DIY print head for a 3D printer. Too much plastic is extruded

If you have never wanted to build a 3D printer from scratch, if you bought Picaso Designer to “just print”; if your printer is under warranty, if you have less than 6 hours to get to the technical service. support, then NEVER disassemble the print head - go to technical support. support. Dedicated to the rest...

Because of this pretzel, my next 3-hour torment.

I will not describe how to disassemble the print head of the Picaso Designer printer. But I’ll try to briefly explain how to assemble it (10 steps). The photos do not show hand positions and finger placement during assembly, maybe someone will make a video on this topic...

Let's get started:
We won’t check the completeness: let’s assume that there are no children or cats nearby - we are in a vacuum, and all the screws and strips are neatly lying in different shallow jars. Nearby there is a suitable hexagon and a short Phillips screwdriver.

Step I: assemble the feed mechanism. We simply return the pose wheel to its place. 1, press it with a pin pos. 2, press the pin with screw pos. 3. Done :)

Step II: put the print head into the printer. We assemble the round rails pos. 4 in a pile, place the print head on them in the desired direction. We check that all small parts (especially 4 small metal strips in the form of letters t, position 5) are in place and at hand. On the picture serious mistake: top cover pos. 6 is not unscrewed or removed: it must be removed. Otherwise then the wire additional cooling pos. 7 (pictured in step III) will knock down the bar pos. 8. This was the last easy step.

Step III: right wall pos. 10. Everything is obvious: insert the ribbons pos. 9 into the hole in the right wall pos. 10, fasten the tapes pos. 9 on the print head using two strips pos. 5.

The operation starts at the following position:
in the left hand
- two tapes pressed tightly against each other with the thumb and forefinger in the ear of the print head (ear - pos. 11);
- round rails pos. 4, held by other fingers and palm;
in the right hand:
- right wall pos. 10 (thumb and little finger);
- plank held by the nail of the index finger, pos. 5.1, pos. 5.1 already in the hole in the right wall pos. 10;
- plank held by the nail of the middle finger, pos. 5.2, pos. 5.2 already in the hole in the right wall pos. 10, on the other side of the tape pos. 9.

The operation consists of replacing the fingers of the left hand on the ear. 11 planks pos. 5. Bringing the right and left hands together. The protrusion of the base of the print head, pos., should automatically fit into its groove on the right cover. 12. The entire structure must remain on the rails pos. 4.

To get to the starting position Another person can help you if
- he's not an idiot
- he doesn’t piss you off when he acts like an idiot;
- instead of fingers and hands he has tweezers, because... when not cover removed there is not enough space in the printer (removing the cover requires 7 star screws bigger size, you can use the screwdrivers included with the printer).
- a person does not stick his head in to see everything, but blindly hits with his tweezers where he needs to.
If there is no such person: patience, sleight of hand and God will help you.

Step IV: insert the bar pos. 8 for fastening the wheel pos. 1 in the right wall pos. 10. You need to put on the bar pos. 8 on the wheel axle pos. 1, slide the bar pos. 8 onto the axle of the adjacent wheel, and at the risk of destroying step III, insert pos. 8 in the groove of the right wall pos. 10.

Of course, you can include this step in step III: just hold the pose bar with your ring finger with your left hand. 8. If you are helped by a person with tweezers or if you have long pianist fingers.

Step V: back wall pos. 13. We come across the protrusion of the rear wall with the fan pos. 13 in the groove of the right wall pos. 10. It's simple. Just don't break step IV and step III.

Now in your right hand stick
- right wall pos. 10, strips pos. 5 are still in place and have not fallen out: they need to be controlled;
- bar pos. 8 does not fall with a slight ringing sound on the base of the print head pos. 12;
- rear wall pos. 13;
- actually herself print head on round rails pos. 4.

Step VI: First time we need a screwdriver (phillips). Maybe a second time: I was in step I too. We find the bar pos. 14, insert it into the right wall pos. 10, secure it a little with screw pos. 15 to round rail pos. 4.1. Now I also have this bar in my right hand :)

In the photo it seems that this is the first step. Nonsense! All the same, bar 14 will fall off every time, despite screw 15.

Step VII: left wall. Similar to step III, but mirrored. Additional complications:
- pull the tape on the left side of the figure over the left ear, pos. 16 (item 16 is indicated in the photo in step V);
- the structure in the right hand tends to fall apart, because there is also a tape in the left ear. 16 must be held;

You need to get into 5 slots on the left wall (at 6, actually, but the slot for the fan switch is large) all the disparate parts in your right hand. Simultaneously. And so that the planks pose. 17 did not fall out, but secured the tape.

Ta-dam!!!
Before starting this step, check the wires: they should all be free. The dangling fan pos. 7. On this step It’s better to throw it back over the back wall with the fan pos. 14 (in the photo it is already thrown forward). And also check the heating wire so that it is in line with the plastic supply motor, pos. 18 distributed.

Step VIII: lay the wires and close the top cover pos. 6 (position 6 is indicated in the photo in step II). If everything is fine and the print head looks perfect without cracks or gaps, look into the plastic supply hole: there should be no wire pos. 7! Wire pigtail pos. 19 should be to the right of the pin pos. 2 (see photo of step VII - it’s not correct: the wire should be to the right of the pin!!!). We tighten all the screws. 15 pieces. Together with fan pos. 7. I don’t know in what order.

Step IX: Before turning on the printer, look at the ribbons. They must be taut. Otherwise, remove the printer cover, another cover, and tighten the loose ribbons. There is no photo without covers: I forgot to take a photo.

Step X: turn on the printer. I hope everything worked out.

Now is the time to remember:
- how could these 3-4 hours be spent more usefully: sleep, work, go to a restaurant/theater;
- what a wonderful manicure I had 3-4 hours ago;
- how much nerves and effort had to be put into creating a vacuum around the printer;
- why was it necessary to call a person who sincerely wanted to help an idiot, and how to put up with him now;
- how could all this be avoided if you simply took the printer in for repair (even if not for 3-6 hours, but for a week);
- how sweetly the managers at Top3DShop smile when they give you a working, clean, lubricated, calibrated printer, and it works, it works like a charm!!!

I hope your printer works too :), good luck!!!

An extruder is a print head or, in other words, in simple language, a device for extruding molten filament. The concept is used primarily in FDM printers that work with thermoplastic materials: ABS, PLA and other types of plastic. This key element A 3D printer, the quality of which determines the accuracy and cleanliness of the print.

The device is conventionally divided into two parts: the hot end is a heating element with a nozzle, and the cold end is the part of the extruder responsible for supplying plastic to the nozzle. The feeder consists of a stepper motor (models with several windings with discrete (step) rotor movements) and a gear system for directly feeding the thread into the hot end. You can ask the price for components in the catalog http://makerplus.ru/category/extruder-3d-printer.

Types of extuders for 3D printers

• Direct extruder. The feed elements are attached directly to the nozzle body. The plastic thread is removed from the spool using a gear and a pressure roller, and passed through a heating coil directly into the nozzle. To prevent premature heating of the thread, there is a heat-insulating insert between the “hot” and “cold” ends. Advantages of direct extruders: more accurate supply of plastic, easier retract (reverse feed of filament at idle). Disadvantages: large mass, which affects the accuracy and speed of printing.
• Bowden extruder. Unlike a direct extruder, the hot end and cold end are separated in space and connected by a Bowden tube (usually made of Teflon), through which the filament is fed into the nozzle. The hot end is mounted on a movable carriage, the cold end is mounted on the printer frame. This extruder for a 3D printer has important advantage– low weight, making it suitable for use in delta printers that are extremely position-sensitive. The disadvantage of this model is the difficulty of feeding plastic in the opposite direction when the mechanism is idle.

There are also options with double and even triple nozzles. Such devices are used for printing multi-colored models or several types of plastic. In general, this technology is quite crude, so experts prefer to use single extruders.

What you need to know when choosing an extruder

The most important parameter is the diameter of the nozzle. The smaller it is, the more accurate the print and the more effort required to push the thread. Standard diameters are 0.2-0.3 mm and 0.4-0.5 mm. The feed force is controlled by the adjusting screw - if it is tightened tightly, the engine energy will be wasted on overcoming frictional forces, if it is tightened weakly, the gear will slip and leave dents on the rod.

Friction also occurs between the feed mechanism and the nozzle. In this place there is a heat-insulating insert - as a rule, it is a metal sleeve with a fluoroplastic core. Cheap models may not have a fluoroplastic core, which negatively affects the operation of the extruder.

Another key moment– selection of a stepper motor. For conventional motors, the microstep parameter is 200, which is clearly not enough for printing small parts. The best option in this case, a motor with a microstep of 400 units.

Which extruder for a 3D printer should you choose?

It all depends on the context. For models with a Cartesian coordinate system, it is better to use a direct extruder, for delta printers - with a Bowden tube. Take a look at the store http://makerplus.ru/ - they have everything you need for printers of any type.

As for choosing a manufacturer, first you can purchase a universal E3D extruder - both English originals and Chinese and Russian analogues of good quality are available on the market. In the future, you can switch to more specialized models (for example, with ceramic nozzles) or make your own assembly from available components.

3d printing

An extruder (from the English word extrude) is the print head of a 3D printer. The name of this part (the translation of the term is to extrude) fully corresponds to the principle of its operation: the extruder squeezes a special material through a hole, thereby creating layers of the object. Glue guns, tubes of paste and others work in the same way.

In most cases, a 3D printer prints objects from thermoplastic ABS and PLA (scientific filament or plastic thread in everyday life), so it is worth analyzing such extruders.

In fact, the extruder (print head of a 3D printer) is the main mechanism and the quality of printing on a 3D printer depends on it. Even if you decide to assemble it completely, then it’s worth splurging on an extruder and buying a ready-made and tested unit.

The print head of a 3D printer consists of two elements: a nozzle and a filament feed mechanism. The nozzle has a heating element and is also called a hot-end. The heater looks like a rectangular aluminum device.

The filament supply element (cold end) is a small block consisting of a clamping mechanism and a gear. Such a mechanism must be connected to a special electric motor (via a gearbox). The principle of operation of a 3D printer is this: the wheel rotates and sucks out the filament, transporting it to the hot-end. There, it melts (thanks to the heating element) and is squeezed out through the nozzle.

Most often, the heater is a nichrome spiral or several resistors. The hot end is made of a thermally conductive metal (such as aluminum). A special temperature sensor is attached to the nozzle to monitor and regulate the printer’s condition.

The hot end and cold end are separated by a heat-insulating wall made of heat-resistant PEEK plastic. Fans are built into the cold end part to prevent overheating. All this is done to ensure that the filarment does not begin to melt too early. The hot end gets very hot, but the cold end should remain fairly cold.

In addition to conventional extruders (direct feed), there are also Bowden extruders. They differ from standard ones in that the hot-end is fixed on a movable element, and the cold-end is located on the frame of the 3D printer. Thus, these two parts are separated and do not touch. The filament passes into the nozzle through a Teflon tube.

This structure of the extruder allows you to make it smaller, thereby speeding up the 3D printing process. This reduces the reliability of plastic supply.

There are several nuances in the structure of the print head of a 3D printer. Firstly, the material from which the body and parts are made is important. Some companies produce extruders from low-quality, cheap elements. It is best to create injection molded parts from 3D printers because they are more reliable. The performance of the machine depends on the filament feed. Therefore, the feed mechanism must be uninterrupted and reliable.

If the filament gets tangled (because it is thread-like), the feeder may jam. If the parts are of high quality, the filament should still come out, only with small lumps.

Due to the fact that the filament does not adhere strongly enough to the feed mechanism, the filament may slip and cause some delays in the operation of the 3D printer.

When printing, you can use nylon or nylon. Standard print heads (set to ABS) are not able to process it properly, as it is smooth and soft. The feed wheel cannot “grab” the filament strongly enough. That is why, when printing with nylon, rollers with teeth or sharp notches are used.

Also in the structure of the extruder it is very important to take into account the size of the nozzle, because it determines finished work. A typical 3D printer nozzle is 0.4-0.5 mm in size. Another smaller nozzle (0.2-0.3 mm) makes the object print more detailed, cleaner and sharper because the hot filament extruded is thinner.

Particular attention should be paid to the fact that printing using a small nozzle increases printing time. Also, such a hole gets clogged quickly. small garbage and frozen plastic. The feeder must be more powerful in order to push the plastic filament through the small nozzle.

In modern printers it is possible to use nozzles of different diameters. Presently presented different models 3D printers with multiple built-in print heads. For example, the MakerBot Replicator Dual model has two built-in extruders.

Using multiple heads is best for printing two-color objects, as two types of plastic are used. Despite this, printing technology using two extruders has not been thoroughly studied and has a number of disadvantages and inaccuracies.

The two print heads operate independently in the printer, allowing them both to print in parallel. They are firmly attached to the head and the 3D printer uses each of them as needed.

There is also new method simultaneous 3D printing, which is called “Ditto printing”. With this method, both extruders print two identical objects, working in parallel. However this method has a number of limitations: only small objects are printed, one-color or two-color and large, but with a certain structure (it must be repeating and made in the form of a chain).

Also, one of the disadvantages of printers with two print heads is their complexity and too high cost. Installing additional parts makes the extruder large and heavy, which slows down the speed and allows you to create only small objects. During printing, a malfunctioning nozzle can also cling to the finished parts of the object and spoil them, leaving filament streaks.

The extrusion head is a module equipped with a metal nozzle and a cooling fan and is designed to melt the filament and form the product. High-quality extruders for 3D printers are made from metals that can withstand high temperatures. The device is equipped with electronic sensors for monitoring and controlling the process.

The module is supplied consumables from the coil, which heats up to a given temperature and enters the plastic phase. The described extruder for 3D printer filament supplies the polymer to the platform where the object is modeled using the layer-by-layer deposition method. Some devices may use two or more heads for materials of different colors or purposes.

Extruder for 3D printer filament, model selection and installation

The described modules are compatible with certain types installations that carry out the formation of products using 3D technologies. Before trying to answer the question of which extruder is best for a 3D printer, you should determine its type. You can select a head according to its characteristics, in particular, the MK8 model has the following parameters:

• The plastics used are ABS and PLA.
• The maximum nozzle temperature is 260 ⁰C.
• Thread diameter – 1.75 mm.
• Nozzle cross-section from 0.2 to 0.4 mm.

The best extruder for 3d printer has standard parameters power supply: current – constant voltage 12 V. The module is equipped with a high-frequency NTC thermistor, which provides optimal modes heating the forming material. Our 3DIY online store offers to buy an extruder for a 3D printer at a reasonable price. You can place an order by phone or directly on the website. Our employees are ready to assist you in the selection and purchase of components. Call or apply online.

The extrusion head is a module equipped with a metal nozzle and a cooling fan and is designed to melt the filament and form the product. High-quality extruders for 3D printers are made of metals that can withstand high temperatures. The device is equipped with electronic sensors for monitoring and controlling the process.

The module is supplied with consumable material from a coil, which heats up to a predetermined temperature and enters the plastic phase. The described extruder for 3D printer filament supplies the polymer to the platform where the object is modeled using the layer-by-layer deposition method. Some devices may use two or more heads for materials of different colors or purposes.

Extruder for 3D printer filament, model selection and installation

The described modules are compatible with certain types of installations that form products using 3D technologies. Before trying to answer the question of which extruder is best for a 3D printer, you should determine its type. You can select a head according to its characteristics, in particular, the MK8 model has the following parameters:

• The plastics used are ABS and PLA.
• The maximum nozzle temperature is 260 ⁰C.
• Thread diameter – 1.75 mm.
• Nozzle cross-section from 0.2 to 0.4 mm.

The best extruder for a 3D printer has standard power supply parameters: current - constant voltage 12 V. The module is equipped with a high-frequency NTC thermistor, which provides optimal heating conditions for the forming material. Our 3DIY online store offers to buy an extruder for a 3D printer at a reasonable price. You can place an order by phone or directly on the website. Our employees are ready to assist you in the selection and purchase of components. Call or apply online.