Wizcraft thanks so much for the detailed info...
It has made me think through this in other ways.
The wallets that I sew have the interiors pieces that can be 4 to 6 oz...that have to be sewed before getting to the end process of sewing 14 oz of leather. From your response, its not just max thickness of leather, but also consider how thin the machine has to sew as well.
Is the CB3200 still a machine I should be looking at for 138 thread on 4 oz leather interiors?
Is there another cylinder that would be better for small goods like wallets, journals, belts...and allow me to try some bags in the future.
Even with wallets, I can sort of see the advantage of a cylinder with sewing a bifold. When I hand stitch a bifold, I hang the wallet off the table to edge groove and punch holes when working close to the spine.
I am told you can still machine sew Bifolds with a flat table machine...but a cylinder seems like it would be easier.