Introduction: Bltouch Red Led Mod
As many of you know if your looking at this, that red led on the bltouch can be a real pain when it comes to using your web cam in octoprint or the spaghetti detective or just time lapses.
After doing some digging and research I found out there is no simple way to turn this off or on. I'm guessing that it could actually be accomplished with a software update to the bltouch mcu that would add another pwm command to allow turning it off via printer firmware commands. something like; Turn Red Led Off - M280 px Sxxx.
Since I don't have access to the bltouch firmware, hence was born this bltouch mod. Be forewarned, this is not for the faint of heart and you may even ruin a perfectly good bltouch in the process! However, if your brave and have patience you will succeed!
Why would I do something like this? Ummm duhhh because we can! Besides, for some of us, printers are like some cars, we just love to mod them!
You'll need a genuine Bltouch by AntClabs. I don't know what's inside any of the clones.
Soldering iron, hot air rework if possible, smd breakout board, 0805 led, 0805 resistor, .1mm enameled wire, some solder wick, isopropyl alcohol and some awg30 silicone wire.
Step 1: Open the Bltouch Up
This is the tricky part. There are 2 super tiny delicate wires for the coil that connect to the circuit board. Start by using an exacto knife and gently pry up the end of the board on the push pin side. Slowly lift it out as seen in the pic. If you look closely, you'll see where I actually broke and repaired the wires from my first attempt on opening one up. I had another so figured if I couldn't save it, it would be my guinea pig. Needless to say I was able to save it and it's actually in use as we speak and works great.
Step 2: Remove Red Smd Led
Now that you have it open it's time to perform some surgery. If you look at the pic of the circuit board you can see where I've removed the red smd led. I used a hot air rework gun and gently pulled it off after some gentle and focused heat. You may be able to do it with a fine tipped solder iron, but I didn't try. You may be able to cut it out but just be careful not to damage the pads. After which some solder wick and isopropyl clean up we're ready for the next step. Extending the control ground wire.
Step 3: Extend Control Wire
I decided I needed a really fine wire to sneak the control wire out to where I could connect a wire to it and run it where I needed. I had a small spool of some .1mm enameled wire which seemed like the best choice. After removing the enamel from one end I soldered a piece to the control pad as you can see in the pic. Then I just routed it out and snapped the board back where it belonged. Careful not to damage those 2 wires!!
Step 4: Solder Enameled Wire to Silicone Wire and Epoxy Down
OK now we run that enameled wire up near the plug, solder it to a bigger wire. I used a 30awg silicone wire. Then just mixed up some epoxy and glued the wire down so it would stay put. I considered removing the female plug and modding that and hook the enameled wire to it, but decided to just play it safe at this point. A bit uglier than I would have preferred but no one will see it anyway. Well except me! And it will probably haunt me until I come back and clean it up! lol
Step 5: Mod Complete
Now we have our bltouch all back together and a new wire coming from the bltouch MCU that will turn on our remote led! wooo!
Let's make up something for our led! Fun time now!
Step 6: Making Up Something to Hold the Led
I'm running an Artillery X1 V4 so your setup will be different than mine if you put it on another rig. This should at least give you some idea's to work with that you can use to create your remote led setup.
Since I've already done some other major mods to it I had a couple places to source the voltage needed for my new remote led. Keep in mind the led you want to use and it's power requirements. I created a small circuit board from some smd breakout boards I ordered from amazon or ebay. I used an 0805 purple led (I don't know? I like purple!:) and since I was sourcing 5v from the bltouch I used a 0805 90ohm resistor. Since I wanted it to be serviceable, most of my connections are jst. The small switch you see on the board is to turn off or on my led's mounted to my duct. If you look closely you'll see where I made a small jumper to connect the positive side of the led to the resistor. Remember, you need to have a common ground to the bltouch in order to source a separate voltage source! Also, careful on led sizes. That mcu won't directly drive much larger of an led without adding some sort of transistor switch.
Step 7: Success!
The last couple pics shows it all mounted up and in action. Away from the camera! We still have full use of the led's ability to display an issue. Like when it does the auto level it will turn on/off etc.
Hope this helps someone out trying to get that blasted led disposed of!!!
Hey Antclabs!!!! How about a firmware update and a toggle! :)