OP
bulletpruf
Well-known member
Pics of the finished product attached. Now, everyone repeat after me, "Grinder and paint makes me the welder that I ain't!"
Roll Cage Installation Tips?
- Thread starter bulletpruf
- Start date
Hellpig
Well-known member
Dave G in Gansevoort
Well-known member
Yeah, there’s my way, and then there’s an easier way! I always choose the path of most resistance. I have an excuse however. I had a good shell that had a couple of dents in the roof, and I had a shell with a good roof and not much else. And Minis have the seams on the outside. It was actually pretty easy. Sawzall for as close to the seams on each shell as possible, then grind away the offending parts. You’d have to see it to understand how easy it really was.
iagsxr
Well-known member
What did the chassis do when you removed the roof?
I would expect a unibody car to deform quite a bit with the roof off.
Hellpig
Well-known member
Can't count the times I've done something complex and difficult, stood their beaming, proud as a peacock, only to have someone say, " Nice, but why didn't you just XYZ?"
Oh, well getting there sometimes IS the best part!
zimman
Well-known member
Pics of the finished product attached. Now, everyone repeat after me, "Grinder and paint makes me the welder that I ain't!"
Hammer to fit, paint to match. LMAO
Nice work.
Zim
Hohn
Well-known member
I have to ask.
Is it because of residual stress from a full bead?
Hohn
Well-known member
It's a way of life for some of us. Not only doing it the harder way, but often having to REDO it because the harder way failed. I resemble that.
"If it ain't broke, it's because I haven't fixed it yet."
Ohmthis
Well-known member
Looks nice!I assume the gray metal is a new floor pan area?Pics of the finished product attached. Now, everyone repeat after me, "Grinder and paint makes me the welder that I ain't!"
Dave G in Gansevoort
Well-known member
The cage was already half welded into the shell, tied into the firewall, the subframe attaching points, the rear bulkhead, and the door posts. It doesn’t seem to have moved at all in any way. Doors still open and close properly. And I just needed to get to the top of the main hoop and the halo tube. So yeah, those riser blocks would have saved a lot of time and energy…
kerrynzl
Well-known member
Stitch welding allows the floor to deform instead of tearing off along the edge .
When you get a very rigid [floor plate] fully welded to a thin floor you create a stress point [which cracks] if there is any compliance
Seam welding [stitching] is a very common method of stiffening a unibody car for competition.
I highly recommend that @bulletpruf stitch welds along the rocker panels, the stock towers in the front and rear, door openings, windshield/rear window frames and inner fender/firewall.
This would achieve far more than adding subframe connectors
seam welding increases torsional stiffness whereas a ladder frame [including subframe connecters] only increases beaming strength
My race car has over 2000 stitch welds in it [built like that at the factory]
Also @bulletpruf I highly recommend you add a piece of roll cage tubing from the A to B pillar hoops along the bottom of the door opening.
Then add 2 x perpendicular pieces to this [to the tunnel] to mount the seat. For safety it is better to mount the seat to the cage.
And also mount all the harness points to the cage if possible
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I witnessed a NZV8 touring car that got "T-Boned" in the drivers door at a full 70mph [first corner spin] The shunt was that hard it crushed the tunnel and spat the transmission downwards when the seat moved laterally with the cage.
The driver got a broken hip but he survived.
Incidentally this car was noted in the logbook for having a non-regulation cage and door bars [that had to be changed] but these were what saved his life [and the rules for this class were later altered]
The door bars were not the traditional "X" that were required but 2 x "U" bars welded together [back to back]. U bars do not have cuts/joins and are stronger.
Rally cars use this method of door bars [because they have a propensity for attacking trees]
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iagsxr
Well-known member
Seat mounts as well.
kerrynzl
Well-known member
Yes ,absolutely! [I wrote that in the line above]
I know [or knew] a rally car navigator that got killed when they collected a tree between the door and rear wheel at high speed.
The rear half of the car separated from the front [which included the cage and seat]
Unfortunately the shoulder straps of the harness were anchored to the floor, so when the rear separated he suffered from crushed ribcage/internal injuries from the harness.
It was a terrible price to pay for us to learn a lesson
iagsxr
Well-known member
My bad, I missed that.
OP
bulletpruf
Well-known member
Correct. I wanted to get the subframe connectors in place before I started on the floor pans. Once the floors are done, I'll work on the cage install.
Ohmthis
Well-known member
Bulletpruf, you guys are so a ton of work quickly! I’m enjoying watching you guys!
I'm not going to argue with Kerry on cage installation but I will say this. Figure out what sanctioning body you are racing/driving with, research their rules and build your cage specific to those rules.
4 FN 27
ALLIANCE MEMBER
This!!!
Back in the day we had an area NHRA Chassis Cert guy that basically did "Drive-by" Certifications. When he was asked to step down and the new guy took over I had 2 years worth of work replacing incorrect Bars and finishing welds that didn't go all the way around the Tubes.
This was what I cut out of the worst car I re-did.
I had to replace both diagonal bars with the correct thickness tubing. While cutting the passenger side out something fell and hit me in the back of the head. Looked like some kind of hard plastic. It was JB Weld smeared across the tops where they could not get in to weld.
I ended up replacing the whole Cage. This was a car that ran in competition running mid 8 seconds.
I did the work in 2002. Took the pics in 2023. The new Chassis Cert guys carries this node with still to this day to show people.
Don't be this guy!!!!
Be this guy:
I did this cage back in the day and he had another shop update it adding the Funny Car portion and Kidney Bar.
OP
bulletpruf
Well-known member
Well, it feels like it's going very slowly to me, especially when we need to be ready for the first race in early November!
OP
bulletpruf
Well-known member
24 Hours of Lemons. Cage builder has done a BUNCH of cages for this series so he built it with that in mind. We have detailed instructions from the cage builder and rules from Lemons.
Thanks
OP
bulletpruf
Well-known member
This!!!
Back in the day we had an area NHRA Chassis Cert guy that basically did "Drive-by" Certifications. When he was asked to step down and the new guy took over I had 2 years worth of work replacing incorrect Bars and finishing welds that didn't go all the way around the Tubes.
This was what I cut out of the worst car I re-did.
I had to replace both diagonal bars with the correct thickness tubing. While cutting the passenger side out something fell and hit me in the back of the head. Looked like some kind of hard plastic. It was JB Weld smeared across the tops where they could not get in to weld.
I ended up replacing the whole Cage. This was a car that ran in competition running mid 8 seconds.
I did the work in 2002. Took the pics in 2023. The new Chassis Cert guys carries this node with still to this day to show people.
Don't be this guy!!!!
Be this guy:
I did this cage back in the day and he had another shop update it adding the Funny Car portion and Kidney Bar.
Damn, that looks like some of my welding!
Good thing my buddy Lee will end up welding up the cage. He's a former Top Fuel mechanic, fabricator, and welder.
M.Brane
ALLIANCE MEMBER
Yes, but if you ever want to run Champ Car there's stuff you've done that will get you points toward your value like the subframe connectors, and any additional chassis stiffening.
iagsxr
Well-known member
When I was looking at building a Lemons car it was pointed out to me that a lot of oval track builders cages fail tech because they haven't read the rules.
There are some things in the rules that I'd argue over or at least make someone explain the reasoning behind.
In the end though, it's their circus, you're their monkey. They've ran hundreds of races and I'm sure seen situations I haven't even thought about. Just do it the way they tell you to. The tech guy usually wins every argument.
kerrynzl
Well-known member
There is so much truth to this.^^^
Try and find the guy who certs the cages and "stroke their ego" [a lot of these guys are unpaid officials, that like to be important]
Ask for advice before you weld the cage into the car.
I went through a bit of ******** with a Mustang FR500C [SCCA Grand-Am] car I imported to NZ.
When it came to getting the cage homologated , they wouldn't cert it because it had NASCAR style door bars [which I don't particularly like]
Motorsport NZ and the SCCA are both affiliated with the FIA, so I could've simply gotten a motorsport "passport" and raced with the SCCA logbook. [international drivers do this frequently]
But that gets worse , I would need an international grade race license, new race suit, gloves, shoes, helmet, HANS [yet my equipment is perfectly OK to use anywhere in the world IF I used their local racing license ]
It would've been cheaper to cut the cage out and make a new one than buy all the required equipment.
I had a stroke of luck, with the research of my car. Ford had actually campaigned them in Europe [FIA group 4 touring cars] so I emailed them to ask for info.
They were identical, So they emailed me all their drawings, homologation certificates, engineering calculations etc etc [way too much information]
NZD $50 [USD $30] later the car has a Logbook.[it has 2 logbooks]
I know of a BTTC touring car that was imported [that was brand new and never raced] so it never had a logbook or any specs on the cage [no paperwork] They basically needed to build a whole new cage.
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Ohmthis
Well-known member
I can understand with a deadline looming over you that it would feel that way. Just keep on trucking and you’ll be fine!………..Said the guy who’s never put one of these cars together
zimman
Well-known member
Same problem I'm coming up with is "track day" certs. I've done a dozen of 8.50/25.5/23.3 SFI cages. I asked a question about the track day stuff and they told me most drag racing SFI will be okay but the faster classes will have problems with the door bars. They're different somehow. Puzzles me how a drag car being hit midships at 200 mph is different than getting broadsided at 200mph on the apex of a corner. LMAO.
Zim
OP
bulletpruf
Well-known member
Yep, that's the plan. The guy helping with the cage has been racing Lemons for several years, too.
OP
bulletpruf
Well-known member
The main tech guy in Lemons is John Pagel. There's a Facebook group that I'm a member of named, "Unless John Pagel Signs Off, This is Probably a Bad Idea." Lots of helpful folks there, and John posts regularly, as well. https://www.facebook.com/groups/2218397518440508
OP
bulletpruf
Well-known member
I can understand with a deadline looming over you that it would feel that way. Just keep on trucking and you’ll be fine!………..Said the guy who’s never put one of these cars together
We will try to meet the deadline, but the emphasis is on doing it right. That trumps the timeline.
OP
bulletpruf
Well-known member
If someone gets broadsided in a corner in a Lemons Race at 200 mph, something has gone horribly wrong! Looks like top speed should be around 120 mph, depending on the track. That's in general, not necessarily for my car. https://forums.24hoursoflemons.com/viewtopic.php?id=30190
zimman
Well-known member
I was being a little hypothetical. LOL
Zim
OP
bulletpruf
Well-known member
Yeah, I know.
But it reminded me that I needed to do the math on what our top speed should be. With 3.54 gears, 1:1 4th gear, and 275/40/17's (25.6" tall), we would hit redline (5,500 rpm) at 120 mph. I haven't purchased the ring and pinion yet and still not sure on tires (might end up doing 255's on late model Mustang 17x8's) so things may change slightly.
txvwnut
Well-known member
I've built two cages for a guy that got into Lemon's racing. The first time he went through tech the inspectors were amazed that I read the rule book and got it right. My customer said he looked at about dozen or more cars that came through tech and none of them had a one piece A hoop, which was stated in the rule book as a must have and what he had in his cars.
aka Larry
Well-known member
Reading is hard.
The 24HOL rule book is very short and to the point. It has changed over the years, but it's still super easy to follow. I've built/helped build five cages and had no issues at tech.
That said, you can never underestimate the level of stupid out there. I was once pitted beside a team that had their roll bar padding on the OUTSIDE of the bars.
I was watching that same team attempting to belt in their driver and the camlock belt buckle was in the middle of the guys chest!!!! I couldn't just watch someone do something that might get them hurt, so I went over and helped them get their padding and belts installed properly. I get it that sometimes "you don't know what you don't know", but in today's world all the information is super easy to find online, and when that fails, you could just ask one of the other 99 teams at the race...geez!
jayz66ragtop
Well-known member
May not help much for the OP, best advice we got was find someone who builds off road cages. I didn't know it at the time but apparently there are many different rules and regulations based on the sanctioning body so they have to adjust based on what class/rule set they are given.
Sure enough MOST of them build good, strong cages and if provided with a rule book/specifications will build it to that.
Sure enough MOST of them build good, strong cages and if provided with a rule book/specifications will build it to that.
zimman
Well-known member
Where can I find said rule book? On line or for purchase.
Zim
txvwnut
Well-known member
I had to dig for it on line and I think I found what I needed to know through a forum post. The customer brought a couple of printed pages along with some information on it that he got from a forum post. I showed him my circle track car that I built and said from the looks of it we can get away this type of cage and you'll be plenty safe, so that's what I built him.
zimman
Well-known member
I was just on the SFI foundation website and they list the sanctioning bodies but it's a dead end. Has to be a book out there somewhere especially if NASCAR can run track events. You can find specs for helmets, belts, socks, antenna's and such LOL but not the cage?
aka Larry
Well-known member
txvwnut
Well-known member
When Alex and Dennis Taylor built the 55 he had a book that showed the type of setup they would need for the speeds they were building to, I want to say it was an SFI book but it could've been something from NHRA. A lot of what I learned is from other sanctioning bodies rules and just seeing the cages in the cars.