*Specs: All Bass Sperzel tuners non-staggered posts:
There are NO staggered post Bass Sperzels available, they don't exist.
A Sperzel Bass tuner requires a .437" ( or 7/16" ) hole in the head stock for the tuners to fit...
If you are drilling your own holes, I usually find that the best results come from drilling with a high quality 7/16" Brad Point drill bit.
*!*!*Many popular Bass head stocks (including Fender) have a 9/16" hole.
Sperzels will NOT work with this type of Bass, unless it is doweled and re-drilled*!*!*
Sperzels with the #2B bass buttons will take up a minimum of approximately 1.3" of
space on a head stock before the buttons start to touch each other...
The Maximum thickness of a head stock can be .700" (approx 45/64" )
The Minimum thickness of a head stock can be .550" (Approx. 9/16")
Also, 2x2 and 4 in line sets can't fit a string larger
then .125" diameter through the tuner post...
5 string Bass sets are made to accommodate the larger low -B- strings.
Also, keep in mind that most bass strings become tapered at the end.
If needed Sperzel can custom drill to .145" max free of charge.
Please be aware that all of these measurements may slightly vary from key to key..
Drilling the set pins for Sperzel BASS tuners.
First thing you should know, is the instructions that came on the box of your Sperzel Bass tuners are incorrect.
They are actually the instructions for the Guitar sets.
Hopefully this problem will be changed in the future.
That being said, here are some tips for drilling the set pins:
In drilling the set pin holes I always use a drill bit that is close to the pin size, but a small amount larger
9/64" is just about .005" over the pin size.
This is needed for a little extra "play"...
Always making sure to drill exactly where the pin holes need to be is very critical.
Unfortunately the technique for doing this is rather difficult to explain with out the use of many photos along with a very detailed explanation.
Someday (when I have more time) I will try to document this process, and post it on this page.
If you are experienced at installing Sperzels, then you should be just fine...
However, IF you have any doubts in your abilities to install Sperzels PLEASE be sure to have them installed by a professional Luthier..
If done wrong (it's easier then you would think to screw this up) then it could seriously damage your instrument.