Raw Materials: 6 bags of .5 cu ft of drainage gravel (Lowes)
42 Retaining Wall Blocks (Home Depot)
Angle Grinder with concrete-ready blade (only needed if you get blocks that do not have two level faces)
Step 1: Place 14 Blocks in Circle
I would also like to note at this point that you could use any number of blocks for different size fire pits and 12 would actually be the easiest to set up because the angles work the best. I chose 14 simply because I liked that size.
Step 2: Remove Blocks, Dig, and Lay Gravel
Dig a hole in the center of the pit about 20 in deep and 15 inches in diameter. Fill this with gravel for drainage.
Note: My pit was located in an area with wood chips so the area already drained well, hence less drainage rocks were needed. If you have clay soil I would advise following the instructions from this old house on the trench/ hole depths. Or you can use your own discretion.
Step 3: Remove "Tags" With Angle Grinder
Yes it makes life easier if you use blocks that do not have these "tags", but in order to have this color at from my local Home Depot it was my only option.
So to get rid of the tags I cut across with the angle grinder then "scraped" any remaining part that prohibited the face from being perfectly level.
Step 4: Lay Blocks on Gravel Ring
Step 5: Add Remaining Gravel
The one thing I was worried about was cracking of the blocks. I have had 3 fires in the pit so far without any cracking. I will post an update if the blocks do ever crack. Overall for a little more work I saved at least $300 because a similar sized kit would have cost me at least $400. The kits do have a steel ring which helps form a perfect circle, but I was told by a local stone retailer that it was not necessary in order to protect the blocks from the fire.