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PostPosted: Fri Jun 25, 2010 10:08 am 
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I know independent suspension is all sexy and all that but has anyone considered using a one piece front axle?

It wouls simplify the pieces involved in the suspension and in getting everything to align.

Some of the Locosts use a solid rear axle, why not a solid front axle?

I am thinking of a Locost as a daily drive and not as a perfoemance vehicle, something funm to drive back and forth to work. Reliability being the main idea.


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PostPosted: Fri Jun 25, 2010 10:25 am 
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If you want it to ride more like a truck, I suppose why not...


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PostPosted: Fri Jun 25, 2010 11:19 am 
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I have both a Locost and a 32 Ford hot rod. The solid axle Ford doesn't ride that badly, but neither does it corner like the Locost. Both are a ball to drive around in but I wouldn't say that the Locost was any better over potholes than the hot rod. At least not because of the front axle alone. :)

Most of the handling shortfall on the 32 roadster is due to the transverse spring and split wishbone suspension. The lever shocks, the 46 ford steering box, and the 18" steering whell don't help either. Also, the car is not equipped with sway bars (but neither is the Locost). The rear end uses a triangulated four bar with coilovers, so it's actually more "modern" in execution than the front. But in spite of all that, the car does exactly what it was built to do - it is very quick in normal driving (nice torquey Chevy V8), is very comfortable, and looks darn good. It would be a better commuter car than the Locost, IMO.

Anyway, the solid axle can be a viable option and with proper locating methods could be a far better handling car than my traditional hot rod.


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PostPosted: Fri Jun 25, 2010 12:01 pm 
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gtivr4 wrote:
If you want it to ride more like a truck, I suppose why not...

I would guess this answer is about being flippant.
Sprint and midget cars get around quite nicely with a solid front axle and apparently they handle also. Like any other front suspension the setup will produce the final ride qualities you are looking for.
Honestly my thoughts building my car ran towards the solid axle.
What I hoped to accomplish was to beat the modern ricer technology with the old stuff but due to lack of backbone and a desire to punish myself in the design stage I caved and designed a independent.
Short answer, it can work quite well.

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PostPosted: Fri Jun 25, 2010 5:04 pm 
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Anyone know of a source or design for a solid axle? I know all about the machining end of things, but don't currently have a mill big enough to make an axle bigh enough for a car. (gokart - maybe...)

I am not looking for high performance, just good solid reliability. Since the wheels and A-arms can take a beating I was thinking that a solid axle would be more robust without adding complexity. I wold also like to go with a steering gearbox and not use a rack and pinion. Could possibly get quicker steering with the right choice.(as well as the fact that they last forever)


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PostPosted: Fri Jun 25, 2010 6:17 pm 
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kf2qd wrote:
Anyone know of a source or design for a solid axle?

Trailer axle?

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PostPosted: Fri Jun 25, 2010 6:23 pm 
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egoman wrote:
gtivr4 wrote:
If you want it to ride more like a truck, I suppose why not...

I would guess this answer is about being flippant.
Sprint and midget cars get around quite nicely with a solid front axle and apparently they handle also. Like any other front suspension the setup will produce the final ride qualities you are looking for.
Honestly my thoughts building my car ran towards the solid axle.
What I hoped to accomplish was to beat the modern ricer technology with the old stuff but due to lack of backbone and a desire to punish myself in the design stage I caved and designed a independent.
Short answer, it can work quite well.

There is no answer. If someone's okay with a stiff ride, they'll be just fine with a straight front axle. OTOH, someone expecting a Lexus LS460-quality ride won't be happy with any Locost no matter what suspension it has.

About sprint and midget cars - they ride on smooth tracks, not bumpy streets, so it's not a big deal. Also, they're classed such that everyone's on the same suspension, so there isn't even an option to be different.

About comparing the ride of a 1930's hot rod and a Locost, I'd guess that the hot rod would have a smoother ride simply because its sprung-to-unsprung weight ratio is more favorable. As was said, they're very different cars intended for different things, but if ride quality is what it's all about, independant suspension is where it's at. The OP might consider researching why cars went to independant suspension at the front in the first place. Better yet, try and get a ride in a lightweight straight axle car and see if it's tolerable. If it is, you're all set.

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PostPosted: Fri Jun 25, 2010 11:21 pm 
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kf2qd,

My problen is ever since high school I have always wanted to build a T-Bucket Roadster. I am a Boilermaker/Shipfitter/Welder by trade so building the frame on anything is not a big problem. A while back I bought my Mom a 2005 Lincolin Town Car with a few miles on it. I told Mom that the car was cheap enough at $4500.00 that even if I had to change the motor it was still a good deal. The car rattled a bit only when it first started is why I was concerned. Found out later that the car had been sitting on the lot for five months unstarted. After a week starting and driving the rattling went completly away. But by this time I had already been doing research on Lincoln motors and fell in love with the four cam 32 valve design. Couple days later I find a local guy selling a motor and transmission out of a 96 Lincoln Mark VIII for real cheap. As a kid I lived next door to this guy and he has always been into hot rods and BIG TIME into them. So I bought the motor and trans and was looking into building my dream car when I found all this stuff on these locost cars. I just love the body style of the locost because it is so close to looking like a Track-T roadster. The frames on the locost is what I like the most. I also like the solid axles of the T-Buckets and Track-T's though and have thought a lot about putting solid axles in a Locost. I am more the Drag race kinda guy so solid axles would do good in a locost body and frame. I have already decided to use a 9" ford straight axle in the rear of my car. All I can say is one of those dropped and polished stainless tube axles from Speedway would look reeeeaaaal good in a locost car. Everyone I have talked to have said the straight axles in T-Buckets ride pretty good when set up with coilover shocks. Love to see it!


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PostPosted: Sun Jun 27, 2010 2:54 pm 
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kf2qd wrote:
Anyone know of a source or design for a solid axle?
http://www.speedwaymotors.com/Model-A-Ford-4-Bar-Axle-Kits-for-Chevy-Spindles,19971.html

Also in their latest catalog starting at page. 20. It won't be low cost but the parts are available. But it would certainly look clean with push rods to inboard coil overs. You'd have to consider the drop of the axle so it doesn't hit the lower frame tubes.

I was also thinking of using a straight axle at one time using a 5 link system. Mostly to be different. And there is certainly less worries about the geometry (other than Ackermann).

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PostPosted: Mon Jun 28, 2010 9:23 am 
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If you're starting from scratch, I don't recommend the Chevy spindle version. The Ford spindles are more common and have a far greater variety of steering arm and brake options available, generally at a lower cost, too.

If you go searching, you'll probably find that Track-T roadsters are closer to Locost than T-buckets. Those buckets are kind of outlandish and not set up to do anything other than go straight. Track roadsters, OTOH, are race cars that were built for both road course and circle tracks. I can envision one built with a Locost style body instead of the usual 26-27 T roadster. With some of the Locost space frame grafted in, you could have a pretty capable chassis.

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PostPosted: Mon Jun 28, 2010 10:12 am 
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MustangSix wrote:
If you're starting from scratch, I don't recommend the Chevy spindle version. The Ford spindles are more common and have a far greater variety of steering arm and brake options available, generally at a lower cost, too.
Very true. I picked the Chevy illustration because it happened to have a 4 link setup. Most of the Ford pictures use the split wishbone setup which really isn't that good because something has to bend to allow for roll.

The main problem I see is the position of the axle itself in relation to the lower frame rails. The typical axles in the Speedway catalog have 3" to 6" drop near the kingpins. That will have the axle resting on the lower frame rail (unless you run a suicide mounting).

Assuming a 4" axle drop and taking measurements from my car with 22" tall tires and 5-1/2" ground clearance I come up with the C/L of a 4" dropped axle 1/2" above the upper surface of the lower tube and 10-1/2" from the lower surface of the upper tube. Not good at all since the axle tube itself would be resting on the lower tube. Or you would have to run much less ground clearance.

A straight axle should fit OK but with restricted clearance on the chassis rising. Sounds like a custom straight tube axle is required. A solid (forged) axle would really be -way- too heavy for a Locost.

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PostPosted: Mon Jun 28, 2010 10:48 am 
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Hairpins or split wishbones work fine with the I-beams. They will twist and actually act as a sway bar when set up that way. Tube axles don't twist and will bind unless you use a 4-bar.

For planning measurements, I have a 4" drop, I-beam Superbell on my 32. Running Ford spindles and 24" diameter tires, the center of the axle has 5" fo ground clearance. On a Locost-like roadster you would probably set up chassis so that the axle is ahead of the main chassis and would be allowed to droop below it.

Ford spindles are rear steer and Unisteer makes a nice R&P setup to cross steer a solid axle with no bump steer. I'd definitely use a four bar with coil overs and a panhard bar or on a car like this, maybe even a watts linkage. I have to research roll center calcs for straight axles.

The axle itself is not the heavy part. I don't think mine weighs over 40 lbs and a tube axle is going to be lighter. I think the GM brakes I used weighed more than the axle. I have those massive early cast iron calipers on large single piece 11" discs. That assembly with the spindle and brackets must be close to 50 lbs. You can get stuff that would be half that weight.

Maybe this thread ought to move to the non-traditional build forum........

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PostPosted: Mon Jun 28, 2010 11:17 am 
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often expressed opinion of many wrote:

About sprint and midget cars - they ride on smooth tracks, not bumpy streets, so it's not a big deal. Also, they're classed such that everyone's on the same suspension, so there isn't even an option to be different.



Sorry but Nah - Supermodified's have always ruled with beam over IFS and continue to do so including some very rough ovals (paved).

The very last car that Colin Chapman built (thats Lotus) before the rush for wings and downforce (1968) was a front and rear live beamed F2 car in his search for the ultimate in mechanical grip.
http://www.ultimatecarpage.com/car/1456 ... worth.html

Heres interesting reading for Locoster's of a successful Locost that was before the term Locost existed ....
http://forums.autosport.com/lofiversion ... 327-0.html
and a bit more here...
http://forums.autosport.com/lofiversion ... t5596.html

kf2qd, there is simply no better way to get 2 tyres on the ground for the bulk of the time and Egoman points mostly to why it's not common - lack of backbone along with the witchhunts that go with it. Do it and wait for the cries of "ride like a truck, unsprung weight" and my favorite "the inside will hit a bump and the outside tyre will lose traction" (forgetting to mention the bump needs to be 2 foot high).


Last edited by cheapracer on Mon Jun 28, 2010 11:27 am, edited 2 times in total.

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PostPosted: Mon Jun 28, 2010 11:24 am 
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MustangSix wrote:
I have to research roll center calcs for straight axles.
.


Nothing to know, use a Panhard or a Watts and the RC will be halfway on the Panhard rod or the central pivot for the Watts.

This is another advantage of a beam, you can make the RC have no lateral movement.


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PostPosted: Mon Jun 28, 2010 2:10 pm 
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cheapracer wrote:
often expressed opinion of many wrote:

About sprint and midget cars - they ride on smooth tracks, not bumpy streets, so it's not a big deal. Also, they're classed such that everyone's on the same suspension, so there isn't even an option to be different.



Sorry but Nah - Supermodified's have always ruled with beam over IFS and continue to do so including some very rough ovals (paved).

The very last car that Colin Chapman built (thats Lotus) before the rush for wings and downforce (1968) was a front and rear live beamed F2 car in his search for the ultimate in mechanical grip.
http://www.ultimatecarpage.com/car/1456 ... worth.html

Heres interesting reading for Locoster's of a successful Locost that was before the term Locost existed ....
http://forums.autosport.com/lofiversion ... 327-0.html
and a bit more here...
http://forums.autosport.com/lofiversion ... t5596.html

kf2qd, there is simply no better way to get 2 tyres on the ground for the bulk of the time and Egoman points mostly to why it's not common - lack of backbone along with the witchhunts that go with it. Do it and wait for the cries of "ride like a truck, unsprung weight" and my favorite "the inside will hit a bump and the outside tyre will lose traction" (forgetting to mention the bump needs to be 2 foot high).

Thanks for the backup......I think> :?: :?:

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