Joining breadboard to glued-up top
I am using old growth clear Douglas fir 1x6 T&G to make a table top- I would like to cover the end grains that show the T&G with 1x2 old growth clear Douglas Fir - I believe this material is at least 60 years old. Can I craft a mitered box frame around the glued-up T&G boards, and glue the frame around the entire top? Or will it expand/contract seasonally - this will be sewing table in a bedroom. If you think it will expand/contract, would it be less likely to do so with just breadboard on each of the glued-up 1x6 ends? I do have a pocket screw rig, but I have never crafted mortise and tenon, and hoped that the age and dry storage of the material might lessen the likelihood of a expansion/contraction problems. Thanks for your help!