A Discussion About Roll Bars
by Bruce Meyers
Three or four years ago I received by post, a beautiful new book from my English friend and author, Keith Seume. On its cover was the title “VW Beetle – The New Custom Handbook”. On the first page was the authors handwritten words – ‘To Bruce and Winnie – Keep On Buggin!” – Keith Seume. Keith ‘s books are always beautiful and absolutely top priority reading. Aesthetically handsome with four colour photography, they are highly technical and concise, and why not? Keith is highly technical and concise. Erudite and urbane as only an English gentleman can be, one senses in him a huge intellect that controls a restrained wit. Keith created and once was the publisher of the British VW enthusiast magazine ‘Volksworld’ for many years.
In this new book is a chapter called “Buggying About” with its subtitle “the Most Fun You Can Have On Four Wheels”. Now, I know personally that Keith is a fun kind of guy, and loves a good laugh. Once while dining in the quaint sea-side village of Lege-Cap-Ferret in France, Keith and I were ‘pigging out’ on pots of steamed mussels with the freshest of french rolls used to soak up the to-die-for wine/cream sauce at the bottom of the pot. Followed by a glass or two of the usual Bordeaux wine, I managed to break through Keith’s controlled English restraint with my ‘air-sick old woman traveler who lost her false teeth down the toilet’ story. The vision of the punchline evaporated his restrained demeanor and with his British propriety aside, he fell into a fit of squirming in disgust broken by howls of laughter, while dozens of restaurant patrons curiously watched. Now, that’s more like it, Keith.
I haven’t read the whole book yet, but I have read the sixteen pages of the “Buggying About” chapter and I’m impressed at how organized Keith’s work is. As the editor of ‘Volksworld” for so long, he must have written about buggies many times to have so much to say on the subject. Of course in England a buggy is not used like we use them here and so they have a different perception, in fact, they are referred to as ‘Beach Buggies’ instead of Dune Buggies. England has no Baja or deserts and even less big sand dunes so the off-road aspect of the buggy seems to be more important to us than it is to them. In spite of this understandable European view, this is a very thorough summary of what buggies are all about and this chapter of Keith Seume’s book has arguably one of the best-ever collections of street-type buggy portraits you will find anywhere. I recommend it!
As I read on, I came to Keith’s thoughts on safety. “On the subject of safety, there is one aspect of a well conceived buggy which we must emphasize: The roll cage. In the past, all too many buggies have been built either without driver protection of any kind or with a next-to-useless single roll over hoop. While it could be argued that anything is better than nothing, A single unsupported roll-bar will do little to protect the driver and passengers in the event of a roll-over accident. Without any form of bracing, the hoop will simply collapse, leaving the occupants highly vulnerable and exposed to injury”. Yes, the driving public has been media-blitzed about safety, and rightly so. Since I created the Meyers Manx thirty-nine years ago, roll cages have appeared in increasing numbers. The new Manxes (ie. long wheelebase Manxter) of the future are planned with them as an integral part of the design. Keith’s remarks about ‘collapsing single hoops’, and `next to useless’, sound pretty scary, don’t they? I have a lot of years and miles on this subject that perhaps my English friend does not. So, let me reminisce about upside-down dune buggies.
When the first single hoop roll-bars appeared, they seemed to be only a simple foundation for a top. Like all simple things there is the mistaken perception that it was dashed off, without design or thought. Actually, simplicity is the result of much paring down of extraneous elements until only the really important things remain. The original Meyers Manx roll-bar has had to prove itself several times. It is made from a 2 inch diameter X .120 wall thickness, mild steel round tube. Its bracketry has been carefully planned and if properly installed can be trusted to keep the car off of its occupants – short of the worst kind of catastrophe.
The first time I became inverted, was while playing in the biggest kind of sand dunes at a place called Buttercup in California. The sun was low in the afternoon and a group of us were shooting bowls, that is racing around clockwise inside a huge sand bowl of several hundred feet diameter at speeds of about 40-50 mph. Diving into the bowl was to drive into the shaded, steep side of the bowl, to circulate around, like the ball of a roulette wheel. When coming out onto the less steep side of the bowl and into the sun, I kept flipping my dark glasses up onto my forehead and down again as needed to see into the glare. I had taped an old fashioned bamboo pole with flag, to the passenger end of the roll-bar, the passenger being my (first) wife, Shirley. While tearing along the crest of the next dune downwind, to my left, and watching the guys in the other cars, to my right, I drove off the crest at about 30mph. As I left the crest on a diagonal line, the car corkscrewed through the air, dumping Shirley and I out of our seats. As we landed face first in the soft sand, the car followed us upside down. I had fallen out of my seat with no seatbelt and my head was near the roll-bar. As we hit, the roll-bar pushed my head into the soft sand and at the same time the bamboo pole at the other end of the roll-bar broke. My skull was hard against the steel roll bar which transmitted the crunching sound of the bamboo breaking, only I thought it was my skull crunching. The car continued on, flopping up onto its wheels with its front wheels jammed hard right into the sand and a mound of moist sand piled on top of a front fender that had dug deep into the dune. The broken bamboo pole was draped over a rear fender. The buggy sat quietly, engine off, like it had just been scolded. There was no other damage to the car including the intact roll-bar. My dark glasses had been smashed against my head with bits of glass in my scalp. I was in shock as I scrambled over to Shirley and she was motionless, lying face down in the sand. I didn’t want to make things worse by moving her, but I yelled “Shirley, Shirley”, whereupon she slowly turned her face from the sand saying that she was OK, though she thought she was dead until she heard me yelling. We were both still in shock as we drove back to our friends, me thinking about the usefulness of seatbelts. This happened in ‘Old Red’ the very first Meyers Manx.
Come to think of it, Old Red and I got upside down twice. The other time was on a rainy Sunday in the bluffs of the back bay of Newport Beach before all those condominiums were built. A couple of Manx Mania issues back, I was telling the story of ‘Quatro’, My Personal Manx, and there is a picture of Quatro driven by its original owner climbing a very steep, muddy little hill. I had attempted the hill in Old Red and on one try stood the car straight up, balanced precariously on its two rear wheels and exhaust pipe, like a kangaroo stands on feet and tail. I hugged the steering wheel close to my chest, so as not to fall over backwards, and yelled to those spectating below to get up here and pull the front end of Old Red back down. Everybody scrambled up the steep muddy slope – Shirley got there first, and reaching up to the front bumper, pulled, but instead of pulling Old Red down, slipped in the mud and slid under the buggy. The next guy behind her decided Shirley’s safety over mine and pushed the Manx on over backwards with me in it. Over I went. Old Red and I doing a backwards somersault. The car landed on its wheels, the folks scrambled off the muddy hill laughing with the guy who pushed me over backwards. The only damage was a broken tail light lens!
Old Red was the first of the twelve monocoque’s (no floorpan) entirely made of fiberglass with steel tube sub¬structures laminated to the outside of the body tub as attachments for the running gear. However, the roll-bar was thru-bolted to the fiberglass body tub only at the lower inside corners and at the upper side-walls. Using 3/8″ dia. bolts and small metal plates or fender washers on the outside. My long years of ocean racing sailboat construction had taught me the wonderful tensile and shear strength of fiberglass. For instance, the wind tries to capsize a sailboat by pushing the mast with its sails sideways. The mast is supported by relatively tiny diameter wires that are in direct tension attached to metal straps called ‘chain plates’. These are through-bolted with a handful of bolts to the fiberglass hull. These bolts are in a kind of stress called ‘shear’ as the fiberglass is trying to shear them in two. The fiberglass hull is a shear panel that lifts the many thousands of pounds of lead ballast that is the yacht’s keel. The hull and chainplate attachment on a yacht is exactly the same as the fiberglass body of a Meyers Manx dune buggy and it’s correctly installed roll-bar, and the buggy has no keel to lift.
Other times I was told of incidents by my friends, two of which were nearly identical. Once Peter Rothchild (his ancestors financed Napoleon – I am told!) was traveling fast down a desert dry-wash dirt track broadsliding the turns. A drywash is normally quite smooth running its length. But the rivulets of water during rains often cut small but severe little vertical walls like a street curb. Broadsliding against these will surely dump the playful driver on his head. This happened and Rothchild rolled his Corvair powered Manx, bending the windshield frame back against the steering wheel and cutting his knuckles on broken glass. Another time Ted Mangels did the same thing in a Baja dry-wash only slower and just gently flopped the car on its side, no damage to the car – only bumps and bruises.
The most violent tale of this kind comes from a guy who driving along a trail at the top of a 100ft cliff above the beach at night, (I’m frightened already!), he had a 16 year old neighbor girl in the passenger seat and his 16 year old daughter riding in the back, holding onto the roll-bar. Happily they were all in seatbelts. Driving much too fast, he couldn’t avoid rocketing off the cliff, thankfully not to the distant beach below, instead into a deep canyon. The Manx sailed fifty feet, nose high, tail heavy, hitting the canyon wall, rearwards on its exhaust system. It then fell twenty-five or thirty more feet into the narrower canyon crevasse below, upside down! The buggy was crammed – wedged between canyon walls, its intact roll¬bar providing enough space to keep them from being squashed. Broken facial bones, teeth knocked out, acid burns from the battery, they fell even further when they released their seat¬belts. They did manage to climb out of the canyon on their own. The roll-bar didn’t collapse, providing an extra margin of safety and the only positive factor to this traumatic event.
A properly installed roll-bar in a Meyers Manx, has a very important little bracket that attaches to the torsion bar housing outside of the body. A bolt passes through this into the lower roll¬bar weldment, sandwiching the fiberglass body enroute. The upper roll-bar weldment is bolted to the body side panel which is like the sailboat hull, a very good shear panel. Now, the rollbar can’t be yanked out or shoved down into the car by its attachments to the sides of the car. The bottom of the roll-bar is bolted to the torsion bar housing, the largest, heaviest chassis component in a Volkswagen’s floorpan. If the steel tubing of the roll-bar is of such wall thickness and girth of tube, to be used in such relatively small perimeter outlines (about 31/2 ft), then it should not parallelogram, distort, or in Keith Seume’s words – collapse. In none of the foregoing stories was there any sign of roll-bar failure in any way. Not a cracked weld, a bent bracket, a distorted tube or even torn or cracked fiberglass.
Maybe in all these incidents we’ve been lucky – it could have been worse. But all these roll-bars had been correctly installed. I see so many horror stories of bad roll bar attachments. People obviously see the fiberglass as something akin to a plastic wastebasket, structurally useless like a cheap plastic toy or even worse. They avoid the correct use of the fiberglass (it’s tensile and shear strength), preferring to plop the feet of their roll-bar or rollcage directly on top of the sheet-metal floor (which is about as thin as paper) and with enough force tears like paper. At least they could mount it in the lower comer on top of the fiberglass where it’s bolted to the pan, thereby taking advantage of the shear-panel effect of the glass body.
Once again, I’d like to regale you with a story of a roll-cage mounted on the sheet-metal only. Once, after dark, there were several Manxes and a V-8 powered, monster tyred Jeep bringing up the rear. The first Manx approached a sheer, straight-down bluff – but only for about three or four feet straight down. Then it was a sandy slope of about 75-80 ft to the road below. So the Manxes all gingerly slid over the edge until the front wheels found the slope and descended safely. When the Jeep attempted the same feat, everybody yelled not to. “No Harold, no, don’t try it”, but Harold had to save face. The Jeep’s headlights came over the rim, gently arched over, doing two complete somersaults and landed on his wheels directly in front of us. Harold and his girlfriend were OK, but the Jeep’s body was demolished. The complete roll-cage was mounted on top of the floor in front, and on the raised wheel wells in the rear. The roll¬cage was OK but had poked right through, sitting on top of the rear tires, and hung inches above the ground in the front. Nothing had been attached to the frame – just the sheet-metal. Great roll-cage, sheet-metal used improperly.
I’ve had fun with these stories and I might even dredge up a couple more, but why? I think you get the point. Keith Seume, you’re one of my favorite people – a tad innocent of all this perhaps. Why don’t we go ‘pig out’ on another pot of mussels and Bordeaux wine. Au revoir. Hiccc!
By Bruce Meyers
A Discussion About Roll Bars