BL Touch Punch pin

The inclusion of leveling sensors in 3D printers has been one of the most exciting developments in 3D printing in recent years. Leveling sensors not only free the user from the necessity of manual bed leveling, but also, in some cases, ensure proper bed adhesion by compensating for flatness discrepancies of the printing base.

Leveling sensors come in three main types: optical proximity, inductive proximity and mechanical contact sensors.

1. The first type, optical proximity sensors, are characterized by high precision and reproducibility. Their only drawback is that they only work properly on clean and well maintained glass printing bases. This means that they cannot generally be used with plastic bonding bases such as Buildtak.
2. Inductive proximity sensors are a bit more popular. They are integrated into printers such as the Prusa MK3S. What makes inductive sensors stand out is their low cost and ease of installation. The main downside of inductive proximity sensors is their relatively low accuracy and repeatability, and the fact that they only perform well on metal bases.
3. The last type of leveling sensor is the mechanical contact sensor. Their low accuracy and poor repeatability are compensated by their ability to work on any printing surface. Nevertheless, contact sensors need to be combined with a servo motor that is responsible for deploying and picking up the sensor at the time of leveling. This makes the mounting of mechanical contact sensors complex and increases the volume and weight of the print head.

BLTouch, an innovative leveling system developed and patented by a young Korean engineer Paris Kyung-yeon Lee, is a level sensor with contact based on the Hall effect. BL Touch integrates the servo motor to deploy and pick up the contact pin.

Video 1: The crowdfunding campaign for the BLTouch auto bed leveling sensor. Source: Antclabs.

BLTouch stands out among other leveling sensors on the market thanks to its versatility and accuracy (standard deviation of ≤ 1 %). What’s more, its compact size makes it a perfect option for both domestic and professional 3D printers, without the need for many adjustments. Even some of the more advanced extruders such as the Bondtech DDX for Creality printers or include the option to mount the BLTouch sensor by printing a simple adapter.

Image 1: The BLTouch leveling sensor. Source: Filament2Print.

BL Touch has a transparent tip included as standard. This tip may wear out over time with use, and the user may need to replace it with a new one.

When replacing the BLTouch tip, the user can choose between two options:

• Standard transparent tip
• Red premium tip

Image 2: The replacement push pin for the BLTouch sensor. Source: Filament2Print.

The transparent tip would be exactly the same as the standard product, while the red tip is made of a more rigid material, offering higher precision and therefore offering a better guarantee of the quality of the base leveling.

Both tips are compatible with BLTouch Smart V2.0 or higher.