I did a rehab on a playset this weekend. The main swing beam wasn't long enough for 3 swings - so I bought a new 4x6 plank that's 12 feet long. Worked perfect. It came from HD and was treated - it was also very heavy and I had the sense it was wet, as I suppose some lumber still is when bought.
Then I used a paint gun to spray solid color stain over the whole playset. The stuff goes on exactly like paint.
Now that I'm done - I'm concerned that perhaps I just sealed up wet wood and perhaps I should have waited to spray stain it.