# Advice requested from those of you who have successfully checked camber at home - Page 2

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Re: Advice requested from those of you who have successfully checked camber at home
snipped-for-privacy@snyder.on.ca actually said:

This off-topic confusion is all my fault.

I should never have brought toe into this discussion because toe is easily
done at home when you have specs that are in linear dimensions such as
inches but not so easily understood when you have toe specs in angles.

Clearly I'm confused how to do the conversion.

Re: Advice requested from those of you who have successfully checked camber at home
On 12/9/2016 11:20 AM, John Harmon wrote:

Ya, I am to. But first let me say this, The first spec you posted,
0* 14' plus or minus 10', seems this isn't as critical as some posters
are making it.
For toe, it is still a trig problem, but the problem is defining,
side b (a reference point).

>  http://www.carbidedepot.com/formulas-trigright.asp

I wonder do the shops attach a laser and measure on a wall scale a
defined distance away?

I don't know this, is it a single adjustment that moves both wheels or
do you adjust both wheels separately? (makes a reference even more
important)
Sorry just thinking on the keypad.

You have a trig problem and a measurement problem.
The measurement problem is more difficult.

It is not be hard to convert the 14 minutes to inches using the wheel
diameter as one line.
The angle is how much more is the front of the wheel turned
in more than the rear of the wheel. I'll call the wheel 16"
from front to rear. (just realized this almost the same trig problem for
camber, just rotated 90*)

I'm using the trig calculator above, this time the orientation is correct.
Put the following numbers in, (side c) = 16, (angle A) = .233. The angle
is .233 because 14min/60min = .233.
Your answer is (side a) which is 0.065". So, you want the rear of a 16"
wheel stick out 0.065" more than the front.
Not real easy to measure, But, if you could extend the 16" to 12 ft
(192") with a laser pointer, then (side a) is 0.781".
The laser must be perfectly square with the wheel.
Just some thinking. Hope it makes some sense.
Mikek

Re: Advice requested from those of you who have successfully checked camber at home

The measurement problem is more difficult. "

I was wondering when someone was going to mention trig.

What he needs is something to act as a really huge caliper. Looking at the
bottom of most cars there is no centerline to be found.

Actually is you can be absolutely sure the car is on a level surface, somet
hing like a plum bob could work. Measruing it accurately is still a problem
, from the rim to a string ? And adjusting to minutes with only like 16" to
work with ? No thanks.

But the good news is that you don't need the  BMW alignment machine, they a
re not really brand specific. That means he does not have to go to the deal
er and pay three times what an independent would charge.

On older cars I did set the toe in a few times. There was enough clearance
to measure underneath wheel to wheel. Whaddya think the odds of that are he
re ? Did Slim leave town ? I never set caber or caster in the old backyard,
but usually you don't heave to, even after replacing ball joints. They hav
e to pretty far out of spec to affect it enough, really. Still, usually I w
ould just pay the damn forty bucks and have it aligned. Of course that fort
y bucks is now a hundred, but how much is a set of tires ? A nice set of Du
nlops or Michelins is worth the cost of an alignment, plus the car handles
better. Plus with really good tires it rides better and quieter.

But some people are penny wise and pound foolish.

Re: Advice requested from those of you who have successfully checked camber at home
On 12/9/2016 3:53 PM, snipped-for-privacy@gmail.com wrote:

You just haven't read all the posts, I have at least 3 maybe 4 posts
that mention trig and I posted a calculator, with the problem to solve.

I mentioned finding the reference is the hardest part.

Measuring it accurately is still a problem, from the rim to a string ?
And adjusting to minutes with only like 16" to work with ? No thanks.

I also mentioned if you could mount a laser square to the wheel, then
you could measure at 16ft on a wall and use 0.781" instead of 0.065".
I said 12ft in my post, that was wrong.

That means he does not have to go to the dealer and pay three times what
an independent would charge.

Whaddya think the odds of that are here ? Did Slim leave town ? I never
set camber or caster in the old backyard, but usually you don't have to,

even after replacing ball joints. They have to pretty far out of spec to
affect it enough, really. Still, usually I would just pay the damn forty

bucks and have it aligned. Of course that forty bucks is now a hundred,
but how much is a set of tires ? A nice set of Dunlops or Michelins

is worth the cost of an alignment, plus the car handles better. Plus
with really good tires it rides better and quieter.

And sometimes people are penny wise and also pound wise.
It really ads up over 30 years.
Mikek

Re: Advice requested from those of you who have successfully checked camber at home
amdx actually said:

Now that I've done some more research, I have a better handle on 'toe' so
I'm going to agree with you that getting toe precise to 2 minutes isn't all
that important, in all likelihood.

For *setting* toe, especially in the rear, it could easily be that 0 toe
(degrees or inches) would be just fine, or, maybe, to take up some
suspension slop, a "smidgeon" of toe (maybe 1/16th of an inch or less in
linear dimension no matter what the wheel/tire diameter).

This is to take up the slop in the suspension (perhaps slightly more in the
front if it's a typical RWD like all my vehicles are).

I'm still confused how to convert toe from degrees to inches, but luckily,
there are web sites that will do it for us.
https://robrobinette.com/ConvertToeInchesToDegrees.htm

Interesting you mention that, because the reason for the *far away* wall is
simply that the angle is small, right?

If you are talking about toe, I'm no expert, but the way I understand it is
that you lock the steering wheel in the center position first (which has
nothing, per se, to do with alignment but with esthetics) - and then - you
pick a side, and twist a tie-rod ever so slightly - which - depending on
the direction of twist, moves the front of the wheel in toward the
centerline of the vehicle - or outward.

So it's one wheel at a time, measured to the centerline.

Of course, you can assume all sorts of symmetries and do both wheels at the
same time, but conceptually I think of toe as a wheel-to-centerline thing,
to be done one at a time.

That's an interesting observation that the measurement problem is more
difficult, but I think only if we try to measure degrees of toe.

If we measure inches of toe, the measurement problem is conceptually
trivially simple.

I'm trying to find the triangle in the equation of toe in order to figure
out how to convert the distance measurement to an angle.

Here I just drew what is my first pass guess at where that triangle lies:

Is *this* the trigonometric angle everyone is talking about?

You make a good point here in that we really have a 3-dimensional X, Y, and
Z axis, each of which is rotated by 90 degrees (caster, camber, and toe).

Just to ask to get me more firmly grounded, is *this* the triangle everyone

Re: Advice requested from those of you who have successfully checked camber at home
snipped-for-privacy@snyder.on.ca posted for all of us...

+5 and high school math... He could go back to school and learn all this for
less bux than he wasted-not to mention our time.

Drive it to the BMW shop and tell them you want it set to the preferred
settings. Make certain all your bushings and arms and their esoterically
named crap is brand new because as it wears it will change. Don't hit any
curbs, potholes, driveways, obstructions of any sort, or drive it period.
Better get new springs too as they will sag and take everything out of the
trunk. If it's a convertible weld some stiffeners along the top. Have your
partner and you control their weight. Fill up with gas first. Get all
pebbles, stones and other safarcus out of the treads. Make certain the tire
pressure is within a 10/th of a pound. I am sure I am forgetting
something...

--
Tekkie

Re: Advice requested from those of you who have successfully checked camber at home

wrote:

I too am starting to wonder if this guy is nuts, or maybe just a
troll. There is some very simple math involved here.

Re: Advice requested from those of you who have successfully checked camber at home

could be both.

and some common sense.

Re: Advice requested from those of you who have successfully checked camber at home
Bill Vanek actually said:

Hi Bill,

If you can answer this question then it will show that you actually
understand what you call *simple math*.

Here is the question:
https://s23.postimg.org/ajrtf269n/10_total_toe_angles.gif

Summarized, that says: If total toe is the difference in toe between the
rear and front of the tire, and if the difference in angles between the
rear and the front of the tire are exactly the same (by definition, since
the angle of the wheel/tire combination to the centerline of the car is the
same no matter what size the wheel/tire combination is!), then how the heck
can total toe be specified in degrees?

Re: Advice requested from those of you who have successfully checked camber at home
On Sat, 10 Dec 2016 22:37:01 -0000 (UTC), John Harmon

I replied to your original question days ago, and you ignored that
repeatedly. Toe *is* an angle, but if you know the outside diameter of
the tire, it can also be spec'd in inches, or any other linear
measure. The conversion involves only the measure of sides of a
triangle, which is really basic math. This is my original reply:

Inches depends on the outside diameter of the tire:
https://robrobinette.com/ConvertToeDegreesToInches.htm

Minutes to degrees can be found here:
http://zonalandeducation.com/mmts/trigonometryRealms/degMinSec/degMinSec.htm

Regarding the needed accuracy, it depends on exactly what you are
trying to achieve. There is a wide range in camber that will not cause
any meaningful tire wear. Toe is much more critical, including for
overall feel at higher speeds, but you are also dealing with runout,
and there really isn't any good way to adjust for that at home.

The overall point is that even if you are off with the camber, the
tires are not going to be worn out all that much earlier, so close can
be good enough, especially if you bother with rotation. Toe is much
more important, and if you want that exactly right, pay someone to do
it right. You can get it close at home, but it's just luck if it's
exactly right.

You also have to keep in mind that a rear drive car's toe out will
increase with speed, and a front drive car will do the opposite. There
is plenty of slop in steering & suspension, and you will get varied
readings, especially if you are not using turntables. Sometimes trying
to save money is not such a good idea.

At the same time, finding someone to do the job right can be a
challenge, too. There's plenty of hacks out there.

If all you care about is getting things close enough that there won't
be ridiculously excessive tire wear, then have at it. But if you are
trying to get things just right, both for handling and tire wear
purposes, pay someone.

Re: Advice requested from those of you who have successfully checked camber at home
Bill Vanek actually said:

I had/have no problem with the trigonometry, since it's simple soh cah toa
stuff, these triangles.

My main problem is where was the triangle.

It seems to me that, if toe is specified in inches, then the triangle
should be specified at some known point off from the center of the wheel to
the centerline of the car.

If they specify toe at any other point than a known point off from the
center of the wheel, then they have to specify how far they are from that
known point for any inches-to-degrees conversion to apply.

Isn't that right?

I completely understand that measuring inches from the tire tread to the
centerline of the car and then using that as the "opposite" in the
trigonometric soh cah toa, will come up with the wrong angle which will be
more and more wrong the further the measurement is taken from the center
point of the wheel.

When they specify toe in inches, why don't they just specify it from the
rim of the wheel (instead of from the tread of the tires?)

I can convert with basic sohcahtoa trig but I need to visualize the
triangles first.

thread, which I can summarize as no basic home tool will get the accuracy
specified by BMW (which is 1 minute for camber).

However, you really don't *need* that accuracy (which is what you are
saying).

An inclinometer will get us to about 1/10th of a degree (six minutes) of
accuracy as stated on thisadvertising blurb:
http://www.sears.com/craftsman-10-in-digital-lasertrac-reg-level/p-00948292000P

A typical smartphone apparently uses either a gyro or a magnetic compass
and accelerometer, which can't get to the same accuracy (it seems) as an
inclinometer can (or so I'm told).

However, in the end, a "smidge" of negative camber (about a degree or so)
is probably in the accuracy range we really need, which a smartphone can
do.

Static toe is actually easier to measure and harder to measure than camber,
it seems.

It's easier because it's easy to measure distances and then convert those
distances to degrees using basic sohcahtoa trig.

It's harder because you can't easily measure degrees of toe with a typical
inclinometer level or smartphone gyro/compass/accelerometer because they're
based on gravity which is in a different plane for measuring camber angles
as it is for measuring toe angles.

BMW does not recommend ever rotating tires, but they don't care about tire
wear. The camber is only adjustable in the rear and it's pretty high (I
forget but it's at least 2 degrees negative camber for each rear wheel).
That wears out the inner edge like you can't believe.

Me? I'm ok with zero camber but that can't be obtained (the last alignment
proved that). But I think 1.5 or 1 degrees was what the guy was able to get
me.

So, for me, the camber setting would be to simply put it at the lowest it
will go (least negative) for the bimmer but for the toyota I have a wider
range (where only the front camber can be set because the toyota has a
solid rear axle so nothing is settable).

As for wear, it seem everything goes in this direction:
1. caster
2. camber
3. toe

In that caster is done first, then camber, and then toe, and in that wear
is least with caster and then more with camber and then even more with toe
(under typical settings).

It's just x y z planar stuff. :)

I have done my toe when I replaced tierod ends, pitman arms, and idler
arms, and then when I took the cars for alignment, the toe was spot on.

So I think toe is easy, compared to caster and camber.

I'm an old man who has never had a FWD car and I hope that I die before I
ever stoop that low.

So all my questions are for RWD vehicles.

The simple test is to set the alignment at home, and then take it to the
shop for double checking. Many shops offer free tests if nothing needs to
be changed;  but I would hesitate to take them up on that only because they
can always find something so I suspect that's just a gimmick.

Has anyone here ever gotten the "free test" actually for free if there was
nothing to change? Or do they always find "something"?

Never in my life (and I'm an old man) have I seen a mechanic install a tire
correctly (I use Tire Rack authorized installers), so I suspect it's the
same with alignment.

For example, I had to bring 500 pounds of my own weights to my last
alignment. The alignment guy *knew* how to do it right, he just knew that
most of this customers don't have a clue.

It's the same with the tire mounting shops. They *know* how to do it right,
but they also know most of their customers don't have a clue so they get
lazy.

I doubt a single car tire is installed correctly, by the book, on any car
taken to the typical tire shops (wheel works, goodyear, midas, etc.).

I think the summary is this simple.

A. Check the alignment at home for the things that can be adjusted.
For my Toyota, that's only caster, camber, and toe in the front, and for my
bimmer, that's only camber and toe on the rear and toe on the front.

B. Adjust if necessary (using a smart phone or inclinometer for camber, and
a tape measure for toe). I'm not sure how to do caster in the toyota since
I only just found out that the caster is adjustable on the toyota.

C. Take it to one of those "free if it's ok" shops, and see what they get
for measurements.

If I'm perfect, it's free (I assume); if it needs adjusting, then I learn
what can and can't be done.

Re: Advice requested from those of you who have successfully checked camber at home
On Sun, 11 Dec 2016 01:07:00 -0000 (UTC), John Harmon

The old standard was always about +- 1 degree, when you had no other
specs to go by. Enthusiast cars like the BMW have different needs for
handling purposes.

That's not uncommon.

That doesn't sound right. 2 degrees should not cause early wear, so
you really need to check the ride height. And recheck the camber.

Yes, caster will not cause wear.

That's not the reason for the order, but it's not important.

I hate to say this, but you can get pretty close just eyeballing toe
and camber. Especially with camber, if you can't see any substantial
lean, the camber is probably close enough that it won't cause tire
wear. In a pinch, it works for toe, too.

It's not necessarily a repeatable test, though. The one time you do
that, you might have gotten lucky.

They are expected to print out the readings, so it takes some effort
to lie. I'm sure they usually find something, but that's only because
cars do go out of alignment.

I'm pretty sure that none of the manufacturers expect techs to load a
car before alignment anymore. The specs take into account average
occupant weights.

And I doubt that it makes the least bit of difference.

You don't really learn that, except for each time you try it. You can
get very different results on future attempts.

Re: Advice requested from those of you who have successfully checked camber at home
Bill Vanek actually said:

I just looked that up for my two cars.

The Toyota spec for the front camber is -.6? to .9? which is exactly in the
range you suggested.

The BMW rear camber E39 I6 and 540 models with "standard," "low slung
sport" and "M-sport" suspensions spec is apparently -2 deg 10 minutes. The
tolerance varies among options: either +/- 20 minutes or +/- 25 minutes of
angle.

The M5 spec is -1 deg 50 minutes perhaps due to 275/35 section width tires
vs 225/55 for I6 cars.

For the caster on the toyota of 1.7 to 3.2 degrees, I am not yet sure how
to measure it for the Toyota but I won't have to bother for the bimmer

For the camber of -.6 to .9 degrees for the Toyota, I think I'll use a
magnetic base inclinometer such as the Husky 10-inch Home Depot electronic
level.

I think I'll just set the toe to 1/16th of an inch less in the front tread
(measured as close to centerline of the wheel as possible) than in the back
tread to centerline of the vehicle.

That will give me a total toe of 1/8th inch on the Toyota.
I'll use toe plates and a tape measure, I think.

True. But it would be free if I got lucky! :)

But if I align it first, it should be within spec, at least for what can be
aligned, which is, for the toyota, front caster, camber, and toe, and for
the bimmer, rear caster and toe and front toe.

The 500 pound loading on a bimmer is for a different purpose.
You are supposed to put 100 pounds on the driver seat, 100 pounds on the
passenger front seat, and 200 pounds evenly spaced on the rear bench and
100 pounds in the trunk.

That artificially "lowers" the car to a specific "ride height" which all
BMW alignment specs are to.

There is much discussion of why BMW uses that artificial ride height to
normalize all their specs, but it has absolutely nothing to do with the

I mostly agree with you that when the tire shop torques *all* lug nuts and
bolts to the same 100 foot pounds, it probably doesn't hurt anything. Nor
if they fill up all tires to the same 40 psi, again, it won't kill anyone
(even though BMW specifies different pressure for the front versus the
rear).

That they pry off the BBS hubcaps with a screwdriver just breaks the
plastic tabs. And that they don't remove all the old weights just makes
them put more on each time (and increases the chances of an imbalance from
a lost weight).

And that they don't mount the tire with the red or yellow dots to the valve
stem or match mounting mark just means they'll use more weight than
necessary.

That they don't even torque the bolts in a star pattern probably only makes
the wheel slightly crooked.

So, I agree with you that the fact that no tire is ever mounted correctly
isn't causing accidents left and right.

But it's still wrong.

Re: Advice requested from those of you who have successfully checked camber at home
On Sun, 11 Dec 2016 01:07:00 -0000 (UTC), John Harmon wrote:

Yes. That's why they specify toe directly as an angle. HTH. Cheers, -- tlvp
--
Avant de repondre, jeter la poubelle, SVP.

Re: Advice requested from those of you who have successfully checked camber at home
Tekkie? actually said:

The problem I have is confusion about where the triangles are for toe, and
it has absolutely nothing to do with high school math since the trig
involved is easy (soh, cah, toa) if we only knew where the triangles are.

For example, total toe is specified in *degrees* of all things.

Yet, total toe is simply the toe measured at the back of the wheel/tire
combination minus the toe measured at the front of the wheel/tire
combination, both of which are *linear* measurements.

Since toe angles are the same no matter what size the wheel/tire
combination, how can total toe be specified in degrees when it's measured
in inches?

Since the tire has the same angle the entire time, there is absolutely no
difference in angle between a toe measured at the front of a wheel/tire and
a toe measured at the back of that wheel/tire!

So, sure, I'm confused because total toe is specified in degrees.
But the confusion has nothing to do with high school trig.

Summarized, if total toe is the difference between toe at the rear of the
tire and toe at the front of the tire, yet, the angle of the wheel/tire
combination to the centerline of the vehicle is the *same* no matter how
large a wheel/tire combination is, then how the heck can total toe be
specified in degrees?

https://s23.postimg.org/ajrtf269n/10_total_toe_angles.gif

Re: Advice requested from those of you who have successfully checked camber at home
On Sat, 10 Dec 2016 22:34:02 -0000 (UTC), John Harmon wrote:

Silly, it's specified in degrees because it's measured in degrees. HTH.
--
Avant de repondre, jeter la poubelle, SVP.

Re: Advice requested from those of you who have successfully checked camber at home
On Thursday, December 8, 2016 at 3:12:14 PM UTC-5, John Harmon wrote:

You are well-and-truly an idiot!

The measuring device must be accurate to one one-hundredth of a degree, or
two decimal places. The measurement itself will be far less sensitive than
that, probably to a single degree, no more. But if I am staring (for instan
ce) at 90 degrees and want to get to 89.75 degrees - hence the need for tha
t level of accuracy.

Azimuth on the typical smart-phone (how accurate is it a measuring off the
vertical) is typically somewhere between 8 (at best) and 15 degrees - and t
hat only if it has a screen-orientation function. Many do not. And many mor
e have only a 90-degree function and only in one direction.

Put another way, the phone is smart enough not to even attempt the process.
The idiot owner who insists that it is possible - with the right app/softw
are - deserves exactly what he gets.

Minutes are a circular unit-of-measure. Not a linear unit. So, "inches" wil
l be measured at some point on a diameter as compared to another point alon
g that diameter using a fixed radius. If 'vertical' minutes, one endpoint o
f that radius will be the center of the earth. If other than vertical, the
determining endpoint will be something hopefully more nearby such as the ax
le or some specified point. And the diameter on which the distance is measu
red will be specified.

But, minutes do not convert to inches other than the chord defined by the s
tarting point and the end point of the measured distance along the total ar
c.

False premises lead to false conclusions. I am calling you an idiot as you
seem congenitally unable to understand the most basic geometry - previously
most basic physics - yet insist on some sort of false precision to draw ot
hers into your idiocy as an actual problem. It isn't. Otherwise, you are a
simple (very simple) troll. Yeah, I am responding - in the same way that ou
r grandkids enjoy Wack-A-Mole at the penny arcade. You will probably never
go away, but well-turned invective can be enjoyable, even if against a help
less target.

Peter Wieck
Melrose Park, PA

Re: Advice requested from those of you who have successfully checked camber at home
On 12/8/2016 2:12 PM, John Harmon wrote:

Sort of mixed units.

will be about 21,600 inches so each minute of arc will be
one inch. I don't think that helps you here.

--
Andrew Muzi
<www.yellowjersey.org/>
We've slightly trimmed the long signature. Click to see the full one.
Re: Advice requested from those of you who have successfully checked camber at home
AMuzi actually said:

But angles are the units that the manufacturer provides for toe while I'm
almost certainly going to measure toe with a distance measurement.

The manufacturer specifies the "total toe" as 0 degrees 14 minutes plus or
minus 10 minutes:

The manufacturer specifies a "total toe" required accuracy of plus or minus
2 minutes in a measuring range of plus or minus two degrees with a total
measuring range of plus or minus 18 degrees.

So this confusion is all my fault.

Clearly I'm confused because the way I think of toe is linear, but the
manufacturer specifies toe in angles, so I should not have brought up toe
in the first place.

Camber is simpler because the manufacturer specifies angles and the
measurement is in angles.

So we should stick with camber for this thread (because it's a simpler
problem).

Re: Advice requested from those of you who have successfully checked camber at home

not if you want to do it correctly, you won't.