If you are tired of the time wasted leveling your print bed maybe BLTouch is a good opportunity. Of course, you should not think that by installing this upgrade we will forget to do manual leveling. We simply won’t have to go looking for perfection anymore, because that’s what the BLTouch will think about. This automatic level probe, for this reason could save you time in boring leveling. No matter you have a Ramps, Melzi, Smoothieboard, the BLTouch installs on virtually any electronics.
If this idea intrigues you continue with the reading of this review because I will reveal it completely.
Why use BLtouch
By far the most popular probe in 3D printing seems to be the inductive sensor. That actually has its own because, although the touch sensor has itself a number of advantages in specific situations.
The BLTouch sensor is not affected by the material on which you print. It is well known that the inductive sensor has this limit, so it cannot be used coupled, for example with glass. The BLTouch is usable with aluminum, glass, PEI, buildtak, wood, and any other material. The probe tests contact, so any material is usable.
Since the BLTouch came on the market I have installed it on various printers, finding myself very well. For some machines, the more solid ones, I switched to adjusting the dish once a year. Before this probe I had to make the adjustment up about every 20 days. I must also admit that I spray a veil of lacquer and only rarely clean the plate. This sensor calculates me the 0 of the Z axis with each print, and then counts in its calculation also the hairspray. Convenient, right?
The probe weighs a total of about 10g, so it does not add a weight that can actually bother the extruder group in movement.
It is accurate: it has a standard deviation of 0.005 better than the micro switch and the servo, with a standard deviation of 0.3. Only the inductive sensor is approaching, but as mentioned before you are limited on which printing platform to use. With an automatic probe for the leveling of the bed, the moving mechanical parts depend on the operation of a servant, with BL Touch there is not a servant, only a solenoid.
How does BLTouch work
This probe has a metal “leg” that stretches, and moves towards the plate. As soon as it touches the plate the leg is retracted and signals the distance. This check is done 2 times. The second slower to increase accuracy. The body of the probe is transparent and allows us to see the red light inside. This visual indicator shows the probe running, in self-test mode and when you touch the bed. If there is a problem then an intermittent alarm light signal will allow you to immediately identify that there is a problem. But we’ll talk about it later.
Power peak 300mA
Selectable Z 5v/ 3v3 probe output voltage
Transparent white color
Cable length 150 mm (there is a 50 cm extension in the package)
Compatibility of marlin, repetier, smoothieware software
How to install – Software
BLTouch needs changes to the configuration.h file in the Marlin source code. The required changes are very similar to the configuration of a mechanical sensor.
The necessary changes vary greatly between different versions of Marlin. Among the different versions of firmware. Below you can see the changes to be made to the Firmware even if they are just an example and may not match the correct ones for your version.
Facebook comes to our aid. In the groups that host all the owners of a particular printer, both Italian and foreign are present various firmware versions. You won’t have a hard time finding modified Firmware for the addition of the BLTouch upgade, at least for the most popular machines.
Z Offset calibration
A calibration required when installing the BLtouch is the Z Offset. To tell the Italian the distance between the distance detection and the nozzle, vertically. Although the X and Y values should also be adjusted. Again the distance of the relative axes between the probe and the nozzle.
You can calibrate the offset in several ways. Using firmware where you will have to set the various values (X,Y,Z).
Usb connect the Printer.
You can follow this guide to connect your printer to your PC From the
Repetier Host command window, Enter the following:
M851; notice the number
M851 Z0; sets the offset to zero
The LCD display should show Z plus 0
Now slowly move the Z-axis down until the nozzle is at the right distance from the print plate. You can measure the flat nozzle distance using a thin piece of paper. Or, for greater accuracy by starting printing several times and changing the offset as you go to get a great first layer.
From the display go to The Menu then Prepare / Move Axis / 0.1mm / Move Z
Note the Z-axis value on the display should be something like -1.5
M851 Z-1.5; to set the offset obtained in the previous step.
M500; Stores values in EEPROM so that it does not recover when you turn the printer on and off.
If you find that you need to increase or decrease the gap, then do the following:
M851 Z-1.4; To increase the distance
M851 Z-1.6; To decrease the distance
M500; as always to save the value to EEPROM
How to install – BLTouch
Simple to install at the hardware level, only two connectors to connect. One for the servo (3 pins) and one for level sensor (2 pins). You can follow the photo here to connect the BLTouch to the card. For the actual installation of the sensor you will need a “mount”. This is printable and can be found for any printer on the well-known 3D Model Warehouse: Thingiverse.
Once you have installed this mount you will have to adjust the height of the sensor with respect to the nozzle. The indications say 8mm, with a minimum margin of error. To install very precisely you can put the nozzle in contact with the plate, use a laundry thickness, such as paired washers until you reach a height of 8mm and use it as a dima.
Errors and cleanup
Sometimes it happens that the bar line, for a thousand reasons it freezes. For example, I used to block myself because spraying the hairspray would settle on the bar and not allow it to move. A wet rag and everything was resolved in less than 10 seconds. Other causes can be possible strokes or measurement errors. Some firmware have the DEBUG option. Just one click and everything works again.
I personally proved that even in the absence of the debug key there is a way to make it operational again. Just push up and down the bar line a few times while it’s in error and on restart the alarm will be cleared and will start working properly again.
This upgrade is designed to save you time. Obviously as a good Maker you can use this time to print more!
So why not invest in a BL Touch sensor to save yourself the hassle of manually leveling the plate very often?.
At the moment there are multiple versions of the BLTouch on the market, and I will give you 2 alternatives.
The first one is the originalsensor, which I have used since its first release, theoriginal BLTouch,with an excellent components of the Anticlabs, at about 40 dollars. It can be purchased on AMAZON without shipping costs and receiving it in 3 days.
The second choice is a copy of Geeetech, which I have not tried personally but many users use without major problems. Purchased at about 29 dollars. It can also be purchased on AMAZON at the same features described above, with no shipping costs receiving it quickly.
Which one to choose? The decision is up to you!