Well, since you asked...
That trick with the leaf springs sounds like a pretty clever idea to me. The
load that
bends a leaf spring has to overcome not only the designed-in stiffness of the
material,
but also the friction between the leaves. As static friction is, in nearly all
cases,
higher than kinetic friction (teflon being a notable exception), there is a
momentary
"stiction" as the sliding action at the leaf-leaf interface transitions from
the higher
initial friction value to the lower friction regime as the relative velocity of
the two
leaves increases. Greasing the leaves (and protecting them from contamination
w/the tape)
seems like it would do just as this old-time hot rodder said - allow the leaves
to work
more easily against each other, yielding a smoother suspension feel..
It's worth protecting leaf springs from dirt and grit in any case, to reduce
wear. I have
seen ads in "Classic & Sportscar", an excellent British classic car magazine
that I read
every month, for boots (made of leather, as I recall) that fit over leaf
springs for
protection against the elements. Something a bit more flexible and more "high
tech", such
as a rubber or neoprene-type material might work even better than a leather
boot or
electrical tape. There's a great spring refurb service idea here - recurve,
lubricate and
dip in a curing rubber to coat and protect the leaf group and keep the
lubricant in, dirt
out!
Gary McCormick
San Jose, CA
"Ofarrell, Fergus" wrote:
> ref: Gordon's message below
> Last weekend I was at the Pomona HotRod Swap Meet, (buy blemished Grant
> steering wheels for 1/2 price) and stopped next to a really sweet looking
> Ford T-bucket style roadster. The guy had a leaf spring looking arrangement
> running across the front from side to side. (rather than one on each side)
> In poaching the conversation/talk going on, someone asked him why the leafs
> were taped up with what looked like electrical tape / black duct tape.
> He said that an old street rodder (maybe he said dirt tracker) trick was to
> separate the leafs, and grease them up so they slid on each other easier,
> then put them back together, and tape the outside to keep the grease from
> leaking out (and feeling sticky and picking up dust). He said then you got
> the stiff (less bottom out) spring rate and ride height, but a smoother
> feel. The science makes sense to me but I'd be curious as to what others
> (Gary McCormick?) think of this concept. (bending springs the same way, but
> reduced frictional resistance on initial force application)
> BTW: this guy was old enough to know the tricks of this era, and while the
> rod was shiny, it wasn't a real modern rod, had '39 Ford front drums
> ________________
> From: "Gordon Glasgow" <gsglasgow@home.com>
> Subject: RE: Rear springs
> I haven't tried the 1600 springs yet (I've considered it) but I have run the
> comp springs for a long time and I assure you they are very stiff. I
> wouldn't run comp rears without also installing comp fronts. Some of the
> racers even said the comp rears were too stiff for racing purposes!
> Gordon Glasgow
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