Roll cage and roof access (Page 1 of 2)

We used a hole saw to drill into the floor where on the top side of the rail so we could drop the cage into it, and weld all the tops and such, then picked up the whole cage and put 1/2" plates under them, with a weld all the way around the plate and tube.  The fronts were a bit easier, since we had to build a pad to attach it to anyway, so no hole needed.

AH, we read the rules as that you must have a 360* weld, not nessisarly around  a flat plane.  So we welded flat around the areas where we were able, and then up the rocker and around, so that the tube is completely welded around. Make sense?

We are on cage #3 where we drop the legs through the floor for finish welding of all the joints up high..

Mine?

not to mention the big side impact (aka "T-bone Lou") it took in its first race.

Done this many times with Street Stocks....since it's a unibody car close all doors and temporarily weld them in place to give body rigidity and support the chassis from as many axle strands as you can....weld/screw little alignment tabs at the pillars where you cut....often the roof "springs" and you can't get a good alignment again.....Unless it's perfect, mount the windshield with a soft compound and use tabs a la NASCAR...modern urethanes set up hard, and residual stresses can crack the windshield. It's easier with a frame car; I used to bolt on alignment tabs at the pillars and saw away. Check over all cage height! 1/4 inch too tall and you won't get the roof on without a sledgehammer. Best way to weld and mount a cage IMO...

The cage is only a problem if it's a little too tall. You want it as high as possible, but you really only have the bracing to cut away to gain height. If you have to cut the roof to fit the cage, you may be better off raising the hoop until it well clears the sheet metal. Several teams have done this. Most important is adequate head to hoop clearance. Everybody says 3 inches, but I've flipped with more than that and had my head hit the bar, with my belts so tight I couldn't breathe! The more the better....If you have a clearance problem, yes you can angle the roof as you suggested, keeping the windshield frame as straight as possible...I knew a racer who had a distorted rewelded windshield frame in a Rabbit, and the water leakage would take strange paths into the dash and cowl, shorting out electrics. How much the roof "springs" depends on lots of factors, including prior body repairs. Some don't spring at all, but if they do it's a PITA to line everything up for welding. To be safe, I used to use small bits of scrap angle iron, Vise-Gripped together, then I'd weld them at each pillar. Then I'd Sawzall from the back, then remove the Grips. To reweld, lining up the tabs and clamping was easy. Remember this is Lemons....a little heating and beating adds patina....and a pretty car looks cheaty!  Post pics!

We cut the roof off and left it off.  Used the roof sheet metal to fix rusted through floor.  It made the whole process easier.  We had plans to put a stop sign in on hinges for a roof but ended up using it as a fire wall in the first race.  I honestly only thought I would be using the car once for Lemons and then would use it as a Prerunner for my off-road car so the roof was expendable.  Our cage is really an off road chasis and honestly I think it is something like a 14 point cage.   So my vote is to lose the roof altogether cause you don't need it per the rules and build more of a chasis in stead of a roll bar set up.  You'll be happier in the end if you crash or roll.

Ya still not used to staying so clean.... Lot less dust and mud.  I really think it depends on what your racing and how you set up the cage/chasis.  If you can get away with cutting the roof off it makes the whole thing easier.

We built boxes out of 1/8" steel at all attachment points except for the down bars at the back. Was really easy to get the trim right on the front and main hoop AND we had a ton of metal on metal welds for strength (we welded large flat piecs to the thing unibody to minimize the chance of seperation). Then we tacked everything in place and can opened the roof at the right spots to get the 360 welds. Make sure when you're doing your measurements that you don't have to cut through the support truss thats by the windshield (where you have to cut access panels in the roof). We tacked the flaps back down then covered them with gaffer's tape.

This was really simple. We debated dropping the cage through the floor to weld but realized that we'd probably spend a lot of time trying to cut the downbars to fit right and also fit the cage into the roof "hollows" if that makes sense.

Remember: it's a race car thats for safety, not for looks.

don't forget to replace the escutcheon disc after rebushing the grunnion banjos...if you don't, inadequate silencer/damper clearance might create a noise in the boot...