How can I fix a twisted audio tape?

Is it possible to untwist a four foot length of tape; the tape is not broken. I have manually smoothed out short portions of tape before, but I cannot budge this one. I have approximately 40 old tapes on which my late husband recorded some of his favorite (and mine, too) music, as well as visits, conversations, etc. with relavites, which I want to preserve for myself and my family after I am gone. Any suggestions are welcome!