Comment history

Fix-It Chick: How to make lime mortar

You cannot make hydrated lime without quicklime.
You get quicklime, add just 27% water by volume. The exothermic reaction creates heat it does not explode. The reaction takes up the water into the hydrate and because just enough water is added we end with a dry hydrate. So you have added h2o to Cao and you get ca(ho2) commonly known as Cacuim Hudroxide.

When you heat or burn limestone, chalk, shell, marble, all different forms of calcium. you drive off the calcium dioxide oxygen hydrogen etc, and create Quicklime.
Because energy cannot be destroyed the heat put in whilst burning off carbon dioxide it is stored in the quicklime. When you return water (ever heard of slaking your thirst) the quicklime releases it's stored energy , heat, an exothermic reaction.

Whilst making lime putty we actually add 300% water not 27% is means that the 27% is still taken up but we end up with a paste because we have added too much water to make a powder. Lime putty is what we add to sands to make a mortar.

So far we have replaced the oxygen and hydrogen back to the caluim. When we expose the mortar to atmousphere the lime takes in the missing carbon dioxide. Originally burned off. When that is done it becomes chalk limestone again,

So we have taken a lump of chalk to bits, added sand, with carbonisation we now have a lump of chalk combined with sand which is stronger than the the individual parts. Which were chalk, limestone etc and sand.

One last point, people are so pre-occupied by the danders of lime. Consider this. I for one would much rather handle lime lime putty and quicklime . Than your average househ

July 3, 2013 at 5:22 p.m. ( | suggest removal )

Fix-It Chick: How to make lime mortar

Disappointed to read such an ill informed piece. Hydrated lime is never as succeful as lime putty because of the lack of free water. Hydrated lime starts to carbonate the moment it is made. Therefore after 6 months you will have a bag of both hydrate and chalk or limestone. ( check the lime cycle somewhere.

Hydrated lime is already slaked quicklime. So your ideas of "cooking" has nothing to do with slaking and every thing to do with re-hydrating. Or addi g the free water found in lime putty.

It is obvious to me that you have never actually performed your method because hydrated lime will not creat an exothermic reaction (create heat).

If you have actually mistaken hydrated lime with Quicklime then your proportions are all wrong.

If this is so, what you are describing is a hot mix. Where, because quicklime will expand by three when slaked. You actually need 1:9 ratio of quicklime to agrigate.

July 1, 2013 at 3:23 p.m. ( | suggest removal )