So, I looked at my Bandsaw mill ideas and realised I was over-engineering the key elements. So I started again, developing the architecture to use industrial linear bearings.
I’m posting my redesign thus far, so that the progress can be seen.
These images show a far from complete concept, but I hope show how my thinking has developed. This machine should be capable of milling 28″ diameter logs.
This image shows the bunk, bow and vertical slide. Industrial linear bearings are used to provide accurate movement.
Click the images to enlarge.
Take-up units as found in conveyor systems allow for band wheel tracking. They could also provide adjustment for blade tension. However, using these units for tensioning the blade would be crude. My plan is to add a hydraulic tensioner to this system once configuration for the machine as a whole is complete.
The vertical travel of the bow uses similar linear bearings to the longitudinal travel. The configuration shown here ensures that the bearings are taking compression forces only which will improve accuracy and life expectancy of the units. At this stage the bow is concept fitted only. When the design is completed, adequate gusseting will be incorporated to resist lateral and torsional loads upon the bow.
Again a concept view, rather than final design solution. However the linear rail system can be seen. The final iteration will include some strengthening and rail wipers to ensure the linear bearings are kept clean in use.