I Wanna Save Money DIY Car Tracking Check

steveo3002

mikey72 wrote: »

I did mine with a piece of hardboard and a 2 x 1.
I made a pair of little pointers, and attached one to the end of the wood, passed it under the car, and alligned it with one of the grooves around the outside(ish) edge of the tread. (tread has rings as well as zig zag patterns on it). I then attached the second pointer, aligned with the same tread ring on the other side. Checked the back and front of the tyre, it was out by about 8mm. Worked it out that was about 1.5 degrees, and wound it in to nearly 0, (toe in should be between 0 to 0.5 degree).
Roll the car back and forward after adjustment.
Tyres have been perfect since.
Edit can't remember the exact numbers, may even have been 18mm out, 1 degree is around 5 to 10mm difference front to back of the tyre on my car.

does the pointer need to be at the midway point up the tyre ...or will anywhere do as long as you use the same spot

mikey72

As far up to the centre is better, to maximise the angle, but so long as it is the same front to back to allow for camber it's ok.

steveo3002

right..just trying to picture what you made , my wheel arches are fairly tight

so its a long stick , with what at the ends ? im thinking plywood triangle then a pointer screw

i was going to try the string method but what you say sounds easier ..and mine is sposed to be paralel so no worrys working out degrees

mikey72

Yes, I used two triangles, fixed the first one and lined it up with the outside edge of a tyre groove, (perfectly round one), and fixed the other one (with a flatter "peak") then marked the same groove on the opposite tyre on the triangle, swooped the homemade rig to the front, remarked, and measured the difference in the two marks, made my adjustments then repeated. It was fairly simple after the first adjustment, just count the number of turns to the difference in the mm. I could also adjust both sides, and get the wheel straight.
I could also roll the car to relieve the stress after adjustment, then check again.

steveo3002

right i'll have a look then

i do have some some threaded rod ...maybe i could drill the wood to accpet it and make the other ends into pointers

cyclonebri1

mikey72 wrote: »

Why the edge of the rim?
I measure the distance across the two points so I can work out the angle I need, converted to mm.
Tyres are easier to get to, and add 8 to 10 inches extra into the calculation, so improves accuracy.
They are uniform all the way round, (or there is another problem anyway), and I roll the car to let the adjustment settle as well, so if they are distorted it'll show up.

Because if the figure is given as measurement in mm's it is intended to be measued at the wheel rim, of course this all goes out of the window if bigger wheels are fitted. For the same reason the measurement must be taken at the centre of the wheel, which you obviously know is still quite easy. Tyres aren't made as accurately as wheel rims and as you point out they are likely to other damage, bulges etc or distortion where a car has been sat on it's tyres without moving for a long period of time. It's also a more accurate feel with the comparator touching onto metal rather than rubber.
Not saying your what you do is wildly out but I was taught the method I use in motor sport circles.
I also simply use a woodscrew with a flattened end as the pointer, simply screwed in and out to make corrections, these screws are simply marked out at centre height, so you can have several positions to suit different cars, ;)

epninety

I've always used a few long bits of timber, but then I only ever set the tracking angle.
A few years ago I needed to check the caster angle, so I needed to sweep the steering over the full range and measure it.
I mounted two long bolts through a cheap spirit level, and the correct distance apart to hit the wheel rim. then I mounted a cheap ebay gunsight laser (just glued it on with araldite).

I park about 1m from the wall and mark the laser position from each front wheel. Then move the car back a couple of metres and mark again. Tracking angle is easy to calculate from the change in spot-spot distance and the change in car-wall distance.

Total cost was probably less than £20.
Of course, you need to get the front wheels straight before you start, but you can use the laser on the rear wheels to get some reference marks.

I did this about 5 years ago, so sorry if I forgot a step, or got my details mixed, but with a bit of thought it works very well.

jack_of_all

Im making my own version of the trackace, Ive ordered a better gun sight laser off ebay as my laser pen is dieing on me today, But i did test my gauge first several times today, Ive bolted a plactic mirror to a bar (will change to glass later)and made some props from flat bar welded with a Y at the end, it only works of the tyre wall for now but it is really accurate this method. Haven't got a proper target just a zero centre line for now, then I marked on the target my result. Check it forward and backwards on the car and it gave me the exact same result every time, just opposite. ie my toe out wheels show exactly the same but toe in if checked in reverse. The same as turning a spirit level on a wall to check if the level is accurate. Checked the opposite edges of the coffee table in the room and it showed bang on parralell every time, half a dozen neighbours are now waitng for my laser sight to come off ebay so I can check their cars too.

mikey72

cyclonebri1 wrote: »

Because if the figure is given as measurement in mm's it is intended to be measued at the wheel rim, of course this all goes out of the window if bigger wheels are fitted. For the same reason the measurement must be taken at the centre of the wheel, which you obviously know is still quite easy. Tyres aren't made as accurately as wheel rims and as you point out they are likely to other damage, bulges etc or distortion where a car has been sat on it's tyres without moving for a long period of time. It's also a more accurate feel with the comparator touching onto metal rather than rubber.
Not saying your what you do is wildly out but I was taught the method I use in motor sport circles.
I also simply use a woodscrew with a flattened end as the pointer, simply screwed in and out to make corrections, these screws are simply marked out at centre height, so you can have several positions to suit different cars, ;)

If you can do the maths, the tyre method is more accurate, as it's over a larger distance, takes allowance if you're not on the centre line of the wheel, and takes the tyres you're running on into the equation as well.

cyclonebri1

mikey72 wrote: »

If you can do the maths, the tyre method is more accurate, as it's over a larger distance, takes allowance if you're not on the centre line of the wheel, and takes the tyres you're running on into the equation as well.

Not if you accept tyre variances?

You do it your way Mikey, I'll do it mine, we will both save money,;)