Con P. Seitl wrote:
>
> Tony Clark wrote:
> >
> > Someone wonders:
> > > How is it that it takes two hefty steel rods to turn the collar,
> > but the
> > > whole thing stays adjusted for years with one large setscrew?
> >
> > One big ol' cup point setscrew "machines" it's way into the bar and
> > will hold more torque than you can apply with one hand; my doors have
> > 2 set screws on each collar. It takes two bars 'cause you have to
> > "crank" with one to bring the next hole socket into view so you can
> > continue "cranking" with bar #2.
> > The 3/4" inch shaft is solid from one end to the other, a miss-match
> > in spring tension between the two springs is of no real consequence
> > in lifting the door; just in equalizing the load on the springs.
> .
> If I could clarify a point, the 3/4" shaft is not "solid" from one end
> to the other, but is actually "hollow". I think what is being tried to
> convey is the fact that the shaft is but one single length, not two. And
> the screws holding the end drum in place actually dimple the tube,
> creating a little 'cup' if you will, for the screw to rest in. Another
> point to mention is, DO NOT screw these two screws in until they are
> flush with the drum. Doing so will make the screw pierce the tube,
> resulting in a weakend tube. Further adjustment down the road may very
> well put the screws in another position, and if the same piercing method
> applied, you will have effectively cut your tube in half. Seen it done.
> Had too replace a fellows tube about 4 years ago because of this. It let
> go in the middle of the night when nobody was around and it also did a
> job on his top section of door. I'm not a professional, but I've
> installed 5 doors last summer as part of contract work, as well as
> adjusted my own! As I said before, " Don't make a 911 call of yourself!"
> Regards, Con.......
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