when doing your own alignments

[Chevy]

I started doing my own alignments last year on my '68 Camaro. I purchased camber gauge, fabbed up plates to measure toe, and borrow a friend's turntables (thanks Russell!).

One thing i noticed was that each time i make a change, it doesn't "register" until i take the car for a ride. Just dropping the car, bouncing on it, or even rolling it a little bit will not show a repeatable change. This, of course, gets tiresome as you iterate through your settings, especially if you have a car way off. My assumption is that stiction in the suspension is the main culprit?

My question for others that do their own alignments is: do you have the same issue? and have you come up with any clever ways to address it?

Also does anyone know if this is an issue when you have your car aligned professionally? Do they have a shaker table or something to settle the car after they make changes? Otherwise they aren't very accurate at all?

Thanks!
Paul

[JRouche]

I started doing my own alignments last year on my '68 Camaro. I purchased camber gauge, fabbed up plates to measure toe, and borrow a friend's turntables (thanks Russell!).

One thing i noticed was that each time i make a change, it doesn't "register" until i take the car for a ride. Just dropping the car, bouncing on it, or even rolling it a little bit will not show a repeatable change. This, of course, gets tiresome as you iterate through your settings, especially if you have a car way off. My assumption is that stiction in the suspension is the main culprit?

My question for others that do their own alignments is: do you have the same issue? and have you come up with any clever ways to address it?

Also does anyone know if this is an issue when you have your car aligned professionally? Do they have a shaker table or something to settle the car after they make changes? Otherwise they aren't very accurate at all?

Thanks!
Paul

I like the post, very good question. And Im not an expert but do my own alignments also. I have the turn plates, and do the set up like you. My suspension is a lil diff, not much in the way of stiction due to all the metal on metal bearings, no bushings. But even with a smooth bearing suspension I think stiction has to have an effect. Good assumption. I do a full roll off, roll on (bout twelve feet ) to let the suspension move some.

How much of a variation in the numbers you get would determine if you need to roll the car out and seat the suspension. Yup, pain in the butt for sure. But I think that would give you the best "real" numbers. And good point, how do the shops counter this. Id like to know. Good question, solly I cant help any. But I will watch this thread to see what the pros do. JR

[silver69camaro]

Are your turntables floaters?

I ask because when doing an alignment, the turntable has to accomodate for side scrub as wheel as turning angle. If not, the suspension will be in bind until the car is rolling. I recommend getting two 12x12 sheets of 16-18ga steel with grease inbetween. This will allow the wheel to move however it needs to.

Second, soft bushings will make it somewhat difficult. The bushing can take up the change when the car is static, but then "relax" when the car is driving. Also, make sure the full weight of the car is on the suspension - don't use a shock jig of any sort with the hub hanging in the air.

Something that I always do is make sure the ride height is identical between adjustments. When the car is on the plates (and it's completely level - use a self leveling laser to get everything within 1/16"), I measure from LCA bolt to ground. After each adjustment, I measure the distance again...if it's not the exact same distance, it's bound up and your readings will be off.

I could go on and on, but these are the most common culprits that I see.

[a67]

Once i started to use turntables the alignment settings were dead-on. IOW, I could drive off the plates, around the block, back onto the plates, and get the exact same measurements that the front end was set to previously.

It may be that the turntables you are using do not move easily enough. It should be that the car can be easily moved while on the plates (which one needs to be careful off while doing the alignment). That is, the plates move such that they are as slippery as ice.

Bob

[John Wright]

I was going to mention to make sure the turn plates / turn tables are moving freely...but everyone has mentioned that already.

[JRouche]

You guys brought up some good points. Not meaning to hijack your thread Chevy, just trying to get some additional info and it may help you also.

The turn plates? What are full floaters? Are they plates that allow for sideways (lateral) movement also? My plates are some big ol heavy units from an alignment rack, an old one. They slide fore and aft and sideways on metal rails along with the bearing supported plate for rotation. And they slide smoothly on well grease rails. Is that a floating turn plate?

I do a roll on, roll off just because Im not sure the plates have taken up the movement. I just do it for double checking. And really, even after the roll on and off the numbers are the same. JR

[David Pozzi]

Do you have poly bushings?
Actually I meant to ask if your car has them...
David

[Chevy]

I'll try to respond to everyone at once:

All, yes, turntables are full floaters.

JR--full floaters have an extra layer supported on bearings to allow two degrees of freedom so there is no binding when the weight is put back on the tires-technically not just side to side but also fore and aft, although this doesn't come in to play as much as side to side. Lent to me by Russell of Hot Rod Jims (www.hrjinc.com (http://www.hrjinc.com)) because i've been watching for a year now and still haven't seen a used set on eBay and i can't bring myself to drop the cash for a new set...

Bob, the car can be pushed left/right with a finger or two when it's on the ground on the plates, so that is pretty close to ice.

David, the car has a DSE coilover conversion so is running the delrin bushings.

Matt, the car is 100% on the ground. Your suggestion of measuring up to a point on the suspension and ensuring this is consistent is a great suggestion and should certainly help in consistency, but i don't think it'll entirely solve the issue...i have been able to measure the difference in say, the camber, as the car is moved through the suspension travel, and it is repeatable. The phenomenon i'm describing is in addition to that variable.

Thanks all! Any other ideas or suggestions? Anyone know what the professional alignment shops do (if anything??!!) I'm thinking nothing and that is one more reason to do your own alignments...was working on putting an alignment on my newly-acquired '71 Corvette and am experiencing the same phenomenon...stock suspension there except for Herb Adams sway bar.

Paul

[JRouche]

Ok. From the sounds of it you may be shifting the alignment during driving. You have done everything to settle the car during alignment, you have the correct tools and methods.

The only thing I see is that the suspension is able to shift when you put some driving loads to it.

You have delrin bushings, they do tend to grab alil. But they wont stick so much, or I should say hold, like rubber or poly bushings. . If you have bounced the front end to allow them to settle.

One last thing I would look at is the roll bar if you have one. I have metal on metal bearing roll bar end links. But if you have rubber or poly end links they can interfere with the movement. Including the bar to frame bushings (more so). I have tested the influence the bar has with static alignments. And when I drop one link to free up the bar it does allow the suspension to move more freely.

And I would also love to hear how the pros do it on all the various cars that come through the shop. Some of the suspensions are really tight due to rubber bushings.

Makes me think twice about a shop alignment if they are not able to reduce the drag on the control arms because of tight bushings. Makes me think they set it up as is and send the guy down the road. They (mom and pop) dont look into alignment specs as critical as some of us do. JR

Oh, one last thought. I DO think aligning your suspension on your own is MUCH better than taking it to a shop. You take it to a shop and they will send you out the door and say its aligned. That works for most people. But folks in the know might have an issue with that. Like you!!

Sometimes the more knowledge is a pain in the butt. Cause now you know that a shop may not be providing you with a proper alignment. The proof is in the numbers. A shop doesnt have the concerns that you as the builder does. JR

Ok. One more last thing. Nail polish. What color do you like. Hahaha.. Ok, the color doest matter. But I have a few bottles of nail polish in the shop, I love the stuff. I use it for alot of stuff. One use is to mark pieces of metal, like suspension parts to see if they have moved. Steal one of your wifes bottles for the shop. After you set the car up mark the areas with a dot that you think might be shifting. One dot will cover both surfaces. I use the nail polish for marking, like down a deep hole to transfer the hole where a transfer punch wont work (like into a fabric base) or for a bolt movement indicator, I have used it alot for detailed applications of a marker that adheres better than some other markers.

[a67]

Something doesn't seem right (which you already know and why you posted). Did you lock the plates before driving the car onto them? There should be a pin to prevent them from moving. Then once the car is on the plates the pin gets pulled.

I'm thinking that maybe a plate is at the end of it's travel and not letting the alignment move.

I know that shops don't have shakers or anything. The plates that you are using, do they also rotate? Fore/aft, side to side, and rotation covers it.

The steering wheel should also be locked in place. Otherwise if it moves a little so will the camber & caster. There is a gizmo with hooks that goes between the steering wheel and seat. There are also ones that go between the steering wheel and brake pedal.

Can use the degree scales on the plates to keep an eye on the wheel location. To keep them pointing straight ahead.

Bob.