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Model A Frame Of My Modified ProjectThe Modified Gets Shock Absorbers And Steering From the October, 2011 issue of Rod & Custom By Kev Elliott
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We left off last month with the front axle and springs mounted to the Model A frame of my Modified project, which means the next logical step is steering and shock absorbers. With a normal cross spring-suspended I-beam, selecting steering arms and the tie rod is pretty straightforward, as there’s usually only one place the tie rod will fit; under (or through) the radius rods and under the chassis. The choice of cross steering, with something like a Vega box and universal joints connecting the steering column, or a solid column and box, such as an F-1 or stock ’32-34 box, will determine whether or not you’ll use a drag link from the left-hand spindle leading back to the steering box and pitman arm or not. Here’s where I left off last... Here’s where I left off last month, with the axle, split wishbones, and springs in place, except the project moved from our Tech Center to my home garage in the interim. Now it’s time to hook up the steering. I’m aiming to build this roadster with as vintage an appearance as possible while using some new parts, so I opted for a solid column and box (which I have yet to source) and a drag link. Not wanting to place my tie rod ahead of the axle, out in front where it could suffer damage, meant it had to run across above the split wishbones, as well as over the quarter-elliptical springs I’d chosen to use. This meant careful selection of steering arms to ensure no interference between the tie rods and other components. I was lucky enough that Vintage Reproduction Parts sent me three sets of steering arms to make my selection from, and now I have done just that. I know this is something not everyone can do, so hopefully my following findings will help with selection for your projects. Vintage Reproduction Parts... Vintage Reproduction Parts supplied me with three different steering arms to see which set would suit my project best. First up, a 3 3/4-inch dropped pair intended for ’35-48 Fords. While the tie rod cleared the wishbones, it touched the leaf springs. Next! OK, onto the shock absorbers. Modern thinking would dictate tubular shocks, which are available these days with built-in and/or adjustable compression and rebound adjustment (check out Rob’s Fleetline suspension story on page 42, for instance), but not only did I want to run lever arm shocks to continue the vintage theme, I’d also been hoarding a swap meet–sourced set for over a decade that I wanted to use on just such a project. They’re not early Ford Houdaille-type shocks; in fact, I’m not sure what they’re from. They’re Armstrong units, and by the shape of the arms on the front pair, they’re from an Austin Healey Sprite or Ford Anglia, but the rears, with their curved arms, are a complete mystery to me. I was pleasantly surprised, however, while attempting to identify them with the help of Google, that they have two valves, one for compression damping and one for rebound damping, and are easily adjustable. So nothing’s new . . .  This pair would have worked...  This pair would have worked if I could pass the tie-rod end through from above, but it was tapered from the underside, meaning the tie rod and wishbones wanted to occupy the same space.  This 1 3/4-inch dropped pair,...  This 1 3/4-inch dropped pair, intended for ’28-34 Fords, had the taper reamed from both below and above, meaning I could mount the tie rod over the top of the wishbones and springs.  For reasons I’ll explain,...  For reasons I’ll explain, I elected to make my own tie rod. First, I measured the distance between the wheels, both at the front (shown), and at the back of the rim, to ensure they were parallel. I then measured between the eyes of the steering arms, to give me the total length of my tie rod.  Speedway Motors sells tie...  Speedway Motors sells tie rods of various lengths, but they use a jam nut to secure the tie-rod ends. I wanted to use the stock Ford clamps and slotted ends on the tie rod for a period look. Whenever I see tie rods, or badly cobbled together rods like this one at swap meets, I always buy them, as the ends are reusable. With the tie-rod ends in place on the steering arms, I could determine how much of the end of each rod I wanted to use, and subtract these lengths from the overall length I determined in the previous step.  I ended up requiring a 39-inch...  I ended up requiring a 39-inch length of 7/8-inch DOM (seamless) tubing, which I drilled at each end in order to plug-weld to an internal sleeve. I also chamfered the ends for better weld penetration.  With the DOM tubing on the...  With the DOM tubing on the left, and a short length of an old tie rod on the right, you can see the internal sleeve inside each piece. Remember to use one left-handed and one right-hand threaded end from old tie rods, to facilitate adjusting the toe-in/toe-out during alignment.  I MIG-welded the plug welds,...  I MIG-welded the plug welds, and tacked the actual joint, which I’ll TIG-weld at a later date. My tie rod now appears old, with the clamps at each end. The slots that allow the threads to be clamped are on the underside.  My tried-and-tested method...  My tried-and-tested method of joining two lengths of tubing of the same diameter is to clamp them vertically and horizontally to a length of angle iron to align them while welding. Ensure the slots on each end piece of tubing are aligned.  With the cross steering sorted,...  With the cross steering sorted, I moved to the business of actually getting the wheels to turn. These tubular steering arms (which I may or may not end up using, depending on the steering ratio) are available from a number of sources. That’s an old tie rod connected to it, used as a drag link for illustration purposes.  The drag link is almost perfectly...  The drag link is almost perfectly positioned directly above the radius rod, supported here at its rear end by a jackstand in lieu of a steering box.  The pitman arm on the box...  The pitman arm on the box should be positioned directly above the rear pivot point of the radius rod to eliminate any bumpsteer, illustrated by the set square.  With the steering completed,...  With the steering completed, except for the actual steering box, which I have yet to source, I moved onto mounting the shock absorbers. Of note here, I could have used any of the steering arms discussed earlier that bolt to the spindle, if I’d run the tie rod across in front of the axle. I didn’t want to do that, however, as it always makes me nervous of what may happen if someone backs into your car, or you drive into something, and bend the tie rod.  My plan from the outset had...  My plan from the outset had been to mount the lever arm shock absorbers using the same bolt that locates the rear of the Posies quarter-elliptical springs. However, during assembly it became obvious that this provided insufficient clearance between the radius rods and the shock where the arm pivots. I elected to make brackets to weld to the spring housings and raise the shocks by a couple of inches.  The Lincoln Electric 375 plasma...  The Lincoln Electric 375 plasma cutter at our Tech Center made light work of cutting the 1/4-inch plate from which I made the brackets.  With the brackets cut out,...  With the brackets cut out, and the edges dressed they were held in place using 90-degree magnets, and then tack-welded. Final welding will wait until the chassis nears completion.  The shock absorbers were bolted...  The shock absorbers were bolted in place, and a set square used to determine the amount the links needed to be extended to mount underneath the wishbones, with the arms horizontal. These shocks have a lot of travel; way more than they’ll need in this application, but I still checked they wouldn’t bottom out in use.  Once again, angle iron was...  Once again, angle iron was used to hold the links while I TIG-welded a 2 1/4-inch length of tubing in place. I sandblasted the links first, taking care to tape up the ends.  I welded short sections at...  I welded short sections at a time and let them cool in between so as to not heat up the rubber in the end housings.  With the links lengthened,...  With the links lengthened, I just needed a way to attach them to the wishbones.  As the links had tapered connectors,...  As the links had tapered connectors, much like a tie-rod end, I fabricated a couple of brackets from 1/2-inch mild steel, thick enough to accept a taper. I always make pairs of brackets together like this, so they’re the same shape. Shame the plasma cutter wasn’t capable of cutting 1/2-inch material; I had to fab these using an angle grinder and file.  After drilling a 1/2-inch...  After drilling a 1/2-inch hole, I used a taper reamer from Speedway Motors to ream the taper. The tape is my high-tech depth gauge!  Voíla! Lever arm shock absorbers...  Voíla! Lever arm shock absorbers mounted to the split wishbones. You can also see here how I had to cut and bend the arms slightly (arrow), as originally they pointed out toward the front wheels. They now both point straight ahead, and align with the wishbones, not to mention look way nicer. All welds are tacks for now.  I mounted the second pair...  I mounted the second pair of lever arm shock absorbers at the rear of the chassis, but first fabricated a pair of these plates from 1/2-inch mild steel (yes, again with a cutting wheel in a grinder!), then drilled and tapped them to mount the shock body.  This pair of shocks had these...  This pair of shocks had these crazy curved arms that I figured would look neat going over the axle, but I didn’t want them protruding too far above the chassis (taking into account the arm will rise in operation) as I’ll be mounting my gas tank here. The mounting plate solved three problems: It was thick enough to drill and tap, meaning the bolts wouldn’t have to run into the chassis at all; I could mount it at an angle so the arm of the shock was perpendicular to the axlehousing; and it served as a reinforcing plate for the joint where I Z’d the frame.  Another pair of brackets,...  Another pair of brackets, similar to those welded to the wishbones up front, mount the shocks to the rearend.  The finished frontend. I wanted...  The finished frontend. I wanted a vintage-appearing suspension system, and I’m pleased with the results. Next, tires, and I’ll have a rolling chassis!
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