Cab to Body fixing?

[graysworld]

What are peoples opinion or experience with joining a body to a chassis cab. I have an Iveco daily 4x4 and although I know that unimogs flex do these do the same. can they be joined? Do I have to use a flexy join? If I cut out the whole back of the cab will it be strong enough?

Graeme

[marky116]

Hi Grahame

I looked at so many options including a unimog spider (sub frame) which is basically a big x with all ball joints on a 3 point system. Decided it was all to heavy and all to high. Down loaded iveco mounting/coach building manual from internet and decided to stick with standard rubber mounts due to cost and simplicty (Still not cheap though) but small enough to carry spares if one goes bang. Have not had a chance to mount it yet but will be in the next month if all goes well. Will tell you how goes after test drive. Get in touch if you want any more info, HOWS THE BUILD GOING?

Mark

[graysworld]

Has no one else got experience of joining a cab to a body on an Iveco or any other vehicle? do I go for the flexible or the rigid? someone must have some thoughts surely.

Graeme

[RogerM]

The critical factor is chassis deflection, put one rear wheel up on a jack and see how much twist the chassis takes. Ideally the chassis should be loaded up with a weight that comes close to the body when fully loaded.

You can get a rough idea of how much flex you'd need between body and cab by putting a wooden frame of the chassis and watching it move as you jack up the back wheel.

You can repeat for all wheels and see what results you get.

Generally the chassis under the cab is more rigid, the engine and gearbox mounts see to that. So the compromise is to have the body move in relation to the larger chassis movement at the rear whilst staying close to the cab flexible connection at the front. Is your cab suspended?

Using differently sized air bags to support the body works ok, I've seen that on sleeper pods on road trains. Use small movement bags close to the cab, big movement bags at the rear, but able to lock them down for highway use. Tuning and selecting would be the hardest part, how much pressure, how much movement, etc etc. You also need shock absorbers to stop the body moving to rapidly.

The other issue is how much flex can the body take - 5cm of movement onto a welded steel joint will cause failure eventually, a lot of refrigerated truck bodies still use rivets to secure corner posts - but truck bodies have an economic lifespan far less than most peoples expedition vehicles lifespan.

Sealing between cab and body is a real pain for tilt cabs, if you need to tilt the cab for routine checks you'll soon get pissed off with having to undo 40 press studs around the seal - or whatever seal you decide to use. If its not tight it will leak, tight and flexible are hard. Water may not get in but dust by the bucket load will.

BTW wood is a forgotten treasure for body builders, wood flexes, its easy to work and long before low weight composite bodies came along it was the only way a van body got built.

[Josh R]

I have seen some profesional Iveco conversions with the whole the the cab rear removed and phyically joined to the camper section, there was one at Mogstock this weekend. Contect Jim and he might pass on contact details.

jim@foodfight.org.uk

However, most the the professional german converters just cut a hole the size of a crawl through (1m x 1m) and use a rubber/plastic fabric to join the two. Its not difficult as long as you reinforce the wholes you cut in the cab.

There is a germany Iveco website that has the detail of a similar conversion but you'll have to get a google tranlation if you are going to make sense of the text!

Josh

[RogerM]

Originally Posted by Josh R

I have seen some profesional Iveco conversions with the whole the the cab rear removed and phyically joined to the camper section, there was one at Mogstock this weekend. Contect Jim and he might pass on contact details.

Did you see how they tilt the cab?

[Josh R]

The first and second model Iveco Dailys don't have a tilt cab and therefore this is not a problem. You can only remove the rear of the cab and connect it directly to the rear body if there is no chassis flex to put pressure on the join.

A flexible tunnel as previously described is used where there is cab/body flex. It is also used when the cab is tilted for maintanence, it is just a case of detaching the flexable tunnel from either the cab or the rear body. The key thing to remember with this set up is not to place the rear body too close to the cab, as it will prevent the cab from tilting. Truck to avoid are those with high cab release points or spare wheels mounted behind the cad as these will mean you crawl trough distance will be longer and therefore may need a removable floor section to enable you to put weight on it as you crawl trough.......

I don't think you'll have too much problem fitting a crawl trough to an Iveco Daily.

[graysworld]

Thanks for the advice, after checking it out I am going for a flexible join. I have cut the back of the cab away today and it remains stiff. so I will make as large a flexi join as possible with the possible fitting of swivel seats later.

Graeme

[Josh R]

Have a think about security as well, cabs are generally quite vunerable and easy to break into, depending on where you are going I would consider some form of door, mesh, grill or roller shutter to keep the rear body secure.