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Deluxe Ladder-Based Rack for Pontiac Vibe/Toyota Matrix

by J-J Coté

Vibe loaded.JPG

This rack has two configurations: a simple one for carrying a single glider, or a fancier one for carrying up to three gliders. It requires no modification to the car, costs very little, is rock solid, and goes on and off quite quickly.

Vibe alone.JPG

Here's the starting point: a 2003 Pontiac Vibe, with factory roof rack and sunroof. The sunroof is not essential, though it does make one step easier for the fancier rack configuration. The factory roof rack helps quite a bit. In early years of production, at least, the Vibe came with the rack, but the Matrix did not. I believe the rack is now also available on the Matrix. The rack originally came with two transverse bars, which I believe have since been eliminated, but it would be simple enough to add an aftermarket bar if the rails are there.

Configuration #1: Ladder rack for one glider

Vibe rails.JPG

The first step is to slide both factory bars as far back as they'll go. The front bar is slightly higher than the rear one, because the rails aren't level, so only the front rail will initially be used. In some sense, it would be better to remove the front bar , but it's not obvious how to do that. The front bar has two hose clamps around it, spaced at exactly the width of the ladder. These keep the ladder from sliding side-to-side, and also make it very simple to get the ladder centered when putting it on the roof. There are a couple of pieces of rubber under the clamps that extend inward to give a little bit of damping between the ladder and the bar.

Vibe yak.JPG

The other support for the ladder is a Yakima bar that I got from ebay. It goes just behind the windshield, in the location that puts the bar at the same height as the factory bar. Inside the door well, there are marks made with a silver sharpie pen to show where the clamps go, in order to make it easy to put the bar in the proper place. This picture shows the marks just before moving the bar clamp into position.

Vibe bars.JPG

This picture shows the roof attachments ready for the ladder. The objective is to have two bars at the same level spaced as far apart as possible. Since the Vibe is sort of a little station wagon, it has a decent amount of roof and the spacing is pretty good. The Yakima bar has a pair of SnapArounds, spaced at ladder width just like the hose clamps.

Vibe widget.JPG

Here's a custom piece of engineering, made from wood because it's easy to work with. This widget primarily serves to make sure that the ladder can't slide forward or backward during braking or acceleration, but also puts some of the load on the rear (lower) factory bar. The two notches on the bottom are spaced to match the bars, and the upper one fits around a ladder rung.

Vibe widgets.JPG

The widgets are placed onto the roof before the ladder. If I'm taking just one glider, I usually use only one widget. When I first built the rack, I didn't have any widgets, and it worked acceptably. The widgets actually go on a bit further apart than shown here, so that they're flush against the side of the ladder, but putting them on like this makes it easier to get the ladder into position, and they can then be slid outward to where they belong.

Vibe straps.JPG

Here's the ladder in place. I was very fortunate to pick up this 32-foot Type II ladder on craigslist for only $30 (the other half is in my garage, waiting for another use). It's secured with four nylon bicycle toestraps, two on each bar. An old friend of mine would probably say that the ladder is really held in place with "British glue", i.e. gravity, which is what he maintained that MGs and Triumphs were held together with. Once it's loaded up, the ladder isn't going anywhere, and the toestraps are just to keep it from bouncing when the car goes over a bump. Each ladder rung is covered with pipe insulation, with a strip of Gorilla tape on each end. The rung on the left has ductape that I put on a couple of years ago, that clearly needs replacing. The radio antenna is in an inconvenient spot, but it's flexible enough that it can just fold down under the ladder (with some loss of effectiveness).

Vibe ropes.JPG

There's quite a bit of ladder hanging out in front of the front bar, so as added security in case of crosswinds or big bumps, crossed ropes are used, connecting to the towing eyes under the front of the car. Note that the ropes have to be diagonal to help in case of side loads, as a vertical rope would do nothing (but would help in terms of bumps). The ropes have taut-line hitches to make them easy to adjust. (The white tubing around the rope just above the knot on the right is for when I use this same rope to transport a canoe on the roof of the car.)

Vibe biner.JPG

The ropes connect quickly to the towing eyes courtesy of carabiners. I haven't made much use of my climbing gear lately, so at least these pieces are serving a good purpose.

Vibe basic.JPG

The ladder is now securely on the roof. Setting this up takes probably about five minutes. Note that the sides of the ladder are covered with ductape. This is to keep the rungs from acting like organ pipes and howling as the car goes down the highway. I recommend one long strip, rather than a little patch for each rung. A friend of mine claims that you only need to do the front half of the ladder, because you can't hear the rungs that are behind you, but I haven't tested that to know if it's true. There are also some strips of tape in contrasting colors on the side as a visual guide to help me align things fore-aft.

Vibe oneglider.JPG

Ready to roll with one glider. The glider is secured with a pair of 1-inch straps, each of which goes over the glider twice (and under two rungs). No claims that these straps are superior to any other lashing method, but they're simple and cheap and work well enough. I've made many trips with this simple ladder rack, and it's even possible to squeeze two skinny gliders (e.g. Falcons) onto the ladder.

Configuration #2: Deluxe rack for up to three gliders

The simple ladder rack is all well and good if I'm the only one bringing a glider, but sometime I get a chance to carpool with other pilots, and it's good to be able to carry more gliders. In that case, it's time to add accessories.

Vive extenders.JPG

The first accessory is the extenders. These are each made from a 1x3, with a pool noodle on top, and the whole thing wrapped in Gorilla tape. End plates keep the gliders and/or straps from sliding off, and the bolts, wingnuts, and lower board secure the extenders to the ladder.

Vibe extender.JPG

Detail of one extender in place on the ladder. Thee lower board can fit down between the rungs when turned diagonally, then it gets straightened out, snugged up against a rung, and the wingnuts tightened.

Vibe extenderson.JPG

Normally one extender goes at the front of the ladder, one at the back, and the third just above the front seats (the sunroof makes it easy to tighten the wingnuts on this one). If I'm carrying shorter gliders, the front and/or rear extenders can be moved in closer.

Vibe nobumper.JPG

There is a problem now, though. With multiple gliders on this rack, there's enough mass forward of the front rack bar that going over a bump results in some substantial pitch oscillation of the ladder. What's needed is another support in front, maybe going to the bumper. Unfortunately, the Vibe doesn't have any kind of bumper or similar horizontal surface out front to rest anything on. I considered trying to tie into the towing eyes with something that could take a compression load, but it wasn't obvious how to do that.

Vibe brace.JPG

This is the solution. This is the most involved and expensive part of the rack. Most of these piece are 80/20 ("The Industrial Erector Set")[1], which a company that I do work for uses extensively. The aluminum bars cost $0.41 per inch, and the various connectors cost between $1 and $5 each. The double suction cup handles are $5 each from Harbor Freight, and the clamps that connect the handles to the horizontal bar are completely custom (adapted from something that I found in the junk box at work). So there's probably at least $70 worth of hardware in this strut, plus some work to get it all assembled. Still not too bad.

Vibe braceon.JPG

Here's the brace in position on the hood of the car. This is the only piece that requires use of a tool, an Allen wrench to tighten the clamps that hold onto the ladder flanges. It's not simple to find a place where the suction cups on a handle can both sit flat on the hood, and even this spot isn't perfect, but it's close. Sometimes one of the cups will lose its grip in transit, but that's not a big deal, since the force is mostly downward, and the suction cups are largely just serving as pads. Note the mark on the side of the ladder to show where the clamp goes. I've also made small dots on the hood with a silver sharpie pen to show where the suction cups go. Not everyone would want to deface the paint job of their nice shiny car like that, but this Vibe has 231000 miles on it at this point, so who cares. (It seems possible that this could be the highest mileage Vibe in existence!) With the front brace, I don't bother to use the crossed ropes.

Vibe threegliders.JPG

All loaded up! That's a Vision MkIV, an Ultrasport, and a Falcon, for a total of about 190 pounds. I've only done a 45-minute shakedown test on secondary roads with this load, and it was fine. I have done an 8-hour round trip on the highway with the Ultrasport and a Lightspeed (total about 150 pounds), and I hardly knew anything was up there. The full load that I have in mind is the Ultrasport and two Lightspeeds (about 225 pounds) with three people in the car, and I expect that will be fine, though I do anticipate having to downshift a fair bit when climbing hills (this car has the small 1.8 liter engine).

The Vibe gets about 34 mpg with no rack, and believe it or not, with the basic rack and a single glider, the gas mileage is barely affected. With the extenders and two gliders, there's enough drag that it drops to 26-28 mpg. I expect that it will be about the same with three gliders. Pretty good, I think.