hi!
what causes the timing to go out?
more generally-
how often should i expect to have to tune up a singer 401?
is there a point in an older mechanical sewing machine's life where it just ceases to work properly? i mean....if i use the machine well, take good care of it, have it tuned and serviced however often i am supposed to, i am wondering....do they wear out? slowly become less reliable and more prone to doing things like...sending their timing off?
thanks for your help, as always
aileen