Those who splice their film with tape know the air bubbles that occasionally gather under the adhesive film. From Würker (and later Wittner) there was the practical tape roller with which this air could be removed. Splices processed in this way are less visible and audible.
Today, these rollers are hard to find and often very expensive. What helps: Build one yourself! A capstan drive pressure roll from the craft box and an old spoon (for a handy, sturdy handle) were all that was needed alongside a hole, bolts and nuts.
Recommended for imitation!