simonr Posted September 5, 2013 Share Posted September 5, 2013 One of my 'little experiments' replaced the rear radius arms with electric linear actuators which were servo controlled. The original idea was to counter axle steer on articulation, but it worked fairly well to reduce the turn circle. It felt very odd to drive though as it was always (deliberately) crabbing on steer which made it difficult to know if the back end had lost traction as it felt the same as the back starting to drift! Needless to say, it didn't make much of a 'product'. Offset on the springs wasn't a problem. If you consider the offset when the vehicle is articulating - the springs usually stay attached. The amount of offset required for steering doesn't make much odds for standard springs so long as they have retainers top & bottom. Si Quote Link to comment Share on other sites More sharing options...
Jamie_grieve Posted September 5, 2013 Share Posted September 5, 2013 Coil over shocks would be a good solution The increasing angularity of a vertical suspension member from a turn pulling the spring elements out of line would correspondingly decrease spring rate and reduce ground clearance meaning it would roll more on turns and if you were turning across a hill. Maybe not too much to be a problem with really long coilovers? I was thinking along the lines of a turning sprung sub frame adding weight and complexity for little gain or some kind of mad F1 style with bell cranks and horizontal suspension to maintain stability. I still think the central Boge type strut to maintain ride height and using the wheels at the other end to maintain stability would be the only practical way forward. The only advantage to this type of wheel movement would be on really uneven terrain or when bogged. It's just an interesting theoretical exercise really. Quote Link to comment Share on other sites More sharing options...
Jamie_grieve Posted September 5, 2013 Share Posted September 5, 2013 One of my 'little experiments' replaced the rear radius arms with electric linear actuators which were servo controlled. The original idea was to counter axle steer on articulation, but it worked fairly well to reduce the turn circle. It felt very odd to drive though as it was always (deliberately) crabbing on steer which made it difficult to know if the back end had lost traction as it felt the same as the back starting to drift! Needless to say, it didn't make much of a 'product'. Is axle steer on articulation always a bad thing? Having the back wheels rotate around the trailing arms might even help climbing obstacles sometimes and help with the wheels trying to turn at the same average speed as the fronts? What happens to the grip and drive line if the whole wheelbase was effectively changing? A back wheel getting stuffed up climbing something is moving away from the obstacle slightly and a drooping wheel is generally moving forwards and vice versa on the fronts. Do you think the actuators would maybe work better on the front than the rear? What kinds of forces were you subjecting the actuators too and did they handle it? Sounds like a really interesting project and fair play to you for getting out in the shed and doing it and not 'vapour building' like me!!!! Quote Link to comment Share on other sites More sharing options...
simonr Posted September 5, 2013 Share Posted September 5, 2013 I drove for a year on & off road with a load cell on one standard radius arm. The peak compressive or tensile impulse force measured was about 4 ton but the RMS load was 2.2 Ton. This was the data used to specify my X-Joints! I used actuators with a stationary weight limit of 3 ton - so not quite enough for the peak impulse (which I think was from hitting a tree stump) but just OK for normal on/off road usage. I used a hockey stick bush at one end and the standard axle bush at the other mounted in clevises. The ram would twist so the bushes hardly needed any rotational offset capability. The actuators were actually sold as window openers for big plate glass windows subject to high wind loadings. They were surprisingly good value too. I've used the same actuators to raise & lower the suspension by moving the top spring hanger up & down - and they were plenty strong enough for that! Si Quote Link to comment Share on other sites More sharing options...
o_teunico Posted September 5, 2013 Author Share Posted September 5, 2013 The changing wheel base would require some serious body cutting I didn´t thought about that...could be done enlarging rearwards the wheel arch, and incereasing the wheelbase=making turning radius worst. Only a real proto will show if the benefit of rear axle steering overcomes the dissavantages of longer wheelbase. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted September 6, 2013 Share Posted September 6, 2013 That system may be practical for axles fitted with dual wheels, but for single wheels, for all the extra complication, it would be better to just fit the bogie with a proper drive/steering axle at the back. Quote Link to comment Share on other sites More sharing options...
discomark10 Posted September 6, 2013 Share Posted September 6, 2013 That system may be practical for axles fitted with dual wheels, but for single wheels, for all the extra complication, it would be better to just fit the bogie with a proper drive/steering axle at the back Well said. Quote Link to comment Share on other sites More sharing options...
o_teunico Posted March 6, 2014 Author Share Posted March 6, 2014 Lowrider time! Quote Link to comment Share on other sites More sharing options...
Boris113 Posted March 7, 2014 Share Posted March 7, 2014 There's a thread on the third one here: http://retrorides.proboards.com/thread/40056 It was a while since I read it properly, but IIRC there was something pretty dubious about how the rear suspension was bolted to the axle. The original build thread (which I can't find now) was great, the attention to detail was quite something. The series 2 with red wheels that you posted has a porsche engine mounted in the rear also! Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted March 7, 2014 Share Posted March 7, 2014 It was a while since I read it properly, but IIRC there was something pretty dubious about how the rear suspension was bolted to the axle. Would that be this rather dubious spacer setup? Quote Link to comment Share on other sites More sharing options...
western Posted March 7, 2014 Share Posted March 7, 2014 god that's a scarey suspension attachment. Quote Link to comment Share on other sites More sharing options...
Nigelw Posted March 7, 2014 Share Posted March 7, 2014 That looks like nothing more than 2mm plate buckling under those U bolts Even looks like they welded the lower shock pin to it Quote Link to comment Share on other sites More sharing options...
Landy-Novice Posted March 7, 2014 Share Posted March 7, 2014 omg.. look at the spacers in between the spring and axle and the bump stops... comfortable ride anyone? Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted March 8, 2014 Share Posted March 8, 2014 omg.. look at the spacers in between the spring and axle and the bump stops... comfortable ride anyone? I somehow doubt it was built to go any further than around the block on a smooth surface. I'm actually surprised vehicles like this are permitted to go anywhere near a public road ! How did the builder of the truck cab one get that rusty appearance on alloy panels? Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted March 8, 2014 Share Posted March 8, 2014 It's proper rust Bill, the paint contains iron powder. http://www.rustypaint.co.uk/ Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted March 8, 2014 Share Posted March 8, 2014 It's proper rust Bill, the paint contains iron powder. http://www.rustypaint.co.uk/ I take it by the rusty streaks visible on the front of the wings that the iron oxide is still corroding, so I wonder if there is also the 'galvanic' (electrolosys) corrosion between the iron and the alloy panels, than eats away the alloy ? Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted March 9, 2014 Share Posted March 9, 2014 I think you'd be right there Bill, unless they give all the panels a very good spray job before the rustypaint to ensure isolation. Not sure why anyone would want to spray rust on ..... now if there was only a simple spray that just made it disappear... Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted March 9, 2014 Share Posted March 9, 2014 Not sure why anyone would want to spray rust on ..... now if there was only a simple spray that just made it disappear... First to invent that spray will be an instant millionaire. Quote Link to comment Share on other sites More sharing options...
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