Heated insoles: instructions on how to make homemade devices for warming your feet.

The cold season is fraught with frequent colds due to frequent hypothermia of the legs. Today, this problem can be solved by a technical solution such as heated insoles. It is enough to place them in your shoes instead of regular insoles and enjoy the warmth all the time you are in the cold. This know-how has been used in skiing for quite a long time - you put it in ski boots and enjoy a comfortable ride. But ordinary people relatively recently adopted a convenient device that allows them to forget about freezing feet, colds and various chronic diseases.

Smart insoles Winter+

A relatively new development with surface heating up to +45ºС. It is noteworthy that for their mass production, funds were raised through the crowdfunding platform Kickstarter. More precisely, these heated insoles for shoes were already being produced, but in order to expand the sales market, it was decided to attract additional investments through Kickstarter.

The great popularity of the model is due to a number of advantages:

• Heating is carried out exclusively during movement - by entering a vehicle or into a room, you can save energy and additional hours of work;
• The heating mode is controlled via the Android application supplied in the kit;
• Operation is powered by a battery that needs to be charged after five hours of wireless device operation;
• Resistant to moisture, which ensures reliable operation in all weather conditions.

The +Winter set, consisting of two insoles and one charger, costs $97, but due to the fact that this configuration requires charging each insole one at a time, a set of two insoles and two chargers is available for sale for $117.

In fact, their price is currently very high. In addition, other manufacturers are not standing still and have been producing insoles with similar technologies for several years now, which are much cheaper. Below we will look at a couple of examples.

Chemical insoles

Insoles called “Heat Generator” are a device that allows you to heat your feet in conditions where there is no possibility of using a battery or accumulator - during long hiking trips, outdoor recreation, fishing, etc.

Characterized by the following features:

• Provide heating for 6 hours to a temperature of 36 to 40ºС;
• To use, just open the package and take them out into the open air, where heat will begin to be released due to the chemical process;
• Made from safe, non-toxic materials that meet safety regulations;
• Two size options - 22cm for shoes from sizes 33 to 38 and 25cm for shoes from sizes 39 to 45.

The cost of a chemical shoe warmer varies depending on the number of pairs purchased - from 5 to 9 - $3.17; from 10 to 19 – $2.25; from 20 to 95 – $1.58 per pair. Intended for single use only.

Battery powered insoles

The Therm-ic Perform is an electric, battery-powered boot warmer that has already become an integral part of the equipment of well-known ski and snowboard boot manufacturers such as Atomic, Salomon and Burton. In order to heat your shoes with Therm-ic Perform insoles, just install them instead of the usual ones and connect them through a special cord to the battery.

The system allows for continuous temperature support in domestic climatic conditions from – 25 ºС throughout the entire day of skiing. The feeding element can be secured both on the outer part of the boot and on the belt; the only limitation in the location is the length of the supply cord.

Therm-ic Perform insoles cost $22.50 per pair.

SIDAS - battery-powered insoles from a well-known French manufacturer, which has prioritized the comfort of wearing shoes in any sport. This model with an electric heater was developed at the Podiatech medical research center using orthopedic structures and elements that ensure correct foot placement and effective functioning of the athlete’s musculoskeletal system during training or competitions. And since the thickness of SIDAS does not exceed the thickness of a regular boot accessory, they can be easily used for warmth in everyday shoes, especially since the cost of the insoles is only $36.67 per pair.

Thanks to heated insoles, a person will not have any problems during the cold season. At the same time, he does not have to worry about any cataclysms or negative consequences - the power of the electric heater is absolutely safe for human life, and chemical models do not have any harmful effects. Therefore, you can safely put them in your shoes and forget about freezing feet at any temperature and in any situation.

Winter can be very cold and harsh. This is especially true for places close to the Arctic Circle. Regardless, everyone experiences a cold month or few days from time to time. At this time, your feet can become very cold, and then you are not far from getting sick. Heated insoles can help you cope with frost.

Who will benefit from insoles?

In addition to cold days and very harsh living conditions, there is also simple everyday life. Such a device will not be superfluous for people whose feet are simply cold. They are mandatory for people who spend a long time on the street, whether for work or vocation. I am now talking about sellers at open markets, for whom the working day involves being in different conditions, especially in winter.

In addition, battery-powered heated insoles can help fishermen, for whom this is, if not a mandatory attribute, then desirable and recommended. Hunters also fall into this category, along with people who also work outdoors, regardless of the time of year. These could be farmers, builders, drivers.

How the insoles work

The overall design always consists of several unchanged parts. We are talking about the insole itself, the heating element, which is usually a thin thread of conductor, and the power source.

You've probably already guessed that you can make heated insoles yourself. To do this, you need to select the components yourself. There may be some improvements that depend more on the craftsman who makes the insoles.

When choosing a conductor, be sure to take into account the resistance; you can’t go wrong with it. Calculations play a very important role when working on insoles.

A simple system, a photo of which can be easily found on the Internet, provides for the presence of several power sources. Usually they use simple batteries, which are installed from three pieces. Why? It's all about the several modes of operation of such insoles.

In the first, the batteries will operate at 2/3 of their capacity. This mode ensures that the insoles are constantly kept warm. The second uses the full power of the power source, while the insoles heat up much more and become hot.

It is stipulated that in this mode they should not cause burns or severe discomfort. This is needed more for very low temperatures. Both of these modes should be tested several times before using the insoles personally.

There is no need to save time on this process, as faulty insoles can cause serious harm to your feet.

Materials for making insoles

Nichrome is a good conductor of heat. A thin thread of 2 tenths of a millimeter will be enough, which will reach 25-30 centimeters. After connecting it to the power system, you should check the conductor. This is necessary in order to find out how homemade heated insoles will behave.

To do this, take a not very thick cloth, place the thread connected to the batteries in this cloth, and hold it tightly in your hand. The temperature should be high enough to heat your hand, but not too high so as to burn it. Based on the results obtained, we adjust the temperature.

Let's return to the power source. As mentioned earlier, simple AA batteries will do. Two of these batteries can provide you with a charge of just over 250 milliamp hours. At the same time, three batteries contain up to 400 milliamp hours. Next, we select the required battery volume, which will determine the operating time of the insoles in heating mode.

The instructions on how to make heated insoles at home will tell you more situational components. These include additional conductors that will connect the nichrome thread and other consumables.

Manufacturing process

First you need to connect a nichrome thread with a wire that will lead to the batteries. To do this you will need contact sleeves. The cable should be at least 45 centimeters longer than needed to reach the insole.

How and where the thread will be laid is something everyone will decide for themselves. Most often it is concentrated in the front part of the insole, which freezes the most.

Next you will need to work with a simple needle and thread. Yes, the heating element needs to be fixed, and almost nothing is better for this than a simple thread. At the same time, the other end of the wire will receive a 3.5 mm plug that will connect to the battery system.

Next comes the power source. it will be attached to the leg, and therefore it needs a body. it is selected based on batteries with one condition - no matter how many of them you take, the case must accommodate one more. This is needed for the controller and the connector that will work with the mini jack.

Having finished working with the soldering iron, you will need to secure the whole thing, for which you will need hot glue. To prevent the batteries from falling out, take two simple rubber bands and put them on the top and bottom of the device.

Everything that we have now needs to be somehow secured to the leg. A simple Velcro tape works well for this. It will require holes in the body that will need to be drilled. Then we connect the two parts with threads and the device is ready for use.

Photo of heated insoles

These are winter insoles with autonomous heating from the battery with adjustable temperature.

What materials are used for this product?

During production, several important principles were taken into account. Firstly, the base of the insole should be made of a material that does not conduct heat well. This is necessary to ensure that there is no heat leakage down to the sole. Accordingly, there should be good heat transfer upward towards the foot. Therefore, to create this useful product with my own hands, I used ordinary felt insoles 5 millimeters thick.

To save on energy costs, it was decided to place the heating element only in the front part of the insole, that is, only where the feet will touch. For this purpose, a nichrome thread 48 centimeters long was used, the wire cross-section was 0.3 millimeters. This is a nichrome thread from a 300 Watt heating device. This is the thinnest wire that the author has found. Purchased at a regular hardware store for 20 rubles.

The temperature is set by a voltage regulator purchased from this Chinese store. Go and write in the search: Voltage regulator from 4 volts. In the same store you can buy ready-made heated insoles.

How the master combined all the parts into finished insoles

The nichrome wire was laid across the insole so that when bending there would be no creases or displacement of the wires. The wire is evenly sewn to the base. In some places double-sided tape is glued so that a second layer can be installed. It is made of genuine leather, which is a fairly dense material that transfers heat very well from the thread to the feet with minimal heat loss and can withstand the heating of the threads themselves. The seams will run between the wires.
After the firmware is completed, the excess parts will be cut off and the insole can be prepared for further installation. Two ends of 2 centimeters each are brought out from the insole. The thread is laid in a zigzag, the distance between the strips is 2 centimeters, in the nose part it is 1.5 centimeters each.
We take two pieces of stranded wire 1.5 meters long. In this case, a wire for car audio was used. It is of very high quality, flexible and less dull in the cold. The wire cross-section is 0.05 millimeters. We connect this wire to the insole. In order to make the connection as thin as possible, it is twisted and clamped with a metal sleeve.

The whole thing is covered with heat-shrink insulation on top. We lay the wire, sew it along the bottom side with regular threads to the middle of the sole.
So, the insoles are ready, stitched, wires are connected. It turns out neat. If possible, you can put another insole, sew it or glue it. This will significantly reduce heat loss.
Next, measure the required length of wire and cut off the excess. Now we connect the insoles in series to the required connections. You can use regular connections purchased from a car dealer.

We measure 15 centimeters and make two cuts. There is one such connection on each insole. We install the remaining part of the entire structure.
Detachable connections create convenience in that you can quickly disconnect the contacts and change shoes and dry the insoles.

Power supply for electric insoles

The entire shoe heating circuit is powered by a nickel-metal hydride battery with a voltage of 7.2 volts, 5000 milliamps per hour. Operating time from 5 to 11 hours of continuous operation. The power source may be different. The degree of heating of the insoles depends on the voltage and current. Heating is noticeable from 4 volts. High-quality work from 5-12 volts. The maximum operating temperature is 60 degrees, this is an excessive temperature, but the material can withstand it. The battery and regulator are attached to a leather strap and attached to the waistband.

Heating depending on the regulated voltage (approximately):

4V-0.6A=23-27 C
5V-0.7A=27-32 C
6V-0.8A=32-35 C
7V-0.9A=35-37 C
8V-1A=40-42 C
12V-1.3A=65 C

Feet are very sensitive to low temperatures. Even the warmest and highest quality shoes are sometimes unable to completely protect your feet from the cold. The result of hypothermia in the feet is illness, and most importantly, a decrease in immunity. Therefore, it is very important to keep your feet warm. In winter, heated insoles will do the job perfectly. They can be purchased in stores or made yourself.

Heated insoles

The design of heating insoles is quite simple. There are two types: chemical and with heating element. Each operating principle has positive and negative sides.

Chemical ones are often disposable. Sold in sealed bags. After printing, shake them to initiate a chemical reaction. Then they are put into shoes or glued to socks (if the manufacturer has provided a self-adhesive side). Heating occurs due to the oxidation of iron. To prevent burns, sodium chloride and salt are added, which slow down the oxidation process. Sawdust can also be added to the mixture to absorb moisture and odor.

Chemical heaters operate for up to 6 hours. The main condition is air circulation to supply oxygen for the oxidation process. If the shoes fit tightly, your feet will not feel warm.

Insoles with a heating element are distinguished by the fact that the heat comes from a metal wire or plate. They are connected to a battery, but you can use regular batteries if you wish. Heated insoles are:

• wired;
• wireless.

Wired ones are connected to an external battery. Some models have a power regulator. Thickness is standard. The operating time of the wired heater reaches 12 hours.

In wireless ones, the battery is built directly into the heel. Operating time from 3 to 6 hours. There are models with a remote control that allow you to turn it off, for example, when entering a building. Insoles without a remote control will have to be removed.

Manufacturing instructions

The insole with a heating element has a very simple design. Therefore, you can make them yourself. To make heated insoles with your own hands, you will need the following materials:

First you need to connect the nichrome thread to the MGTF wire. You can use hot melt glue for this. Then you should decide where the nichrome wire will be laid. It all depends on which part of the feet freezes the most. Or you can attach nichrome over the entire surface.

Next, you need to lay the wire in a spiral at a distance of 1 cm. To attach nichrome, you just need to sew it with a thick thread. Make stitches at a distance of no more than 3 cm. Solder the selected plug to the second end and insulate it with heat shrink. This will allow you to quickly connect and disconnect from the power source.

For the power source, two AA batteries will be sufficient. The case can be taken from an old radio, flashlight or, for example, Tetris. You need to solder the socket for connecting the nichrome wire and secure it with hot glue. Make two slits in the body. To attach it to the leg, take a strip of fabric with Velcro sewn on and thread it through. Insert batteries.

This electric heating of the feet can be done in 1 hour if all the materials are available. The wire is heated to approximately 35 degrees. If this is not enough, then you can add a third battery to the circuit.

Review of models from the store

Of course, you can make heated insoles very quickly and for little money yourself, but they can fail at the wrong time. And they look much worse than store-bought ones.

Manufacturer: ThermaCELL

ThermaCell heated insoles are designed for winter and any cool weather. Waterproof and remote controlled, which avoids discomfort when operating with gloves. The battery is designed for 5 hours of operation and 500 charge and discharge cycles. Fully charged in 3 hours.

They have 3 operating modes:

1. Off (no heating).
2. Medium heat (about 39 degrees).
3. High heat (about 44 degrees).

Country of origin - USA.

Blazewear Company

Simple and comfortable insoles. Easily cut to the desired shoe size. The carbon plate emits excellent infrared light, thanks to which heating reaches up to 46 degrees. The plate is located in front of the fingers. You can use both regular batteries and AA batteries. The battery charge lasts for 3-5 hours. They have two control units on which the insoles are turned on and off. Insole thickness 5 mm.

This simple invention will always come in handy when ice fishing, hiking or in cold weather.

Attention, TODAY only!