Baldwin accu-hitch pins

Ron Nossaman RNossaman@KSCABLE.com
Sat, 19 Jan 2002 17:42:11 -0600


>
> Hi Ron
>   Ok I get this sort of but the place where I'm hung up is that as you start
> driving the strings down on the hitch your bearing increases as does the
> amount the board is compressing as you go. Just like in pitch raising. So how
> do you know when enough is enough and when do you know that there is enough
> ,of the desired deflections so often discussed. Meaning a 1 to 11/2 degree
> angle of deflection depending where in the scale we are talking about.


Ok, I get it. How can you tell where to set the plate and aliquot height with a
more "usual" system? If you can set the plate and aliquot height to produce the
bearing you want in a conventional system when the strings go on, you can do
exactly the same thing with the vertical hitch pins. When you are strung and at
tension and start to set the bearing, you can drive all the sections down to
almost where you had anticipated they would finally be to pre load the board.
You know about where that final height is expected to be because you set the
plate height to put them there, like you would with aliquots. Then, unlike with
the aliquot system, you can do an adjustment pass for the final height and put
them just where you want them. There is already enough load on the board at
that time to not make much difference in deflection from small bearing changes
in sections. Spot check after, and tweak sections as necessary. I start in the
low tenor and work toward the treble, and haven't had any problems at all with
the system. It might take two passes to get them where you want them, but it
goes quickly.

>
>  Once again how could a person possibly know what the final position is?


Just like you know that the plate and aliquot setting you decided on will
produce the bearing you want. It's the same process.



>
>    My answer so far is that you can't. Its more of a guesstimate than I'm
> willing to make until somebody can give me some clarification.
>   Does this help to see my angle of deflection!!!!!!!


Why would anyone set a bearing angle on an unloaded board without compensating
for expected deflection, with either vertical pins or aliquots? Of course you
anticipate the deflection when you set bridge/plate height! Who said you
didn't? Maybe I didn't say it so pretty good. When establishing bearing before
stringing, you do just what you always do. You either pre load the board, or
have a pretty darn good idea how far it is going to deflect under load, and set
bridge/plate height to accommodate it. Vertical hitch pins don't change that
process one bit. The only difference is that your back scale termination that
determines the final loaded bearing angle is not the top of an aliquot, but a
spot about 4mm up the hitch pin. The vertical hitch system isn't something
magic that fixes any random thing that might be done wrong in the setup. You
still have to pay attention and set the thing up correctly.

Ron N


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