Weight of fo in relation to wick size

[giedre11]

Don't know if this is a dumb question {hmm, probably is!} but since some fo's are "heavier" and you need to wick up on them...and you haven't tested a particular fo yet...well, if you poured up a liquid oz. of fo, and then weighed it, wouldn't it help you in your wick testing if you compared it {weight wise} to say a known heavy weight fo such as vanilla and started testing from there? I hope this makes sense.

[topofmurrayhill]

Don't know if this is a dumb question {hmm, probably is!} but since some fo's are "heavier" and you need to wick up on them...and you haven't tested a particular fo yet...well, if you poured up a liquid oz. of fo, and then weighed it, wouldn't it help you in your wick testing if you compared it {weight wise} to say a known heavy weight fo such as vanilla and started testing from there? I hope this makes sense.

Actually it's a really good question. I don't think anyone has done a study of it, but my impression is that you can't go by that.

The measurement you'd be making is the density of the FO, but you can actually look that up. Occasionally it's printed on the FO bottle, but otherwise it's on the MSDS sheet. The number is called specific gravity (SG). Greater than 1 is more dense than water (heavier in the test you proposed) and below 1 is lighter or less dense than water.

The problem is, there are definitely high density oils that can be a wick down and low density oils that can be a wick up. It doesn't correlate consistently and maybe not even very well.

What probably matters more is the viscosity, meaning how thick a consistency the oil has (like water versus honey). Unfortunately they don't give you that measurement and you can't really do it yourself.

Here's a perfect example. I tried 2 different viscosities of mineral oil in wax to see what would happen -- 70 and 200. The 70 burned fine. The 200 didn't burn well even when wicked up. However, 200 viscosity mineral oil is actually much lighter than the majority of FOs. The SG was 0.856 in this case.