Build a sled/ box which the log sits in which can then run along the fence of your bandsaw (the base of the sled will obviously get cut along with the log but can normally be reused a few times if you have similar sized logs)
Hi Brian,have a look on youtube,build a saw mill sled for a bandsaw by Thom Stevens. https://WWW.youtube.com/watch?v=VOnZhVXogjs it will work for logs as well.He also has a second vid on an adjustable sled.