While most closed-cell spray foams will be above 6.0 per inch, open-cell is much lower at 3.6 to 3.8 per inch range. Open-cell will expand as soon as its applied, making it the perfect foam for ...

Half a gallon of wood glue, a pile of random, scattered resistors, or in [Ken]’s case, closed-cell silicone foam. Wanting to avoid this situation he set about trying to make his own silicone ...