One thing I love when Megan Fitzpatrick teaches in our storefront is that I am exiled from the bench room, and I need to amuse myself without woodworking tools or loud music.
So today I decided to experiment more with making gelatin-based glues. In December, I successfully made glue using gummy worms and bears. Then I made some nice liquid hide glue using unflavored gelatin.
I want to develop some recipes that readers can follow and replicate. So today was all about careful measurements, calculations and carrying the gazinta.
Gummy Glue 2
When I made my first few batches, I threw some gummies in the glue pot and added water until the stuff looked like glue. That’s still a valid approach. But I wanted to see if I could create a recipe that was a little better thought out.
Gummy bears are basically gelatin and sugar, with some added colors, flavors and a little carnauba wax to keep them from sticking to each other in the package. Today I’m using a local brand of gummy, Albanese, which is made in Indiana. They are softer than your typical Haribo bear and smell a good deal more.
According to the packaging, the bears are about 44 percent sugar. That makes them about 56 percent other stuff – mostly gelatin. So a rough guess is that 100 grams of bears contain about 50 to 55 grams of gelatin. For simplicity, I’m saying that the bears are 50 percent gelatin.
So a typical hide glue recipe combines 75 grams of hide glue pearls and 3/4 cups (177ml) of water. So, I’m melting 150 grams of bears in 3/4 cups of water. (Useful fact, the Albanese bears are 5g each, so you can count out 30 bears instead of purchasing a drug-dealer scale that weighs in grams.)
I know some of you are concerned about the sugar (won’t bugs eat it?). I have been reading some academic papers that suggest that the sugar might actually make the glue stronger. But we will see.
The gummy glue is cooking now, and I hope to convince Megan’s students to use it on their sawbenches (or at least have a taste of it).
Death Grip Glue 2
When I made my first batch of gelatin glue, I measured out the gelatin using volume because the original recipe used volume. When I poured the water into the gelatin, the gelatin immediately soaked up all the water and left about 25 percent of the gelatin powder bone-dry. So I added more water (I don’t know how much).
When I cooked the glue, it came out watery. Too watery. It would run off joints like water. So I cooked it down until it was snot-like. Then it worked great.
My goal with this second batch of glue is to create a more reliable recipe. First I converted the hide glue recipe from volume to weight. Why? The gelatin is like fine sand. The hide glue pearls are like fine gravel. So there’s some air between the pearls.
When I weighed one cup of glue pearls, they equaled 150 grams. So I put 150 grams of gelatin in a clean glass jar and added 1-1/2 cups (355ml) of water.
Again, the gelatin soaked up all the water, leaving some dry stuff at the bottom. I decided to just leave it for now and see what it looks like tomorrow when I need to cook it.
More updates soon.
— Christopher Schwarz