Home Made Toe Gage How-to
 

Hi all! There seems to be some interest in changing alignment settings for better mpg, so I thought I'd show how I made my own toe gage out of common hardware store materials.

The idea behind this gage is to use something to measure the distance between the front edge of the rims, then compare it to the distance between the rear edge of the rims. There's really no need to measure the actual distance since this tool allows me to see and measure the difference. This gage should be used on a flat, level surface. Since this gage can't do a 4 wheel alignment it's best used only on the front wheels. If you mess up the alignment on the rear wheels your car could end up going down the road slightly sideways.

The first pic (see pic 1) shows the toe gage sitting on my kitchen floor.

Materials: the center portion is made with 1/2" x 3' angle iron (note, my car is about 67" wide measured to the outsides of each rim. Check your car. If it's much wider, use longer materials. Smaller cars won't have a problem using these materials), the verticle endpiece is 3/8" x 3' round bar, the other side (pic 2) is a threaded rod 3/8" x 3' with a matching turnbuckle on the end for fine adjustments, and a quantity of 6 U shaped clamp things 3/4" ID (silver parts in the pics). These parts cost about $18 from my local hardware store.

To build it, start by measuring the distance from the ground to the center of your wheels. The gage needs to touch the front/rearmost portion of the rim. Notice there's a curve in the vertical portion to clear the bulge in the tire sidewall. Start with the round bar and bend near the ends first, do the inner bends last. I used a 30 degree bend at 2" in from the end, a 5 degree bend at 6", and an 85 degree bend centered at 22" in( or whatever works for your wheel size), use a gentle radius. The last bend forms the foot so the gage doesn't fall over, so it's done 90 degrees off axis in relation to the first set of bends (see pic 1) Use a 90 degree bend 6" from the other end. 3/8" rod is easy to bend so you can correct it if needed.

The other endpiece is made nearly the same way, except the turnbuckle needs to be horizontal, so use a 85 degree first bend at 2", then continue with a 10 degree bend at 6", then a 85 degree bend at 22"( or whatever fits your car). If the turnbuckle is the right size it will spin freely on the threaded rod. This is bad for accuracy, we want it to turn with light resistance so it doesn't spin while moving the gage. I tightened it by slightly crushing the turnbuckle with vicegrips. I also thought about gumming up the threads with rubber cement. I'm sure there are other ways of accomplishing the same results.

Assemble the parts using 2 U clamps at each side. The other two U clamps are used as feet so the gage rests on the ground the same way each time. Since this is a DIY project feel free to add/delete features to suit your needs.

To use it, start by sliding the gage under the car and set the end pointers on the frontmost part of each rim. (see pics 3 and 4) If the gage touches a balance weight, roll the car forward or back so the weight isn't in the way. The first time you use it you'll probably need to adjust the U clamps to set the distance between the rims. Once it's close, use the turnbuckle so both pointers on the gage almost touch the rims. I like to see the slightest gap, less than 1mm between gage and rim. Check to make sure there is no tension in the gage, and that it's resting on the ground with nothing else touching or pushing on it since this could throw off the readings. Once you have the gage in the correct position with the pointers almost touching the rims, remove it from in front of the rims. This isn't as easy as it sounds since most tires bulge at the sidewall. If you just pull the gage outward you could bend it and throw off the reading. Instead, slide the gage so the pointer on one side is off the outermost edge and fits into a recess slightly inboard. That will give you some slack so you can pull the other side away from the tire. Yes, you'll be doing plenty of walking from one side to the other while doing the alignment.

Place the gage in a similar position on the back edge of the wheels. Again, use care when positioning the gage so you don't bend it and ruin the reading. Walk the gage into position taking advantage of any recesses in the rims. Compare the distance between the pointers to see if the back edge of the rims are closer or farther away. If the backside is wider, you have toe in. If the backside is narrower, you have toe out. Measure the difference and adjust the tie rods to compensate. Re-check the measurements after any adjustments. Any tool is only as good as the user, so take several readings before making any adjustments. Check that all readings are the same each time, if not, something isn't right and shouldn't be trusted for accurate alignments.

OK I don't know what happened to the first pic, but it didn't show up in the original post, so here's pic 1.

I adjusted the toe in on all 4 wheels of my Swift using a 9' long straight edge made from steel U channel. Just park on a level surface, set the straight edge up on a cinder block along side the door so it lines up with the center of the wheels front and back, then check the distance between the straight edge and the front and back of each rim. Quick and easy with nothing to fabricate.

Q

Are you talking about changing the alignment settings from what a shop would do, or are you just outlining a method for people to do alignments themselves. In other words, does the alignment shop not align the vehicle for optimal mpg?

they put it to factory specs, so whatever the car maufacturer decides is what they set it to. my dad and i made one and its really accurate because we set my trucks alignment with it and then drove straight to an alignment shop (we had to redo the casstor/camber and no way to check that at home) and when it was done and we got the report sheet about how much they adjusted it, it was only off by less than 1/8 inch (accuacy between thier laser alighment tool and our homemade one)

As is the case with recommended tire inflation pressures, the manufacturers' specs don't reflect the optimum for FE. Well, except for maybe in extreme cases like the Insight.

Okay, but with high tire inflation pressure, there's a trade-off -- not as comfortable or cushy a ride, perhaps decreased performance, etc. So the factory has other priorities in mind when specifying inflation pressure.

So I guess I'm asking how alignment specs could be altered to affect various aspects of performance. If the factory/alignment shop doesn't set the specs for ideal efficiency (i.e., lowest rolling resistance), then what is optimized? stability? traction? even tire wear?

Mmm-hmm. Like tire pressure, it's a balancing act. I'm guessing that they balance stability and tire wear most closely.

More toe-in = more stable = higher tire wear = lower FE

more negative camber (I think) = better handling = less stability = more tire wear

So they balance all of that to get what they think people want.

Yes, that's a quick and easy way to do it. Your method wouldn't work on my car since the front and rear wheels are not the same distance apart. The front wheels are .8" farther apart than the rear, so it's not square.

I've also added a touch of negative camber to the front wheels to make it corner better, which works nicely. The front end doesn't scrub as much when I take corners near the limit. The tradeoff is that it tends to follow truck ruts and grooves a little more intently now. Raising my tire pressure also increased this tendency. Has anyone else noticed this effect with high tire pressure?

Yes. Due to studded tires use the roads here have deep ruts. Both my Toyota pickup and my Swift tend to follow the ruts pretty badly with high tire pressure.

Q

Yeah, my car is quite a handful in a crosswind with its tires at the current 38 psi vs the recommended 32. The airdam has fixed 90% of that tendency, though.

Hmm... I have an idea :D

Here's a method I worked out that seems to work pretty well. I've tested other's methods and have made up a couple different methods myself...but am always looking for improvements.

"Actually, on FWD, the tendency on hard acceleration is to toe in. RWD vehicles want to toe out on hard acceleration and high speed cruising. FWD will tend to go to neutral on high speed cruising. FWD is best set dead ahead."

Is this correct????

Do know that toe is set at a certain place to offset the expected forces at work as you drive. In other words...with a rear wheel drive vehicle...you usually use some toe-in to negate the effect of the front wheels being dragged back some by contact with the road at cruise...and end up with zero toe. With FWD...the drive wheels are pulled forward some by being powered at cruise...negating this effect...thus a zero setting? Some cars specs are there to improve driveability..not for max mpg?



Wheel alignment 101:

https://www.familycar.com/alignment.htm


How to do it:

* Before starting: You need to be sure that your wheels do not have side to side runout…or your attempts to set the toe-in will likely be off. You can check this by rotating the front wheels and watching closely for any side to side movement…or you could use a dial indicator.

* If your toe specs are given in degrees…you will have to translate this into inches at the tread. You probably wouldn’t go wrong just shooting for zero toe or a slight toe-in with most cars.


* right click to see?

https://www.nonags.org/members/nijqk/level-laser-med.jpg


https://www.nonags.org/members/nijqk/...laser-full.jpg


This method uses a level as a straight edge and uses a square tube taped to this level to take a more accurate reading from the wheel instead of from the tire.

The laser is used to translate the reading *accurately* down to a 2x6 laying on the ground.


How to do it:

* drive the vehicle straight forward on a level gravel surface and stop it gradually.

* I place a 2x6 behind the front wheels positioned so the hanging laser will project a dot on its surface at both ends.

* I then place a mark (MARK 1) on one end of the 2x6. Then hold the level and laser setup SOLIDLY** on the wheel at hub height...using the bubble in the level to level it out. Waiting for the laser to quit moving...I align the mark on the 2x6 with the laser dot.

** the square tube needs to be uniform and straight...it needs to be placed NOT on the rims edge (most easily bent?)...but on a flat area of the wheel if possible. Each time the tube is placed on a wheel...it needs to be placed in the same way.

* Without moving the 2x6...I then move the level and laser setup to the opposite wheel and make a new mark (MARK 2).

* Then the 2x6 is moved to a similar position in front of the tire. The level and laser setup is then held on the same wheel and (MARK 2) is aligned with the laser dot.

* Without moving the 2x6...the level and laser setup is moved to the opposite wheel and MARK 3 is made where the dot is projected on the 2x6.

* Then using a dial caliper...the distance from MARK 1 to MARK 3 is carefully measured...but ONLY along the LENGTH of the 2x6...ignoring any offset side to side on the 2x6. This can be done accurately by using a carpenters square to scribe a line at each mark.

* The difference between MARK 1 and MARK 3 is your toe in or toe out.

NOTE: This is only the case IF you have the laser set up to hang down right at the tread of the tire. If it is out further than this your reading will be exaggerated some.

This method is accurate only if the laser is hung from the level in such as way that it hangs the "same" when the laser is flipped over for use on the other wheel...pivots must be free.

Marks must be made very carefully. Don't try this on a windy day.

...

Adjusting the toe:

* It’s best to have hit BOTH tie rod adjusting threads with penetrant BEFORE starting this whole process.

* The process of dialing in to the correct toe-in can be frustrating IF you don’t make very small changes relative to your previous setting. Probably best to move the adjuster by no more than 1/8 to 1/4 turn at a time…unless your toe-in is way off. Do not try to guess or set it relative to the rear tires.

Centering the steering wheel:

The steering wheel needs to be reasonably close to center in order for your turn signals to be able to cancel correctly.

* IF your steering wheel is off to one side when driving straight down a road, then you would want to try and correct for this when you adjust the toe. You do this by turning one adjuster in or out on one side…which side…depending on where the steering wheel is driving straight ahead and whether the tie rod is in front or back of the axles.


Cautions: An inexpensive laser might not be very rugged…so you’d want to treat it carefully.

Obviously…DON’T look into the laser light…and don’t point it at people.

The main points to consider in order to do it right are:

Be consistent each time you place the laser and tube on a wheel…mark exactly in the center of the laser spot…measure carefully between marks (1) and (3).

If you have hit a curb or had an accident…you’ll likely need a professional alignment…since there are many other settings involved in a complete front alignment.

Or use a plumb bob
 

skewbie, that is a good idea. have to do in in a garage on level surface in a windless area tho...

The problem with tape measures and bars is that you are only measuring maybe 1/16" or less...too easy to have too much flex in a bar or inaccuracies when you measure...not to mention the chassis being in the way.

I tried the cheapo JCWhitney bar with springs...real flimsy...but the sprung reading lever or whatever might work.

The right kind of plumb bob would work as well as a laser...if you can get the point of it near enough to the floor to make an accurate mark?

You can find a pen type laser pointer for $10...my level laser cost $12.

My neighbors think I'm crazy (they might be right) when they see me out in the driveway testing various alignment methods...over and over and over. But it still beats setting up an appointment for an alignment...by the time I factor in the gas cost to get there...time wasted waiting...charge for the job...I can afford to diddle around in the driveway some.

I seem to notice the same thing with alignments as with dentistry...if they figure out that you can't DIY...they charge a lot.

"k.i.s.s."
I agree.

skewbe, zugy, how longs does it take to check the alignment with your methods?

15 minutes? Finally have a method I can live with...I should post the last one...or maybe I did.

Problem is....how often do I do an alignment? So I need to write instructions for myself so I remember how. :rolleyes:

7 minutes: kick crap out of the way in the garage and sweep a little, roll car in.

2 minutes: futs around looking for an appropriate sized block and pencil

16 minutes: futs around looking for the plumb bob you just bought

5 minutes: drop the marks to the floor (might as well do the rears too)

1 minute: move the car out of the way

10 minutes: measure distances between every mark carefully. Interpolate between the tape marks, that's your domain there. sketch the lines and associated lengths on a piece of paper. Helper helps with tape measure.

3 minutes: Dig up your old trig book, look up the cosine law.

5 minutes: figure out all the angles

10 minutes: Scratch your head for a while because the angles don't add up. wait for reducto-ad-absurdum to resurface in your memory.

5 minutes: figure out all the angles the other way.

3 seconds: compare the angles of the front wheels for toe in.

Total time: 64:03 minutes:seconds

Note, I'm sure there are better calculators and/or web sites that will do the trig for you.

Dam, that's a lot of time!
It takes me about 15 minutes to check alignment, more if I adjust it. Add ten minutes to re-check alignment each time I make a change.

I have this page saved since I can't remember trig. https://www.regentsprep.org/regents/M...rig/LtrigA.htm
HTH