My way of mixing: on a scale

[yo han]

Perhaps this has come up before but I couldn't find anything about it here (not that I did a thorough search).
I read a lot of people are using pipettes and syringes for measuring the different ingredients for their liquids. Some even count droplets (which can only work if all ingredients are added from the exact same type of dropper bottle).
I find this very cumbersome and not accurate enough so I'm using a way easier method (in my opinion): a precision scale.
I keep all my ingredients (nicotine base liquid, VG, PG, distilled water, PGA and flavors) in dropper bottles.
I put my empty bottle on the precision scale (resolution of 0.01 g), zero the scale and start putting in the nicotine base liquid. I then zero the scale again (with the bottle still on it) and go to the next ingredient and so on. This is really easy and you don't waste liquid which gets left behind in your measuring tools.
To use this method you have to know the density of each of your ingredients so here's a list of them:

Nicotine: 1.01g/ml
PG: 1.04g/ml
VG: 1.26g/ml
PGA: 0.8 - 0.9g/ml
Water: 1g/ml
Flavor: depends on the base of the flavor. PG based flavors are roughly the same density as PG, alcohol based flavors are roughly the same density as PGA.

Note: Some VG base liquids come pre-diluted with water (15 to 20%) to make them thinner.
If your VG base liquid is as thin as PG then it's been dilluted, resulting in a lower density.
If this is the case it's best to measure a larger amount (say 100ml) and weigh it. Divide the measured result by 100 and you know its density.

Here's an example of how a recipe translates to my method:



My VG nicotine mix has a density of 1.25g/ml so 4ml weighs 5g
VG without nicotine has a density 1.26g/ml so 4ml weighs 5.04g
Water has a density of 1g/ml so 1.5ml weighs 1.5g
My flavoring is alcohol based and has a density of around 0.9g/ml so 0.5ml weighs 0.45g

This part may seem a bit complicated to some of you but it's really easy.
I think that once you've tried this method you won't go back to using syringes and stuff.

Precision scales can be bought pretty cheap. They're not calibrated lab quality of course but they're accurate enough for this purpose. This is the one I'm using: click
I've compared it to an expensive lab model and it's pretty good!!!
Oh, and you can switch between imperial and metric system. You want to use metric (obviously).

 

[dannyv45]

Measuring by weight is the most accurate way to mix. It's how all the large volume commercial manufacturers mix there products regardless of what the product is (Juices, cosmetics, commercial consumer products etc...). There is a really good thread on this I saw a month or so ago right here in the DYI forum. But for the avarage joe such as myself this gets to be a bit complicated.

 

[Calivapr123]

How do you derive the density figures?

 

[yo han]

The density figures can be found on the MSDS sheets of each liquid.
But you can also derive them from measuring a certain amount of liquid (say 100ml) and weigh it.
EG: if 100ml of liquid X weighs 122 grams, the density of that liquid is 1.22 (g/ml)

 

[THETOTALLYCOOL]

I wasn't sure if I was going to start mixing or not, but this method impresses me greatly. Thanks fro sharing.

 

[jj1257]

Imo, using a scale is the best way to get consistent nicotine levels and repeatable mixes. Been using a variation of this method since May of '11. It's kind of a pita getting started, but definitely worth the effort.

 

[awsum140]

I used to mix paint for automotive repairs using a precision scale. Usually, the color matches were pretty much "right on" because of the accuracy of the measurements. I've been doing DIY for a while using liquid volume measurements and have always felt that mixing by weight is the most accurate way to go. I think the biggest variable is the density of the flavors and it's kind of hard to get a big enough sample, say 50ml or more, to make the errors small enough so they become statistically insignificant. I may have to break out my gram scale and do some sample weights, just for the fun of it.

 

[yo han]

The densities for the ingredients I've listed in my first post are always the same so you shouldn't have to go through the trouble of measuring them again.
I've listed all the main ingredients. The only variable could be in the flavors but these are such a small part of the mix that it's not a problem if they're a bit off.
And the density of base liquids can easily be calculated without measuring as well but this isn't really necessary because of the tiny differences.

Example:

Say you've got a 100mg PG base liquid.

10% of this liquid has a density of 1.01 (nicotine)
90% of this liquid has a density of 1.04 (PG)

So per ml this means:
10% of 1.01 = 0.101
90% of 1.04 = 0.936
Add these up and you're getting a density of 1.037g
Of course you can't weigh this accurate so to round it off you're getting a density of 1.04
As you can see, the 10% nicotine has so little influence on the overall density of the base liquid that it can even be ignored.
For VG it's only a bit more but also negligible. My 40mg VG base liquid should have a density of 1.25 compared to 1.26 for 100% VG. The difference is too small to notice.

 

[awsum140]

Thanks! Next time I mix I plan on using the olde gram scale which with the syringes, gloves, goggles, apron and so on will make me feel more like a druggie or a mad scientist

 

[Bud Man]

Very interesting I am going to have to give this a try.

 

[zoiDman]

Nothing wrong with Measuring by Weight. Nothing at All. Three things I would suggest though.

I would Physically Double Check the weights of the Volumes going to be measure. It would be Very Easy to Measure a Volume using something like a Pipette or Syringe and then Weigh the Amount that was Measured.

And I would Also invest in a Set of gram Standards to Ensure that your Scale is Accurate and Precise over the ENTIRE range of Weights to be Measured.

And Lastly, Never Measure Directly off the Surface of the Scale. Always place a Dish or Tray on the Scale and then Zero Out the Scale.

 

[yo han]

Thanks for contributing to the topic.
I was thinking: it shouldn't be too hard for a programmer to make an e-liquid calculator which displays the weight of each ingredient.
You could predefine the densities of the ingredients you're using and after that it's as easy as using the current range of e-liquid calculators.

 

[zoiDman]

Thanks for contributing to the topic.
I was thinking: it shouldn't be too hard for a programmer to make an e-liquid calculator which displays the weight of each ingredient.
You could predefine the densities of the ingredients you're using and after that it's as easy as using the current range of e-liquid calculators.

Wouldn't be hard at All.

And the UI could have a Settings Page where the user could enter Weights/ml if they wanted to.

 

[yo han]

I'll see if I can find one of the calculator guys being interested in this. It would make things really easy.

 

[kilroyst]

I'm on board with this! I picked up a gram scale and some large squeezy dropper bottles for pg & vg and mixed a couple of batches today. Very easy, consistant and much cleaner than the syringe method i was using.

As for flavors, TPA website has the MSDS listing the density for all their flavors. I did run into a couple not listed, but probably in the ballpark with other flavors of the same base. I use Capella's also but couldn't find any MSDS listing for them but from looking at the bottles the carrier is either pg or pg/alcohol mix; I just assumed them equivalent with a TPA flavoring of the same base.

Thanks for the post!

 

[supertrunker]

What a great idea! and i had no idea the scales were so cheap - i have all the glassware so i can just make it all in one and cut down on the washing up my long-suffering wife has to do!

Superb post - thanks.

T

 

[zoiDman]

What a great idea! and i had no idea the scales were so cheap - i have all the glassware so i can just make it all in one and cut down on the washing up my long-suffering wife has to do!

Superb post - thanks.

T

Wow...

If I had a Wife who would wash all my Glassware, I would probably Measure everything with a 5ml Graduated Cylinder and Syringes/Pipettes.

LOL

 

[jclifford]

It certainly seems like an accurate way to measure your liquids, but really, are you going to trust a $10 gram scale? That, is a horrible idea.

I use $!000+ gold scales and diamond scales on a daily basis, the biggest difference between cheap and quality scales are consistency and the cheap scales are not consistent.

 

[zoiDman]

It certainly seems like an accurate way to measure your liquids, but really, are you going to trust a $10 gram scale? That, is a horrible idea.

I use $!000+ gold scales and diamond scales on a daily basis, the biggest difference between cheap and quality scales are consistency and the cheap scales are not consistent.

What level of Consistence and Accuracy do you need to Mix 30ml of e-Liquid?

I can toss a Standard, any Standard, on my 15 Dollar Scale, at it measures it to within +/- .02 grams of the True Value.

I wonder what .02 grams is in Flavoring ml's ? 1/2 a Drop?

 

[Scubabatdan]

I was contacted by Yo Han to check this thread out, I guess v14 is way over due and I can add fields for grams, would not be to difficult. I will just add a density weight for each item that will calculate the grams needed for the mix based on the desired ml.
Makes sense?
Dan