Measuring colorant by weight instead of volume

[Vicki C]

I am getting ready to do some colorant tests using different concentrations. My approach in the past has been to just wing it and add as much as I think looks good. But, I am hoping to change my haphazard ways and am trying to create reproducible results with oxides, ultramarines, and other colorants. I can’t find a resource that uses colorants by weight - all are by volume and generally the starting point is 1 teaspoon ppo for micas and 1/2 teaspoon ppo for oxides. I know that the amount of colorant by volume is likely to vary based on how “fluffy” the colorant is. I could also measure a teaspoon of a colorant and then see how many grams it would be. Does anyone measure colorants by weight or know of a good reference that does so? Thanks in advance.

 

[amd]

I have tried to do color by weight instead of volume and what I found is that weighing my colorant becomes too time consuming for the speed that my soap likes to setup. I think if you're organized enough to weigh your colorant before you start making your soap (I am not) it would work, or have a slow moving recipe. When I tried it, I took the 4 colors that I used the most and weighed out what I considered to be a consistent tsp of each color. They did vary slightly, whether that is because of a slight difference in volume to weight, or because one colorant was actually heavier than another, is something to consider but at the volume I was working with it, it didn't seem worth the time to investigate further. I took it for what it was. (and really the difference was in 0.x grams so negligible for the most part) In the end I decided this did not work for how I make soap, and the batch size that I make. Perhaps if making large slab molds it would be cost efficient for tracking inventory and batch repeatability, but at small scale I don't see a value. That's my two cents though - you may feel differently, so I hope I don't discourage you if that's what you want to do.

 

[Vicki C]

Thanks amd - understood and agree that it might not make a difference. I decided I didn’t like my usual chaotic approach of adding colorant until I liked how the batter looked, rather than planning how I wanted the soap to look. I also wanted to improve my methods for dispersing colorants (other than micas). So, I came up with the following method -
1) I weighed out 10 grams of, for example, iron oxide, and added 30 grams of oils. I added some rocks to help with mixing and shook up the colorants in the bottle.
2) I used silicone brownie molds and measured the weight of soap batter (and % oils) for each sample.
3) I measured the weight of 500 drops so I would know the weight of colorant plus oil I was adding. (Taking into account, in this example, that the iron oxide is 25% of the total weight).
4) I planned out a series of percentage colorant goals - been playing with this on different batches, but starting with 0.01% and working up to 0.5%.
5) I created a spreadsheet that would show how many drops I needed to add to achieve a given percentage of colorant per total oils, taking into account the amount of colorant that is subtracted with each sample.
6) I poured the samples obviously starting with the lowest % first.
7) When they are hard enough I scratch the percentage and the colorant on the back, and keep them for posterity.

I know this all may seem like overkill (and is) but it is my little diversion I have been playing with in these Covid days. My husband says I look like a mad scientist hunched over my soaping setup - which is accurate. Also, I’m sure there are flaws in my system, but this is all better than what I was doing.

I have been posting my results in the “what soapy thing have you done today” thread but here are examples. These are chrome oxide, annatto, ultramarine, and iron oxide.

Thanks for listening!

 

[AliOop]

@Vicki C I am not a person who would ever do this, but I am so impressed that you would, and that you took the time to share your results.

After watching some YT soapers using pre-mixed micas that they keep in little squeeze bottles, I could see myself doing that. My only hesitation is that I don't know that I'd use them up quickly enough before the oil gets rancid. But perhaps adding ROE to the oil before mixing would take care of that issue. Hmmmm. You've got me thinking now!

 

[amd]

@AliOop using vegetable glycerine to premix the colors would take out the oil rancidity problem, if you're not adverse to adding a touch more glycerine to your soaps. I do this for mica swirling on the tops of my soaps. In this case I do measure colorant by weight and mix at 1 part color to 4 parts glycerine. [glycerin? ugh, never sure why I question the spelling of that word every time I see it...] I keep mine in the 2oz travel bottles with a marble for easy mixing as the mica does eventually settle out if not used regularly.

@Vicki C exactly what you did was going to be my next suggestion. YouTuber I Dream of Soap did something very similar with her colors (she has a video from about a year ago sharing her method), that I put on my "when stuff isn't so crazy" to do list, as I always seem to grab the not-quite-right color - and I have a bunch of new colors that I'd like to see what they look like before I commit to a soap batch. You might want to check out the video, she has a neat way of organizing her colorants numerically. hashtag goals. lol.

 

[Vicki C]

Thank you! Yes I know of I Dream of Soap, she is really good on being organized and tidy. Me... err... well... I will look for her colorant video, I copied her TD in oil method. Yes I too was thinking about rancidity, and was thinking ROE. I am waiting on new squirt bottles, the 4 oz ones I bought off Amazon are terrrrrrible and leak like crazy, but when I transfer everything to the new ones I ordered I’ll add a little ROE. Mostly I am entertaining myself, love colors and problem solving so I’m in dork paradise in my soap studio.

 

[AliOop]

Thanks @amd, I happen to have quite a bit of glycerine so I’ll try that!

 

[TheGecko]

When I first started soap, I carefully measured out my colorants, then I started winging it. And winging it is okay if you are making a bunch of one-off soaps all the time, but if you want to make ‘stock’ soaps, then you need to have consistent results that you customers can count on.

I had thought about weighing out my colorants and additives as I do my oils, butters and fragrances and had looked at these light plastic dishes with pour spouts on Amazon and then thought...how in the heck do I weight a ‘smidgen’ or ‘touch’ more? So instead of little plastic dishes and drug scale, I bought an extended set of teaspoons.

 

[Vicki C]

I thought about the tiny measuring spoons too but decided to go with weight. A drug scale would make my life easier, but my approach is to weigh a large number of drops from a pipette and then divide by the number of drops and by the dilution rate to get the total weight of the colorant, which I measure as a percentage of oils. I think I’m just not great at guessing how colors will turn out - my system of setting up standards will help me get the colors in my mind. I hope. We’ll see. The plan is to have my colorant calculator easily accessible so I can quickly figure out how many drops to add given a certain weight of soap batter. Voice activated and on a big screen on one wall. (Kidding, but wouldn‘t that be fun?) I usually am just winging it and combining colorants so I’m not sure what has caused the results I get. The soap in my avatar had beta carotene, turmeric, annatto, and chrome oxide, and I like how it came out, but it was a happy accident.

 

[TheGecko]

....but my approach is to weigh a large number of drops from a pipette and then divide by the number of drops and by the dilution rate to get the total weight of the colorant, which I measure as a percentage of oils. I think I’m just not great at guessing how colors will turn out - my system of setting up standards will help me get the colors in my mind. I hope. We’ll see.

That makes sense if you are using liquid colorants...I use dry so measuring spoons work better for me. Whenever I get a new colorant, I do a test batch with 16oz of oils and divide into four cups. I then use the 'standard' of 1 tea PPO. Right now I have well over 60 different clays, micas, powders, oxides, pigments, and ultramarines...I dislike it. My goal is to cut it in half at least because I can mix colors together...red and yellow = orange,, red and blue = purple, yellow and blue= green. And you can use white and black to brighten or darken a color.

 

[Vicki C]

I have always used powdered colorants in the past - trying these premixed ones because of my personal struggle with getting good smooth mixing with no specks. And yes - mixing colors is all the fun! Once I get through round one I’m going to test some blends with a steady % of one color and varying the others.

 

[TheGecko]

When mixing anything but Mica, I mix with water a good half hour ahead of time to give the colorant plenty of time to soak up the water...so much smoother.

 

[Vicki C]

Do you always use water? I’m wondering about water v. glycerin v. oil.