Martin did not use adjustable truss rods until the mid 80"s, but they did have some type of neck reinforcement. Gibson's have had adjustable truss rods since the 50's at least, probably long before that.
Most of the inexpensive guitars in the 50's and 60's had a steel reinforced neck, and had a sticker that said "Steel Reinforced Neck" where you would expect to find a truss rod cover. I'm surprised your Kay doesn't have one.
__________________
Rodger Knox, PE
1917 Martin 0-28
1956 Gibson J-50
et al
|