Please read before diagnosing... I have watched so many instructional videos, read so many threads and magazine articles, and continue to experience...
If I'm understanding correctly... In the case of the OP's design, the metal sleeve fits snugly inside the wooden 'jacket'... Without any adhesive at...
My mother recently progressed to needing a ramp on concrete steps at their house and went with the aluminum approach and has been very happy with it....