Shovelhands in the workshop, I did it my way........

[Kiwi Pete]

Your sort of on the right lines here Pete .....

Although it's not quite that simple, as usual....

Having panhard on the rear axle, I've got it, and it's the best way for what I've got, Watts linkage would work, but again, there's a fairly important feature on the axle that would need a fairly substantial mounting made, to get round it. Also it's just more moving parts. Panhard will do fine

The drive axle, cannot have either panhard or watts, there just isn't space, so that kinda scuppers the simple A frame idea, there's also a transmission sitting just where you'd want to anchor the A frame!
So, a pair of trailing arms, much like your pic, with a stabilising A frame at the top, giving three point mounting, which should keep the axle in check in all directions, and negate the need for a panhard or watts link.
Oh, and just to complicate things, the lower arms will have to be load bearing, and have air bags on them, as there isn't any room to fit them directly above the axle, as I'm doing on the rear......
Just ideas at the mo, the mad fecker in the design dept may change his mind yet

Oh, and well done, you've successfully drawn me into to a conversation about this, when I said I'd elaborate later....my fault really, for mentioning it at all.....good to get your thinking cap on though

That was a short sleep, a sure sign of a genius!!
I get exactly what you mean, as I scrolled through the entire thread zooming on pictures (and then lost my phone on the farm for 3 hours because it wasn't zipped in my pocket where I hurdled the fence
Not much room in there at all, so you have already come to the same conclusion about mounting it on trailing links with the bags on top!!
Unfortunately the pressure on those bags would be greater than the lazy axle, due to leverage, so there goes the 'hydrolastic" idea.. as you'd end up with more weight on the new axle than the driven one? Unless the bags were behind the axle, if there was space.
Plenty of time for all that, I'll keep thinking about it. Bloody good work I love ambitious projects especially when they're carried out by a master.

 

[Shovelhands]

Re. Suspension on the rear axle, I wonder if you might run into stability issues?

On most four wheeled chassis the front axle props each front corner up whilst the rear axle is bobbling up and down. Being a three wheeler there is nothing to prop each front corner up.

I can see your idea working if only one wheel rear wheel drops in a small hole or hits a small bump, but if that hole is big enough for both rear wheels on one side to drop into, then she might lie down.

Just musing.

Pete, you know these machines better than most, and appreciate them. And as you know, the beauty of the design is the three wheels, but can also be a hindrance in the stability stakes, as you say, there's nothing at the front to keep it upright!

I'm just musing with it myself, I can see some serious benifits of give the drive axle a bit if travel, mostly downwards, and I'd only give it minimal gap above it, with a big rubber pad, so it can rest back onto its original mounts if need be. But there are downsides, one is being able to control the chassis roll, this may be an issue!

If you look at your Multidrive, and I'm only trying to remember it myself from my brief look at it. You have an A frame arrangement on the front axle iirc, giving good axle articulation. On the rear, the suspension is more of an H frame, or two big arms extending forward, these are fixed together, so there is minimal twisting of the rear axle, only slight movement in the mountings, which iirc are big rubber bushes? This idea would give mae a bit of movement, and retain the stability to a large degree.

It really is, a work in progress at the moment!

And I've got to get to work now! .....I'm late!

 

[Cab-over Pete]

One thing I did wonder......

Whilst you're putting in all this fantastic work, what about some sort of "stability control" to prop up one side on a side-hill?

Maybe something to isolate the suspension on one side or the other? A short, stumpy hydraulic ram mounted vertically above the axle? Charging the ram would push the axle down and stop any axle movement thereby making it very stable on a side hill. Just something for momentary use. Just for those "foookkkk me!!!! That was close!!!! I thought she was gonna go over!!" moments we all have with three wheelers!!

 

[phillipe]

Thanks Pete

Adding suspension to the big axle, is only an idea at the mo, it's going through the design department as we speak, I will wait until I actually get to that stage, if I get there, to explain my idea, it will be easier once I'm doing it. But what I will say now is, my best way is an A frame, but it's not really possible, for a few reasons......so, it will be done another way, if I choose to do it at all, we will see

Is your "design department " the same one I use? I hope walk the dogs to think and the " design department " does it's job also before you start can you see it in you head finnished ,I do that with kitchens bathrooms etc ?the clients sometimes can't and I find it kinda easy to picture it finnished before starting ,it helps me not miss anything

 

[Cab-over Pete]

My trouble is, I get too many ideas and can't settle on one. It's a bit like my spreader thread. I can see merits in all the machines, plus the problems and I then can't decide which is best because they will all be a compromise.

I have been planning on narrowing down a Big A for three years but just can't decide on the best way because narrowing it means it's less stable which necessitates some kind of stabiliser idea to avoid the aforementioned "fooookkkk me!!!!" Moments. Shovelhands and I have spoken about it several times and we still haven't got far!!

Anyway, back to isolating one side of the suspension..... obvious answer is use the air bags. Vent one side and pump the other side with more pressure?

 

[phillipe]

My trouble is, I get too many ideas and can't settle on one. It's a bit like my spreader thread. I can see merits in all the machines, plus the problems and I then can't decide which is best because they will all be a compromise.

I have been planning on narrowing down a Big A for three years but just can't decide on the best way because narrowing it means it's less stable which necessitates some kind of stabiliser idea to avoid the aforementioned "fooookkkk me!!!!" Moments. Shovelhands and I have spoken about it several times and we still haven't got far!!

Anyway, back to isolating one side of the suspension..... obvious answer is use the air bags. Vent one side and pump the other side with more pressure?

But having a holy feck moment now and again is good to check the heartbeat and sphincter strengthometer ,

 

[Shovelhands]

But having a holy feck moment now and again is good to check the heartbeat and sphincter strengthometer ,

It's sometimes very awkward to remove the seat foam though!.......

 

[Cab-over Pete]

Have you ever got to the " pushing your arms out to the cab frame to brace yourself for imminent impact" stage?

The foam problem seems a distant memory when you've got to that stage!!

 

[phillipe]

Have you ever got to the " pushing your arms out to the cab frame to brace yourself for imminent impact" stage?

The foam problem seems a distant memory when you've got to that stage!!

Oh yes , the this is gonna hurt moment

 

[Shovelhands]

Got the other side fettled and fitted earlier today.

made and fitted this, and one for the other side.....

and been stitching it up all afternoon

May have another go tomorrow, if it's cooled down, she's a bit warm at the mo, and I don't want to twist it, I've kept her pretty straight up to now

 

[REStracTORATION]

Got the other side fettled and fitted earlier today.View attachment 540038made and fitted this, and one for the other side..... View attachment 540040and been stitching it up all afternoon View attachment 540042 May have another go tomorrow, if it's cooled down, she's a bit warm at the mo, and I don't want to twist it, I've kept her pretty straight up to now

I will post this down mate
You have a leotard you said didnt you

 

[Shovelhands]

View attachment 540052
I will post this down mate
You have a leotard you said didnt you

You best hang on to it mate, haven't you got a DB to do soon...

 

[REStracTORATION]

You best hang on to it mate, haven't you got a DB to do soon...

Its ok ive got @Thick Farmer on the payroll for david browns he has a saying....

 

[phillipe]

Got the other side fettled and fitted earlier today.View attachment 540038made and fitted this, and one for the other side..... View attachment 540040and been stitching it up all afternoon View attachment 540042 May have another go tomorrow, if it's cooled down, she's a bit warm at the mo, and I don't want to twist it, I've kept her pretty straight up to now

have you had a bit of a tidy up ?

 

[Shovelhands]

have you had a bit of a tidy up ?

Where exactly ....

I sweep up occasionally, so it's nicer for crawling about underneath, but not sure I've done any tidying?

 

[phillipe]

Where exactly ....

I sweep up occasionally, so it's nicer for crawling about underneath, but not sure I've done any tidying?

just thoght we could see more floor than usual,and some wall

 

[Shovelhands]

just thoght we could see more floor than usual,and some wall

Not sure about that! There's plenty on the floor still! , but less bits of metal

Looking at the pics , I need another sweep up...

 

[Half Pipe]

That was a short sleep, a sure sign of a genius!!
I get exactly what you mean, as I scrolled through the entire thread zooming on pictures (and then lost my phone on the farm for 3 hours because it wasn't zipped in my pocket where I hurdled the fence
Not much room in there at all, so you have already come to the same conclusion about mounting it on trailing links with the bags on top!!
Unfortunately the pressure on those bags would be greater than the lazy axle, due to leverage, so there goes the 'hydrolastic" idea.. as you'd end up with more weight on the new axle than the driven one? Unless the bags were behind the axle, if there was space.
Plenty of time for all that, I'll keep thinking about it. Bloody good work I love ambitious projects especially when they're carried out by a master.

would using a different sized air bag on the drive axle balance pressures?

 

[Kiwi Pete]

would using a different sized air bag on the drive axle balance pressures?

Hadn't thought that far into it but yes, it sure would!

 

[Thick Farmer]

Its ok ive got @Thick Farmer on the payroll for david browns he has a saying....

Best thing to do with a DB! I still have nightmares about the time I wasted a good flask of tea to stop a 1694 going up in flames!