Hi guys, I’ve been installing and sanding flooring for 12 years now. 5 of which has been through my own company. Every once and while I come across streaking and lines where the stain does not take the same.

Here is the sanding process I use
- 60 grit Big machine and edge to remove old stain and level
- puddy whole floor to fill cracks and seams
- 80 grit big machine and edge off puddy
- scrape and sand corners
- 100 grit buff entire floor with 6 disc sander.
- apply stain with buffer using a slice of carpet.

To me it looks as if it could be lines from the 6 disc sander. I’m new to this forum so I’m struggling to upload pictures. Any suggestions and help is greatly appreciated!

You may be able to tell what machine is making the lines and then find a solution. Usually lines are going to come from a machine like a drum sander which goes back and forth instead of around in circles like a rotary sander. Maybe the drum is not even with the floor because of something sticking to the wheels. This is only a beginning. A careful check ought to show the problem so you can fix it. Since you are the one operating the machines, you have the best chance for a solution.