I've been mixing liquid for about two months now and I'm rather new to this subreddit. I haven't noticed many people mention using any measuring process other than volumes in syringes or graduated cylinders. I've switched over to using a scale and it's definitely improved my workflow when mixing.
After a few weeks of mixing I was becoming a little frustrated with syringes. I mean, it's not like an infomercial montage or something, just a little frustrating. If I reused them I felt like I needed to take the time to clean them well enough that I wouldn't contaminate ingredients with other ingredients or with pathogens. If I didn't reuse them I felt like I was being overly wasteful. I felt that accurate measurement was difficult at times if I didn't have the right size syringe on hand, when using a dark flavoring that makes graduations disappear, or when stubborn air bubbles got themselves in VG.
So instead of ordering a handful of syringes on Amazon I picked up this 200g x .01g scale. In my experience it's been quite consistent. Sure, it's not lab grade, but I've never seen an inconsistency greater than .02 grams (about a drop of flavoring). It's the only precision digital scale I've used, so take my recommendation with a grain of salt. It does have an auto-off feature that can be annoying if I step away from the mixing table. The display is very easy to read with these old eyes of mine.
Now instead of managing syringes I simply drip/stream ingredients straight from their source bottles into the bottle I'm mixing in. The calculator I use gives me weight in grams. I put in that weight, press the tare button to reset the scale to 0, then move on to the next ingredient. Quicker and less messy. You do have to be more careful, I suppose: if you go too quickly and put too much of an ingredient in the bottle you may not be able to correct that mistake!
Speaking of the calculator, here is a link to the thread on ECF about the one I use. You can download it or view the readme at this link. You'll need .NET v4 to be able to install it. It was fairly easy to set up, though you do have to be sure to enter the density of your ingredients (grams per ml): VG is 1.26 g/ml, PG is 1.04 g/ml, water is 1 g/ml, ethyl alcohol is about 0.8 g/ml, and I use a value of 1 g/ml for flavoring. This calculator does have the ability to import data from other calculators but I haven't used it myself.
While I was writing this I came across a blog entry over on ECF by a member named yo han. It contains much of the same info here, but seems worth a read, too. This post is certainly not an exhaustive guide but just a glimpse from my perspective.
Different flavors will likely have different densities, although, it's probably mostly negligible.
Indeed. I did a very quick and dirty sampling of flavoring densities and among 30 varieties from three manufacturers the spread was 3%. That said, all my flavorings are PG-based. Mostly variances in alcohol content I reckon.
Even if there were an appreciable difference between the actual density and the placeholder density it would only be a problem in replication by someone going on the percentage and not the weight. If I know 1.04 grams of RY4 Double in 10ml of eliquid tastes good, it doesn't really matter to me whether that equates to 10% or 9.8% by volume.
I doubt that it's negligible, but if you are building your recipes from scratch under the assumption that they are all the same density, then taste testing and adjusting will rule out any need to understand the densities.
The density differences would really only be an issue if you're mixing a large batch scaled up from a recipe created from small batches with assumed densities.
This calculator is, well, absolutely fantastic.
Drop-down box with your saved recipes, rating system, ingredient management, costings are provided after you enter flavourant costs, can alter total flavor percentages...
this calc does everything! chucking it in the sidebar!
Edit
http://i.imgur.com/VfucOBb.jpg
I've given costs to PG, VG, and my single flavouring so far, and it looks like the price calculator is spot-on accurate!
While weights are more precise, I still prefer syringes. As long as I use the same brands/gauge, my recipes will always be the same. I always share recipes in percentages, so others can replicate it regardless of preferred measurement.
From my former life, I know digital scales vary wildly in consistency. They also require periodic calibration and are not liquid friendly. For me, syringes are the way to go, as the precision differences are negligible at the quantities I work with. If I was making large batches for sale, I'd probably switch to weights as I hate working with graduated cylinders.
Regardless, thanks for sharing your experience. There's no "correct" way to mix juice, insofar as you enjoy your product, save money, and have fun.
>From my former life, I know digital scales vary wildly in consistency.
Y'know, I wasn't very confident in this scale at the time I purchased it, based on my own past life experience. But I was very pleasantly surprised. I borrowed a nice set of gram standards (25, 50, 100, 200g) and right out of the box this scale was just +.03 - .05 across the range. A month after the initial recalibration and it's still dead on. If this scale is an average model then they've certainly come a long way since I was weighing eighths and ounces in my younger years.
Granted, this device leads a pampered life, shut up in a cupboard when not in use and always handled gently. I reckon your average handheld digital scale is being knocked around in the pocket of a pot dealer or coin collector and, well, ya can't expect a sensitive instrument to respond well to that.
I have to chime in because it's killing me to not say something. I deal with scales for a living. For what you're doing, you should be just fine, quite alright even. The best thing you can do for your scale is maintain it, which sounds like you're already doing. Don't expect that scale to last forever or anything, and don't put too much stock in whatever weights you borrowed. The weights you can get on amazon aren't very accurate, and if someone let you borrow actual standards out of a lab, well....they don't know how to treat a good set of weights.
Unless you are making huge amounts, exact weights for your ingredients isn't super important (exact meaning like 8 decimal places). And the 1g per mL standard for water isn't any water that you're using, I can promise you. That's for like ASTM grade 0 water or something (I don't remember), which is insanely expensive and hard to get. Distilled is the best you and I can get without going to a lab supply, and it's nowhere near 1 g/mL. But you'd also never see the difference on that scale.
That being said, weight is always a better way to measure than volume. It's much easier to eliminate possible sources of uncertainty when measurements are made gravimetrically rather than volumetrically. All volume is based on weight anyway, and all weight comes from one chunk of platinum/iridium alloy in France. Google it.
tldr. Keep on weighin' buddy!
Don't worry.. the weights were retired decades ago. They were OIML E2 and are now a family heirloom ;)
If the definition of insanity is doing the same thing over and over again and expecting different results, then yes, I agree that metrologists are all crazy. I'm at least 95.5218% confident in that. Probably.
Well said. I measure by weight as well. I've been doing it since I started mixing juices, it was natural for me as I discovered when I started baking bread that it was the easiest and most reliable method of measuring ingredients.
I've thought about posting about it in the past, but I had trouble getting it all down coherently enough. I never would have explained it all as well as you did.
Glass, graduated suction pipettes. They come in volumes from 1 mL to 100 mL and can be sterilized in an autoclave and re-used. For dry ingredients, or sometimes highly viscous resins, I use a walled, digital scale. Impurities like alcohol can be boiled off at low temperature under vacuum.
I also mix using weight and find it to be much easier and accurate than by volume. To that end, I made this wildly over complicated calculator.