Outdoor Fire Pit Project - Part 3

This is a continuation of the outdoor fire pit project. On September 27 I completed the project.  I had to buy more bricks and more mortar to complete it.  We ran out of the 50 lb. pale of mortar toward the end of the top row.  I had bought what I thought was another 50 lb. pale of the dry mix Heat Stop 50 refractory mortar.  When I opened the pale it was actually a ready mixed version.  With the end in site, and this mortar being my only option, I decided to give it a try.  First of all it was ready mixed, but there was a lot of unmixed standing liquid in the pale.  I wasn't sure if it should be mixed in or not.  I partially mixed it in before proceeding.  I later learned that it was supposed to be thoroughly mixed in.  The mortar was a little easier to work with than the dry mix and did not dry out as quickly.  We finished the project.  Later that night I noticed that the ready mix mortar was not hard yet while the dry mix was already hardened.  I wasn't sure what to make of that.  The next morning it still was not dry.  Further reading on the pale of the ready mix mortar revealed that it was for interior applications only and is water soluble even after it dries.  After a week, the mortar was still not hard (it had rained a couple of times in that period).  I called the place where I bought it and they did not know what the consequence of using the interior only mortar in an exterior application would be.  I'm pretty certain based on my experience that if it is exposed to any moisture it will start to soften and dissolve.  I further tested this theory by using some of the ready mix on my metal casting furnace and it hardened beautifully.  Luckily because the mortar never hardened it was not a problem to remove the bricks (probably about 12) that were set with it and scrape off the mortar.  Moral of the story is to make sure they give you the right kind of refractory mortar - the ready mix and dry mix cost the same and come in basically the same size pale.

Total time spent on this last stage was 4 man hours.  Total time spent removing the bad mortar and bricks was 2 hours.

One more note was that I had to cut a few bricks.  I didn't invest in any special equipment or saws.  I used the chisel side of the brick layers hammer to score around the bricks and then break them off.  It worked okay, and I got reasonable results.  A real chisel probably would have worked better.  If I had a lot of bricks to cut, I would definitely get some type of saw or other specialized tool to do the job.

Here are some pictures of the finished fire pit before some of the top layer bricks were removed.