BC/BJ Legacy Roll Cage Build!

[SLODRIVE]

For some reason, I recently decided it would be fun to build roll cages for race cars and Jeeps. I have several vehicles lined up, but the first one is one of the SLODRIVE cars...Rob's 1993 Legacy L AWD. Although this cage will be fully NASA/SCCA legal, the car is going back on the streets for a while at least, to serve as a rolling advertisement for the business. Follow along and enjoy.

Here's the victim...256,000 miles and a daily driver. Hee hee




First step...ditch the interior to get to some nice bare metal.




After stripping the paint, 2 holes were drilled in the floor where the main hoop will sit. You'll see why in a bit.


(Me) welding some 1/8" plates in the same area. The interior sure is roomy without seats!


Bending up the main hoop with my badass new bender. There's only one spot in my garage with enough height to do this, I might have to find a bigger garage soon.


Here's the plates that I welded into the corners. The plate on the bottom is just tacked in, as is the main hoop.


Here it is standing tall!



Cutting out plates and welding them in the front corners:




Next come the two front hoops. They're also tacked in at the bottom for now.

It's starting to look like a cage...Oh yeah, I yanked the dash out too before the front hoops went in.


Notching tubing with a hole saw. Messy but it works.


Upper windshield brace...


Now you can see why I put the holes in the floor. After removing the tack welds from the plates and the main hoop, the plates can be slid out and the cage can be dropped through the floor to gain 360 degree access to all the welds on top. I also added a diagonal bar across the top at this time.


Then the plates are slid back in, and all 4 tubes are fully welded to them, as well as welding the rear plates in.


Now we're getting somewhere. More to come soon!

[NICO]

wow very nice !! your doing a good job.

[Legacy777]

Yes, very nice!

What plasma cutter do you have? How do you like it and how much it run you?

[SLODRIVE]

Thanks guys, more coming later today.

My plasma cutter is an "Everlast" brand, it's basically a Chinese/Ebay special. I found that the $700 plasma cutters (which is what this one cost) work every bit as well as the Miller/Hobart/etc. units...they're almost all the same electronics. Besides some very minor issues (air hoses coming loose inside the case, fixed now), it works great. It'll sever steel about an inch thick!

[SLODRIVE]

More cage!

Diagonal bar in main hoop


Although not required, I put a dash bar in.


I was worried about the vents at first, but it only took a bit of trimming to clear the bar. I'll do the same thing to the dashboard in the same area and all should be good (I hope).


Here's a part I'm pretty happy with, that'll just get hidden. I managed to salvage the column support bracket and the ECU mounting bracket from the OEM "crash bar" that was there before.


Looking more like a cage now! Stay tuned.

[beatersubi]

That is awesome! Its basically all the things I've been wanting to do but lack funds to. My rally car has been sitting at your first stage for almost a year now.
Have you seen/tried the sawzall method of notching pipe? What're you gonna do for gussets?

For all the other aspiring fabricators out there: Home Depot ( ) has a Lincoln 140 amp wire feed w/ regulator for $525. 110v, but still...

[SLODRIVE]

That is awesome! Its basically all the things I've been wanting to do but lack funds to. My rally car has been sitting at your first stage for almost a year now.
Have you seen/tried the sawzall method of notching pipe? What're you gonna do for gussets?

For all the other aspiring fabricators out there: Home Depot ( ) has a Lincoln 140 amp wire feed w/ regulator for $525. 110v, but still...

Thankyouthankyou!

Notching tubing with a saw is bullshit, you can't get a proper fit. Hole-saw notcher or plasma cutter for me!

I'll probably order gussets from Speedway Motors, they're the best for that stuff unless I cut out my own.

[evolutionmovement]

Beware of Home Depot tools. Dewalt and probably other tools there are cheaper because they are lower quality than the standard product. I know with the Dewalt stuff, the HD versions actually have their own serial numbers and you can't get parts for them. I've heard the same about some other brands, too, but I know of the Dewalt example personally.

[SLODRIVE]

To be honest, I wouldn't build a cage with a 110v welder anyway. I tried welding a stock-car cage together years ago with a Lincoln/Blue-Point 110v MIG, and the weld penetration was, well, not good enough to be certain it would save your life someday. I borrowed a big Hobart to re-do/finish that one, and then got a 240v Millermatic DVI so I wouldn't have to worry about such things. It was about $1000 6 years ago, but I sure as hell don't regret it.

Here's all I have left for tonight. The rear support bars are now done, also welded to 1/8" plates on the strut towers.

[93forestpearl]

I've been thinking about doing the back-half version the that cage, with lower bars than run up to the front. I would merely be for crash safety in these old cars that are wet noodle compared to newer cars. That and I'll be scratching the at the line of high 10's.

I want the car to be driven safely without a helmet though, so no bars by the driver's head. It's a project for this winter though.


I would, however, build in a harness bar. Also, the main hoop would have an X verses a single triangular brace.

[evolutionmovement]

In my books, Duchess has a reinforced chassis hidden from view. One of them is a steel bar that fits into a notch on the inside of the B-pillars. Not as strong as a real cage, I'm sure, but I was amused to see the newer versions of our chassis used the same idea.

The problem is damned doors—it's tough to make a chassis strong and light while working around those giant cutouts for the doors. Making up for that requires all this kind of work, badass as it looks. I just really hate doors. Sliding canopy and water resistant interior FTW.

[beatersubi]

If you didn't live so damn far away your place would be my second home. Hey, whats the economy like in Co these days?
Are you gonna do a horizontal across the main hood for harness attachment?

[SLODRIVE]

The economy is pretty good here in CO, I'm not going anywhere soon. I recently visited the PNW for the first time this spring, and it's my second favorite area now. Colorado being the first.

I'm making the harness bar now, I'll have more pics in a bit!

[SLODRIVE]

Here's how I wanted to run a second diagonal, from the main hoop's passenger side to the bottom of the driver's side rear support. This way, it'll also triangulate the crap out of the rear of the car, and still give more rollover protection for a passenger. I may also run another bar straight across at the strut towers, but I'm going to see how it does without it. You can still carry a sofa as it is. Maybe just a standard strut bar?

Here's the harness bar installed.

[beatersubi]

The economy is pretty good here in CO, I'm not going anywhere soon. I recently visited the PNW for the first time this spring, and it's my second favorite area now. Colorado being the first.

I'm making the harness bar now, I'll have more pics in a bit!

I've been looking for an excuse to get the hell outta here. The local gubm'nt is really starting to get on my nerves. They recently instituted an extra tax on beer (among many other things), but only macro-brews, to try to catch up to their overspending problem. Talk about messing w/ the working class...

But I digress. Cage is looking awesome. I've seen cages w/ main hoop X's and X's to the rear struts. Thats overbuilt IMO, but something to consider. I'm going to be using yours as a tutorial for mine, so don't mess it up!

[SLODRIVE]

I wasn't sure how the door bars were going to turn out. As a matter of fact, I'm still not 100% sure...but I got the lower bars done on both sides. I kicked them out 3 inches for seat clearance, and as luck would have it, the door panels still clear after removing the pockets.




I'm still unsure how I'm going to do the upper door bars. Being that this car is going back on the streets for now, I don't want anything too high. I'm also undecided on whether I'm going to push the upper bars quite as far out either. We'll probably find out tomorrow!

[evolutionmovement]

Too bad the doors couldn't be cut into the roof GT40-style so you could step over the higher door bar. Or . . . have a sliding canopy in lieu of doors. Friggin' doors.

[kimokalihi]

What type of metal are you using? Will it rust? Could you paint it if you wanted to?

[beatersubi]

You might wanna check NASA/RA cage specs (if that is what you're building to) as I'm pretty sure they don't like bent door bars. I also think they only require 1.5" for anything other than the main hoop structure. There's a lot of good info on cage building over on the DI.

[SILINC3R]

cant wait to see the finished product

[SLODRIVE]

You might wanna check NASA/RA cage specs (if that is what you're building to) as I'm pretty sure they don't like bent door bars. I also think they only require 1.5" for anything other than the main hoop structure. There's a lot of good info on cage building over on the DI.

This cage is being built to NASA specs, as a matter of fact. There is nothing in their rules prohibiting bent door bars; in fact they're preferred/safer for 2 reasons: 1) they provide additional side-impact protection due to the outward bends; and 2) In a HARD front-end collision, the bars tend to bend away from the driver/passenger, rather than towards them.

As far as the tube size, yes I only need 1.5" for a sub-3000# vehicle, but I'll get over that, especially since this car may well top that weight with the cage. I started out with a 1.75" die because most of the road racers (excepting the Miata and 944 guys) have 3000+ pound cars, and also because my next cage is for a Cherokee racing in the 24 Hours of Lemons. By the way, you have to use the approved size/thickness of tubing for the whole cage.

Kimo, the cage is mild steel tubing. Yes it'll rust, and yes, it'll get painted!

P.S. What's the DI?

[evolutionmovement]

Yeah, the bent door bar is similar in idea to the vehicle I'm building where the frame is a double set of bow shaped tubes that in plan view resemble a kayak and in elevation will be at heights similar to a set of two door bars with the higher bar requiring a step over (hence my obsession with sliding canopies). The idea is that the bend increases strength over straight and the forces from a collision in any direction are always distributed away from the cockpit. It also happens to be aerodynamically efficient.

[beatersubi]

I understand the theory of side intrusion protection, but hadn't considered the front collision aspect of the design.
I'm also pretty sure RA only requires 1.75" for the main hoops. I'll have to go back over the rulebook. Not that bigger/stronger is necessarily worse, of course.
http://dirtyimpreza.com/

[SLODRIVE]

^^^ I'm not building this car to Rally America specs, now I see what you're talking about. Rally's dead here in CO (it died while I was building the white SS), so this is more as a road-racing cage. And they like the same size tubing all through the cage.

Oh yeah, I figured out what DI is...I signed up this weekend. Thanks for the tip

[SLODRIVE]

Hmmm?