Re: tension shackles

[Tom Mandera <tsm1@domain.elided>]

On Sun, 13 Dec 1998, Daniel Nees wrote:

> I'm trying to picture this... Do you mean a shackle on each end of the
> spring? If you do then wouldn't the shackles then want to pivot
> backwards like a reverse shackle? Not that there is anything wrong with
> that, but; isn't the point more for longer travel?

Yes, a tension style shackle on both ends.. but you're right.. it would 
be better for them to rock *rearwards*.. though not important for 
discussion of the *concept*.. 

Wait.. actually, it wouldn't matter *at all* which direction the shackles 
pivot.. since the axle would not be able to move on a bump.. unlike the 
stock front suspension, which, when the axle goes up, it also goes 
forward because of the single forward shackle, this wouldn't be the 
case.  Recall that I"m talking about a 4-link locating system that would 
"lock" the rear axle into the arc that *I* define through the 4-link 
lengths n' such.  Thus, the shackles have NO relation to *where* in the 
wheel well the axle is.. it's this relationship between axle location and 
shackles that makes using a 4-link and a single shackle a bad thing, 
since you introduce a "bind" when the 4-link located axle fights with 
where the spring and shackles wants it to be.

Thus, I don't think the direction of the shackles' rotation would matter 
much for ride quality, etc.. the shackles would essentially be 
"free-floating" and only need to move when the spring compresses or 
droops.. and then *both* ends of the spring would move or both shackles 
would move outward or inward the same amount.

Of course, I'm now reminded why I didn't want the shackles to move the 
same direction.. the spring would have to pass *through* the shackle 
mount point.. oops.

So maybe.. one tension and one compression shackle.. to allow the same 
type of movement.. 

Hmm.. might need to make a model of this one!

>    How about a setup like a buggy spring concept, but; where you would
> have a shackle on the front that lays flat on the frame rail when not in
> use, but droops down when more droop is needed. I think the buggy spring
> would be better but this idea would be along that line.

Glenn Wakefield's "missing link" setup!  But again.. not so simple with 
the outboard mounted springs.. hmmm..

-Tom