I recommend you try gaffer tape instead of duct tape.
Advantages:
Remains flexible and removable forever.
Looks nicer, a cool matte black or manynother colors.
Where I get off making this recommendation:
I needed a light-excluding bellows for a photographic project. I made one using black illustration stock and gaffer tape. It worked extremely well on the first version and held up to hundreds of cycles of extension/compression. My application was sensitive to pinhole light leakage and there was none.
It would have lasted longer but that was the end of that project.
I recommend you try gaffer tape instead of duct tape.
Advantages:
Where I get off making this recommendation:
I needed a light-excluding bellows for a photographic project. I made one using black illustration stock and gaffer tape. It worked extremely well on the first version and held up to hundreds of cycles of extension/compression. My application was sensitive to pinhole light leakage and there was none.
It would have lasted longer but that was the end of that project.
My two cents. I love DIY stuff!