[seanzook06]

Needing to build a "cage" for mine in the next week, I have seen builds like hedgehog do a steampipe cage tied into the cab, mine is a soft top however, is there any reason I can't just tie the windscreen back to the targa bar and have it all removable as one peice? Bush only rig so rego isn't a concern? My current design is a steampipe hoop fully welded around the windscreen frame, another hoop fully welded around the targa bar, and two bars connecting where the rails normally are,
along with an additional brace running horizontal between the two rails,
keep in mind this is not a comp cage, it is simply in the interest of not constantly bending windscreen frames and targa bars,
any reason why this wouldn't work?

[Gwagensteve]

A number of cars in the Vic club (and jonno_racing) have something like what you are describing.

[seanzook06]

Cheers,
Was thinking something a lot more tied into the cab than most of those, completely welded into both the window frame and targa bar, following the same curve. Essentially I don't want to make the car any wider than it is now. it's more bracing the cab and making the windscreen frame and bar 1 peice.

[Gwagensteve]

Hmm, I'm not sure I'd recommend that. The targa bar and windscreen frame are weak, so you'd have to also connect the bar work to the tub elsewhere. All up I think it's a bit of a messy solution.
The reason to weld bar work to the pillars/roof on a hardtop is to stop the cab twisting and the glass falling out/doors not fitting after contact with the ground. That's not the same problem as a soft top faces - for soft tops, it's the targa bar being too weak and the windscreen frame copping a hiding that's the issue.

Note that while Phil's exo does attach to the sides of the body, The bar work on other two cars I posted doesn't add any meaningful width. We are very conscious of this being an issue for our terrain.

Here is another solution - GregC's car has a cage that attaches to the cowl and tub but the windscreen frame and targa bar have been notched to clear the bar work. This arrangement adds no bulk at all to the car and the targa bar and windscreen frame are still removable.

[seanzook06]

Looking at that I think what Gregc has looks like it will work best for my application, thanks for the advice

[Gwagensteve]

A couple of points to note about GregC's cage -

It's Gr350 roll cage tube - significantly lighter than steam pipe and the cross bars were rolled to mimic the shape of the top of the screen and targa bar which is part of the reason it's so tight to the car. Greg added a cross bar at the base of the screen to help prevent the cage being punched through the cowl in a hard hit, and the top of the tub has been reinforced to prevent it collapsing.

None of the stock roof hardware will fit so the car is open 100% of the time now. Greg has experimented with different materials to make a roof skin to keep the rain and sun off but hasn't really arrived at the perfect solution.

He has rolled on it and it held up fine. It's clearly not designed for competition but for our terrain it's plenty.

[seanzook06]

Cage so far. I ended up using 2.6mm Nb pipe. Not the most ideal, but it was what I could get my hands on easily.
aiming for a Weight of less than 15kg all up. Sitting round 10 at the moment so should be fine by the time I put in the rails to join front and rear.
Total protrusion from the car is 55mm, at the base of the windscreen. this is limited by the 3mm mount welded to the panel, and the radius of the steam pipe bend where it bolts through to the mount, aside from that it pretty much follows the panel lines everywhere else

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