Posted to Tool & Equipment Forum on 9/6/2014
96 Replies
Why use an on-car spin balancer…? (This was requested
information)
In one sentence: Because nothing else compares. -- With the
exception of a force balance computer balancer, no other
type of balancer is as difficult to master. Once you have
there is NOTHING that can't be balanced to perfection.
The on-car spin balancer is more accurate than a protractor,
a bubble, or ANY kind of computer balancer. You just need to
use your brain. Be smarter than the problem.
Where to start… Hmmm; background. I began using on-car
balancers in 1972. I've balanced at least 40,000 tires using
this method, many with the Hunter Tuner, fewer with the
Alemite/Hunter strobe. In 1986 I stopped using both the
tuner (not accurate enough) and the strobe. All the strobe
does is help you to guess. I felt I no longer needed help
guessing, after over 15,000 balances
Spin the wheel up to (60, 90, 120, 140 MPH) and you will
find the harmonic point of shake. Usually at 55-70 MPH, but
you'll possibly get a secondary vibration around 120-130
MPH. Very tense vibration at that speed. A computer balancer
spins at a single RPM and has no harmonic sympathy. Larger
tires will shake at 35-45 MPH
The question that any interested person would ask, is, "How
do know where to put the weight, and how much weight should
it be?" Thanks for asking…
When I feel the severity of the vibration I can make a very
accurate guess on the weight needed. Let's say that my guess
is one ounce. I put a one ounce weight at the valve stem. If
the vibration remains the same, I'm about 90* off. If I move
it 90* to the left and the vibration gets a lot worse, then
the weight needs to be moved 180*. Make sense..?
If all of this sounds like a giant hassle and an old man's
'pipe dream,' I will meet you in Sacramento and rotate and
balance four 16" tires, alloy or steel, faster than you will
with a computer balancer and that vehicle will never come
back for a tire vibration.
You may also consider this: I can get my balancer, in
perfect working order, (I actually have two. Total
investment, $300) for $500. Your computer will set you back
at least times that much. My balancer never malfunctions or
needs calibration.
I'm certain that the vast majority will poo-poo my
assertions, but for the few who don't, feel free to ask any
questions you may have. Also, bear in mind that on several
hundred occasions, I've balanced tires that were previously
balanced on the computer, usually several times. Like I
said, I get zero come-backs.
I should mention at this point, I don't balance drive
wheels. (I find it more troublesome) I balance the rears or
fronts, as the case may be, then rotate them and use the
spinner again. This isn't necessary, simply easier, faster
and more accurate due to speed control. Some would argue
that it is less accurate due to axle and hub imperfection,
which is a somewhat worthy point. But you lose speed
control, something I consider very important. Besides, any
other type of balancer has no hub or flange centering
capability.
The only person I've met who has done half as many on-car
balances is my father. Even he never mastered the tuner and
strobe less approach. I didn't do this until I was 28. Pop
never used a spin balancer until he was 27. I'm pushing 58,
so I've been doing it 'my way' for 30 years. Prior to this,
I was using the tuner and/or strobe for 12 years. I'd have
no problem explaining their use, either.
So make me a punching bag, again, or ask to be
educated…
David Schaaf
Owner/Technician
Dave's Auto Repair
Elverta, California, USA