View previous topic :: View next topic |
Author |
Message |
arreff77 Articulating
Joined: 03 May 2009 Odometer: 992 Location: porthleven cornwall
|
Posted: Wed Feb 26, 2014 6:58 am Post subject: 4 wheel steer 90 based tube challenge truck.
|
|
|
I might be starting a new build based around around a 90. The plan is 100 inch wheel base, tube chassis and body. Full hydro steer not sure whether to use hydro winches or 8274's. The plan is to use if I can find any, Salisbury axles front and rear. Hoping to use a control system based around the 4 wheel steer from a Tele handler to control the steering, there by giving front only, rear only, crab steer and small radius steering. I should be able to make it self center as well then. It's a very loose idea at the moment.
So I've got a question before I start collecting parts and donor vehicles. Fabrication aside as the swivels on the landy axle bolt on I should be able to flip the axle to get the diff offset correct them bolt the swivels on to get the king pins in the correct orientation. I still want to use the the three link on the rear.
Answers on a post case please.
Many thanks Ben.
__________________________________ welcome to the dark side, we have cookies. |
|
Back to top |
|
|
|
ash awbery Just got MTs
Joined: 28 May 2008 Odometer: 208 Location: reading berkshire
|
Posted: Wed Feb 26, 2014 8:59 am Post subject:
|
|
|
Hi, if your flipping the axle the diff will have opposite rotation? Are you using a different transfer case? It might be a better idea to re tube the axles if you using salisburys and swap left to right rather than trying to flip (unless you go for standard LR axles then flipping would probably be easier. Sounds a cool build any way
Ash
__________________________________ il fix it when the noise is louder than the radio |
|
Back to top |
|
|
arreff77 Articulating
Joined: 03 May 2009 Odometer: 992 Location: porthleven cornwall
|
Posted: Wed Feb 26, 2014 10:07 am Post subject:
|
|
|
Thanks Ash, I've yet to get anything for the build just thras out ideas. Would I be not be able to rotate the diff to get the rotation correct?
__________________________________ welcome to the dark side, we have cookies. |
|
Back to top |
|
|
ash awbery Just got MTs
Joined: 28 May 2008 Odometer: 208 Location: reading berkshire
|
Posted: Wed Feb 26, 2014 10:19 am Post subject:
|
|
|
A Salisbury axle is a bit like an American Dana axle (I think it does actually used a Dana 60 ring and pinion) so the diff housing is part of the axle. So I might be better to remove the axle tubes front the diff casing and swap them over. The only thing with a Salisbury is they are very heavy and although the diff is strong I don't think the CVs are any different to 110s? So the Weight might not be worth the strength?
In a standard axle the diff is separate so you can just turn the diff (with a bit of work) and the as you say flip the swivels to correct the king pin inclination.
Many times I have played with a tele handler and thought how good there steering system would be in an off roader
Ash
__________________________________ il fix it when the noise is louder than the radio |
|
Back to top |
|
|
nj111 Just got MTs
Joined: 15 Dec 2010 Odometer: 166 Location: Forest of Dean
|
Posted: Wed Feb 26, 2014 7:26 pm Post subject:
|
|
|
Sounds great, could have a lot of potential there. Don't they often use a front R Rover P38 axle and flip it upside down for rear steer? as the diff's are offset the opposite side on P38 so then offset and rotation both come right. Others will know more far more than me on this though!
|
|
Back to top |
|
|
Little Tank Just got MTs
Joined: 22 Feb 2009 Odometer: 389 Location: launceston
|
Posted: Wed Feb 26, 2014 7:36 pm Post subject:
|
|
|
nj111 wrote: | Sounds great, could have a lot of potential there. Don't they often use a front R Rover P38 axle and flip it upside down for rear steer? as the diff's are offset the opposite side on P38 so then offset and rotation both come right. Others will know more far more than me on this though! |
I'm pretty sure you can get reverse cut ring and pinions for precisely what your doing.
|
|
Back to top |
|
|
teamidris Mud Obsessed
Joined: 24 Feb 2008 Odometer: 3372 Location: Staffordshire UK
|
Posted: Wed Feb 26, 2014 7:59 pm Post subject:
|
|
|
We believe you drive a lot harder forward than backward, and so Terry Winchman concluded that my 4x4x4 idea was silly
Although I may not have the cash, the time, the facilities or any real need, I still think rear steer would be fun So I was thinking the rear steer should only turn half as far as the front, so the CV's balls are always most of the way in when you hit the angry pedal.
I was driving a tele handler the other week with a mechanical change over valve. It let you force the issue in a way the electric valved JCB system didn't. Plus its mud friendly.
__________________________________ https://m.youtube.com/channel/UC3l3zoaCabKrgBSULSV1YgA |
|
Back to top |
|
|
Xpajun Mud Obsessed
Joined: 22 Sep 2008 Odometer: 3245
1988 Mitsubishi Shogun
|
Posted: Wed Feb 26, 2014 8:14 pm Post subject:
|
|
|
teamidris wrote: | We believe you drive a lot harder forward than backward, and so Terry Winchman concluded that my 4x4x4 idea was silly
Although I may not have the cash, the time, the facilities or any real need, I still think rear steer would be fun So I was thinking the rear steer should only turn half as far as the front, so the CV's balls are always most of the way in when you hit the angry pedal.
I was driving a tele handler the other week with a mechanical change over valve. It let you force the issue in a way the electric valved JCB system didn't. Plus its mud friendly. |
I think a lot of people think ones development ideas are silly - if only this type of person existed in the world we still wouldn't have the wheel.... think about it
|
|
Back to top |
|
|
Little Tank Just got MTs
Joined: 22 Feb 2009 Odometer: 389 Location: launceston
|
Posted: Wed Feb 26, 2014 8:34 pm Post subject:
|
|
|
Xpajun wrote: | teamidris wrote: | We believe you drive a lot harder forward than backward, and so Terry Winchman concluded that my 4x4x4 idea was silly
Although I may not have the cash, the time, the facilities or any real need, I still think rear steer would be fun So I was thinking the rear steer should only turn half as far as the front, so the CV's balls are always most of the way in when you hit the angry pedal.
I was driving a tele handler the other week with a mechanical change over valve. It let you force the issue in a way the electric valved JCB system didn't. Plus its mud friendly. |
I think a lot of people think ones development ideas are silly - if only this type of person existed in the world we still wouldn't have the wheel.... think about it |
Yep agreed, most wouldn't try something different, give it a go and see what happens. I shall be doing similar towards end of the year when I start a new build from scratch.
|
|
Back to top |
|
|
arreff77 Articulating
Joined: 03 May 2009 Odometer: 992 Location: porthleven cornwall
|
Posted: Wed Feb 26, 2014 8:56 pm Post subject:
|
|
|
Little Tank wrote: | Xpajun wrote: | teamidris wrote: | We believe you drive a lot harder forward than backward, and so Terry Winchman concluded that my 4x4x4 idea was silly
Although I may not have the cash, the time, the facilities or any real need, I still think rear steer would be fun So I was thinking the rear steer should only turn half as far as the front, so the CV's balls are always most of the way in when you hit the angry pedal.
I was driving a tele handler the other week with a mechanical change over valve. It let you force the issue in a way the electric valved JCB system didn't. Plus its mud friendly. |
I think a lot of people think ones development ideas are silly - if only this type of person existed in the world we still wouldn't have the wheel.... think about it |
Yep agreed, most wouldn't try something different, give it a go and see what happens. I shall be doing similar towards end of the year when I start a new build from scratch. |
The idea appeared in my head whilst messing about on a maker farm when I was doing a few repairs to his Tele handler. There was a load of stuff in the entrance to the barn (he'd cracked the boom head, don't ask how! so that needed to be welded up) it just surprised me how much maneuverability he gained at altering the steering configuration. I know it's something that would probably be used only occasionally but I think would be very useful when needed rather that having to shunt.
Having had a look under a landy in work today I think that using a standard front axle would be easier to rework and probably easier to get.
Team idris what kind of handler was it? The jcb and Manitou ones I've used I think are electronic type which was what I'd been basing my thinking on. The other reason I'd thought of this system was it's ability to lock out the rear steer incase I fancy trying to put this thing though an iva/sva or what ever it's called. If a telehandler can be road legal why not a all steer buggy.
__________________________________ welcome to the dark side, we have cookies. |
|
Back to top |
|
|
|
nj111 Just got MTs
Joined: 15 Dec 2010 Odometer: 166 Location: Forest of Dean
|
Posted: Wed Feb 26, 2014 10:49 pm Post subject:
|
|
|
arreff77 wrote: |
If a telehandler can be road legal why not a all steer buggy. |
To satisfy VOSA you must have a mechanical link in the steering, even though there are thousands of tractors , telehandlers, dumpers etc etc running around quite safely without this (and at 50k plus these days) , they are in a different taxation class. I think you will find those are the rules and if you look even HGV's have steering boxes.
About 20 yrs ago my father had a honda prelude with rear wheel steer, it only steered a few degrees but that made a massive difference for parking. Not sure how the system worked and I think the control was different at speed. The point is as teamidris says you may not need too much input at the rear to make a massive difference to turning but I think you will have to forget using it on the road. Nick
|
|
Back to top |
|
|
Eclipsed4ever Just got MTs
Joined: 05 May 2012 Odometer: 190 Location: Hereford
|
Posted: Thu Feb 27, 2014 9:30 am Post subject:
|
|
|
I would of thought getting something like this on the road could be a bit of a mission. Possible if you could fit a mechanical lock out mechanism on the rear perhaps?
The have been several cars in the past with 4ws. Preludes and Nissan 300zxs have both used this successfully. Even at speed the systems were active. It's a funny sensation as it feels the back end is stepping out but it's not. The extra corning ability is very impressive and you can really sick it round the bends. The Nissan used an electronically operated spool valve to drive a rear steering rack, I'm fairly certain the prelude used an electronic mechanism.
In terms of controlling your rear axle, have you considered going for fully independent control? You'd be surprised just how intuitive it is to control. I use a standard manually operated proportional valve For my rear steer. It allows quick changing from normal/rear only/crab/4ws. To me for the amount of control it gives you and for the simplicity Of the system it's the best way forward. There are a reasonable amount of eurotriallers using the telehandler style valves successfully. Depending on your target type of event, if you can stop and adjust axle positions then you'll be fine. You don't want to get stuck with one axle one was and the other the other coming up to a gate if your trialling though.
__________________________________ 2.2 Vtec 4WS Single Seater - aka Screamer - UK Champion 2013 + 2014
3.0lr V6 4WS - Screamer 2 - UK Champion 2015 + 2016 + 2017
Eurotrial 2nd in Prototype Class 2018
https://www.facebook.com/ScreamerOffroad |
|
Back to top |
|
|
arreff77 Articulating
Joined: 03 May 2009 Odometer: 992 Location: porthleven cornwall
|
Posted: Thu Feb 27, 2014 8:48 pm Post subject:
|
|
|
I'd thought about being able to lock out the rear for road use, possibly using a system similar to that of a cranes slew lock. Although I'm not sure how I could make it a fail safe that meant it would need to be engaged to drive on the road.
I have contacted vosa to try to clarify the issue, not holding my breath for a favourable answer though.
Team idris I'd also thought about the amount of steep that I'd need, I think half the lock of the front axle would be ample. Anymore and I think it would turn too tightly although it would be nice to have a proper crab steer set up and to have rear steer only at full lock. So would like to find a way of limiting the rear steer when in 4 wheel tight radius mode.
I realise that what I'm trying to achieve may be near impossible if not completely. Which is why I'm trying to thrash out the idea. It may be that the 4ws never makes it or I have 4ws but never goes on the road.
__________________________________ welcome to the dark side, we have cookies. |
|
Back to top |
|
|
teamidris Mud Obsessed
Joined: 24 Feb 2008 Odometer: 3372 Location: Staffordshire UK
|
Posted: Fri Feb 28, 2014 7:08 pm Post subject:
|
|
|
The valve set up I liked was Merlo. You could crab with the back axel partly set over, which was great for working a basket-platform down the side of a shed with my brother nailing up cable. JCB wouldn't have done it so well, as the rear re-sets every steer change. The Merlo was just a mechanical lever.
For a half-steer rear it could be as easy as having twice the ram area? Saves altering the swivel arms.
If you use a double ended ram it replaces the track rod. So de-piping the ram and dropping an axel terminated drag link to the swivel arm would lock it. You would have to ball joint split it every time though?
Or you leave the track rod as is (maybe sumo) and have one ram to one drag link arm. You then run a fixed drag link from axel to the other hub for road use. There does seem to be a hate for the drag link, which I can understand, but a lot of plant ran a track rod and one ram okay.
I think for a road-use 4x4x4 you will eventually come back to a standard rover front end and a joystick rear that can be mechanically locked. Or, to look at it from an official MOT perspective; "Is Locked and safe" and can be easily mechanically changed at an event to allow the rear steer. Which is going to involve spanners and maybe a ball splitter? Because 10 mins work at an event is going to save a lot of approval agro
__________________________________ https://m.youtube.com/channel/UC3l3zoaCabKrgBSULSV1YgA |
|
Back to top |
|
|
RL12 Just got MTs
Joined: 22 Aug 2010 Odometer: 297 Location: Devon/Shropshire
1987 Daihatsu Fourtrak
|
Posted: Thu Mar 06, 2014 7:53 pm Post subject:
|
|
|
What about having standard steering on the front but attaching a double ended ram to the back of the front axle, plumbed into a double ended ram on the rear axle to steer it.
You could have a tap to divert oil in various ways to get different steering modes, Or recirculating the oil into the same cylinder and locking off the rear axle for 2ws.
Rear lock could we be some sort of simple pin on a spring with an electric solenoid to lift it out when off-roading
Let me know if this doesn't make sense, I haven't really explained it very well..
__________________________________ Fourtrak/LJ70 project
Youtube: FourtrakRich |
|
Back to top |
|
|
unimogler Winch Assistant
Joined: 17 Mar 2008 Odometer: 93
|
Posted: Thu Mar 06, 2014 9:09 pm Post subject:
|
|
|
hi mate, must be a good idea, I built one last year!!! the fellow who said use a p38 front is spot on, and use a disco 2 front in the front. that way you don't have to cut the axle case and turn the pumpkin over or weld the ends on to a back axle from a front, both of these jobs require a jig of some sort and lots of carful measurement, also the later axles have cv boots which mean a lot lot less time and mess to change a shaft or cv or diff. an added bonus is that p 38/ disco 2 axles are dirt cheap. arb lockers will transfer to the later cases so no problem there. if you use standard rear suspension set up remember that front axle diff is a different offset to back axle. we used regular rams about 8" stroke 11/4" rod, and replaced the track rods with 3/4" rodends. a full hydro winch set up means you can power at least one ends steering from the big pump, we use the pump from a 4.6v8 to power the front so if one system dies we can still steer the other end. at 100" wheel base you can move engine back to the bulk head and use standard disco 2 propshaft. hope this is of some help, not many do this kind of stuff but its well worth it, if only for the looks you get as you cruise through the pit at a challenge side ways. fred.
__________________________________ why worry about tomorow,after all today is only the tomorow you were worried about yesterday. |
|
Back to top |
|
|
Eclipsed4ever Just got MTs
Joined: 05 May 2012 Odometer: 190 Location: Hereford
|
Posted: Thu Mar 06, 2014 9:10 pm Post subject:
|
|
|
You'd want some pretty monster power steering for that set up RL12!
__________________________________ 2.2 Vtec 4WS Single Seater - aka Screamer - UK Champion 2013 + 2014
3.0lr V6 4WS - Screamer 2 - UK Champion 2015 + 2016 + 2017
Eurotrial 2nd in Prototype Class 2018
https://www.facebook.com/ScreamerOffroad |
|
Back to top |
|
|
arreff77 Articulating
Joined: 03 May 2009 Odometer: 992 Location: porthleven cornwall
|
Posted: Thu Mar 06, 2014 9:41 pm Post subject:
|
|
|
Right the idea has evolved slightly. I'm still sticking to the basic idea although for the moment trying to keep it road legal has gone out the window. Also rather than base it purely on a landrover I've also been thinking about my samurai and working around that as a platform to start from. Again it would be built from the ground up. Gonna go and look at p38 and disco 2 axles now. Oh and beaver tails too.
Unimogler do you have anymore info or pics?
Many thanks Ben
__________________________________ welcome to the dark side, we have cookies. |
|
Back to top |
|
|
teamidris Mud Obsessed
Joined: 24 Feb 2008 Odometer: 3372 Location: Staffordshire UK
|
Posted: Fri Mar 07, 2014 4:30 pm Post subject:
|
|
|
I like the Vitara and the way it climbs without boinging left and right like my RRC buggy. If I was 4x4x4 from nowt I'd weld two vitara front ends together. The simple chassis rails make that part easy. Then put a wiper motor on the rear ones steering rack. (Don't know nothin' about the rear prop shaft though. But it will need a transmission brake)
__________________________________ https://m.youtube.com/channel/UC3l3zoaCabKrgBSULSV1YgA |
|
Back to top |
|
|
Eclipsed4ever Just got MTs
Joined: 05 May 2012 Odometer: 190 Location: Hereford
|
Posted: Fri May 23, 2014 8:04 pm Post subject:
|
|
|
Any progress on this?
__________________________________ 2.2 Vtec 4WS Single Seater - aka Screamer - UK Champion 2013 + 2014
3.0lr V6 4WS - Screamer 2 - UK Champion 2015 + 2016 + 2017
Eurotrial 2nd in Prototype Class 2018
https://www.facebook.com/ScreamerOffroad |
|
Back to top |
|
|
|
|