What do you do with tefillin that belonged to family members, that would probably be passul if check or the sofer won't correct them because the ktav yad is sooo tiny?

Is it fine to display them- like a museum would?

What do families to with used tefillin? I know some get to straps and get the batim redone, as long as the parshiyot are ok. What are the other options besides burial?

eta: as in belong to grandfather, g-grandfather, gg-grandfather, etc.

why would they "probably be passul?"

we "stupidly" had one of my great-grandfather's tefillin opened and checked. While the ktav yad was in a beautiful hand according to the sofer- the script was faded to brown. The size of the tefillin were the main issue because my sofrim aren't skilled to deal with tiny German tefillin (sometimes called travel tefillin).

I'm not sure what the problem is. It's passul if the ink oxidizes? Is that the pair you're looking to do something with?

What happened was, we thought it would be really great if one of the pairs were kosher, so we decided to get it checked.

I don't know if all sofrim agree regarding the wearing of the letters. the batim weren't in top condition, in any case. We may eventually just display them-- I was curious if there's any issues with that (I only bet that someone has a reason why it's in appropriate)

Display them; sure beats putting them in a hole in the ground.

Under normal circumstances, tefillin only need to be checked initially to ascertain that it is kosher - then chazakah takes over. Perhaps age is a mitigating factor (as would be mistreatment, like prolonged exposure to the sun or constant placing on wet hair), but if not, then they needn't have been opened in the first place!