Hey guys, I have an older (60/70s) caster/camber alignment gauge and I'd appreciate any input on it's CORRECT useage (ie, I've used it in the past, but probably wrong!). Camber, I get, that's not rocket science. The caster measurement has me a little confused however. It seems there's a few methods to the details which could skew your measurements a bit if the wrong directions were used. 1. Do you turn the wheels to 20deg (or is it 15deg)? 2 . Since it's got a dedicated caster gauge on it, do you still have to double the reading if you just turn in, as opposed to turning in 20deg then zeroing the gauge, then turning back to zero and another 20deg? (ie for a total of 40deg measurement). I'm probably overthinking the whole thing, but any details would be super helpful. Also, I have an Ideal Wheel Manufacturing Toe Gauge I picked up a while ago, and the scale on it appears it is not meant for measuring the toe at the tire surface itself (like when you do the tire scribe method) but is for the wheel flange surface itself. The weird thing is seems it would be ***uming a certain aspect ratio for the tire/wheel diameter ratio.
I'd say that Bear gauge is probably as old as I am or at least close to it My Snapon gauge and the little 30 buck one I got off Ebay work the same as every other front end gauge I have used.. That is turn the wheel in 20 degrees. ZERO the gauge and then turn the wheel out 20 degees and what you read is what it is. I have never heard of "doubling" the reading. I've used a twin to that Ideal Toe in gauge in some shop I worked in and you are partially correct. How you do it is to set it up between the tires or rims evenly off the shop floor and set the gauge to 0 then you roll the car so that it is sitting opposite of where it was before and read the gauge to see what the toe in or out is. I usually set it up with it at the back of the tires and rolled the car back until it was at the same height at the front. The best and probably main thing about it is that you don't have to hunt down a helper to hold the other end of the tape. I used it with front end pit where I could be under the car but on a lowered ride like a 51 Shoebox it is pretty well useless on a flat floor.
Thanks for your insight Mr48Chev. Seeing as you'd have to loosen screws each time you want to 'zero' the Bear gauge, I'd have to think you'd set it to zero with the wheels pointed forward, then just either turn in or out 20deg. The only other way to zero it would be when the wheels were pointed 20deg, you could rotate the whole gauge on the wheel mounting surface to get it to zero, but that doesn't seem right either. Additionally, I use a bungee cord through a wheel spoke to hole the gauge in place. Is that how they're supposed to be held on the wheel? I JUST had an alignment done on one of my cars last week (in HI, to get a car with modified suspension to p*** inspection you MUST have a shop perform an alignment for you). Anyways, I wasn't able to pay much attention to the guy who did the alignment, but he looked to be about 80 yrs old, and did the whole thing by hand, I think using an identical Bear gauge to the one here, hand scribing the tires, etc. (I was entertaining a 5yr old who of course couldn't be in the pit when he was working.) Regarding the toe gauge, it just so happens that the scale on the gauge vs a 'real measurement' ratio comes out to roughly 1.52:1. I calculated the measurement radius on the wheel surface to the tire radius for the tires I'm doing now, and it came out to a lucky 1.57:1. I'll have to recalculate this value on a low or very high profile tire, but for this combo, it's really close already. Is there any advantage to doing the 'roll back' method vs just checking it on the back of the wheel, then checking the front? Seems that as long as your wheels weren't bent, you could perform the measurement without rolling the car anywhere. (again, I could be overlooking something)
I'd have to study up on that Bear gauge a bit. You may turn the wheel in at the front, level the gauge and clamp it to the rim and then turn the wheel out and get your reading. That's what I'd try first.
That's a real old piece of Bear history. The link below shows what I learned on back around 1977. These, you took the camber/caster gauge from one side to the other, the wheel clamps stayed on the car and the toe gauges hung from them. http://www.teambearusa.com/upload/15084/do***ents/BearWA76_catalog.pdf
Yep, I saw that catalog too. Pg 32/34 show the gauge I've got. I even found the copyright info on it, lol. That's next to useless though, as unlike patents which are free to the public to research, the US copyright office charges you (a LOT) to get info on copyrights. The copyright was submitted by Applied Power Inc. A746830 on May 11, 76. There's a guy over on one of the 'vette forums who uses one, I'll see if he has any hints.
It looks like that gauge was designed for larger trucks according to the info in the link Bobss396 posted. This link to Longacre racing's instructions match the instructions for every bubble gauge I have ever used. http://www.longacreracing.com/instructions.aspx?item=8020
Just to close this topic out, I contacted Bear a while ago regarding the 'turn angle' for this gauge and they said that while they had no do***entation on this specific gauge any longer, that 20° would probably be correct seeing as their other gauges used 20°. That said, it seems to read almost the same value on the gauge whether you turn the wheel to 15° or 20°. Additionally, you only have to 'turn in' to get a reading. 1st, you spin the curved bubble track 90° to zero the scale to the fixed bubble level (the scale slides under the two large flat head screws). Then spin the curved bubble track 90°, turn the car's wheel 20°, put the gauge on the wheel (level it to the small, fixed bubble) and take a reading. (I know I made that more complicated sounding than it really is, sorry!
A big thanks for the update. I picked up the same gauge along with a set of turntables at a swap meet a few years ago and have been guessing at the proper set up with mixed results. Using this info next time I should get more accurate results far easier and quicker. Ed
You turn to 20° to the opposite side your on, so on the left side turn the tire to the right first and vise versa for the other side. So it goes like this, your on the left side of the car, you turn 20° right and take a reading, let's say it's 1° negative, this becomes your "zero", now turn left, let's say it reads 2° positive, since we started at 1° negative and now have 2° positive to the back that gives us a total of 3° positive caster. Back then people could do math, kids could count change back without the register telling them the amount so gauges like this require some math to use. I use a bee line plumb bob hand gauge every day. We have bubble gauges, wheel gauges etc. but I prefer the hand gauge, it's one of the most precise gauges out there.
Hey guys.... just clarification on the Bear 21ga Caster Camber tool... 1. Turn to right first 20deg zero the ga. 2. Turn back to left 40deg and take the reading. The reason you turn the wheel and zero.... you are measuring camber change from zero point. Bear changed to 10 deg sweep later when power steering was coming in. Today all US cars are 10 degrees with exception to multipoint suspensions which require 20deg like Tesla and VAG, Mercedes etc. But a 20deg sweep is the more accurate reading. The 21ga has no way of calculating out of a bent rim or hub. This is why wheel clamps were brought into the picture. You could mount the clamp, take a reading with the clamp at 12oclock and rotate to 6 o'clock...if they were different readings you woukd need to either add or subtract from your actual reading to get the most accurate... if 1deg diff fro 12 to 6 then -1/2 from your actual reading. Today computers do all the thinking.
That is standard procedure for any caster gauge I have used. Amazing that a new guy posts this on his first post to answer a year old thread on the subject though. Actually 23 Months old and dead. The simple trick is probably to buy one of those 12 buck caster camber gauges off Ebay, wait for it to show up from China and then play with it and the old Bear gauge to rather quickly figure out how the bear gauge actually works. Back in the 70's when I did front end work in the Firestone store in down town Waco I had a John Bean visualiner as the shops front end machine. Pre computer but a seriously good machine and great selling tool. I got a lot of work from guys who had been to a shop that was/is real close to the silos that belong to the Fixer Upper folks that still used a plum bob based front end alignment gauge. I just heard about it from a number of customers and never saw it but it was as absolute basic as you can get and probably seriously accurate if the guy using it knew what he was doing. They would get guys in the door for a 6.95 alignment and no one ever got an alignment in that place without replacing a bunch of parts.
I always turned up the caster on the p***enger side to where it felt ok, then started turning up the drivers side until it stopped pulling to the drivers side. Once I got to were it didn't pull and it felt stable at speed and didn't feel numb while turning I was home.. You can add too much positive caster, the steering will feel kind of numb and slow especially front steer cars.. With camber if I can get the caster up pretty high I only give a very slight negative camber, like .25. Because a high positive caster setting will tilt the wheels correctly as soon as its turned. Too much negative camber will make your car go all over the place when on the highway. So will too much toe in or toe out.. I only use a very slight amount of toe in because I use all Delrin bushings so there not too much slop in the steering.. You just want the toe to take out the loose feeling and thats it. Toe is funny, I'm always tempted to give it more when it feels good but once you just a very slight too far, it will feel all screwed up.. Bottom line is you want the wheels to be as straight and flat on the road when straight. When turning you want the top of both front wheels to camber in the direction of the turn.. When you see a dragster turn you'll see how both front wheels camber in the direction of the turn.. It's not about numbers its about what feels good and gets the car handling best.. If you can find somebody with the new Hunter Hawk Eye rack and knows how to use it, your in real luck... I have never got one of my cars back from the alignment shop and didn't have to touch something up to how I like it to feel...
We are getting a bit off base here but one thing to remember is that quite often when we see some article on setting up your front end in some magazine or online they are setting it up for something specific and it may or may not work the best for regular road driving where you want your very expensive tires to last as long as they possibly can mile wise. In how ever many thousands of front ends I did alignments on over the years I was shooting for having the car or truck drive straight, handle good and having the tires last as long as possible. I found that starting with 1/4 degree more + camber in the left wheel (left hand drive US cars) compensated for the crown in the road on most highways and caster close to factory specs got the wheels back to center good after a turn but didn't lay them over on turns so much that you wore the tread more than needed. If I knew that the person who drove the car intended to put a lot of road miles on it at or above the speed limit I put a bit more caster in it than the cars that just got driven around town 90% of the time. Toe in I never varied much if any from what others were doing on Hamb friendly cars usually going with 1/8 on Rear wheel drive rigs. Settings for drag cars are usually drag car specific just as settings for cars or trucks intended for running in the Autocross type events, that 1 to 2 degees neg camber that those guys run is way out of alignment for your ride with it's set of Pie crusts that you just gave Coker a big stack of fun tickets for. With a little homework and practice a guy should get pretty handy with that old Bear gauge though. It's all in knowing how to use it and the guy doing the alignment work is a lot more important than the machine he uses, Those fancy computer rigs are nice and let you do a lot of things that you can't really do with a simple gauge but they still don't compensate for lack of knowledge on how to make it drive right. I had my OT car aligned at a shop a few years ago and it came back with the steering wheel not centered when you drove down the road and to me that is a absolute no go, If the wheel isn't centered you didn't finish the alignment.
Totally agree on that last one....took one of my cars to a recommended shop and like you said, they couldn't even gt the wheel straight. Unbelievable...so much for the new "techs"...on the other hand, have my old school shop do the work, and we got to chatting, took it off the rack and the steering wheel was off centered.. I said no big deal, I can fix it at home. My guy said absolutely NOT, back up on the rack it went and in less than 3 minutes it was perfect. No subs***ute for pride, knowledge and experience!!
Ya having that box centered is important. I'm sure you know this but the center of a steering box has a crown to make tight when driving straight on the hi way. Your fortunate to have a good tech that knows how to use a rack. The big deal with a alignment rack is it measures all four wheels like a box. I usually have adjustable rear control arms on cars I'm going to keep, unless they have leaf springs.
Caster was a ****** to adjust on some cars off the alignment rack. So it was key to get it right once. Cars with shims, those could be jockeyed fore and aft on the upper arms. On cars like a '65 to '70 GM with caster struts, I would add shims on the upper arm so I could fine tune them if needed.
On C1 corvettes, '55 to '62, you've got to know an old school alignment guy... The reason being is that to adjust caster and camber, you have to remove the rear zerk fitting on the upper control arm and use a long allen wrench to get to the adjustment arm. If your guy knows that, it tells you something about his experience.
This is what it was like on the camber adjustments on Cadillacs. There was a special wrench, open end, one end was 1 3/8" the other was 1 1/2". The bigger end was for '70 down to '65 cars, the other '64 to probably '60. I think the oldest Caddy I ever aligned was a '61. There was an eccentric on the upper ball joint. It had to be loosened and the joint broken so the eccentric would turn. I had 2 owners say that this was the 1st time they saw someone do that on their car.
The last couple posts are going in my note book. You guys are the best sharing alignment tips like that..
Ah those damned Cadllacs, I've probably aligned five of them in my life and had one on the Rack when Carl Swingler the SnapOn man in Waco for a lot of years walked in the shop and had an instant sale. This Cadillac Alignment tool has been in my box since 1973. They weren't hard to set and usually stayed in alignment until something wore out.
I've probably done over 100 Caddy alignments in my time. The caster was done by the lower arm strut rod through 1970, IIRC. After fighting with frozen nuts, we would buy new ones through the dealer, a complete strut ***embly with everything, it made a bear of a job easy. Take measurements off the old ones, replicate it on the new ones and it would be close, or a good place to start.
I taught auto mechanics to inmates at a prison here in California for 15 years. We had an old Bean Visualizer that died many years ago and the state never had enough money to fix or replace it. So I took things in hand for myself. I taught front end alignment using an old Snap on spindle gauge, a scribe, and a toe gauge rescued from the s**** pile. I told my students that if they learned to use this equipment, the fancy new electronic read out machines would be a snap to run. I would work with 4 students at a time until they understood the geometry principles and the equipment. After they had it down pat, I had them screw up the alignment for the next group. It worked out to be a good learning experience and each finished group would hang around to see if the next group could figure out what was wrong and correct it. Lots of kibitzing when on, but they left with a solid understanding alignment. A spindle gauge , toe gauge, and a scribe to mark the tires to check toe can be a great ***et in learning. By the way, the year after I retired the state bought a state of the art alignment machine. My luck!
The Jalopy Journal
