Machined surface. True within a couple thou.
Surface of the WHEEL. Should get you to the alignment shop.
How do you think alignment shops do it?? They align off the wheel, whether it be a string machine or a beam machine, they align off the wheel ( usually the rim lip area). Actually not as accurate as the area I am using. The area I am using is machined, as is the wheel area that is bolted to the hub or drum. Like all aluminum wheels, all machined surfaces are done in the same plane ( parallel to one another ). If all the surface areas I mentioned are clean and the wheel is not bent, the alignment will be on the $. Trust me, I used to do this for a living.
I think the MODERN alignment shops use equipment with electrical sensors to compensate for any wheel run-out, along with a lot of other things we can not measure without sensors and computers. Seeing you are only doing a two wheel alignment, the little bit of compensation run-out you may experience with your set-up is moot compared to not measuring thrust ,off-set and set-back.How do you think alignment shops do it?? They align off the wheel, whether it be a string machine or a beam machine, they align off the wheel ( usually the rim lip area). Actually not as accurate as the area I am using. The area I am using is machined, as is the wheel area that is bolted to the hub or drum. Like all aluminum wheels, all machined surfaces are done in the same plane ( parallel to one another ). If all the surface areas I mentioned are clean and the wheel is not bent, the alignment will be on the $. Trust me, I used to do this for a living.
Assume this is a test?, but without getting in to a pissing match, let me say that wheel alignments are only as good as the person doing them, whether you are doing it at home with a few $100 dollars worth of equipment or modern alignment shops using $100k worth of equipment. I found this out the hard way with my race car. I now do ALL my own alignments. Just about anything you can measure with a sensor / computer, you can also measure ( and compensate for - if you are inclined to fix it properly ) mechanically. This includes wheel run out, off-set, set back, SAI. Once you have made your rear axle measurements ( no off-set or set back ), a 4 wheel alignment is pretty much a moog point - no need to measure off of something that you already know is sitting in there straight. A 2 wheel alignment will work just fine. Attached pic is of my toe gauge. I usually shoot for 1/16" in for the street. Race car = 0.
I also use this same gauge for checking WB side to side by adding a section of square tubing in the middle.
This particular car has a canted 4 link out back ( all 4 adjustable ) and a some what typical short arm / long arm front ( with multiple adjustments on both arms , so lots to play with.
Hey Bodyperson, Wow, We had an A-111 in my shop for many years ( think it was a string machine ) before finally upgrading to an all computerized machine. I've been retired for over 15 years, but I think we went to a Bear machine from the Snap-on unit. You are right about my not being able to compete with the new stuff. For one, you don't even need a level surface to do it anymore. Computer figures that out for you automatically. For sure faster with a lot more info right at your fingertips. No doubt the computerized stuff is more accurate IF the operator knows what he is doing, not cutting corners ( "set the toe and go"), punches in the correct parameters, and has periodically maintained the equipment he is using. I just feel more comfortable doing it myself, and I feel I can get pretty close on the accuracy thing - not having to book any hours.
Ya it was the string machine by hunter. 30 years ago it was state of the art. That Lee Hunter guy was a smart fellow.Hey Bodyperson, Wow, We had an A-111 in my shop for many years ( think it was a string machine ) before finally upgrading to an all computerized machine. I've been retired for over 15 years, but I think we went to a Bear machine from the Snap-on unit. You are right about my not being able to compete with the new stuff. For one, you don't even need a level surface to do it anymore. Computer figures that out for you automatically. For sure faster with a lot more info right at your fingertips. No doubt the computerized stuff is more accurate IF the operator knows what he is doing, not cutting corners ( "set the toe and go"), punches in the correct parameters, and has periodically maintained the equipment he is using. I just feel more comfortable doing it myself, and I feel I can get pretty close on the accuracy thing - not having to book any hours.
Ya, have no idea why I said Snap-on???
Actually had a Hunter rack to go with it - and extra strings of course.
Those Hunter racks are nice with air bag lift and the swing jacks. Those racks were made for production.Ya, have no idea why I said Snap-on???
Yep. At the time ( about 84 - 85 ) I was running a 17 bay Government shop in the Chicago area. Many a squad car went on and off that rack. If there was a draw-back to it, you had to have a dedicated bay for it. We did do some brake work on it also. Later stuff ( all electronic and computerized ) was much more portable.
Wow!! That could be older than me!
Ya, obviously we can't afford what our shops had - nor would you want to for home use. I like my magnetic "Deco" caster / camber gauge, but it has some short comings - which perpetrated this thread. My turn tables are "Rand" units that I bought on E-bag. Heavy duty quality ball bearing units for a great price. There are more toe gauges out there than you and I have toes. A good quality tape measure can fill most of the other bills. It's time consuming work to do it at home, but at least you know it's right, and you can play with settings all you want. I know for a fact that my street rod diff is off side to side about 3/8". Not gonna worry about it for that amount, as I would have to relocate all 4 link perches on the housing to correct it. Set back is on the $. I started out with 3* of caster and I didn't like the poor wheel return on corners. Upped it to 6* and the wheel returns real nice with no noticeable increase in steering effort. All stuff you can do without a major tool investment.
