I’m a novice woodworker. I’m helping my friend build a desk and to save some money, we went with “1 in. x 6 in Premium Kiln-Dried Square Edge Whitewood Common Board” from Home Depot.
Once we got to sanding, we used a random orbital sander starting with 60 grit then to 80 then to 100 then to 120 then to 150. For some reason the wood ended up being smooth in its overall texture but very bumpy in accordance with the grain pattern. The darker parts of the grain pattern seemed to not sand down as much as the lighter parts so the bumpiness seemed to be caused by that. We tried using less pressure when sanding and I also upgraded from a Ryobi to a Dewalt random orbital sander halfway through our sanding and it seemed to help but it also seems like it’s more a problem with the wood.
What did we do wrong?