Hi, thought I'd share a bit of work I did recently around calculating the viscosity of PG/VG mixes.
Some background: I've been using a 60PG/40VG mix for some time and decided to go for more VG (more vapour / less
throat hit) and mixed up a 50/50 mix. I found that the solution was far too thick (viscous) to wick decently in my
rta (fogger v4/5). I needed to add some water (distilled water) (other options are PGA/Vodka but I haven't explored those - too expensive).
I researched viscosity of PG and VG, including dilutions of VG with water. I then
came across a formula for determining the viscosity of solution using the viscosity of each component. Using this I created
a spreadsheet that one can use to determine the correct amount of water to add in order to obtain the desired viscosity. In my case I aim for that of a 60PG/40VG solution.
To use the spreadsheet, change the values of B2 and B7. The current spreadsheet is set for 12% DW (distilled water) and 70%. The calculations are based also on the excellent spreadsheet I found on ECF:
ejuce_calculatorv13.xls (sticky in this forum).
I have mixed up a batch as per the spreadsheet and it seems to be right - I'm getting decent wicking and no leaking with a 70% (+12% DW) mix as per the values in the 'sheet.
Anyway, enjoy. I hope someone finds this useful.