DIY 3D-printed wet labeling machine: Your fully automated solution for labels

The idea of developing a labeling machine for wet labels came to me during my forays through the Internet. It turned out that there is no good DIY solution for wet labels that would be useful for home use. While there are some ideas that I have found, most of these projects have been forgotten over time.

Many people who brew beer at home, make fruit juices, distill spirits or are beekeepers buy expensive rolls of pre-printed labels. Although these self-adhesive labels are very easy to work with, they do have some disadvantages. For smaller quantities of bottles, it is usually not cost-effective to buy complete rolls of labels in large quantities.

For this reason, I would like to offer a low-cost alternative with my DIY version of a wet labeling machine that anyone can build with a 3D printer.

Wet labels have several advantages:

You can use normal 80g/m² printer paper.
You can simply print the labels with your home printer.
You can produce small quantities and don’t have to buy hundreds of labels.
Ideal for home use as you can change your label layout at any time.

People have become inventive when it comes to sticking wet labels on bottles. However, for many bottles, sticking them on by hand is not an option for me. With my DIY 3D-printed labeling solution, I have designed a machine that does the labeling fully automatically.

Here you can download the files for the friction feeder: Etsy, Cults3D
Here you can find the files for the labeling machine: Etsy, Cults3D

The construction:

The labeling machine actually consists of two different machines. The first machine has the task of reliably separating the labels. The separation is done with a so-called friction feeder. A friction feeder separates paper and labels by means of friction. Once you know how it works, it is relatively simple in principle. The bottom sheet is pulled out of a stack of labels with belts. There is a fixed rubber roller at the top that holds back the second sheet by friction. This means that only the bottom sheet is ever pulled out of the stack. This works really well.

There are two versions of the friction feeder: one for A5 labels and one for A4 sheets. For the bottle labeling machine, I use the friction feeder for A5 labels. This friction feeder can be used to separate paper or labels up to a width of 150 mm. It is important to note that the labeler also works without a friction feeder. In this case, the sheets must be inserted by hand.

The second machine is the real innovation. It feeds the paper with two rubber rollers. The underside of the label is guided over the glue roller. The purpose of the glue roller is to apply glue to the underside of the label. I will come to the glue later.

The adhesive roller transports the label further. The label is then deflected upwards and pressed firmly between the bottle and the pressure roller. To see this process, please watch my video. I have made some slow-motion recordings in which you can see exactly how it works.

The gluing unit:

The gluing unit consists of a container, a glue roller and a wiper roller. I invested a lot of time and many tests in the development of the gluing unit, as it is the central element of the labeling machine.

The main problem was as follows: If too much glue is applied, it pushes out at the end of the label and smears the bottle. If too little adhesive is applied, the label does not hold well and falls off. The amount of adhesive can be varied using two settings.

The thickness of the layer of adhesive to be applied can be adjusted by setting the squeegee roller. To achieve a thinner layer, the two rollers are set very close to each other. Another way to influence the amount of adhesive is the way in which it is applied: over the entire surface, in strips or in dots. I have developed a plug-in system for this in order to be able to attach different rings. The optimum setting depends heavily on the consistency of the adhesive. For me, 2 mm wide strips have proven to be the most suitable.

The large glue roll should be treated with sandpaper to increase the adhesive strength of the glue. If the glue is very liquid, it rolls off the 3D-printed rings easily.

The glue:

The adhesive is of course a decisive factor in ensuring that the machine runs cleanly. I have tested different adhesives and consistencies here.

Wallpaper paste:

I have had the best results with a slightly thicker mixture. You mix the paste into the water while stirring vigorously. You can use a slightly thicker mixture. You can always dilute it afterwards. I have experimented the most with wallpaper paste. It’s particularly good for testing purposes as you can easily remove the label from the bottle after drying. I would recommend the 2mm thick glue rolls for wallpaper paste. The advantage of paste is that it is readily available and cheap. One disadvantage of the paste is the exact dosing quantity. If you put too much paste on the label, it squeezes out at the end of the label. This causes the bottle to make slight
streaks. However, you can hardly see the streaks after drying.

Flour glue:

A very popular means of sticking labels on bottles is flour glue, which is very easy to mix at home. Flour glue is an excellent glue that is food-safe and holds the label very well on the bottle. After a few minutes in water, the labels can also be easily removed.

I have tested less with flour glue as it needs to be mixed again after a few days, which was not possible for me during the development phase of the machine. The glue also starts to smell after a few days.

A big advantage of the glue is its adhesion and ease of production. Basically, it is a perfect adhesive that I still need to experiment with a little. If you have a batch of bottles labeled in a day or two, I would prefer flour glue over wallpaper paste.

Here is a recipe for a rather thicker mixture. You should thin it gradually and keep sticking a label on and checking:

Stir the flour into the water with a whisk.
Heat the mixture, stirring constantly.
Remove the pan from the heat just before it reaches boiling point.
Continue stirring until a smooth consistency is achieved.
Pour the glue into jars.

My recipe: 250 ml water + 75 g flour

Dry gummed paper:

Dry gummed paper is coated on one side with a thin layer of gum, similar to a stamp. As soon as this coating is moistened with water, the adhesive takes effect. This is ideal for automatic labeling, as there is no need to adjust the amount of adhesive and only pure water is required. The label adheres perfectly to the bottle and can be easily removed after a short soaking time. The paper can be printed on with a normal printer, making it ideal for home use. There is no need to mix an adhesive at all.

The clear advantage of this paper is its ease of use. For me, it would be the perfect label material. However, it should definitely be stored in a dry place, otherwise the adhesive will cause the individual pieces of paper to stick together easily, which can cause problems when separating them using the friction feeder. It has been shown that moistening almost the entire surface of the label works best.

Notes:

Basically, I can say that all three types of bonding work very well with their advantages and disadvantages. When the labels are moistened, different moist regions are created on the label. This means that the paper swells in different ways in different places. Some regions remain dry, while others become moist. The paper consists of fibers that swell in different directions. This process can sometimes cause bubbles to form under the label. After drying, the label is usually clean and tightly adhered.

The label cut:

Another important parameter is the orientation of the fibers on the paper when cutting the labels. The labels can be cut horizontally or vertically from the paper, depending on whether the fiber direction is transverse or longitudinal. After moistening, the paper begins to bend in one direction. It is wrong if the label deforms in such a way that it bends away from the bottle. It is therefore important to test how the label should best be cut out.

I cut out my labels with my laser, which works excellently and quickly. I always cut out three pieces of paper at the same time, which makes it possible to produce many labels quickly. It is also possible to create labels with special shapes, for which a laser is ideal in my opinion. I cut the labels with an Ortur Laser Master 3.

Interestingly, the labels with the dry gumming behaved in exactly the opposite way. It is therefore important to carry out your own tests with the paper used.

The electronics:

The machine is controlled via an Arduino, which is simple and inexpensive. Both machines are equipped with a 24V geared motor. The friction feeder is equipped with an infrared sensor that detects the position of the label and switches off the motor of the friction feeder. The threshold value of this sensor must be set in the Arduino code. The wiring should not be a problem.

There is a capacitive start button: when this is pressed, the labeler starts working for a preset time. As soon as the label has been fed in, the friction feeder automatically feeds in new paper, which is positioned while the bottle is being labeled. That’s basically it. I have documented everything neatly with drawings.

Conclusion:

Hundreds of hours of research, design, printing, building and testing went into this project. The two machines consist of over 150 parts that were combined to create a functioning machine, which is always exciting. With projects like this, the outcome is always uncertain. You invest all your energy in a project and at the beginning you don’t know for sure whether it will work. This uncertainty is what makes such projects so appealing and exciting.

There are ups and downs. Every now and then you have to put the machine aside for a few days if you can’t make any progress. But you usually find a solution to a problem at some point. You test and try until it works. I don’t even want to know how many times I’ve taken the machine apart and put it back together again 😉

After all this work, I am delighted to be able to present a well-functioning wet labeling machine. If manual labeling annoys you and you are a tinkerer, this machine is ideal for you. If you have any further questions, please do not hesitate to contact me.

You can download the files here.
You will receive
– all required 3D files in .stl format
– an overview drawing in .dxf and .pdf format
– a parts page with links to the purchased parts
– the circuit diagram
– the Arduino code

DIY 3D-printed wet labeling machine: Your fully automated solution for labels

The construction:

The gluing unit: