Alignment System

[hardingfv32]

This team is using a string as a datum to align the suspension. How are measurements made between the alignment hub/fixture and the string? The hub/fixture seems to have an output cable. Can the string be detected by a laser or something?

http://i.imgur.com/3WXBmc5.jpg

Brian

[marcush.]

this Team is REDBull?

what is it about lasers ? as string is a fine tool to make a precise and repaetable measurement of toe and the setup you see here is a perfect example of it.

I well remmaber working with a super dooper mega dollar setuptool with "laser" strings .If it were not that expensive I would have surely thrown it into the bin after week one....

to answer your question:A steel ruler or a nice digital caliper does the trick ....sure you could catch the distance with one of the new contactless distance sensors
but ....

you can see two pads (machined surfaces) on the face of the setup wheel -I´d use a caliper to measure down from the string .Your precision is governed by the distance between the two pads methinks .make it 1 metre and your misalignment deviation is a fraction of the give within the suspension...

[autogyro]

I must admit to using an even cruder method on tests years ago.
A long length of wood 2x4 along the length of the car at half wheel height placed against the rear wheel rim.

Measure the distance between the wood edge to the front and the rear of the front wheel rim.
The difference gives you the toe in/out.
Works for cars with the same or wider rear over all track width.

Turn the wood over and take the average of the two readings, to allow for a non strait piece of wood.

[marcush.]

I found a roll of fishingstring a lot more convenient to carry to the tracks...
sure the bars work just as fine ....but man they are looong ..current formula 1 cars have wheelbases like medium sized trucks...

[rjsa]

Measuring the difference in a magnetic field generated by that wire intensity?

That plate coupled to the hub has some wiring running in.

[spacer]

the wiring is probably for another part of the setup rig.

No matter how high-end we think F1 or any other series is, the teams damn well know to never try to waste money or any other resource for that matter making things way more complicated, space-age or shiny than they need to be. Every raceteam high or low around the globe has been able to perfectly align toe with the string-and-ruler method well within small enough tolerances. Why should F1 be any different.

[Lycoming]

No matter how high-end we think F1 or any other series is, the teams damn well know to never try to waste money or any other resource for that matter making things way more complicated, space-age or shiny than they need to be.

Which is why their alignment gear is made of carbon fiber and they use jet nuts in places where a nylock would do.

[marcush.]

the wire..
I´d hazard a guess -it´s for the load cells to measure cornerweights.

http://www.novatechloadcells.co.uk/ds/set.htm

the basic concept of string alignment -fitted to the car is according to my experience a neat and cheap way to make quick
precise adjustment and checks .Clearly most formula 1 teams do think along those lines .In the background of the RedBull pit picture you can see the horizontal bar carrying the strings at the backend of the car.

universal kits are available

http://www.b-gdirect.com/category-287/b ... s-kit.html

but honnestly ,if you can´t even fix a square tube temporarily to your car at hub height ,you should not start thinking about turning any nut or bold on your car... that´s two straight tubes fixed to the body front and rear a few yards of thin nylon string and a decent steel ruler ....I ´m sure the hardware will not need to set you back in excess of 30$ to arrive at a potent tool.that will do the job all day.

You can go from there and build setup wheels making a full setup a quick and precise exercise taking only minutes.

[hardingfv32]

While I appreciate the use of a steel ruler, there does seem to be the opportunity for parallax error which would seem unacceptable at this level. The use of a ruler also implies a form of manual data entry into the system.

So there is no electronic way to measure the distance from the string to the alignment hub?

Brian

[Jersey Tom]

While I appreciate the use of a steel ruler, there does seem to be the opportunity for parallax error which would seem unacceptable at this level. The use of a ruler also implies a form of manual data entry into the system.

So what?

[DaveW]

I have never had to do it, largely because I have access to guys who know what they are doing. They have equipment available to them that they certainly use, but they also like to check alignment with "strings".

It reminds me of the exercise we carried out to "level" the four platforms of our rig. Spirit levels are just not accurate enough. Lasers project a straight line, but the "flatness" of the line is set by spirit levels. Eventually, we concluded that the best way was to use water levels, a technique that was used by Egyptian builders to level the base of the pyramids. Keep It Simple.

Incidentally, we also concluded (over time) that nobody's flat patch is actually flat...

[stolenmojo]

While I appreciate the use of a steel ruler, there does seem to be the opportunity for parallax error which would seem unacceptable at this level. The use of a ruler also implies a form of manual data entry into the system.

So there is no electronic way to measure the distance from the string to the alignment hub?

Brian

It also implies that the key to making the car go quickly isn't in this part of the setup.

[marcush.]

While I appreciate the use of a steel ruler, there does seem to be the opportunity for parallax error which would seem unacceptable at this level. The use of a ruler also implies a form of manual data entry into the system.

So there is no electronic way to measure the distance from the string to the alignment hub?

Brian

It also implies that the key to making the car go quickly isn't in this part of the setup.

wrong .
the fact you use a string does not imply it is not precise .horses for courses.You would do a sensivity check and if you find out .5 of a millimeter in precision over half a meter whel diameter will take you there -anything more than a ruler and a string will not improve your results.waste of recources and time....

But you need repeatability in your setup .mind you if your setupwheel has a defined pair of pads on axle height and you measure the distance to the string which is also on axle height ,your only source of parallax is the ruler not at right angles with the string in horizontal plane....you can easily avoid that taking a wider ruler marked at both edges and a true and flat face..towards the setupwheel (which is then of course inducing a slightly "off" angle as wheels are rarely set precisely paralell .This geometric fault is not worth speaking of ...sensivity.

you just don´t need to do certain thing just because you can do it.

[hardingfv32]

So what?

So when F1 concerns themselves with measurements to the second decimal concerning aero coefficients, you do not think similar accuracy is necessary when doing suspension alignment?

Are you able to volunteer what level of accuracy is used in NASCAR for suspension alignment?

Brian

[Lycoming]

Presumably, they've done a sensitivity analysis that showed that a 0.01 increase in Cl gives them some small but measurable benefit. At the same time, I suspect they're quite aware that there's a limit to how accurate you need to be with suspension alignment. The fact that they're using strings should be evidence enough to say that it is indeed sufficiently accurate.

Not every single thing on the car needs to be held to the finest possible tolerance, despite what some documentaries and promotional material might have you believe. Parts can be made to less than 0.001" tolerance, but do you think they hold that tight of a tolerance on, say, the wheelbase? Do you think they need to?