We found that Titebond III glue has enough flexibility to distort the round shape of the barrel during the high pressure stretch. Using Titebond Original wood glue seems to solve this problem. However, we have started adding rim reinforcement to the barrel for added strength. This process is a lot of extra work and adds weight to the finished drum. It is not clear whether it is needed, but we also like the extra wood that is available for forming the rim, allowing for a more tubby-shaped drum.