as i'm replacing my capri axle due to being 3mm out on a mounting bracket (plus the escort is lighter).
Fred W B - 27/9/07 at 01:59 PMA mate of mine once said to me the beauty of doing stuff yourself is that you can do it to your own standard.
That said, thats why we take years to build a car while others take weeks, or days? - even hours?
OT but the benchmark for a tintop nowadays is something like 20 odd assembly labour hours
Cheers
Fred W B
zilspeed - 27/9/07 at 04:18 PMIt almost makes me glas that my old tub (pictured left) uses a bolt on assembly from the donor.
A fairly well regarded set up admittedly.
D Beddows - 28/9/07 at 11:19 PMAside from all the above issues.....nobody has mentioned that on a purely practical level if you install the wishbones with a big hammer you'll find that, because you've bent them, the bolt holes on the brackets don't line up any more.......and the bolts wont fit through.....
MikeR - 29/9/07 at 12:01 PMah, but if you put a bolt through when you hit the wishbones then they'll stay lined up.......
plus the bolt holes will have been drilled bigger to take this into account!
(tongue firmly in cheek)
Syd Bridge - 29/9/07 at 04:39 PMquote:
Perhaps a market possibility for Superflex et al to clone the hard plastic bushes using their own material? I think people would buy them if they didn't charge ridiculous amounts for a set.
You might look at SuperPro bushes, they do just as you have suggested, and have done for many years. And they're Aussies as well! They have a very good UK agent, who is a joy to do business with, and really knows his stuff, and will search out any sized bush you ask for.
They do a nice bush to replace the Triumph Y419's, as mentioned in The Book. I'm putting them on the rear of the racers. Also do a TVR bush that I use for gearbox and engine mounts, that fits inside 1.25" OD 10G tube.
http://www.superpro.eu.com/
Cheers,
Syd.
[Edited on 29/9/07 by Syd Bridge]