Jump to content

Recommended Posts

I feel it is about time the 'Forest Rover' was recreated, but with difflocks, power steer and a proper front suspension.

i'll grab the popcorn. :D

Share this post


Link to post
Share on other sites

It's just not getting any prettier is it?

I like my front suspension, very simple and reliable and you can hit things harder than with coils without pushing the radius arm through the out rigger.

No track rod under the axle to get pulled out of shape driving down to the shops or if a rabbit sticks his head up at the wrong time.
That said, I've got all the room in the world for a three link or a transverse leaf spring and I went as far as playing with a couple of tractor top links for the three point linkage. The Landies all wrong for the portal axles I have on the front as the diff is offset to the left by 100mm and it would be wasted on this thing.

All this started because I broke a rear leaf spring not because I really wanted to make a tractor. Seems to be I can't get a decent British made leaf spring until the end of September when the next load of steel comes from China or India because we can't make anything here any more. I could have got one in a blue box but did this instead to tide me over. I knew that building this monstrosity was ultimately less painful and cheaper and easier in the long run than putting a crappy Britpart spring on.

The forrest Rover was cool but 4 equal size tyres would be too easy. I was curious about the small front tyres with the big rear ones. It had a good bit of abuse today and the centre diff seems to have held together pretty good so far. Got the rear tyres down at 5 psi but you could still run over a coin and tell if it was heads or tails it's that stiff.

I made a press and put the tyres on 6.5" rims thinking they'd maybe flex a bit but not really, there's not enough weight on them.

1187109_622760207755566_1217694287_n_zps

Share this post


Link to post
Share on other sites

<iframe src="http://<iframe src="https://www.facebook.com/video/embed?video_id=442517142528651" width="1280" height="720" frameborder="0"></iframe><iframe src="https://www.facebook.com/video/embed?video_id=442517142528651" width="1280" height="720" frameborder="0"></iframe>

Can folks without a Facebook login see the video? I'm not sure how to link it.

Share this post


Link to post
Share on other sites

Bit of a thread resurrection here.

We dragged the poor old thing out the weeds there at the weekend, surprisingly it started on the first pull and made for some entertainment before sticking it in the shed for a wee makeover. I'm at home on leave for a week and wanted to do something with it. The plan is to stick a pair of Sumb axles on it to take decent sized tyres.The Sumb axles are because of easy Land Rover compatibility compared to the above mentioned TRM ones. The diffs on the Sumb axles can be configured for right hand drop and thus a reasonable amount of suspension travel can be created without excessive ride height due to engine clearance issues. The Sumb axles unlike the Unimog axles don't need a pinion conversion as the splines on the input are the same as the sliding part on a Land Rover prop shaft and also the yoke from a V8 Discovery slides right on there without even the need for a flange.

The plan is for a one link at the front and an A frame and trailing arms at the back. I doubt I'll have time to do the back this week but I hope to make progress with the front.

IMG_5784.jpg

IMG_5788.jpg

IMG_5789.jpg

IMG_5791.jpg

That's the axle mocked up at ride height.

I've shifted the track rod from the back to the front for now but I'll have to make steering arms to get the Ackerman angle happening again. Steering arms will be easy as the king pins are underneath but I doubt it'll happen this year. Same for a disc conversion too. I'll probably run cables for the diff locks and ditch the pneumatic setup.

I plan to go with mechanical steering just now but hydro is on the cards for later. If I go hydro I'll also ditch the panhard in favour of an A frame and lower links to raise the roll centre and keep the wheels away from the body and increase side slope stability.

Dramas just now are getting the front prop to clear the starter motor and making the one link a sensible shape.

The prop needs to be in two parts with a centre bearing and preferably with a CV joint at the transfer case. I was just looking at Disco 3 props on the web there which kinda have all the bits I need. The two piece prop is only because I want a sensible ride height and centre of gravity and my driving style likes up travel too.

Share this post


Link to post
Share on other sites

bill van snorkle, on 24 Aug 2013 - 02:53 AM, said:

snapback.png

I feel it is about time the 'Forest Rover' was recreated, but with difflocks, power steer and a proper front suspension.

i'll grab the popcorn. :D

:popcorn-and-drink-smiley-emotic

Lol, it's kinda heading that way.

IMG_5815.jpg

The poor thing's still not getting any prettier. One day I'd like to build something nice. Maybe with shiny bits like other people do.

I made a wee bit of progress but not as much as I'd have liked. I was a bit pathetic with my efforts this week. Feeble excuses aside at least the front axle's under the thing and it moves. I'm fairly pleased with the low rider stance as the last thing I want is something that has the centre of gravity of a monster truck. It sits almost level with my 88" posing as a 90. My 88" is full of scrap in this shot and would have sat a bit higher but it gives a good indication.

I wasted too much time faffing with prop shaft bits and wandering around in circles rather than achieving progress. Luckily my hoard of old prop bits came in handy. I used the angles of the various yokes and a centre bearing with a triple labyrinth seal normally used on rock crushers to find the maximum possible up travel and still clear the starter motor then built a new front chassis to accommodate the new full bump height. This is about 7 inches higher than standard. I've got my engine about two inches lower than standard crank height to make everything more awkward. The chevy starter sits quite low above the prop. I'm using a 101 gearbox originally to keep a nice short drive train but it's actually counting against me here. I might put a standard range rover LT 95 in and get a longer front prop and one link happening and reduced angles all round.

The current one link with 101 box will be around 52" long and use an SU ball joint. The extra up travel and low engine is also giving all kinds of packaging problems. I'm not sure how the PTO for the front winch is going to work and there's no room any more for a hydraulic pump setup like Team Idris has as the diff lock actuator is too close to the crank.

My plan at this stage is to build an A frame upper and two lower arms for the rear. I'd welcome any input from anybody who would suggest why a four link might be a better setup? The build would almost identical in terms of cost and time, in fact, the four link would be easier than the A frame possibly. I have a bunch of 1.25" Creeper joints from Off Road Armoury (who were great to deal with and very helpful) with which I could build a four link. I'd use another SU joint I already have for the ball on the A frame which has no restrictions to rotation and +/- 20º for up and down. Intuitively I'd say the A frame and links would be stronger and give me a roll axis in the ballpark of where I'd want it with the front whereas the four link setup in my mind would struggle to give the triangulation I'd want with the link lengths required for decent travel and the separation available within the width of a Land Rover chassis. I can achieve the same anti squat with both setups but feel metalastic bushings in the A frame will add strength and durability not found in the fancy rod end style joints.

Share this post


Link to post
Share on other sites

Following the requests of a few lads on here to see what happened, here's yet another thread resurrection of the vehicle my Mother calls 'Doomsday Dobbin'..

We left the thread a few years ago with sumb axles bolted rigidly to the chassis and I went back to work overseas. It lives outside as part of the ecosystem in my absence being natural habitat for moss and lichen. I'm not blessed with green fingers but over the years seem to have grown some epic gardens of moss in various land rovers.

On one of my leaves home I decided to try and get some rear suspension happening after I got a wee fright when I thought something broke but it was actually me freewheeling down a hill with the front tyres spinning on the rims with no air at all in them. The front tyres are on 9" rims and the backs on 6" rims. I put the tyres on the 9" wheels without tubes or flaps as the sidewall was enough to keep it up with the 6" wheels. I didn't think of this when they randomly ended up on the front. I do my unimog tyres with an engine crane but these were too hard so I had to make a press to fit them but once mounted they were actually really loose. The tyres are just temporary for mockup. I'll find some real ones at some point, they need to be light. Interestingly it was able to drive some really steep and lumpy ground without any suspension at all and bits of wood jammed in the difflocks. Like a big argocat with really bad steering and no brakes at all. The chassis also flexed quite a lot which was surprising given the construction.

 

The plan was to continue with the 'low rider' concept and match the rear axle bump height with the front which is 7" higher than standard. The 7" comes from 5" of portal drop plus the larger axle diameter to leave the wheel centre in the same place. This would allow the axles to articulate without lifting the COG unnecessarily. I chopped the chassis for the fourth time after building it and started to graft on some low rider rails.


The material for this came from a local radar station that blew down in a storm. On my previous trip home I helped the contractor chop it up and remove it from site. Interestingly there was a guy from the civil aviation authority there overseeing progress who told us there were about 160 of these installations around the world and only two have ever blown away, both of them at Wanlockhead. The new one has a continuous rating of 200 knot winds so should last a while. 

 

IMG_7217.thumb.jpg.876bf53ca0a5436d2bb9c1110e716dff.jpg

 

This is the point the build went horribly wrong!!
I had a perfectly functional vehicle that drove into the shed, it needed a bit of welding and some suspension and it could have driven out as an even more functional vehicle.
I started cutting the low rider bits with my brand new tungsten carbide chop saw and huge pile of free radar metal. The saw kept cutting bits the grinder started grinding and the welder started welding bits and before you knew it a chassis rail happened all by itself. Then two rails then my poor landy was in bits all over the place and the cuttoff saw went through the old chassis!

This is also why I was interested in team Idris's current chop as had I just kept welding to the original chassis it would have been out the shed and been a functional toy instead of an almost abandoned project waiting it's turn.

IMG_7220.jpg

IMG_7259.jpg

IMG_6353.jpg

  • Like 1

Share this post


Link to post
Share on other sites
14 minutes ago, Jamie_grieve said:

The material for this came from a local radar station that blew down in a storm. On my previous trip home I helped the contractor chop it up and remove it from site. Interestingly there was a guy from the civil aviation authority there overseeing progress who told us there were about 160 of these installations around the world and only two have ever blown away, both of them at Wanlockhead. The new one has a continuous rating of 200 knot winds so should last a while. 

That was the same storm that blew my workshop away on the other side of the hill, I remember it well :D

  • Like 1

Share this post


Link to post
Share on other sites

The plan was to just stick it back together as it was but with the new improved radar station chassis and some new captive engine mounts made from a bit of radar channel with some 300tdi mounts as they fit perfectly together. It was actually the engine jumping out the mounts after hitting a rock that led to the first time it was laid up and I really wanted to address the issue properly. The mounts were regular V8 bonded mounts and they just tore apart like paper.

I settled on an A frame and lower links for the rear suspension after considering a four link. I decided that by starting with (and then regretting) using Land Rover dimensions for the chassis instead of a complete tube frame I couldn't get the degree of triangulation I wanted for lateral location strength with a four link. Even then, the A frame was going to have to be longer if it was going to be an improved forest rover with better suspension. I decided the A frames had to go through the chassis to get the width I wanted and the length needed for the vertical wheel travel. I built little tunnels through the chassis with cut tube and flat plate and creeper joints. These sit at an angle like the Land Rover ones do but there's enough movement in them to allow it without any binding. The lowers are 51" long and the A frame about 37" I think.

I was going to upgrade the steering box to one from a Renault TRM2000 as I measured the pull on the pitman arm at 4 tons with my scales. I also distracted myself for a little while looking at the TRM portals but put them back after wasting some time with them. I'll build an independent sprung buggy with them one day maybe.

The steering also lead me to another problem, what suspension to use on the front. I decided a one link would be the way as a three link was proving difficult to package and a four link would mean hydro steer. I wasted a huge amount of time trying to get a onelink to fit but it just wasn't happening. I tried mocking various shapes up with concrete rebar which is easy to work with but I was tying myself in knots with it.  I wasn't going to move the engine up out the way and nor was I going to compromise on the articulation or hydraulic pump fitment at the front with various other link geometries so I decided after much deliberation and many mockups to go with a front mounted A frame and lower links as well. I used SU joints for the A frames and have 13" of link separation both front and rear. The Sumb portals are also handy in a way that the inner lower parts of the portal housing are of a weldable material which makes lower link placement really easy. The A frame obviously has the same implications as the four link on the steering. Ultimately the A frame was easier to package round the engine than the upper links of a four link and the high roll centre moves the wheels away under articulation.

I settled on my link geometry the old fashioned way with a scale model on the garage door after wasting far too much time on the Pirate4x4 link calculator. I also played with the notion of a Watts link before settling on the A frames. 

 

It was all going so well then something else happened.....

 

IMG_7332.jpg

IMG_7331.jpg

IMG_7384.jpg

IMG_7421.jpg

IMG_7432.jpg

IMG_7445.jpg

IMG_7564.jpg

IMG_20160915_194649.jpg

IMG_20160915_202248.jpg

IMG_7409.jpg

Share this post


Link to post
Share on other sites
3 hours ago, Soren Frimodt said:

Great to see some updates on this :i-m_so_happy: So is the engine getting center-mounted then?

Thanks, wasn’t thinking there would be much interest.

The engine is in the same place as in the previous incarnation if we used the bulkhead outriggers as a datum. It’s not mid engined but the gearbox does sit about 8” / 200mm further back than standard and by using a 101 gearbox this brings the engine another 4” / 100mm further back again.

Share this post


Link to post
Share on other sites

You can see I almost started to make some progress from the picture with the watts link mocked up on the front. There's an engine, gearbox, bulkhead, all the sorts of things you might find in a vehicle that's going back together. The watts links were for the steering where I was convinced I could get a watts link draglink to work if I put the drag link centre on the arm of another watts link.

I was in the middle of tying myself in knots a bit with the steering when the sad day happened that I had to let go of one of my old trucks, a Berliet GBU 15. The poor lad picking it up hadn't actually been told what a Berliet was other than it was an old classic lorry so probably wasn't expecting a 16 ton lump of green French awkwardness to happen into his life. He had a bunch of scrap on his trailer and had to lose some of it to make room for the Berliet. Amongst the scrap was a Cummins B series from a DAF truck.

I very kindly offered to shift it with the wee forklift and said it might be handy, the owner was a truck dealer and wasn't bothered about it at all. I put it on a pallet and had a scratch at my chin thinking I might just have a gearbox that would fit. I did, I had one from an old Renault lying around so I kinda stuck that on the back, the clutch splines were even the same. I had a wee scratch about in my gearbox graveyard (1st left after the engine graves next to the portal pile) and found a homeless lt230. It made for a very short package if I could make it work. 26 1/2" long from the bellhousing to the rear output o the lt230, the bellhousing was kidding on at being an sae3 and needed chopping back a bit and with a Rakeway short rear output I could get the whole transmission down to about  22" long. With the cummins that gave me an almost Identical length as the GM V8 and LT95 only this was just better in every way. the 6.5:1 first was also giving me an extra crawler gear I didn't have before.

I mocked it up in the chassis and even without the shortening could see some merit in pursuing it. The poor old GM V8 got ripped out and left to rot in the engine grave yard and this is kinda where what should have been a slight deviation from some chassis tweaks turned it into something which meant it wasn't driving out the shed anytime soon

IMG_7781.jpg

IMG_7462.jpg

IMG_7463.jpg

IMG_7701.jpg

IMG_7842.jpg

Share this post


Link to post
Share on other sites

Wow what a turn of events! Even though I'm a petrol guy ti the bone, I can't deny what an epic engine the Cummins 6 is! Cool stuff

Share this post


Link to post
Share on other sites

I bet the cummins made letting go of the Berliet a little less painful :)

Which Renault truck did that gearbox originally come from Jamie ?

cheers

Steve b

Share this post


Link to post
Share on other sites
21 minutes ago, steve b said:

Which Renault truck did that gearbox originally come from Jamie ?

Mine came from a Renault TRM2000 but the bellhousing’s too long. Getting one from a Volvo FL6 or a Dodge 50 might get a proper SAE 3 bell housing. The Renault one has similar dimensions to SAE3 but is 40mm too long and the holes are rotated  15° wrong. I reckon one of these would let you put a Cummins in a mini.

Despite the size I don’t think strength will be an issue, the Volvo 6 cylinders were at least 7.5 ton and I don’t know what a dodge 50 was rated at but way heavier than my forest rover thing could get. I opened one up to have a look and it’s well made with large ball bearings instead of taper rollers. It’s also very light.

Share this post


Link to post
Share on other sites

I scratched around with the cummins and the gearboxes a bit more and couldn't really find a layout that gave me a long enough rear propshaft befitting the travel you'd expect from an updated forest rover. I had 30º of articulation in mind which I decided I wasn't going to compromise on. The wheelbase wasn't exactly cast in stone at this point although the rear suspension mounts were in place all the front links were still mocked up in scaffold pole. I also wasn't going to compromise on C of G and  lift the engine up over the axle which then lead to huge packaging problems. I decided I would put the transfer box where it needed to be to get long enough prop shafts for decent wheel travel then work round about it.

This put the transfer box next to the gearbox. I was going to have to dream up a way of getting drive to the transfer box. I figured a second transfer box would be awesome and give me more gears and pto options to play with. 

Although I hadn't actually come up with a driveline solution I also thought there was enough merit in the Cummins concept to get one that actually worked. I've worked with them for years and really rate them. I  know a local lad that breaks trucks and he just happened to know of a very low milage one that had been in a shed for years in a bin lorry that was vandalised and had problems sorting out the insurance. It was in a Turkish BMC and came with an Eaton 6 speed gearbox, ceramic paddle clutch and sae2 flywheel housing. It also happened to be a 210 hp one with a P pump and exhaust brake on it with the later STORM engine block. I also grabbed a radiator and intercooler from a DAF 55 which was smaller than the BMC ones and a bunch of air tanks, unloader valve and air drier.

I thought a nice engine would be the motivation I needed to get cracking on the project when I was home next time. Although the original engine had been mocked up, the gearbox didn't actually fit properly and to really fine tune the mounts and front suspension I needed the engine I was going to actually use to finalise these things.

 

IMG_20160905_231133.jpg

IMG_20160905_231325.jpg

IMG_20160905_231459.jpg

IMG_20160910_210046.jpg

Share this post


Link to post
Share on other sites

The dual LT230 arrangement caught my eye - some interesting stuff you're doing here!

  • Like 1

Share this post


Link to post
Share on other sites

Doubling up the transfer boxes seemed like a great idea but I couldn't actually run it with the boxes joined together as in the previous pictures unless I welded all the cases and bellhousing together. I did actually consider welding them into one big lump. I want to be able to launch this foresty rovery thingy off things and fully expect to be bouncing it off tree stumps and big stones so having flexible mountings and enough space round everything to reduce shock loads on mounts and casings is essential without causing mechanical stress to driveline components.

I had too many unknowns to work with to determine the transfer case layout so I put the engine where the engine had to go which was more or less dictated by the position of the front A frame mounts,  both how far forward and also the lateral location. The level of the sump relative to the bottom of the chassis and belly plate clearance dictated the height. I messed about with different dumb irons, revisited the one link again and walked about in circles a fair few times before deciding to nail it down. That 6Bt cummins is 512kg so I knew I wanted captive mounts, I also knew I wanted a bit of compliance with some movement downwards, less movement upwards and not too rigid fore and aft so some old spring bushes just weren't going to cut it. I got some tdi mounts which are actually really strong and filled the voids up with some two part 70 shore polyurethane. This gave me nice stiff mounts which didn't really move much with the Cummins sitting on them but is soft enough that when the chassis takes a knock or landing from a jump the mounts have a good lot of movement available and there's plenty of clearance for everything.

in the earlier pictures I had mocked up an LT230 input shaft from a bit of LT77 mainshaft and a spare flange. It went together nicely enough and would probably have even worked for a while if the cases were all welded together in the aforementioned lump but welding them up got binned because it was deemed a silly idea at the time and nothing at all to do with the fact that the Land Rover cases were soooo porous they oozed oil out at the first sign of the welder.  My first thought (after the not welding it, don't be silly thought) was using a rubber doughnut between the first and second transfer boxes but I wasn't lucky enough that everything would line up, fit in the chassis and clear the rear A frame all at the same time. I tried a few different ways of making it happen but ultimately I needed to make the second transfer case remotely mounted and driven. By making the second transfer case remote it also solved the problem of 512kg of Cummins bouncing one way and possibly the transmission another. The remote mount also offers more flexibility from the perspective of where the output from the first transfer case is. The downside was packaging as now all the various bits of gearboxes now needed enough room to thrash around without bouncing off each other or cause any strain on drivetrain components.

I was really tight for space, you can see in the previous posts' picture how close the rear of the first transfer case is to the rear A frame with the front output close coupled to the input of the second. I needed to make the shortest possible remote drive shaft. I used a puma spud shaft and cut splines in it to suit a prop yoke from a classic range rover or disco one V8 auto. I ground the prop yoke a wee bit to clean it up to take a seal for the transfer case so the yoke itself now forms the sealing surface. I loctited the splines when I pressed the yoke on so they didn't leak. I got another V8 prop yoke and put it on the first to give a female spline, cut the sliding bit from a prop which was as long as I could find and yet another V8 yoke for the other end with a regular flange on it. This gave me a proper propshaft with all standard easy to get components for when the Cummins snaps them like twigs. I did destroy four propshafts in my quest to build my shortest ever shaft. By doing it this way it saved me over 60mm compared to the likes of a Rakeway remote input.

IMG_7873.jpg

IMG_20160929_165511.jpg

IMG_7913.jpg

IMG_7914.jpg

IMG_1832.jpg

Share this post


Link to post
Share on other sites

Interesting to see what you've done with the Discovery 200tdi engine mounts. They're the same ones I'm using for the merc and I was wondering about adding a little rubber to them more to stop any sideways movement. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy