new to diy

[nedwood]

Just a quick question, when tweeking a flavour, if I want to add more flavour concentrate too it to I take the ml off the vg?

 

[Hoosier]

Maybe.

When I'm"tweaking" a juice, I just add and make a note of what I put in at the bottom of my notes of what is already in it.

When I'm changing the total flavoring % , and keeping the same total volume, VG and/or PG goes up/down in direct relation to the flavoring going down/up. Because it is a percentage thing. (fancy math speak there)

 

[nedwood]

Aha so say there's 15% flavouring and I added bits and it went to 17% id take 2% off the vg or 1% of both?

 

[IDJoel]

Depends on the base ot the flavor in question. The most common flavor base is PG. BUT there are flavors availible in a VG base (though not nearly as many as PG). And then there are the even less common "blends" that use a combination of PG AND VG (like One Stop DIY shop's flavor blends).
Each type, when added, will increase the total percentage of that base type. In other words:

• 15% PG based flavoring + 2% extra PG based flavoring = 17% total PG applied to your final PG/VG ratio. If my target ratio is 50%/50%; then I will still need to add 33% PG (17% +33% = 50%) + 50% VG

However, if I am using VG based flavors then is would look like:

• 15% VG based flavoring + 2% extra VG based flavoring = 17% total VG applied to your final PG/VG ratio. If my target ratio is 50%/50%; then I will still need to add 33% VG (17% +33% = 50%) + 50% PG

And I am using a mixed base flavor (like OSDIYS Blue Raspberry Slush which is 33%PG/67%VG) it will look like this:

• (33%PG @15% volume=4.95%PG)+(33%PG @2%volume=0.66%PG)=5.61% applied to total PG
  
• (67%VG @15% volume=10.05%VG)+(67%VG @2%volume=1.34%VG)=11.39%applied to total VG

But the short(er) answer to your question is yes; if I am adding PG It will reduce the VG percentage. If I am adding VG then it will reduce the PG percentage. This is regardless of where the PG and VG come from; flavor base, nicotine base, straight PG, or straight VG.

The PG/VG ratio is always going to equal 100%. So if one goes up the other goes down.