Drove 40 miles to shoot a lighthouse in Erie and forgot the take-up spool, took 3 weeks to figure out the fix
My Pentax K1000 kept jamming after every 4 or 5 frames and I blamed the shutter, the film, the lab, everything except the spool I left on my dresser, then a guy at a camera shop in Cleveland said to just cut a plastic pencil to fit the slot and it worked on the first try.