Project 80: Codename Grey Ghost

[Chris]

Frank, sorry but I am not. That almost exactly what I said above. 0, 90, 180, 270 and 360. I maybe should have said 'aligned' rather than phased - I stand corrected, but if you read all of my dribblings then you can see that I acknowledge that. I tried it all at 0 = phased, and I have tried it at 90, aligned but not necessarily as you would say, phased. I posed the question as to how the alignment of the central cross makes any difference as long as it's aligned, but when I tried it and drove it, it was definitely different. But the solution taken from the green one has been to go with the bottom diagram and have the prop close to (but not exactly) one 1/8 out. Why is that? It makes no sense to me at all.

Not that it actually matters, but I am trying to understand why turning 90 degrees has an effect. It must have something to to with the male / female configuration and speeding up / slowing down I guess. But no Frank, I DO understand what phased means. I have been reading about it for damn days. I actually didn't express it very well. Phased is across the bearing caps with the correct yokes at TDC. Still doesn't alter the fact that every text book says all props must be like this and yet everything we know says that there are cases where that rule simply doesn't hold true.

I have found a place in Nottingham this morning that makes custom props. I have mailed them asking about a double cardan joint front prop. I'm still not happy and just haven't the determination to keep taking props off.

Going to do something different today.

 

[frank rabbets]

Other things being equal with a prop shaft in phase running at an angle prop flanges will spin through 1 turn at a constant velocity. The tube itself will be spinning fast/slow though. If you turn one flange 90 degrees i.e. 100 per cent out of phase the flanges themselves will spin through 1 turn at a non constant velocity. The tube itself will be also non constant velocity and different again.

Phasing does not matter if the drive line is on the same axis and the flanges are at right angles to them but the moment you start working the prop shaft at an angle phasing becomes critical. So does the weight of the tube because even with constant velocity of the flanges the tube is spinning back and forth. But you may be unaware at shallow angles. With a steep angle which you have this in itself may cause vibration because the back and forth is increased which cannot be overcome because the prop shaft was not designed for this angle. To overcome this design shortcoming CVJ's were invented.

Now there is another problem=balancing. The prop shaft is usually balanced within the design angle of the standard suspension setup. Beyond this the balancer won't know what to do. You are effectively building a new car Chris but don't have a PhD in automotive engineering which is really what you need. I have got no qualifications at all where engineering is concerned and that's why I keep my LC standard and don't have any problems.

But well done for persevering and glad you believed me when I told you it was not the transfer box. I think you've done well to get it running anywhere near smooth so I would call it a day and just enjoy the drive. The more you drive the more you will not notice what little problems you still have.

There's a good link here. I'm no author but this man certainly is and you'll probably understand him easier than you'll understand me.

http://www.austin7.org/Technical Articles/Propshaft Howl/

 

[Chris]

I may well have a PhD in Automotive engineering but just decided to keep it quiet! Ok, no I haven't. I also have an 80 which hasn't been messed with Frank and it drives beautifully. But if man hadn't developed a sense of adventure we'd still all be sitting in caves drawing on the walls wouldn't we. So I will crack this and all will be calm again. Until I decide to change something else.

Well had a prop free day today. Lovely. Been messing with roof tent, ladders and such and started making a rear ladder.

I'd love it to have been round tube and all wiggly and made from ally but you can't have everything. It looks horrid but I brushed it down later and sprayed it and it looks much better. I shall have it blasted and powder coated naturally once finished. I need to attach it to the top of the tailgate and the lower edge too. But the idea at the moment is to have maybe a sliding section at the bottom that locks so that I can drop the foot onto the bumper to take the weight when I climb it. If it touches all the time it will rub when the body and chassis flex.

The JB tent has a nice big rear door so getting in and out that way as well as getting things off the roof storage location will be much easier. Sorry folks the pictures came out mahoosive!

 

[clivehorridge]

You're right Chris, it does look horrid I would have thought a man of your ingenuity and ability would have made a slide out, under-rack, self supporting, self cranking, auto-lock device, thingy, but no.... it's a ladder, plain and simple and I'm sure very effective

What will you mount it to, the rack or the tailgate?

 

[stumog]

Nice ladder but i not really sure its the best idea you have come up with. Remember when you fell out of a normal tent ladder and that was not even with the hilft in the way.

I thought you were in risk management!!!

 

[clivehorridge]

Nice ladder but i not really sure its the best idea you have come up with. Remember when you fell out of a normal tent ladder and that was not even with the hilft in the way.

I thought you were in risk management!!!

Ah, but you haven't seen the safety net device he's making Stu, it's like a batwing awning, but sits under the sliders. When the sudden loss of weight on the rack registers, it goes off like an airbag, and in 2 milliseconds, there's a safety net all round the truck!

Naughty boy for teasing...

 

[frank rabbets]

He was in a cave last time I saw him. Just come down from the trees thumping metal he discovered with a hammer.

 

[stumog]

[

Very good clive.

I am sure Chris will love the humour

QUOTE=clivehorridge;421307]Ah, but you haven't seen the safety net device he's making Stu, it's like a batwing awning, but sits under the sliders. When the sudden loss of weight on the rack registers, it goes off like an airbag, and in 2 milliseconds, there's a safety net all round the truck!

Naughty boy for teasing...[/QUOTE]

 

[clivehorridge]

Gotta get my own back for Chris calling my truck a cheap and nasty foreign 80.... All good give and take Stu, and I'm sure he'll appreciate some humour after onning and offing propshafts all day Saturday

 

[Chas]

Your ladder is not too dissimilar from mine Chris, mine is only fixed to the upper tailgate and takes my weight very well. I think you are right to support it on the bumper though, I mean after all you are slightly, cough, larger than me.
One thing worth considering, which I'm fairly sure you have, is weight of the ladder, mine is fairly well lifted by the tailgate struts, a little heavier might be a problem.

 

[Chris]

Lads so sorry, had a total computer failure and all your responses have been automatically deleted. I am sure there were many words of wisdom in them but alas, they have all be lost. Oh well. It's such a crying shame. F*** the lot of you

Yes Chas, I am slightly heavier boned than you so resting on the bumper may indeed be a wise move.

 

[clivehorridge]

 

[Chris]

Thank f*** for that

All reset to where I was and the truck drives like a dream. Can't say more than that. OK it needs a tracking check as the toe in etc will be affected by changing the axle rotation but other than that it's all good. Many thanks to Frank for the theories and phone support. OK I just don't see how it CAN be right, but it drives fine so bugger it. Sod the laws of geometry. I'm not listening. La la la.

Not getting anywhere else with the build today, thwarted at every step. Who cares.

 

[Gary820]

Sounds like a result

 

[Chris]

Yes, driven well all day. Even given it a wash and a clean out inside. Both tanks full and water too. Not dropped at all.

Looking quite nice



Just need a new CB mount to go on the tube. Can't really obscure the index plate like that

 

[adrianr]

Looking very nice.

 

[Chris]

Cheers Buddy.

Put new bonnet struts on too. Followed you lot and got them from ebay for £20. Man they're good. I think I might do the rear ones as well. I have been messing with the new rear ladder but the door won't stay up.

But I'd like the ladder on there. I have come up with some flexible mounts so that it doesn't drag on the rear bumper when closed but drops slightly when I climb on it.

 

[Gary Stockton]

The rear struts will defo help. Looks good, CJ

 

[frank rabbets]

Glad your nightmare is over. Can I have my T shirt back?

 

[frank rabbets]

PS Still going to accurately measure my front prop phase. I'll let you know out of interest.