THE ROLL CAGE
The original roll cage Mark supplied me with wasn't what I'd ordered - it was designed so that the forwards facing stays attached to the chassis top-tube, like the standard roll bar does, and not the side protection structures. So, that one went back to Fishers, and I got a new one. Unfortunately, it seems that they can't make up a new cage with the side protection structures integrated into the cage without having the chassis as well. It seems that there's no jig and it's all a bit ad hoc... Hhhhmmm...
Ah well, nothing for it but to tack weld the side impact beams in place myself and get them properly welded up and get the whole thing powdercoated by Mark. At least this gave me the opportunity to make a few more mods to the cage before getting it powder-coated.
Doing the side arms was just a question of deciding where they should be and carefully cutting the fish-mouth at one end so it butted up against the rollcage main hoop nicely.
The plate at the end (which mounts to the two beams I added to the side impact structure on the chassis) is made of 2mm steel, the same as the other plates on the rollcage.
Another change I made was to the head-restraint bracket. On the original cage this was a 3mm plate welded to the diagonal - you can see the shiny bit of metal where I've removed it with an angle grinder. But with my new custom seat putting me so low and so far back in the cockpit, this wasn't going to work - it was too high and too far forwards. So I chopped it off.
In its place is a vertical bar of 20mm x 40mm box section welded to the rear of the diagonal and harness bars. It's drilled at the back with 4 32mm holes. The idea is to bolt to this a 3mm ali sheet with padding on it which will fill in the gap between the tubes, and the roll cage tubes will be covered in FIA spec padding. This should give my head about the best chance of getting out of any crash in one piece which it possibly could have...
There's a few other mods I've made to the rollcage, such as a welded-on LED high level light mount at the rear, and a few I'm going to make, like a little place on the main hoop for a GPS remote antenna to fit for touring. Pics to follow.