At home alignment

[98gpgt]

A subject that is likely to make some groan I know.

 

But correct me if I'm wrong. To correct the alignment (toe), the outer tie rod has to be rotated one way or the other, so many turns, to make all the tires parallel. To be perfectly aligned (yes I know at the front they're supposed to be a little nearer). But ignoring that for the time being, and assuming my assumption isn't presumptuous, why won't a string tied around all 4 wheels be sufficient to determine if the wheel faces are all ligned up? Please don't just say it won't or can't work, tell me why. If the tires aren't aligned, and the tires scrub, well that has to be due to a discernible difference in the degree of alignment (or actually lack thereof). And if the alignment is only correct to the accuracy of 1 thread on the tie rod, how exacting could this process be that you couldn't do it with rudimentary tools?

 

I understand on some cars the body gets in the way. Ok, so extend the face of the tires out with equal sized blocks of wood.

 

If I'm mistaken about any of these points, please point them out.

[vipmiller803]

Alignment has more than just toe. Camber and caster play crucial roles in handling, tire wear, and drive-ability. Yes, you can adjust toe using the rear wheels, but what makes you think your rear wheels are even straight? They usually have adjustment too. Alignment shops exist for a reason. I'm not saying you don't have a point to some degree. I'm not even saying I have not done something very similar to what you're suggesting, but it is a fact that the cost of an alignment is far less than that of eating tires too soon, especially if it's quality rubber. Yes, it can be done, but you have to set up some very calibrated space in order to get your four tires lined up correctly for all three adjustments simultaneously. Wait a second, isn't that what an alignment machine is?

Edited May 11, 2018 by vipmiller803

[GTP091]

If you're going to do this just for the reason to get you by enough so you can make the drive to get an alignment at least use a laser rather than a piece of string.

[Imp558]

An actual "diy alignment toe tool" will measure the front against the rear of the same pair of wheels because like you pointed out the width is different front to rear. Remember to make sure your steering wheel is perfectly straight before you call it good. If you post what vehicle I likely have alignment specs. They go by degree though, not inches.

Edited May 11, 2018 by Imp558

[55trucker]

A subject that is likely to make some groan I know.

 

 why won't a string tied around all 4 wheels be sufficient to determine if the wheel faces are all ligned up?

 

 

If I'm mistaken about any of these points, please point them out.

The tires being the most important items where ones alignment is concerned will not last very long if the toe is not correct, even being out as much as 1 degree can cause a pull in either direction. 1 degree on the tie rods thread could be as little as 1/2 turn.

 

The vehicles front  track width is wider than the rear track width, so tying a string around all corners is not going to provide you with what you're looking for, what you end up with is an exaggerated rectangle wider at the front, narrower at the rear.

[98gpgt]

So what are you adjusting other then the tie rods? If as you say a half thread off and your tires are history, how are you compensating if adjusting the tie rods can't produce the necessary adjustment? If there's something I'm missing let me know. And I did some quick math and I don't think what you're saying is accurate. I'd need a pencil and paper, and be vertical to prove it. But assuming 20 tpi, 1 thread is .050". Assuming the tire 24" in diameter, you would need to be off by 4 threads to have an error of 1 degree. I think.

[Imp558]

Deflection, trucker is close. The # of turns isn't an arguable thing with different thread pitches and all, the only thing that matters is in degrees of the wheel projected path.

[98gpgt]

But you can't get anymore accurate then 1 thread. So what's being said doesn't seem to make sense. I'd like to know where he's getting that info from. And by the way it's a 98 GP GT.

[cheatah faheatah]

But you can't get anymore accurate then 1 thread. So what's being said doesn't seem to make sense. I'd like to know where he's getting that info from. And by the way it's a 98 GP GT.

Tie rod adjustment CAN be less than 1 thread. Adjustments at a shop are done with tie rod ends in place, loosening the jam nut and rotating the rod inside both the tie rod end and the ball/socket end at the end of the steering rack.

[98gpgt]

Ok. But 1 thread is still roughly 1/3 of a degree in my case. My tie rods have a pitch of 1.5mm. The overall point is error in alignment is discernible. And am I mistaken but don't they pull the front of the tires in about 2 tenths of an inch. That's huge compared to the error of 1 thread off, more then 3x anyway.

 

 

I found these here http://www.clubgp.com/newforum/tm.asp?m=5210980&cookieCheck=718424890

 

 

 

Front Camber: -1.40 to -0.40 is the range and perfered is -0.90

Front Caster: 2.50 to 3.50 is the range and perfered is 3.00

Front Toe: -0.10 to +0.30 is the range and prefered is +0.10

[98gpgt]

And that page didn't say for which year ...

[GTP091]

To answer your original question; a string and a block of wood held onto the tire somehow isn't a very precisely calibrated tool designed specifically for this purpose being used by a trained professional that completely understands wheel alignment and has been doing it daily for years. 

 

I just can't imagine why you'd argue the benefits of using string or other crude methods over just paying the $100 bucks to get it done perfectly.  Unless you're wanting to know so you can get close enough so you can get it in the shop after you've replaced rod ends or had major suspension changes. The ends don't justify the means here at all if you're trying to save a few dollars.  Your car will handle like a lumber wagon and the tires will be garbage much sooner if you do it yourself. 

[55trucker]

aside all the banter.....

 

is there anything at all that is preventing you from visiting an alignment shop?

[98gpgt]

Why not just respond instead of suggesting there' something wrong with asking. Call it arguing if you like. And just who is it that's creating the banter? The questions I've asked are legitimate, and cheatah contributed something useful. If you can't stand a little discussion, why join in?

[Imp558]

There's nothing at all wrong with doing alignments at home. I'm hoping to get tooled up for it soon. Realistically doing it without the proper tools one needs to expect to have it somewhat less than perfect so we really need to weigh professional alignment costs against proper tooling.

[Imp558]

Oh, alignment tools don't have to be the full blown balls to the walls professional alignment machine. One can get tooled up for a few hundred dollars. I remember thinking last year about $500. Alignments for life for $500 is good imo.

[98gpgt]

Listen if I'm wrong then I've at least accomplished the task of learning something new. Machinists employ tricks all the time, particularly when forced to work on equipment that's worn and out of spec. Many an instance where you're told "that will never work", and you need expensive equipment to accomplish a task. I realize specialize tools can often make a job easier and strait forward, and for businesses it doesn't make sense not to invest. But these adjustments are trivial. And do alignment shops use the tires face to take measurements? I doubt it, don't know, but I'd so what is all the lasers and fancy equipment for? Another method I was thinking of was using threaded rod and working off the rotors, much more involved though.

[GTP091]

The question has been answered.  A piece of string will no matter how well executed is not good enough to get an accurate alignment. If it was every shop in the country would use it. How would you measure if your string is still straight as soon as it touches the tire .   A piece of string will work about as well as holding up your thumb, sticking your tongue out, and turning your head sideways to see if a wall is level, neither one of these methods is accurate.

 

If this is just for curiosity's sake then fine but it sounds like you plan to roll this out as a permanent correction for your car and we can't understand why, when its so cheap to just do it right.   If you can answer this question you'll probably get more useable answers. 

 

I myself have used a laser level mounted to the rear tire and equal length bar stock to measure the toe on the front.   I did this only so I could get the car in for an alignment.   I was able to get it seemingly close within a mm and the tie rod was turned a 1/2 turn to make the change.  But what a pain to turn the tie rod when the car is loaded up on the suspension.   The car still pulled and the steering wheel wasn't perfectly straight and I thought I did a decent job.  It still needed a professional alignment. 

[cheatah faheatah]

 And do alignment shops use the tires face to take measurements?

Sensors are chocked up to the wheel rims.

[cheatah faheatah]

Even the best homegrown board & string & level & bubble gum & whatever else won't save enough money to make it worth while. Weigh it against accelerated tire wear, poor traction/braking in adverse conditions, and possible less than ideal handling in emergency situations. Around here Town Fair Tire gives a free alignment with a tire purchase ( they don't do any other mechanical service, so no hard sell on you need this and that) or just $69 without buying tires. I swapped 1 (ONE) tie rod end recently and did the count thread thing. Steering wheel ended up off a tick & tire would squeal only during left turns. When I picked it up Tech guy told me it was WAYYYY off. What we try at home gets us close enough to make the drive in for an alignment. Leave the rest to the pros, It's short money in the long run.

[Imp558]

Really the tools are not expensive. The plates the car sits on are pricey. They have the degrees of toe on them so they're somewhat necessary.

[cheatah faheatah]

https://www.facebook.com/photo.php?fbid=1735334736561534&set=gm.2925023037636671&type=3&ifg=1

[Schurkey]

Sensors are chocked up to the wheel rims.

They're (usually) ATTACHED to the rim of the wheel, and shitty D-I-Y alignment tools actually use the rim of the wheel for centering the gauge.  REAL alignment tools attach to the rim, but are adjusted so they're concentric and true with the wheel axis--the "spindle" or the true axis of the wheel bearings.

 

Of course, there are those few vehicles that have old-style steel wheels, the spindle and hub is actually accessible--the gauges can mount directly to the hub.  As long as the wheel bearings are tight, that's as precise as the gauge needs to be mounted.

 

Really the tools are not expensive. The plates the car sits on are pricey. They have the degrees of toe on them so they're somewhat necessary.

FIRST, you have to have level pavement.  That's difficult enough.  Any front-to-rear slope will give you false caster readings.  Any side-to-side slope will give you false camber readings.

 

Slip plates don't have to be expensive, although good ones are.  If you have a level surface to put them on, a layer of sheetmetal, some grease, and another layer of sheetmetal is good enough.  Yes, it helps if the degrees are marked-out on the plates.  There are work-arounds if they aren't.

 

The big deal is to be at least as smart as the equipment.  If you think toe needs to be set by full-turns of the tie-rod threads, you're not ready to do your own alignment.  There's all kinds of Youtube videos about aligning your own vehicle, but the last time I went looking at them, I had to shut them off before I went insane.  All the ones I found had obvious errors and assumptions.  I just couldn't watch that much stupidity.

 

I got my slip-plates and gauge mounting brackets from a shop that was going out-of-business.  Bought a magnetic camber/caster gauge from eBay.  The magnetic gauge is a good system, but without the good gauge mounting brackets, they're  nearly useless.  My mounting brackets are going to need some modifications to make them fit larger-diameter wheels.  I'm pretty sure they won't expand large enough to fit 18" wheels, although they'll do 13" and maybe 12" wheels just fine.  Not a lot of cars using those tire sizes any more.

 

Link to an eBay seller of a magnetic camber/caster gauge similar to mine:

https://www.ebay.com/itm/Longacre-Caster-Camber-Gauge-with-Magnetic-Adapter-78260-Front-End-Alignment/132444234644?epid=708201917&hash=item1ed64aa394:g:EhcAAOSw5VtaPp6T

 

Beware, there's five hundred eBay sellers all peddling the same crappy gauge, and it's NOT the gauge I linked to.

 

Of course, toe is still measured using a trammel.  It's a huge PITA.  Ideally, you crayon a stripe all the way around the tire, and then etch the crayon mark with a tack or nail held absolutely still as the tire is rotated.  Then you have a fine line to measure from, perfectly even on both the front and the rear of the tire.

[Imp558]

These longacre tools are some of the ones I liked best when I was looking. The turn plates there are insanely expensive, I had found some more reasonably priced plates that had the degrees on amazon and figured something would present itself when I was actually ready.

 

http://www.longacreracing.com/products.aspx?itemid=2446&prodid=7252&pagetitle=Digital-C%2fC-Gauge-w-AccuLevel%e2%84%a2-and-Quick-Set%e2%84%a2-Adapter

 

http://www.longacreracing.com/products.aspx?itemid=2445&prodid=7237&pagetitle=Toe-Gauge

 

 

As far as level goes that's the least of my worries, I was an ironworker so virtually everyone I know owns a transit, lol.

I have a stack of sheetmetal filing cabinet separators two inches thick so I figured I'd make spots on the floor where the car's wheels sit and use a transit to simply shoot the elevation and write the difference right on the floor so I knew how many filing cabinet pieces to shim under the turn plates at 3 wheels or less. (Hopefully less)

 

I've been interested in aquiring the technology for quite a while:

 

http://www.w-body.com/topic/51729-should-i-buy-this-alignment-machine/?hl=%2Balignment+%2Bmachine