Thank you @Graham
I had thought of a linear stage for industrial applications but tried with the gear I already have. Not sure how they handle load in a vertical setup.
I usually do that too, but the canon 100mm macro, even though there is a tripod collar for it, has a polycarbon housing and I’m a bit reluctant to tighten the collar too much or glue the adapter ring to the lens body, How do you mount your lens?
The overall goal in building this rig was to use basic materials that could be mounted with basic skills. Using black MDF would have been my preferred solution, but the shop had none, but had a scrap peace of bamboo that was just big enough.