Blanking a Rear crossmember/strengthening

[white90]

Courtesy of Neil (V8-Freak) oh - and his bank account

This is how I recently blanked off the back of a standard genuine rear crossmember. While most people wouldn't go quite this far, perhaps some of the thread might give you some ideas. The object is to completely close off the crossmember to prevent water, etc from getting inside it, so all holes have been filled in with weld - leaving just the jacking points and the holes for a NATO hook. There will be a couple of drain plugs on the bottom edge so that they can be removed and waxoyl squirted in and to drain occasionally should some water find it's way in.

The back of the crossmember is pretty flat anyway - just the attachment points for the rails, the tank mounting point, and the exhaust mounting. These are all cut off so that the back is as flat as it can be, then individual plates cut from 2.2mm sheet steel. The crossmember is naturally strengthened by doing this, plus it has in effect three walls to it (the centre one being the previous outer one.

Loads of careful welding, which has to be a continous seam for obvious reasons, then lots of work with the angle grinder/flap wheel to hide my bad welding tart it up.

Chassis mounting tabs - two either side. A straight edge to make the cut mark and then a plasma disc to remove them.

This is the tank mounting bracket - it doesn't need to be this big really as there are just two M8 studs to support the rear of the tank. I'll just fabricate a couple of brackets to do the same thing.

Chassis rail mountings on the opposite side - again cut off flush.

The exhaust mounting bracket - mark it's position and then cut it off.

The cut crossmember. I have to keep the jacking points and they are standing a bit higher than everything else. Once the rear plates are on I'll grind them flush and weld.

The plates all cut and ready to be fitted - including the two 8mm spreader plates for a NATO hook.

The plates laid in place to check, then clamped, a spot weld here and there to keep them in place, then weld each one all the way round.

The exhaust mounting bracket welded back on and the jacking point ground off and then welded.

Some considerable time welding and then tidying up.

All the holes next - there are loads of the damn things. A short burst with the MIG, let it cool, another short burst, and so-on until the hole is filled, then grind flat.

Pictures of lots of holes

Finally the 8mm spreader plate on the outside - welded in place. The rear one will be welded in the remaining recess on the back of the crossmember after crush tubes are fitted, then drilled through from the back.

Hard work, and a lot of very tedious welding

Les.