Thread: Built some "4 way" rock sliders/air tanks/steps/recovery points

Whats the issue with tube? I can get seamless hyd TUBE rated for just as high a pressure as pipe, and in some instances higher.

Generalisation is the issue. Imperial nominal bore (N round hollow steel is NB PIPE, measured internally is not an exact internal size, with wall thickness increasing OD as wall increases.

Metric & Imperial CDS (cold drawn seamless) TUBE is measured externally, with wall thickness reducing internal diameter.

Both are OK for pressure apps but NB Pipe is very heavy due to the wall sizes. I have tested SHS 150 x 50 x 2 for the same application (sliders with tank) for my D2 and a 2m length with just weld capped ends will not deform until 408psi, once I welded some inserts through it for the bolts going into the sills I couldn't get it to deform but it did start to split a weld at just over 600psi.

Should survive a ARB compressor or I can pump up before going away and have a large reserve to start with.

Originally Posted by clubagreenie

Whats the issue with tube? I can get seamless hyd TUBE rated for just as high a pressure as pipe,

Tube is structural, pipe is for fluids.

AFAIK there is no such thing as "hydraulic tube".

However in general I agree with your statements. As long as you know what you are doing there is no reason you can't build vessels from tube for low pressure applications such as tyre inflation.

Anything measured OD is tube (and can be Met or imp), Pipe is measured NB (ID) and is only Imp (though there are metric equvalence tables).

Used to sell it all.


This was my biggest bugbear, someone comes in (and usually the Hyd fitters were the worst) "want some 1" OD pipe"
"so you want either 1/2" NB sched 160 or 3/4"sched 80?" "NO! 1" OD pipe"

At that point I'd give them the book, tell them to find it since they knew better and go make coffee.

Originally Posted by clubagreenie

Anything measured OD is tube (and can be Met or imp), Pipe is measured NB (ID) and is only Imp (though there are metric equvalence tables).

I am aware of that. However as mentioned I have never heard of the "seamless hydraulic TUBE" you mentioned???

You can't get (well in 12 years I never got asked for, offered, sold or whatever) anything but CDS tube (not ERW) or NB pipe. In steel Van Lewyn is the main supplier in Aust but I used to buy around 8-10,000 tonnes / month (flown in mostly). In stainless Sandvik makes it all but only brings in imperial, Stauff (ex employer) "brings in" the metric (piggybcked on the sandvik shipments)

'I could ask the guy who is currently repairing my doors though what he would charge to make a copy. He only charges $30/hr, so it might work out cheap enough.'

'Do you have sill tanks though? I had to modify one of mine when I fitted a sill tank.'

$30/hr!, he must be stuck in the 70's!, are you getting the frames hot dipped? Maybe ask him how many hours he reckons. My steps are steel JRA's, they tend to flex too much for my liking with a high lift under them. I do have one sill tank for the RHS, but still debating whether to fit it, and what to fill it with.

Originally Posted by 1103.9TDI

are you getting the frames hot dipped?

Not at this stage (can't have the landie off the road for that long atm). But I would like to hot dip the frames and the B/C pillar one day...

Would anyone care to give a rough estimate of the cutout in the sliders to fit around the firewall?

Anyone got any good photo's of the finished cutout and how the got a good weld/seal in the cutout?