Grain orientation of flooring

[JamieK]

Hey guys, I'm milling my first flooring on my woodmaster and just was wondering if the grain orientation of the lumber is critical or not. My thoughts are that if there is any cupping of the boards would it be better for them to be cup up or cup down??

[longtime lurker]

Biggest thing with flooring is uniformity of moisture throughout the feedstock. It needs to be properly dry throughout the piece with little or no gradient and at or around the EMC of the target construction site.

If you can get that right the timber is going to be pretty much stable and cup up or cup down going into the moulder won't matter because what comes out will lay flat and stay flat.

I normally feed cup down because it's easier, but I'm OCD with my setup and my finished product is reversible and can be laid either way up and the tongue and groove will line up regardless 

[JamieK]

Excellent, i was wondering if I was probably over thinking it. Thank you for your reply 

[scsmith42]

Adding to LL's sage advice, we select the "show side" based upon whichever face looks best.

[burdman_22]

I hope you update this with some pictures and advice/mistakes. I'm building a solar kiln next weekend to finish drying my oak and sycamore, then buying a woodmaster to make some flooring out of it. Would love any helpful information prior to learning from experience.

[firefighter ontheside]

This is my topic I started a few years ago about the flooring I made and put in my master bedroom.  There is lots of good info I receieved from various folks about the process of making flooring.  I did not pay any attention to grain orientation.  My wood was dried to about 7%.  I chose which side to use based on quality of side, knots etc.  I jointed one side flat and then planed to 3/4" before I chose which side to be the top.  I have 2", 3" and 4" boards and they are all still flat.  I did not t&g the ends.
https://forestryforum.com/board/index.php?topic=116781.0