Outdoor Fire Pit Project - Part 2

This is a continuation of the fire pit project.  This past week I visited some local brick yards to get the materials.  At two of three brickyards I was told that fire brick was not appropriate for an outdoor fire pit because it does not hold up to weather (rain, snow, freezing, etc.).  This is in conflict with what the plan I found on the internet said to use.  Also it is in conflict with the outdoor grill project in the Complete Guide to Home Masonry by Black & Decker book.  At one of the brick yards I was advised to use clay pavers for the project.  Clay pavers are fired at a very high temperature so they should hold up as well as fire brick to the temperatures.  After some thought, I decided that this was a good idea and it actually could simplify the whole project because instead of needing two courses (one on the inside in fire brick and a decorative course on the outside) I would only need a single course of bricks since the clay pavers would be both fire resistant and decorative all in one.  At one brick yard they also sold the Heat Stop 50 refractory motar dry mix in 50 lb. pale for $65 so I bought that.  The clay pavers were $0.78 each and I bought 72 of them planning for a stack height of 3 high with 18 bricks per level plus a whole extra level worth of bricks as spares.  I figured 18 by dividing the circumference by the 8 in. width of the bricks.  The bricks are 8 in. by 4 in. by 2.25 in.  After some playing with the bricks to determine the best look, we decided that a stack height of 4 would be the best, in the following configuration:

The top and bottom layers would be flat, while the middle two would be standing on their sides.  This provides a very nice look and also was the most desirable height.  We also thought about going with two layers on their sides with a single cap layer flat on top (a little too short), and three layers on their sides with a single cap layer flat on top (I thought this was too high).

Two of us then started setting the bricks.  I mixed 10 lbs. of the mortar per the instructions.  At first it went on fairly well, but toward the end it was not sticking to the bricks very well.  It turned out that the first bottom course needed 19 bricks (not the 18 that I planned for).  After mixing the second 10 lbs of mortar I was almost done with the bottom course.  The mortar joints were pretty thick in between the bricks because I did not cut them at all and they were laid in a circle around the fire pit perimeter with a tight joint on the inside but much wider on the outside.  It was about time to finish for the day after the second 10 lbs of mortar, but I wanted to finish the bottom so I decided to mix the next 10 lbs.  I mixed that a little wetter, which actually just made it harder to work with and did not make it dry any slower, so toward the end again it was very hard to work with.  With the third 10 lbs. of mortar I was able to finish the first layer and about 14 of the second layer.  The joints on the second layer were much thinner because the bricks are on their sides and the gap is not very large.  Also I determined that the second layer would take 20 bricks (same with the third).  Assuming the 4th takes 19 again like the first, the total bricks needed is 78 so I'm 6 short.  I also do not think the single 50 lb. pale of mortar is going to be enough, so I'll probably need to buy a second along with some more bricks this week.

Total time spent today for two people - 6 man hours