Valve travel of 1/32" or .032 should be more than sufficient for a
Gulbransen valve.  It sounds like you have replaced the existing wooden
valve buttons with a much thinner material.  It is difficult to re-leather
original valve buttons and not require paper spacers.  You may have to
add leather to the buttons to reduce the travel.  Excessive travel leads
to excessive air usage and makes for a noisy operation.   Be sure to
check for proper seating of the valve buttons as we explained in an
earlier posting.

Bob & Sonja Lemon¶
Lemon's Player Piano Service¶
Sacramento, CA