I have figures of 1.5mm toe in (front) and 3mm toe in (rear) to work to. What would this be roughly in degrees (14" wheels)?
Cheers

Varies depending on your wheel size but not by much.
Roughly speaking 1'=6mm or 1mm=10"

adrian

take it your measurement is overall toe not per wheel?

If so,

Front, toe per wheel = 0.75mm

Wheel dia = 356mm

Toe in deg = inverse tangent of 0.75/356 = 0.12 degrees

rear = 0.24 degrees

can someone explain that in more noddy terms. ....

When i do the maths i get a fraction over 0.10 degrees for the front wheel.

yea, 0.12 degrees as I said!

That is exactly right

PS adithorp's rule of thumb is spot on, 6mm is about 1 degree, 1mm is 10 minutes of a degree, just thought I'd show where it comes from.

ok,

0.75/356 = 0.0021067415730337078651685393258427

(windows calculator)

inv tan of above = 12 degrees.......

no idea what i was doing when i tried it in the office, everyone ignore me.

lol you mean 0.12 degrees...............

[cough]

i dropped the 0. ..... whats a 0. between friends?

IMHO


The thing is, with normal workshop tools, you can measure in mm, but not in degrees.

So is it not more practical to quote toe figures in mm?


Paul G

Probably, but someone had lent me an optical alignment gauge which reads directly in degrees!

quote:

---

Originally posted by Richard Quinn
Probably, but someone had lent me an optical alignment gauge which reads directly in degrees!

---

quote:

---

Originally posted by rusty nuts

quote:

---

Originally posted by Richard Quinn
Probably, but someone had lent me an optical alignment gauge which reads directly in degrees!

---

Some of the optical tracking gauges , Dunlop for one , has both degrees and mm/in. Just rotate a dial to set wheel diameter and read off whichever

PS Make sure you calibrate the gauges before using if they are the Dunlop type. Put the gauges together and take a reading, centralise the scale to zero.

[Edited on 28/3/09 by rusty nuts]

---

Yes , set the dial to the wheel diameter , take a reading from the scale at the end of the gauges and compare with the rotary scale. To centralise the gauges place them on the car and adjust the contacts that rests on the wheel so they touch the wheel rim (avoiding any balance weights) then place the gauges together making sure the contacts touch and look down the periscope, move the scale arm until the line visible lines up with the marks on the face of the gauge then take a reading. If the reading is not zero slacken the nuts under the scale and adjust. place the gauges on the car and away you go.

Is the "wheel diameter" considered to be the distance between the two points where the arms touch the rim?

yes.

quote:

---

Originally posted by 907
IMHO


The thing is, with normal workshop tools, you can measure in mm, but not in degrees.

So is it not more practical to quote toe figures in mm?


Paul G

---

Hi guys, just been looking at my setup as I just set it by eye previously.

I get 5mm of overall toe out measured at the surface of the tyre which is 591mm diameter. I make this 0.48 degrees in total which is 0.24 degrees per wheel. Correct?

What I am unsure of is whether, when discussing toe angles, do people tend to talk about overall angles or per-wheel angles? For example, if someone said that 1 degree toe-in was considered a good starting point then would this be 1 degree overall or 1 degree per wheel?

In Des Hamill's book he talks about having up to 3.2mm of toe-out but I'm not clear if he means 3.2mm per wheel or 3.2mm total. Anyone know?

Cheers,
Craig.

The quoted angle or mm is normally total degrees/mm and the measurement is taken at the wheel rim not the tyre . IMHO 1degree toe in is a bit excessive although there is always the exception , I would start at around 1/2 degree .

thanks for that, that's what I thought. The 1 degree figure was just for illustration, I believe a small amount of toe out is actually better, especially for a non ackerman setup like mine. I'm probably not far off optimal where I am. Once I get it on the road (hopefully this week...) I can play with the settings.

Thanks again,
Craig.