Thread: Bonnet Latch Cable Improvement.

Originally Posted by Dougal

Waste of time. The friction is in the cable, not the latch.

Really?,I've never replaced one in 8 LR's I've owned and treated that way. Pat

Originally Posted by PAT303

Really?,I've never replaced one in 8 LR's I've owned and treated that way. Pat

I know of a few people that have broken the pull handles on the defender bonnet release. You can lube the latch but the cable itself gets very sticky and no worky so good.

Originally Posted by PAT303

Really?,I've never replaced one in 8 LR's I've owned and treated that way. Pat

Did you read the first sentence perchance?

Disco and RRC.

Ran a magnet round my first Disco to see what was what...ditto the RRC.

I'm reasonably certain there is no problem with the release mechanism ie no misalignment. As discussed, the extra leverage provided by the shifter does raises the bonnet once the cable is pulled. But when convenient I will play with any adjustments just in case there is misalignment or some other improvement to be had.

Also getting a second RRC next week, and when was inspecting found same issue of seemingly weak lift spring.

I did once in desperation try using high density irrigation dripper line as a sheath but soon gave up and found a mower repair place for cable.

Did you say 3 horsepower?

I bought a book describing how to home build an EDM years ago, not a wire but solid carbon, got many of the parts, including hi volt capacitors. Sounded like building it was a toss up between success and electrocution – eventually I will start...

EDM is neat technology but why build output shaft using EDM rather than conventional hobbing or grinding or whatever? Are you turning to size and then EDMing the splines maybe? You don't run your own shop by chance? I dabble with a mill and lathe as an amateur self taught but not greatly progressed skill wise.

You happy with solid works? Heard of it. Used to dabble with Microstation and TurboCAD for basic drawing but no CNC cross over ability as far as I'm aware as a novice.

If I had the where with all I'd like to build a timing gear system for the Disco1. Throw the current timing clam halves away and reconstruct so that the gears are supported by both sides of the clam – there was a system (name slips my mind – Zuse Zoos Zuss) that got mixed reviews (ie some failures) but it relied on one side of the clam for supporting the gears as far as I could see.

Then there's portal axles...

Dormobiles roofs...

Variable turbos...

I guess I'm in danger of having the thread wander off course.

Originally Posted by workingonit

Ran a magnet round my first Disco to see what was what...ditto the RRC.

I'm reasonably certain there is no problem with the release mechanism ie no misalignment. As discussed, the extra leverage provided by the shifter does raises the bonnet once the cable is pulled. But when convenient I will play with any adjustments just in case there is misalignment or some other improvement to be had.

Also getting a second RRC next week, and when was inspecting found same issue of seemingly weak lift spring.

I did once in desperation try using high density irrigation dripper line as a sheath but soon gave up and found a mower repair place for cable.

Did you say 3 horsepower?

I bought a book describing how to home build an EDM years ago, not a wire but solid carbon, got many of the parts, including hi volt capacitors. Sounded like building it was a toss up between success and electrocution – eventually I will start...

EDM is neat technology but why build output shaft using EDM rather than conventional hobbing or grinding or whatever? Are you turning to size and then EDMing the splines maybe? You don't run your own shop by chance? I dabble with a mill and lathe as an amateur self taught but not greatly progressed skill wise.

You happy with solid works? Heard of it. Used to dabble with Microstation and TurboCAD for basic drawing but no CNC cross over ability as far as I'm aware as a novice.

If I had the where with all I'd like to build a timing gear system for the Disco1. Throw the current timing clam halves away and reconstruct so that the gears are supported by both sides of the clam – there was a system (name slips my mind – Zuse Zoos Zuss) that got mixed reviews (ie some failures) but it relied on one side of the clam for supporting the gears as far as I could see.

Then there's portal axles...

Dormobiles roofs...

Variable turbos...

I guess I'm in danger of having the thread wander off course.

I tried irrigation pipe on a bike in place of cable outer once. Same result.

Yes a 3HP diesel is about the limit of what you can hand-crank. Forget all notions of cranking a man-sized diesel.

This particular shaft was built about 6 years back and fully hardened, this is just modification. EDM should be the easiest and cheapest method to put two holes through it. Softening it, drilling/boring and then hardening is risking more shape change. It already moved enough on original hardening that the end that was tight went loose and the end that was loose went tight.
Originally it was cut external splines and EDM internal splines using a plug they made to fit the gearbox output shaft I supplied.

Arc-air gouging rods aren't too far from EDM.
I have enough gear for prototyping and getting my own stuff done. Any real builds I sub-out. I've got trustworthy machine shops, fabrication and sheetmetal places I deal with.

Solidworks is full of bugs and the company that sells it are *******. But that appears to be true of all CAD these days and it lets me get stuff done that would otherwise be impossible. The inventor users complain about inventor just as much as solidworks users complain about solidworks.

A DIY timing gear set is a serious exercise. But if you could pull it off the market is probably there. Especially since the US guys are buying up all the 300tdi landrovers with rotted out bodies from the UK and shipping them over. The US guys mistrust timing belts almost as much as turbans.

The bonnet safety catch-latch changed locations between my 85 and 93 rangies. The 85 works front-back. The 93 sideways.

1982 RRC seems to be back-front

Do you cryo your work for the austenite to marsenite?
Given your EDMing due to milling difficulties then your work is tempered for hardness over strength? I understand strength over hardness is machinable. But then as you say you may get distortions if you machine.

At the risk of taking this thread in another direction can you recommend a thread that has covered the construction of the adapter shaft in some detail. I'd like to see the differences in approach to work like yours, Sheldons and others. I've yet to tackle this adapter issue. Was thinking of getting an Isuzu drive flange and Ashcroft output spline, press fitting together and welding as a last resort.

Cheers.

Originally Posted by workingonit

1982 RRC seems to be back-front

Do you cryo your work for the austenite to marsenite?
Given your EDMing due to milling difficulties then your work is tempered for hardness over strength? I understand strength over hardness is machinable. But then as you say you may get distortions if you machine.

At the risk of taking this thread in another direction can you recommend a thread that has covered the construction of the adapter shaft in some detail. I'd like to see the differences in approach to work like yours, Sheldons and others. I've yet to tackle this adapter issue. Was thinking of getting an Isuzu drive flange and Ashcroft output spline, press fitting together and welding as a last resort.

Cheers.

I have a thread on my rangie called "the 85 classic" in the Isuzu section. But I'm not sure how much detail I've gone into. The thread was written sometime after, but covers the planned mods I'm doing now.
Ancient Mariner has some beautifcul machine work with his MXA-5R to LT230 shafts in the Isuzu section too. He has taken a different approach again which is well worth considering.

TBH I don't put any faith in "cryotempering", I've yet to see any hard science on how or why it is supposed to work. Conventional heat-treatments are all about controlling the mobility of individual atoms through the material (carbon in steel, copper in aluminium etc). When you cool something you're actually inhibiting the mobility, so how is it supposed to acheive anything?

This shaft was hardened for strength. It should acheive near ~2000MPa yield and I determined that most of that was needed in the worst case traction situation.
I do understand the concerns with EDM regarding strength and fatigue as you end up with an "as-cast" surface finish which isn't good.
But the EDM I have is all internal and highest stress in the shaft is all external and fully machined. So for that I'm happy.

I did however slip and nick the shaft before it was heat-treated so it does have a nice stress-rise right on the neck down to the smallest diameter. If it's going to give me any issues, it'll be there. But so far after about 6 years it looks like the day it was put in.
It's also not wearing the LT230 inner splines, which is good.

The original adapter shaft in my rangie (not my work) was made from pressing and welding a turned down Isuzu output flange to a modified lT77 output shaft. It was hideously ugly and put a weld right where the LT230 input seal goes (wondered for years why it leaked). But it worked.
I modified it a bit to fit the seal where it should go, then happily ditched it when I swapped to a later Isuzu gearbox with a different output spline. At the time I couldn't figure a way to tension the adapter shaft onto the gearbox main shaft. But I since have which is where the current modifications come in. I have some significant gearbox chatter at low rpm which this modification will hopefully reduce or stop.

How do you define worst case traction situation - over the cliff?

auto boxes seem to protect the LT230 splines despite no cross drill for lube.

Will read your suggested posts though I suspect I might have already read some.