Make Your Own Clear Glue
For the last few months, I have made multiple batches of glue from gummi bears and grocery-store gelatin and used it to assemble projects that are not chairs.
Why not chairs? Years ago, I had a chair experience glue failure. The rear leg of a three-legged walnut backstool came completely apart. The sitter was thrown to the floor, and he was thankfully unhurt. But that moment scarred me.
That was the last project I ever used Titebond’s hide glue on. Yes, it was a fresh bottle. Yes, unexpired. Kept in a cool, dry place (e.g. not my butt). I had used the product for many years before with no problem. And then – 100 percent glue failure.
I assume it was a bad batch that escaped the factory. Titebond is a solid company. I’ve toured its facility and I know – by name – many of the principals.
But when you see a stick almost make another man pregnant, it changes you.
So there has to be an extremely high level of trust if I’m going to let you ram your tapered tenon into my wet and sticky mortise.
Back to the glue that I’m making: I have been surprised by how adaptable the recipe is. With gummi bears, you throw a bunch in the pot with a little water until they melt. I use a glue pot that holds the temperature at 140°-150° (F). Then add a little more water until it is the consistency of glue. If it gets too watery, add bears (just like my grandad used to say).
The only problem with gummi bear glue is the color. If you mix all the bears, it looks like the green stuff one finds in a baby’s diaper after said baby has gone on a tasting tour of a jar of Vaseline.
So it’s a weird color to use with light woods, such as maple. Looks great with purpleheart, though.
Gummi glue holds surprisingly well. I thought that all the other stuff in the candy (such as sugar) might weaken the joint. But if it does, I can’t tell. I have walloped the hell out of gummi bear joints, and they hold as well as any glue. And yes, they are reversible with heat and alcohol injections.
They smell rather nice. And clean-up is delicious.
Gelatin glue is a bit different. I’ve been making a form of liquid hide glue using Knox gelatin from the supermarket, water and uniodized salt. What I’ve made so far looks and behaves exactly like hide glue, except it is nearly clear and has almost no odor.
My recipe started with one that Don Williams gave us years ago when I was the editor of Woodworking Magazine. You can kinda-read the article here. Sometimes they make you register.
The original recipe used hide glue pearls (about the size and shape of Pop Rocks). And gelatin is a fine powder (like hourglass sand). So I’ve played with the amount of water to get the right consistency. I think I have it nailed. Here’s what works:
Stir together 150 grams of gelatin and 350ml of water and let it sit overnight. The next day, cook the mixture for two hours at 140° (F). Then immediately refrigerate it.
The next day, cook the mixture again. As soon as it turns liquid, add up to 75 grams of salt. I basically add salt while stirring until the mixture will take no more salt and the crystals begin collecting at the bottom of the jar. Cook this mixture for two hours at 140° (F). You are done.
You can now pour the stuff into whatever containers you like. I have some in a ketchup dispenser. And some more in small Tupperware containers. And some smaller quantities in paper cups. And I keep it all in the fridge.
I’m sure there are other inventive ways to portion it out.
When I need a little, I cut some off with a knife – the stuff is like hard Jell-O. If I’m in a hurry, I put it in a paper cup and microwave it for about 10-13 seconds – which is when the glue just starts to melt. Then I stir it up. The heat from the melted glue turns the rest of the stuff in the cup to liquid.
If I’m not in a hurry I put the cup in my glue pot, which is filled with water. It melts in about 30 minutes to an hour.
Does it Work?
The answer is yes. I hesitated to write this entry because I assume it will be flooded with comments about how I can never know the long-term prospects of my glue.
But I know it’s collagen. I know it has been treated well. And I know how collagen glue has survived for thousands of years if taken care of.
I actually have a little more faith in my glue than what I buy at the store. I don’t know everything that was added to the store-bought stuff. Or if it was overheated or mishandled in shipment. Or if it was made on someone’s last day at the factory (“Ha-ha, watch this”). Oh, and what do I use to glue my chairs these days? Old Brown Glue, until I get a little more confidence with the stuff I’ve made.
And so I kindly ask that you hold your criticism until you have tried it yourself and have a bad result to report. That, I would like to hear.
Or if you insist on adding some speculation, please do so only in the form of a limerick that begins, “There once was a sailor from Mazores….”
I’ve actually been curious: How well/ how easily reversible is the gummy bear glue? Was thinking about how well it would or wouldn’t work for veneering, as compared to boiling down a non-gummy based animal.
When I use animal protein adhesives for bookbinding I use a little mug warmer which lets you set the temperature. It was fairly cheap from Amazon, takes up less space on the bench than my water jacket glue pot and I don’t have to worry about it going dry. I keep my glue in little Japanese lunch things that are stainless and about the size of a short mug. They have a plastic lid with a seal and cost a few dollars each at the supermarket. Straight from the fridge to the mug warmer and back again.