Specific Gravity in DIY--How important is it? Does it really matter?

[IDJoel]

Of course there will be less used in pg/vg when using an already mixed base as the weight is different than when mixing all 3 individually. I compensated for this when I mix by volume by calculating my own values in ml. The calculator value for ml does not change in the online calculator however and that (to me) only adds to the confusion.

That is very true... and what leads to so many questions about using premixed "base" (PG/VG, or PG/VG/nic), as they can be used with any given calculator.

As you are finding out; many free online calculators do not have this extended capability.

The only one that does (that I am aware of) is ELR's. When creating a recipe, you start out by seeing a screen that looks like this:

Note the uncheck box near the bottom (red arrow). If, you check that, the screen changes to this:

This, now allows the user to input the specific PG, VG, and nicotine values, of your premade base. This should(?) correct the generated weights provided by the recipe. (Again; I haven't personally used it. So, I can't speak with any first hand experience.)

One can similarly edit/modify, any other publicly posted recipe on ELR, as well.

 

[Sugar_and_Spice]

That is very true... and what leads to so many questions about using premixed "base" (PG/VG, or PG/VG/nic), as they can be used with any given calculator.

As you are finding out; many free online calculators do not have this extended capability.

The only one that does (that I am aware of) is ELR's. When creating a recipe, you start out by seeing a screen that looks like this:
View attachment 798021

Note the uncheck box near the bottom (red arrow). If, you check that, the screen changes to this:
View attachment 798023

This, now allows the user to input the specific PG, VG, and nicotine values, of your premade base. This should(?) correct the generated weights provided by the recipe. (Again; I haven't personally used it. So, I can't speak with any first hand experience.)

One can similarly edit/modify, any other publicly posted recipe on ELR, as well.

Yes and thank you. That is the one I am using and by just clicking that one box changes the recipe in weight from total grams(nic,pg,vg) = 31.67 to when I clicked the box =28.65.(Using a 100ml bottle) But the total of ml is not changed in the ml column. And the totals for % stay the same also.

 

[IDJoel]

When it is visible to the naked eye in a 30 ml bottle it is more than just a few hundreds of a gram off. Can scales really be that far out, even when they are calibrated?

Once I had the correct S.G. values entered into my calculator; I no longer could detect any difference (by eye, or by taste) in mixing methods.

As for calibration... after I learned how much tolerance ("acceptable" variation) was permitted for cheap(er) calibration weights (the kind some include with our cheaper scales), I gave up on calibrating. Same for using coins, or other "in home" substitute weights.

I made a segregate weight, out of a paper clamp and a scrap of paper, to weigh 10.00g, that weighed the same on both my DIY scale and also my more precise (gun) powder scale. Primarily for use as a temporary weight to make registering those pesky 1-2 drop additions. As long as that remains consistent (mixing session to mixing session) I choose not to worry about calibrating.

If/when the time comes, that there is an unacceptable (to me) difference, then I will have to figure something out.

@IDJoel
I was in the process of making screen shots when my wifi went out. Had to restart my computer and lost it.

No worries! I think we are both on the same page now. I appreciate you trying!!

And, just a heads up; I need to get some supper, and run a couple of quick errands before it gets any later. So, I am not abandoning the discussion. I will check back in later this evening.

 

[Sugar_and_Spice]

We actually used to see Recipes a lot in this Format. And that was when people gave their Recipes in Percentages.

Because Percentages are another Unit Less Measurement. Just a Ratio of a Part divided by the Whole.

---

Yeah... Better we Don't mention Measuring by Drops. Because we All know what well happen if we do.

LOL

Well, guess I will be the one to mention drops. In the calculator they are way more accurate and closer to being equal to a regular volume mix in terms of numbers. And drops are very necessary when mixing test amounts to reach the requirement of the recipes. Even some flavors are now being formulated that require only 1 to 2 drops for a 10ml bottle(now that is concentrated) so drops are essential to mixing no matter if some members get their panties in a bunch or not. LOL

 

[zoiDman]

Well, guess I will be the one to mention drops. In the calculator they are way more accurate and closer to being equal to a regular volume mix in terms of numbers. And drops are very necessary when mixing test amounts to reach the requirement of the recipes. Even some flavors are now being formulated that require only 1 to 2 drops for a 10ml bottle(now that is concentrated) so drops are essential to mixing no matter if some members get their panties in a bunch or not. LOL

Oh Man... Oh Man Oh Man Oh Man.

I can Almost Hear the Drop Haters Now. You Can't Do That! It's Not Accurate! You'll Never be able to Share a Recipe Again!

LOL

 

[Sugar_and_Spice]

Oh Man... Oh Man Oh Man Oh Man.

I can Almost Hear the Drop Haters Now. You Can't Do That! It's Not Accurate! You'll Never be able to Share a Recipe Again!

LOL

That is fine. My recipes probably are not liked by many anyways and are boring to most. That is why I rarely post one. LOL

 

[AttyPops]

Neat thread. I learned a lot.
Seems like weight (since it requires SG cals factored in) would be fraught with peril. Concentrations are by volume (per ml) anyway.
Chromebooks don't like wifi outages.

You guys don't want to know how I mix my juice....

 

[Sugar_and_Spice]

Neat thread. I learned a lot.
Seems like weight (since it requires SG cals factored in) would be fraught with peril. Concentrations are by volume (per ml) anyway.
Chromebooks don't like wifi outages.

You guys don't want to know how I mix my juice....

Hi Atty, You are welcome at any time to post whatever DIY related tidbits that you want. (And almost anything else you see fit-- LOL) To date ---you are correct in all of your conclusions(except the one in how you mix.)
Good to see you out and about.

 

[zoiDman]

Neat thread. I learned a lot.
Seems like weight (since it requires SG cals factored in) would be fraught with peril. Concentrations are by volume (per ml) anyway.
Chromebooks don't like wifi outages.

You guys don't want to know how I mix my juice....

I'm Not sure I would use the phrase "fraught with peril". It's kinda like Most things in life, there is a Procedure to it.

You have to consider also what is Going to happen if say you used a Specific Gravity of 1.0 for all your Ingredients.
The Flavoring/Sweetener would be pretty much right on the Money. But Nicotine Level and the PG to VG Ratio would be a Little off.

I question how much Worse that would be from the Stated Numbers that is on the Average Bottle of Retail e-Liquid? Or whether the Average Vaper could even tell the Difference?

 

[AttyPops]

except the one in how you mix.

Let's just say I'm not picky.

I usually vape unflavored anyway. So as long as I'm relatively close on nic ratio, meh.

But if I had a few favorite recipes, I'd want to be able to recreate them accurately.

 

[Sugar_and_Spice]

I'm Not sure I would use the phrase "fraught with peril". It's kinda like Most things in life, there is a Procedure to it.

You have to consider also what is Going to happen if say you used a Specific Gravity of 1.0 for all your Ingredients.
The Flavoring/Sweetener would be pretty much right on the Money. But Nicotine Level and the PG to VG Ratio would be a Little off.

I question how much Worse that would be from the Stated Numbers that is on the Average Bottle of Retail e-Liquid? Or whether the Average Vaper could even tell the Difference?

Actually, they probably would not be able to tell the difference....but that brings me back to my recipes not tasting the same.

It has been a while since I have tried to mix with weight so I will try again-maybe over the weekend. When I tried before I mixed the same recipe several times and still ended up with less actual ml in the bottle than when I used volume(ml) mixing. And back then I did not use any premade base. They also did not taste the same. I can't remember which free online calculator I used or if I used the excel spreadsheet. (which in itself may be the problem).

 

[AttyPops]

I'm Not sure I would use the phrase "fraught with peril". It's kinda like Most things in life, there is a Procedure to it.

You have to consider also what is Going to happen if say you used a Specific Gravity of 1.0 for all your Ingredients.
The Flavoring/Sweetener would be pretty much right on the Money. But Nicotine Level and the PG to VG Ratio would be a Little off.

I question how much Worse that would be from the Stated Numbers that is on the Average Bottle of Retail e-Liquid? Or whether the Average Vaper could even tell the Difference?

Well, since S&S's results were off, we can conclude that her vendor didn't cut her VG with water... Most of the other things flavoring and PG, are near 1.0 so unless the flavoring is really really strong I wouldn't think it won't throw it off too awful much. And who knows the SG of each and every flavor? That's the peril part. The flavoring, IMO. Some are water, some are PG and some may even have alcohol.

Then there's viscosity....but I digress, as that's more of a wicking issue.

 

[zoiDman]

Actually, they probably would not be able to tell the difference....but that brings me back to my recipes not tasting the same.

It has been a while since I have tried to mix with weight so I will try again-maybe over the weekend. When I tried before I mixed the same recipe several times and still ended up with less actual ml in the bottle than when I used volume(ml) mixing. And back then I did not use any premade base. They also did not taste the same. I can't remember which free online calculator I used or if I used the excel spreadsheet. (which in itself may be the problem).

I'd give Mixing by Weight another Whirl.

Could be that it was the Calculator giving you some Funky Results? Or Maybe your Scale isn't doing Exactly what it Should? Or it could be the DIY Gods were just Cranky that Day? And sent you some Bad Mojo.

One thing I would do is get out a Syringe and Weigh some Water. If your Scale is Kosher, then you should be getting 1g per ml for Any amount you weigh.

 

[zoiDman]

Well, since S&S's results were off, we can conclude that her vendor didn't cut her VG with water... Most of the other things flavoring and PG, are near 1.0 so unless the flavoring is really really strong I wouldn't think it won't throw it off too awful much. And who knows the SG of each and every flavor? That's the peril part. The flavoring, IMO. Some are water, some are PG and some may even have alcohol.

Then there's viscosity....but I digress, as that's more of a wicking issue.

Yeah... When it comes to Apparent Specific Gravity, they only Real odd man out is the VG. All the Rest are basically hovering around 1g/ml.

Specific Gravity

100mg/ml is a Tad Heavy. But for what Most people Vape, they use Very Little of it. So the Relative Error is Very Small

 

[Sugar_and_Spice]

That is very true... and what leads to so many questions about using premixed "base" (PG/VG, or PG/VG/nic), as they can be used with any given calculator.

As you are finding out; many free online calculators do not have this extended capability.

The only one that does (that I am aware of) is ELR's. When creating a recipe, you start out by seeing a screen that looks like this:
View attachment 798021

Note the uncheck box near the bottom (red arrow). If, you check that, the screen changes to this:
View attachment 798023

This, now allows the user to input the specific PG, VG, and nicotine values, of your premade base. This should(?) correct the generated weights provided by the recipe. (Again; I haven't personally used it. So, I can't speak with any first hand experience.)

One can similarly edit/modify, any other publicly posted recipe on ELR, as well.

There is also a minor problem in the way it is presented in the recipe when using the vape ready Nicotine base made variable. The calculations do read the desired nic strength for the calculation but if you don't change the "nicotine strength" to match the 'desired strength' it reads in the recipe as
Nicotine juice 100 mg (100% PG) and instead of Nicotine juice 6 mg (100% PG). If you are not sharing or posting this recipe anywhere it makes no difference what it reads as the calculation is the same result. Can be a little confusing until you figure out how to fix it.

 

[IDJoel]

One thing I would do is get out a Syringe and Weigh some Water. If your Scale is Kosher, then you should be getting 1g per ml for Any amount you weigh.

I, personally, would qualify that as: "to within 5%." As that is acceptable tolerance for syringes (larger than 0.5mL) per ISO 7886-1 specifications.

(Before anyone gets the idea I am bashing syringes; I am not. Scales, too, have acceptable tolerances, set by the manufacture and dictated by its intended use. I make NO assertion that one method is any more accurate, than the other. Except Drops.... they just SUCK! (just kidding!))

Yeah... When it comes to Apparent Specific Gravity, they only Real odd man out is the VG. All the Rest are basically hovering around 1g/ml.

I would also include nicotine concentrates in VG, and partial-VG, to the list (though it is again the VG that is causing the increased variance). Especially, for those using lower (<72mL/mg; including premixed "bases") nicotine concentrations. And, they will likely have to add more total volume, to reach their preferred nicotine target levels.

 

[IDJoel]

but if you don't change the "nicotine strength" to match the 'desired strength' it reads in the recipe as
Nicotine juice 100 mg (100% PG) and instead of Nicotine juice 6 mg (100% PG).

I am thinking you are referring to this line (highlighted yellow):

If that is the line in question; then it should be set to the nicotine value of whatever your premixed base is mixed at (not "desired/final" strength). Note that the "Desired Strength" line (red arrow) is now greyed out, and locked? that is because your final nicotine strength is at the mercy of the other ingredients (flavor concentrates) you add.

Does that make sense?

 

[Sugar_and_Spice]

I am thinking you are referring to this line (highlighted yellow):
View attachment 798065
If that is the line in question; then it should be set to the nicotine value of whatever your premixed base is mixed at (not "desired/final" strength). Note that the "Desired Strength" line (red arrow) is now greyed out, and locked? that is because your final nicotine strength is at the mercy of the other ingredients (flavor concentrates) you add.

Does that make sense?

Well, yes, we are in agreement with that. It assumes whatever value that was already input in that area to use for the ready made base. I was referring to how the recipe would read to human eyes. The nic strength is also computed and placed below the listed recipe(scroll down) and gives the strength of the final mix as 5.5mg. From what I can tell the only value that those columns below the Max VG box is used for is to list how humans read it in the final recipe as those values are not used in the calculations to produce the mg's needed. BUT is used to calculate the final strength strength used in the final recipe. You will find that by scrolling down the page.


eta
this can be tested by inputting 'the nicotine strength' to 100 and then looking at the final recipe by scrolling down the page. Notice the differences between when you change that variable. When you input 6mg it calculates the final mix strength as 5.5 mg, but if that variable is not changed and remains at 100 it calculated the final strength in the recipe as 91mg/ml.

Like I said ---if not sharing that recipe with anyone else, and you understand what it is doing then it makes no difference. But if sharing, you want others to read the correct mg/ml in the final recipe.
We probably are saying the same thing just in a different way??
?

 

[IDJoel]

From what I can tell the only value that those columns below the Max VG box is used for is to list how humans read it in the final recipe as those values are not used in the calculations to produce the mg's needed. BUT is used to calculate the final strength strength used in the final recipe.

I think(?) I have to disagree (at least as I am reading it , sorry if I am misunderstanding), that those are for display purposes only. The values for:

are all used to define the specifics of the base you are using, and that in turn, alters the specific gravity values of your recipe.

Here are a couple of pictures to illustrate what I am trying to say:
Example #1

Example #1 result:

Now, in the second example I will change only the PG/VG ratio, by reversing them.
Example #2:

Example #2 Result:

Notice, that not only does the nic base description change, but so does the grams amount. All other values remain unchanged.

this can be tested by inputting 'the nicotine strength' to 100 and then looking at the final recipe by scrolling down the page. Notice the differences between when you change that variable. When you input 6mg it calculates the final mix strength as 5.5 mg, but if that variable is not changed and remains at 100 it calculated the final strength in the recipe as 91mg/ml.

Precisely. The final nicotine amount changes dramatically.
However, the specific gravity does not change, because pure nic (1,000mg/mL) has a specific gravity of 1.01 (nearly a perfect neutral 1.00). That is not enough of a difference to alter the calculation. Change the PG/VG ratio though; and the "Grams" amount changes easily.

Does that help at all? Are we at least talking about the same thing? I am really sorry if I am being clueless.
I am trying to help... honest!

 

[DaveP]

I can understand wild variations in small batches such as a 5ml (100 drop) juice mix. It doesn't take much of a slip to throw off a 5ml test mix. An extra drop of flavor or nic could seriously change the mix. I tend to mix 100ml bottles of unflavored and 50ml bottles of flavored juice to even out small slips in adding components..

Using a dropper can mean that you might not get an EXACT amount of anything in a small 5ml (100 drop) test mix, but an extra drop in a 50ml mix isn't a big deal. Scale lag can cause that even if you are careful.