- Aug 04, 2017
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How to Properly Print the First Layer?
The first layer is the most important single factor that determine if your print will fail or not
Having an excellent quality 3D printed model depends on many factors that must be considered to avoid partial or complete failure of the print. These factors include constructing a good 3D model, printing material, proper settings from slicing software and how precise a 3D printer can print. It is important to ensure that the quality of the current layer is in great condition for the subsequent layers to be printed successfully.
The first layer of any 3D printed model is one of the most important factors that contribute to building the model properly. Before starting producing your 3D printed model, it is important to take some time considering the problems about the first layer such as parts detaching and warping that can cause a complete unsuccessfully print. So, in this article, we will discuss the failure reasons and recommendations one should follow to minimize the probability of a nonsuccess print.
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1. THE PRINTER'S BED (BUILD TRY)
It is a plus to have a heated printing bed when printing with PLA material (recommended 60 to 65°C), and it is a must to have heated print bed when printing with ABS (recommended 100 to 105°C). With heated printing bed, it is increasing the adhesion between the material and the print bed, which prevent warping. Learn more about BotFeeder temperature and printing guide
Leveling the bed is one of the most important tips when it comes to a quality and a successfully 3D print. As having an unleveled bed leads to deviation in the distance between the nozzle and the bed. Thus, it can result in two cases; the material does not get out of the nozzle as the nozzle is too close and touches the bed, or the content gets out of the nozzle and does not stick well against the bed due to the nozzle is too far away from the bed. Having a very precise leveled bed is strongly recommended. Make sure that the bed is clean, as dust or oil can affect the adhesion of the first layer.
2. BED MATERIAL
The bed and printing material need to be chosen carefully to ensure the adhesion of the first layer; there are many options available such as blue painters for bed material with PLA as a printing material. Also, the PET (polyethylene terephthalate) and Kapton are good bed materials to be used with the ABS (Acrylonitrile-Butadiene-Styrene). So, you need to make sure that the bed surface is suitable for the printing material to stick well. Few recommendations are using a general-purpose glue stick on the build surface directly; this can be wiped easily with water. Or using Jell-O which is commonly used with the layer adhesion, typically you can use 10:1 Jell-O powder to water, like a 10g powder to 100ml water. This mixture works as gelatin and helps the layer adhesion. We have now mentioned some recommendations about the bed material, and more options are available depending on the makers' experience.
3. THE EXTRUDER
There are two problems with the printer’s extruder
Proper calibration of extrusion multiplier is also critical. Under extrusion can cause not enough material coming out from the nozzle which results in bad first layer adhesion. And over extrusion can lead the filament to bleed out of it and the bed gets messy.
Recommendations to solve those problems:
I. Lower speed:
Reducing the extruder speed helps the molten material to stick well and to have a great layer built. Commonly, you can minimize the rate to 30% to 50% of the average speed.
II. Calibrating extrusion rate:
At high extrusion rate you get too much material on the bed, and when the extruder moves, it may lift some of this material causing deviation of the required design. And if this material has cooled down then it will detach the layer from the bed or cause warping. So it is important to have a well-calibrated extruder.
III. Extrusion width:
Increasing the extrusion width at the first layer helps the layer to adhere more on the bed to be a well-constructed base for the model.
IV. Initial Layer Height
As the molten material is extruded from the nozzle in a cylindrical shape, it has forced into a round hole out of the extruder so that it will be laid smoothly on the bed with a little contact surface. So, the extruder should be lowered to a suitable height (thickness of an A4 sheet), depending on the layer width, to force the molten plastic to be compressed seamlessly to the bed to have the larger contact surface. To achieve this, it is common to set the first layer height at 90% of the other layers.
It is recommended to shut down the fan for the first three-layer to let the molten material stick to the bed and get bonded well. It makes no sense to increase the bed and extruder temperature while having running a cooling method. This is also recommended for the next few layers.
Anything causes air to flow near the printer while setting-up the first layer can cause failure. Such as a door that opens many times, a fan, an opening window, and so forth. This can cause the layer to warp or moves to a different spot. However, utilizing brim/raft can be a great help for the first layer printing.
5. A GENERAL GUIDE FOR A GREAT FIRST-LAYER PRINT:
- Level the bed as perfectly as possible.
- Correct distance between nozzle and bed is approximately the thickness of a single A4 sheet.
- Clean the bed and make sure it is free of oil or dust. Choose the right material for your printing bed and the material you are going to print with (ex. blue tape or glass for PLA, Kapton sheet or ABS juice for ABS).
- If possible, use a heated bed ( 60 to 65°C for PLA, 100 to 110°C for ABS)
- The nozzle is free of jamming and spool is free of tangling.
- Print with lower speed for the first layer (ex. 20mm/s).
- Print with high temperature for the first layer (ex. 200°C for PLA / 230°C for ABS).
- Print with larger width for the first layer or increase extrusion multiplier for the first layer.
- Turn off the cooling fan for the first three layers.
- Add brim or raft to the printed object.
- Try not to utilize the maximum space available for your print bed. This may cause uneven temperature and/or levelling issues.
- Do not print under fan dust or air conditioning.
All the mentioned factors can lead to failure or success of the first layer print as well affecting the other layers. The failure can be represented in many results such as warping, detaching from the bed, shrinking, messy layer, stringing (which means that the filament is oozing from the extruder and dragged to the next point). All of these can lead to a complete failure of the 3D printed model, which can take up your time and waste the printing material. So, it is recommended to follow the mentioned general guidelines. Also, make sure to check the 3D printer settings such as the bed and the extruder temperature, the flow rate, printer speed, extruder height, and periodically examine and maintain the mechanical system. Finally, it is important to consider all the factors affecting the success of the printing process. It is crucial to observe the print of the first layer and the next few ones to determine whether or not to continue the printing process.