Diesel Gearbox Protection

[Russel]

Well i achieve it with very large tires and can still do 70 + on road.
All to do with ring gear to 3rd and 4th ratios.
And the fact that you idle over object and i mead idle.
Russel

[jed the spread]

Jed, simple bashplate

Beautifully simple...

A big rock could slide over that nicely, no catching or snagging on grooves etc. It can be fitted with ease (might just keep one of these in the glove box) just before you decide to go off road driving and take it off when your not, just a case of getting into a routine like when I plug my ebber up. A TD has the wind tunnel panel so loads of air is passing underneath (not that I go that fast off road) but in my own mind due to the useful discussions in this thread, I feel the fins on the gearbox are more an external skeleton giving strength to the hollow inside that needs all its internal room for gears. I am kind of thinking like an inside out plane wing but obviously could be miles out

Bottom line for me is, Yep thats what I am after

jed

[HarryMann]

Ribs are indeed a well proven way of getting stiffness for minimal additional material (cost) and mass (weight)

Some commonality with the (rear) base of the skull, and of course the rib cage...





etc. etc.

[silverbullet]

It's been a while, so I've done a bit of thinking and after Pete's observation:

How are those that are going to use a protection plate to drive over the massive bolders going to protect the area in the red circle

I've come up with this as a first attempt:



To be welded onto the front face of the crossmember. This will reinforce both the cantilevered brackets that are so badly bent upwards on Jed's DOKA and the crossmember itself. The two vertical side plates at the front of the engine rails (below red circles) will also be replaced with a pair of ~30mm square box stanchions to stop them buckling.
I have thought that maybe a slightly more elaborate arrangement with rubber elements (rear damper eyes and bushes?) might be a good idea to introduce a little compliance and reduce the shock loading, but that's for MK2.

[HarryMann]

What area is that exactly... the handbrake cable?

[silverbullet]

I took it that Pete was referring to the forward projecting angle brackets that carry the prop bars/front end of the engine bars. Because they are cantilevered, they are the next weak point as they project forward approx 55mm from the front of the body crossmember.
Looking back along the propshaft:

[PC52]

Correct Ian, I'm thinking to go a bit higher and include a bit of floor space aswell

[syncrodoug]

I've carefully positioned* a nice bit of 80x80x4 box and an equally nice piece of 50x 6 bar between mounting points and floor - I'll try to take a picture tomorrow.
Doug
* involved use of a big hammer

[syncroandy]

Interesting stuff. But perhaps the more you strengthen all of that, the more shocks will be transmitted to the rest of the shell, maybe risking the tightness of seams. Maybe having a bit of 'give' in the under-protection is no bad thing ? They can always be beaten or pressed back into some sort of shape. I'd be inlined to maybe a add thinnish ally sheets in a few places and leave it at that.

PS. and some braces for the prop bars.

[syncroandy]

Thinking about it though those brackets are a bit $h1t. As the crossmember is the loadbearing bit a heavy brace welded between that and the bendy brackets should do it ? Love to see Dougs solution though !

PS. I've not bent one yet myself (IIRC) but then I do drive a bit steady compared with some.

PPS. I must buy a MIG welder anyone know of any good deals ?

[silverbullet]

Maybe having a bit of 'give' in the under-protection is no bad thing ?

That's why I'm not quite happy with the solid version, it feels like half a job to me. I think It's time to cut the eyes off some dead rear shocks, the ones on the syncro aren't far off that anyway
Then I'll have to look at the front end and the bashpate I haven't made yet, but I can see it being worthwhile if it helps the old thing last the course, what with this sort of abuse so late in it's life...

[HarryMann]

Interesting stuff. But perhaps the more you strengthen all of that, the more shocks will be transmitted to the rest of the shell, maybe risking the tightness of seams. Maybe having a bit of 'give' in the under-protection is no bad thing ? They can always be beaten or pressed back into some sort of shape. I'd be inlined to maybe a add thinnish ally sheets in a few places and leave it at that.

PS. and some braces for the prop bars.

Pretty much how I'm thinking at the moment... haven't bent anything seriously yet, other than the pan itself and the front bashplate (highly remodelled)

[syncrodoug]

In the agricultural style.......

[silverbullet]

In the agricultural style.......

[HarryMann]

Is that steel and wood Doug, steel to spread the load into wood to spread the load into the floor over a wide area..

Def.not.a.fan.of too stiff a solution, else who knows what will 'give, agree Ian.