Using a ford 9 narrowing jig is fairly much the only way to ensure your axle ends stay straight when you're shortening the housing for that will big-tire look. In the event that you've ever attempted to weld a rear-end housing without some sort of internal alignment tool, you probably already know how quickly items can go sideways—literally. If you apply that will much heat in order to a piece of steel tubing, it really wants to pull and warp. Without a solid jig maintaining everything in the direct line, your axle assemblies will bind, your own bearings will wear out in a week, and you'll be left with a very costly piece of scrap metal.
The Ford 9-inch is the full of the pull strip and the particular off-road world with regard to a reason. It's tough, parts are usually everywhere, and it's incredibly modular. Yet because it's a popular choice, people often believe they can simply chop the ends off with a Sawzall, weld upon some new casing ends, and call it a time. I've seen it happen, and this usually ends along with a lot of swearing. A correct narrowing jig isn't just a high-class; it's the base of the entire task.
Why the Alignment Bar Matters A lot more than the Welder
Most guys get really focused on their welding settings, but the true magic happens with the alignment club. A ford 9 narrowing jig usually consists of a long, precision-ground steel bar and a set associated with "pucks" or bushing. These pucks are usually designed to suit perfectly into the carrier bearing bores of the center area and the inner bore of your new casing ends.
Whenever you slide that will bar through the whole assembly, this forces the centerline of the housing ends to fit the centerline of the differential. In case those two points aren't perfectly concentric, your axles aren't going to end up being happy. Even a fraction of a degree of misalignment can cause serious vibration or even snapped axle shafts under load. It's one of individuals things where "close enough" simply isn't sufficient.
Setting Up the Jig for Success
Before you even consider grabbing the welder, you've got to get the casing prepped. You'll begin by stripping the particular housing down to the bare pipes. What this means is cutting away the old ends and removing any kind of old suspension brackets that might become in the way. Once you've got it right down to the particular basics, you'll bolt your "dummy" third member or the specific alignment blocks that include your jig in to the center section.
The attractiveness of the Ford 9-inch design is that the third member falls out. This helps it be easier to obtain the jig club through the middle. You'll place your own alignment pucks in which the carrier bearings generally sit. This determines your "true center. " Then, you slide the lengthy bar through those pucks. It need to glide through with a bit of resistance yet shouldn't require a sledgehammer to advance.
Cleaning the Areas
I can't stress this good enough: clean everything. Any bit of grit or old gear oil inside the tubes can mess with how the particular pucks sit. In the event that a puck rests cockeyed due to an item of slag, your whole alignment is away the window. Spend the additional twenty mins using a degreaser plus a wire brush. It's boring work, but it's exactly what separates a professional-grade build from a compromise job.
Computing and Cutting
When you're making use of a ford 9 narrowing jig , your measurements need in order to be just right. You're usually working toward a specific "wheel-to-wheel" width. Remember in order to factor in the width from the brake hat or drum plus the offset associated with the housing finishes themselves. Most people believe it is easiest in order to measure from the center from the pinion or the center of the casing to be able to the finishes. Once you've designated your cut lines, make use of a pipe cutter machine or perhaps a very stable hand with a band saw.
The Welded Dance
Once the bar is within place and the particular ends are slid onto the pipes, you're ready to weld. But don't just start lounging beads like you're building a truck frame. The high temperature will be your enemy here. Despite the jig bar holding almost everything in place, the pull of a cooling welds is incredibly solid.
The best way to do this would be to "clock" your welds. Start with four heavy tacks at the 12, 6, three or more, and 9 o'clock positions. After that will, move in little sections. Weld an inch on a single side, then move to the alternative part of the casing. This keeps heat localized and prevents the tube from bowing.
Leaving the Jig in Place
One mistake I see on a regular basis is people pulling the ford 9 narrowing jig out simply because soon as they're done welding. Don't do that. A person need to let that housing cool down completely—back to space temperature—with the pub still inside. Steel shrinks as this cools. If you pull the bar while the metal is still glowing, the cooling procedure can pull the housing ends away of alignment, and you won't actually realize it until you try to glide your axles in later.
DIY vs. Buying a Professional Jig
If you're only doing one axle in your lifestyle, you could be tempted in order to try and create your own jig out of some hardware shop threaded rod. My advice? Don't. Threaded rod has a lot of flex and isn't ground to the tight enough patience. You can often find used kits online, you can also even rent them from a few specialty tool shops.
When you plan upon doing a several of these, buying a dedicated package is a solid investment. A great kit include pucks for different casing ends (like Big Ford, Small Ford, or even GM ends if you're feeling adventurous). Getting a precision-ground one. 5-inch or 2-inch bar provides you with the particular peace of thoughts that your rear finish is actually directly. It's the kind of tool that will pays for alone in avoided head aches.
Common Stumbling blocks to Watch For
Even along with a great ford 9 narrowing jig , things can proceed wrong if you're not paying interest. One of the particular biggest issues will be "bar sag. " If your alignment bar is too thin or as well long, it can actually sag slightly in the middle as a result of to its own weight. High-end lures use thicker pubs to minimize this particular. If you're worried about it, try out to support the particular ends of the bar so there's no unnecessary leveraging pulling on your own alignment pucks.
Another thing to view for is the particular "squish" of the particular housing ends. Whenever you slide the particular housing end onto the tube, it must be a snug suit. If there's a lot of play, the jig will center the final, but you'll possess a massive gap to fill with welds. This extra weld volume means even more heat, which means more potential regarding warping. Try to get your tube size and the inner diameter of the housing ends simply because close as is possible prior to you start.
The Payoff: Soft Rotation
The particular first time a person slide an axle into a recently narrowed housing plus it clicks into the splines along with zero resistance, you'll understand why that will ford 9 narrowing jig has been worth the work. There's a certain "thunk" when an axle seats perfectly to the carrier that a person just won't obtain if the housing is tweaked.
A straight housing doesn't simply make assembly easier; it saves your gear. Your expensive auto aftermarket axles won't end up being under constant stress, your bearings won't get hot, as well as your gear pattern will remain consistent. In the world of high-performance cars, the back end is usually overlooked until it fails. Taking the time to use the correct tools during the narrowing process guarantees that the rear end is the particular last thing you need to worry about upon race day.
It's one associated with those projects that will feels intimidating the 1st time you do it, but once you have the jig in your hands, the logic of it all steps into place. It's all about developing a straight line and keeping it that way until the metallic stops moving. Do that, and you'll have a rear end that can handle no matter what horsepower you decide to throw from it.