upright touchweight

[RicB]

Hi John

Sure its possible to increase friction and widen the difference between 
upweight and down weight. Your BW is pretty decent as it is... actually 
a tad on the heavy side yes ? 40-42.5 grams by your figures. Seems to me 
you'd want to introduce a little friction if you'd want to change 
anything at all here. You are looking at 5 to 7.5 grams of friction 
which is low in anyones book.... tho not necessarily to be viewed as a 
bad thing... taste thing to a significant degree. Check your hammer and 
whippen centers to see if you can get anything that way first. 
Otherwise... I haven't really thought so much about upright touchweight 
myself really. Has never seemed quite worth the cost of getting all that 
deep into it beyond a decent regulation. I'm sure there are several 
approaches to increasing friction in uprights tho... it will be 
interesting to follow the thread.

Cheers
RicB



    For example, a Samick upright, JS 115:

    Downweights 40-45gr
    Upweights 30gr
    Keyleads Bass 1 lead, 2” behind balance rail
    Mid 1 lead at back of key
    Treb 2 leads at back of key

    My biggest question: Is it possible to widen the difference between
    the DW
    and UW (friction), or do you just shoot for an acceptable Balance
    Weight?

    What do you do about the inertia of the keys? For feel, we should
    have more
    inertia in the bass than in the treble. It should be contiguous,
    therefore
    the butt springs would have to be adjusted after the keys are leaded.

    I’ve considered double-leading the key (front and rear) to increase
    inertia
    in the bass without affecting the static touchweight, but would that
    affect
    repetition speed?

    Many more thoughts and questions on the subject, but this would be a
    good
    beginning.

    Thanks.
    John Tonyan