Mold Clean Up and Repair

6. While the inside pass is being done, some one (or several people) can be cleaning the mold. 

NEVER use water on the mold. Brush the mold off using the stiff broom-brush in your bucket. 

If there is white cement specks still clinging that won't come off with the broom, use a scrubby (fibra) on those spots.  The mold is clean when all the cement is removed from the sheet metal, this includes white specks, etc.

After the cement is cleaned off, liberally apply a coat of burnt motor oil on the outside of the mold and along the angle iron edges.

There should be a rag with the oil for applying the oil.
Your fingers will be covered with oil before you are done.  To clean the oil off your hands, the best method is to use some of the sand and keep rubbing your hands in it. This will take off most of it and then water with dish soap should remove the rest.  

Check the mold sections carefully for missing pop-rivets. If there are any missing, replace them using the pop riviter. Set the finished mold aside for the next tank.

Second inside Pass

7.  Mix another 3 botes de arena, 1 bote de cemento and 1 1/4 botes de agua. Repeat the above procedure for the second pass but save back a little more than 1/2 bucket of mixed cement. 
The second inside pass is applied after at least a two hour break for breakfast.  I is put on very thin, a little wet depending on how dry the first pass is.  The danger is to wet the wall down too much or make it to thick.  This will cause the entire inside pass to crack, sink or fall down.  I speak from experience.  Keep it thin and the mix workable!

The second inside pass needs to "flow" on in a thin layer, filling in depressions and smoothing our the bumps.  The second inside pass will take only about 1 and one half buckets of mix.  You will need to use about one half bucket to slightly build up the lip area of the tank, being careful not to overload it! 

Using a wet Float you can smooth the tank walls before brushing them.  The photo above shows the inside before brushing. Look ahead to Day 4 to see the inside walls after smoothing and a light brushing. The smoother it is today the less work painting it tomorrow.