At home Alignment?

[deadcarny]

Any way to get the alignment "kinda close" as far as the caster and camber? I installed new bushings all over up front and new springs and shocks. The car is still a long way from street worthy, but I want to get the alignment close so I do not wear out the tires too bad moving it around or if I drive it down the road behind the house...LOL...
I can visually look at the car and see the Camber is off pretty far. I also have a ton of alignment shims. Any ideas?

[TLWiltman]

Check out www.stockcarproducts.com under accessories. Or you could probably do a search for Longacre Racing Products on the web. They make a bunch of products for doing an alignment on any patch of level ground.

[KAA]

I use one of these:

http://www.polepositionrp.com/CHASSI...AUGES.htm#9100

Seems to work fine.

[deadcarny]

I am looking for something cheaper. I think I am just going to machine some wedges on specific angles and use a bubble lever against them. cost=free..... I am not sure if it will work, but I guess I will find out.

[chicane67]

Build string guages and use rules and/or a dial calipers for your measurements.

You did say cheap right ??

[Jimmy Sean]

Read this, hope it helps. You will still need to know what alignment numbers you are after.

http://www.shallowsky.com/alignment.html

[Norm Peterson]

The most important word is PATIENCE.

Find a level (or at least flat) surface, inflate your tires to where you’ll be running them, and load the car approximately as it will be driven. If it isn’t perfectly level, you can either shim the low wheel spots up to level or correct your measured angles once you know how far out it is. And at least simulate the driver’s weight with something like barbell plates.

For a number of years, all I needed was a carpenter's 12" combination square with a bubble level in the handle, a small scale that measured in 0.01" increments (it was just something I had; 1/32" graduation is probably sufficient for most work). Plus 4 jackstands, two lengths of black thread, a plumb bob (or something that'll work like one; a church key on a thread will do in a pinch), a steel tape or two, and a calculator that has trig functions.

Camber is measured by placing one end of the C-square against the wheel rim, moving the other end until there's "zero bubble" in the level, and measuring the gap at the other end. Since the wheel is somewhat larger than the 12” C-square is long, you'll be a few inches ahead of or behind the axle centerline. I normally took measurements at both locations as a check on my work. Be sure that the square is perpendicular to the pavement as seen in side view. Then a little math and use of either the arcsin or the arctan function (the difference is negligible at the magnitude of the angles you'll be working with) will give you the camber angle. Or, since it's close enough to 0.15* per 1/32" gap over the 12" length of the square's ruler, you can use that conversion for most work.

Eyes that now appreciate reading glasses for close work and a desire to simplify the math still further led me to fab up a caster-camber gauge that uses a dial indicator (around $30 plus the dial indicator) in place of the C-square. There is a pic link on the first page of this thread, and some full-size pics on the second page (warning to unaccelerated dial-up users about page 2 load time). Welding was held to an absolute minimum to avoid distortion, so it’ll never win any beauty contests.

Caster is most easily determined by taking camber readings with the front wheels turned right, then again with the wheels turned left the same amount, taking the algebraic difference and applying a factor. This factor depends on the steer angle you use. If you can get 30* steer out of the front wheels, this factor is 1.00. At 14.5* (a much easier angle to obtain), it's 2.00, and a 20* steer angle uses 1.46 as a factor (meaning that SmartCamber's 1.5 factor is pretty good, being less than 0.2* off in 6* caster, and the 1.5 factor actually comes up at 19.4* steer). There’s a discussion of the general solution here complete with exact formulae, but the factor ends up being pretty close to 0.5/[sin(steer angle)]. FYI, what I've been calling 'steer angle' is referred to in that SAE paper as toe; so don’t confuse the paper’s terminology with that other alignment setting.

Toe is measured from the strings, stretched over the jackstands and set to be parallel to the car centerline. If you're a little off, there won't be any problems with total toe, though if you were going to get into measuring rear toe and thrust angle they would be off slightly. Anyway, this setup requires some patience. Initially, set the strings to be the same distance off some equivalent left and right side chassis references. Working off the wheel centers will work if all you're concerned with is front toe but will involve more math and/or offsetting the strings unequally if your rear axle isn’t quite centered and you want to measure rear toe and thrust angle. Measure the distance between the strings with the plumb bob and the steel tape(s) in front of and behind the car. Adjust both strings equally until the distance between them is the same at both ends of the car.

Once the strings are parallel, you measure between the string and the wheel rim at the front and at the rear of each front wheel using the same little scale. Measure the distance between your measuring points on the wheel and you can now either calculate the toe as an angle or scale it up to the outside tire diameter to get a toe measurement in inches. That's toe per side, and may be either 'in' or 'out'. Total toe is the algebraic sum of these angles (or inches), considering toe-out to be of opposite sign to toe-in. I think the industry convention is + for toe-in expressed as an angle, BTW.

If your measurements are reasonably close to your desired settings, the sequence of adjusting things is caster, camber, and finally toe. If you're way off where you want to be, it's probably easiest if you roughly set camber, set caster, go back to camber, and then do toe. Then go back and check everything. This does get easier with a little practice.

There is a mathematical solution for setting caster and camber in one shot, though you need to know precisely where all the pivot point centers are in 3-D space relative to one another and how the adjustment moves them (likely at some skew angle). Sometime I may attempt a spreadsheet solution, but it's not a current priority. And you still need to go back and check.

Norm

[deadcarny]

Great info, Norm! I did a quickie set-up last night on my own before reading all this. Mine is not accurate at all, but I figured it might get me in the ballpark.

Here is what I did:
I took a small level and put it on the top of the tire (tires are BRAND NEW) to see how level the tires were. Once the tires were about level, then I put the level on a machined surface on the top of the spindle. The spindle with no shims was facing very far forward, so I shimmed the rear of the shaft out until the bubble just slightly went to the front (spindle facing back now). Then I checked camber again. I did this on both sides to get them close to even. Then I took my steel tape and some 2x4's to check the toe, which was already right at about 1/6th toe-in, so I left it. This should be good enough for me to move the car around and drive it out back to test the brakes when they are finally all finished (need to just bleed the rears today and add a proportioning valve later). I only had very thick shims to use, and ended up with 5 thick shims in the rear of the Right shaft and 3 in the front, and 3 in the rear of the Left and 1 in the front.