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Fabricated Uprights - Show Me Yours
43655 - 5/11/13 at 09:22 PM

Please!

really struggling with designing these, probably want to use a similar upright for front at rear.
I have a set of bolt on hubs at the moment (Golf MK4) although they don't actually match the driveshafts at the moment
Anyway I've looked at the two intersecting tubes method, regular welded assembly, CNC'd ally etc and not happy with any.
Want to be doing uprights and wishbones in work ready to go on the chassis when it's ready, but getting nowhere at the moment.
For reference the suspension looks like this at the moment http://tinyurl.com/lryvjhg (complete blank sheet self made chassis, 1800mm wide body, 16 or 17's[sorry!] )

I had a set of Pro Spindles, but the huge spindle didn't appeal anymore.
Will upload photos of my CAD attempts so far.

Basically I'd love to see what you guys have got/made for front and rear suspension
Cheers!

mark chandler - 5/11/13 at 09:34 PM

My rear ones, three bits of steel with the sierra hub machined down and welded in.

Description
Description

It's braced at the bottom with a bit of tube that a long bolt goes through which secures rose joints so it allows camber and toe to be set.

Cheap and cheerful, cortina at the front.

Regards Mark

atm92484 - 6/11/13 at 01:49 AM

I'm a bit partial to these front ones :
Partially completed
Partially completed 2
Awaiting reassembly

So far they've survived 4,000 miles which included a bunch of autocrossing on street tires, a few track days, and a season of autocrossing on 10" wide race slicks. They seem to work.

[Edited on 6/11/13 by atm92484]

ashg - 6/11/13 at 08:18 AM

those upper and lower front chassis pick-up points look somewhat inadequate

maccmike - 6/11/13 at 08:44 AM

Hi.
Word of caution.
Golf hubs wont suit a rearwheel drive configuration unless the rack is behind the the front axle line.
And they'll be big and heavy.

phelpsa - 6/11/13 at 09:20 AM

quote:
Originally posted by ashg
those upper and lower front chassis pick-up points look somewhat inadequate


You're joking?

v8kid - 6/11/13 at 11:34 AM

quote:
Originally posted by phelpsa
quote:
Originally posted by ashg
those upper and lower front chassis pick-up points look somewhat inadequate


You're joking?


No I don't think he is - not at all.

CNHSS1 - 6/11/13 at 12:32 PM

quote:
Originally posted by phelpsa
quote:
Originally posted by ashg
those upper and lower front chassis pick-up points look somewhat inadequate


You're joking?


look ok to me too, fronts possibly a tad longer than the norm, but looking at the orientation of the rosejoints its gonna be more track biased anyway. Nicely triangulate and beefy chassis so the mounts will become sacrificial in a race accident.

phelpsa - 6/11/13 at 12:32 PM

quote:
Originally posted by v8kid
quote:
Originally posted by phelpsa
quote:
Originally posted by ashg
those upper and lower front chassis pick-up points look somewhat inadequate


You're joking?


No I don't think he is - not at all.


That looks like 2" x 1" circa 3mm wall box section, you could hang a house off that.

v8kid - 6/11/13 at 01:18 PM

quote:
Originally posted by phelpsa
quote:
Originally posted by v8kid
quote:
Originally posted by phelpsa
quote:
Originally posted by ashg
those upper and lower front chassis pick-up points look somewhat inadequate


You're joking?


No I don't think he is - not at all.


That looks like 2" x 1" circa 3mm wall box section, you could hang a house off that.

leverage

ashg - 6/11/13 at 03:09 PM

exactly.....

atm92484 - 6/11/13 at 03:13 PM

quote:
Originally posted by ashg
those upper and lower front chassis pick-up points look somewhat inadequate


Someone questioned this on the USA board when I started the build - the vertical loading that bends the mount about its minor axis is extremely low. The only time it will exist is when the arm isn't in plane with the rest of the mount (IE suspension is in bump or droop). The rest of the time the mount is in tension or compression so length doesn't matter as long as it remains reasonable. There is also 6" of weld seam for each lower mount and a little over 4" for each upper mount; the stress where the mount attaches to the thinner chassis tube are is lower than typical.

In the end the bending force ends up being about equivalent to an average sized guy (around 150 lbs) standing on the mount. I did a bunch of "testing" before driving the car and it survived.

The upper mounts are even less of a concern since their loading is even lighter (less than 1/2 of what the lowers see). I would be more worried about the standard U style mounts that have a piece of 1/8" plate cantilevered off of the end of the tube with 2-4" of weld attaching them to the frame; we've seen enough of those fail from fatigue and I'm sure they are not very stiff to begin with.

I originally tapered the lower part of the forward section to match the nose. Had I bought the nose first and realized the actual shape, I would have made that tube straight and not worried about the mounts. Hind sight is 20/20 - doh.

[Edited on 6/11/13 by atm92484]

[Edited on 6/11/13 by atm92484]

ashg - 6/11/13 at 03:45 PM

well if you have worked it all out and accepted that it is ok i will question it no further

43655 - 6/11/13 at 05:48 PM

What's wrong with golf hubs, i literally only mean the bolt on section


atm92484, what are the ball joint assemblies used there? I was planning to use just sperical bearings with the housings they supply, and rod ends for the inside pivots but that's neither here not there.

Alright here's what I've got so far. Still needs steering arms and caliper mounts.
I don't really like putting all the load on a nut at the bottom, but then everyone using a tapered ball joint is basically doing the same?

atm92484 - 6/11/13 at 06:00 PM

No problem Ash - if my logic doesn't sound solid I hope someone points out the flaws.

They are these ball joints: http://www.summitracing.com/parts/afc-20034/overview/
With these threaded sleeves: http://www.summitracing.com/parts/afc-20043/overview/

[Edited on 6/11/13 by atm92484]

ettore bugatti - 6/11/13 at 08:04 PM

JBA Falcon are using some interesting uprights, using Vauxhall Astra hubs (my guess)

http://www.youtube.com/watch?v=EhCS5_-mur8
and
http://www.youtube.com/watch?v=8poTQ_9hvgU

v8kid - 7/11/13 at 09:05 AM

quote:
Originally posted by atm92484
quote:
Originally posted by ashg
those upper and lower front chassis pick-up points look somewhat inadequate


Someone questioned this on the USA board when I started the build - the vertical loading that bends the mount about its minor axis is extremely low. The only time it will exist is when the arm isn't in plane with the rest of the mount (IE suspension is in bump or droop). The rest of the time the mount is in tension or compression so length doesn't matter as long as it remains reasonable. There is also 6" of weld seam for each lower mount and a little over 4" for each upper mount; the stress where the mount attaches to the thinner chassis tube are is lower than typical.

In the end the bending force ends up being about equivalent to an average sized guy (around 150 lbs) standing on the mount. I did a bunch of "testing" before driving the car and it survived.

The upper mounts are even less of a concern since their loading is even lighter (less than 1/2 of what the lowers see). I would be more worried about the standard U style mounts that have a piece of 1/8" plate cantilevered off of the end of the tube with 2-4" of weld attaching them to the frame; we've seen enough of those fail from fatigue and I'm sure they are not very stiff to begin with.

I originally tapered the lower part of the forward section to match the nose. Had I bought the nose first and realized the actual shape, I would have made that tube straight and not worried about the mounts. Hind sight is 20/20 - doh.

[Edited on 6/11/13 by atm92484]

[Edited on 6/11/13 by atm92484]


Excellent! You can't beat sums and then some testing to check How did you calculate and check the braking loads by the way? 3g 750kg spread over two mountings that's around a tonne each I would expect some deflection at that load but perhaps its not significant possibly resulting in a bit extra toe out? I'd still check for fatigue cracks regularly.

Cheers!

v8kid - 7/11/13 at 09:12 AM

quote:
Originally posted by 43655
What's wrong with golf hubs, i literally only mean the bolt on section


Interesting do you have a weight for the golf hub/bearing assembly?

Cheers!

atm92484 - 7/11/13 at 03:09 PM

quote:
Originally posted by v8kid
Excellent! You can't beat sums and then some testing to check How did you calculate and check the braking loads by the way? 3g 750kg spread over two mountings that's around a tonne each I would expect some deflection at that load but perhaps its not significant possibly resulting in a bit extra toe out? I'd still check for fatigue cracks regularly.

Cheers!


I created a spreadsheet in Excel that allowed me to input the static weight, wheelbase, track width, CG height, weight, and lateral/longitudinal acceleration. From there it calculates the balljoint loads then the loads in each leg of each arm. I can size tubes, rod-ends, bolts, and other brackets from this data.

v8kid - 8/11/13 at 09:41 AM



I can weigh it this weekend if i remember. it's pretty average.
I plan to drill them for 5x114.7 too

Won't be using the outer part of the assembly in the latest hub design as you can imagine, just press the bearing in.

Whilst I'm here, does anyone know where I could find weld in ball joints? I'm sure it was on here i saw it. Or just go for spherical bearings?


Not seen weld in ones. Usually they are staked in with a press I should think the heat from welding would effect the liners

scimjim - 8/11/13 at 10:16 AM

quote:
I plan to drill them for 5x114.7....


Hopefully not?

ettore bugatti - 8/11/13 at 06:35 PM

Why not Jeep/Chrysler bolt-on hubs? These have 5x114.3mm as standard.

Used on TVRs, too
http://www.thetvrshop.com/TVR/Parts_details/TVR%20C0928/a|/Tuscan.htm

43655 - 9/11/13 at 08:50 AM

quote:
Originally posted by scimjim
quote:
I plan to drill them for 5x114.7....


Hopefully not?


Why not? It'll go inbetween 5x112 just fine
I'd like to have a fair bit of flexibility with wheel choice, but i need VAG hubs to mate up to the driveshafts (Audi gearbox)

Can't remember where i saw the ball joints I'm thinking of, but the outer was welded in, then the ball and 'bottom' went in from underneath

[Edited on 9/11/13 by 43655]