because i don't know what i'm doing. i have an alignment gauge i bought at a swapmeet. i made some turntables out of particle board with degree wheels glued on top. i understand toe-in. i understand camber. i still don't get caster,especially since my manual says i need NEGATIVE caster. huh?
Caster is tilt of the spindle centerline, usually to the rear, to help steering stability. I'm not sure what you are working on but I'll try to explain the easiest way I know. If you look at the upper control arms on most mid 50's & newer cars, where they bolt to the frame, there are shims. Notice that in most cases there are more shims on the front bolt than the rear. If you were just putting a frontend together you'd put an even number of shims on both control arm bolts to bring the control arm out to get the camber adjustment right. Then you'd add more shims on to the front bolt to,in effect, move the upper balljoint, or spindle centerline, back. Therefore giving you a caster setting. I hope I explained this so you understand it. The shims are used mostly on balljoint suspensions. Kingpin type A-arm front ends usually have an adjustment bolt in the upper outer knuckle support bushing, GM, or by turning the upper inner shaft. Ford. Hope this helps. Billy
well alot of companys put negative caster settings on cars with out power steering because it would make is easier to turn. As far as alingment tools im not sure the one you are using you can get a nice one. with a bubble gauage that will set total toe. but only a machine can set individual toe. skootch at Skratch's garage.
Yorg, Good luck with that. I'm such a chump that I usually just take my **** to the alignment shop. I've got to talk to you about kingpins at some point. -r
maybe i should go to an alignment shop and offer to buy the guy lunch in return for showing me how my gauge works. randy,are you talking about the spindle flopping project? the problem is,i KNOW i'm supposed to turn the wheels 20% i don't know WHICH WAY? say i have the gauge mounted on the left front wheel,and i set the bubble to zero. do i turn the wheel 20% to the left? or do i turn the wheel 20% to the right? and which way is the bubble supposed to go for NEGATIVE caster,which my factory service manual says i need? has anyone here ever worked in an alignment shop?
If you turn it one way 20º and it tilts 8º and you turn it 20º the other way and it tilts 4º the total is 12º tilt. Half of that is where the spindle caster axis is aimed so 6º from the 8º is 2º tilt in whatever direction that 8º was tilted. Those tilting degrees are a result of the way the wheel tilts when turned on the axis of the kingpin inclination so they will be different degrees for different cars so you have to turn both ways and check the difference, not just one of the angles.
well Mike,i just gotta say WOW! remind me to buy you a burger one of these days,or a free front end alignment,your choice it's all becoming clear to me now...
thanks go to you too DrJ,i'm sure i would have figured it out eventually,but the graphics really make the difference.
Okay, as long as it's not at that grill on the Alameda, near the Arena. Yes, a well written description indeed.
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