it can be done with only cement but then not much water can be added. I gave too much water into it.
if the concrete diminishes due to evaporating water after some days I can add a layer with better made concrete to stiffen the bad construction. So it can be reinforced.
You took pure cement. Cement is the glue between the grains of sand. Used pure it doesn't get any strength at all. Remove it or it will turn into fine dust over time. Don't just pour something over it.
If you want such a thin layer of concrete, or in your case, mortar, to have some structural strengt, you should embed a kind of steel net into it.
Concrete is a mix of cement, sand and small stones, mortar only cement with sand. The sand has to be washed, so it doesn't contain any dust.
For your task it would be better to get some ready mixed repair mortar, which contains additives to improve hardening and elasicity. A beginners mistake is usually to use too much water. Read the instructions and do not think you know better.
PS cement based materials reach their basic strength after 30 days. They have to be keept damp for about 3 days, but not with water on top.
Concrete get's stronger over the years, think in decades and centuries. That is why so many Roman monuments are still there today and it is incredible expensive to remove old bunkers from WW2.
If you want such a thin layer of concrete, or in your case, mortar, to have some structural strengt, you should embed a kind of steel net into it.
Concrete is a mix of cement, sand and small stones, mortar only cement with sand. The sand has to be washed, so it doesn't contain any dust.
For your task it would be better to get some ready mixed repair mortar, which contains additives to improve hardening and elasicity. A beginners mistake is usually to use too much water. Read the instructions and do not think you know better.
PS cement based materials reach their basic strength after 30 days. They have to be keept damp for about 3 days, but not with water on top.
Concrete get's stronger over the years, think in decades and centuries. That is why so many Roman monuments are still there today and it is incredible expensive to remove old bunkers from WW2.
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yes, just removing the bad try.
The cardboard withstood well the mistreatment.
Next try will be better
The cardboard withstood well the mistreatment.
Next try will be better
loudspeaker with aluminium foil covered, diy whizzer full alu foil, faraday ring on pole piece, double magnet added
For squeezing out the cleanest sound out of a fullrange driver added damping to the basket facing the paper cone (white foam).
Here some report on optimizing the diy full metal whizzer / double cone:
Here some report on optimizing the diy full metal whizzer / double cone:
update for diy full alu whizzer making:
had a perfect result minimizing resonances of the full alu whizzer with three more cuts and filled the gap with glue
Works nice!
had a perfect result minimizing resonances of the full alu whizzer with three more cuts and filled the gap with glue
Works nice!