I'm building a 17'x23' paver patio and have finished the 6" compacted crushed stone base. My question relates to flatness of this layer. While I maintain an overall pitch away from the house, does the crushed stone base need to be perfectly flat before the slag sand/stone dust goes down? In other words, can one area have 1.5" of stone dust, while another may only have 3/4"? The overall slag sand layer will be perfectly flat and pitched, but does it need to be a uniform thickness throughout?

I ask because getting the crushed stone base perfectly flat has been a chore, and I am still left with small valleys and hills. Albeit the variance is probably 1/2" on average, but I want to ensure this won't affect the final [seasoned] level of the patio.

Thanks for the guidance with this!

1/2" is not worth fretting over. 1/4" would have been better but a lot more work. There is different densities for the crushed stone and the sand. The important thing is getting the compaction in the crushed stone with proper moisture content for maximum compaction. The sand is just a leveling layer to make up the unevenness of the base, is easier to work to finish subgrade, but needs moisture and compaction also. Good luck. JMHO Aloha