I have been working on my Printrbot Play 3D Printer to a newer 32 bit control board. The Play is at least 5 years old. In fact it is actually older than that, Mine started Life as a Simple Makers Kit. Then it was upgraded to a Play with a kit from Printrbot. It still has the Ceramic UBIS hotend but has a V2 extruder drive. The Printrboard is a F5 and newer than the rest of the printer due to a broken Micro USB port, a common problem with the F5 boards.
Printrbot Play printers are very solid and robust printers that really deserve an update to newer control boards. They were accurate and reliable printers for there time but budget 3D printers can out print them due to the age and size limitations of their firmware and control board. Considering the move to a 32 bit board is only $37 plus $8 in JST-XH connectors it should be well worth the effort.
Firmware for this move is not really available as yet, sort of, but is in the works. I am rolling my own build with help from files for a V1.0 board to printrbot (Phillip Mally). There is a adapter set of boards being developed right now to make this switch “plug and play” by a guy named Phillip Mally. He is in fact assembling the prototype Beta test “Adaptrboard” release boards as this is being typed. These, with a few additions, should make the swap into a half hour and done deal for most people with no crimping or soldering needed. Firmware is a simple install of a BIN file onto the SD card to install. He has setups for the Play, Simple Metal and the Metal plus (SKR 1.3 board there) being developed. So if you are looking to revive a Printrbot it could be really easy in the not too distant future!
The main problem with the upgrade is the connectors. Printrbot used mostly Molex style connectors with some Dupont connectors thrown in. The SKR Mini E3 vV1.2 Board uses JST-XH connectors throughout. It took me about 3 total hours to remove, Strip crimp and install the new connectors. I am sure that those with more experience at this part could get it done in about an hour. TIP; label all of your wires before starting this job. You will save yourself all kinds of heartache if you do.
WARNING: Realize that Printrbot used a short lead induction probe cable, that went into a dupont connector that is different colored wires. You will need to make sure that that you pay attention to this interchange and label the wires under the printer correctly. While you are at it Printrbot, for what ever retarded reason, chose to put uncovered male Dupont connectors to the fan and the induction probe. These pins are powered and exposed if they come unplugged. This will cause a short and destroy your board if it is not corrected. My brother lost a 2 month old printrboard in just this way. So while you are at it, crimp some JST-XH which lock and provide at least a shield for these pins. Not all of the Printrbot’s are this way so make sure yours is not one of these. If it is make sure you correct it!
The next feat is to wire up the induction probe to make it work properly with the new board. To do this a 12V to 5V optocoupler board is used. You can also use a voltage divider circuit or diode circuit to accomplish this. The induction probe works best if it is supplied at least 6V. But a direct connection to the board only provides 5V. The sensor can operate from 6V to 36V. But if you put more than 5V to the Z stop connector you will damage the board. The Optocoupler allows 12V to power the probe but have an output of 5V to the board. I saw how to wire this up on a post on Facebook in the Prinrbot page by Darren J. Green
Next hurdle is to design an adapter board mount that goes from the printrbot format to the SKR format. Only one hole lines up as far as I can see. Also there will need to be a hole cut in the body to allow access to the MicroSD port and the Mini USB B ports.
Another thing to do is design a LCD holder to use the Creality LCD board for controlling the Printer. I will remount the Laptop to the printer and control it from there as I used to, but there are some unique features to using the LCD like setting the nozzle height just by dialing it up or down with the LCD control knob.
This is it for now so far. The SKR board is delayed until Monday. I will get some more pictures of it and it’s install in the coming days. The induction probe/optocoupler setup needs to be tested to make sure only 5V is output and that it is wired correctly before being plugged in.
Well the SKR Mini E3 V1.2 came in. I drew up several mount adapters to install the board. In the end I rotated the board 90deg. and lined the MicroSD port up with the SD port in the chassis. The USB port is covered but that will be fixed at the next chance with a drill and Dremel with cutting wheel.
After I got the board installed I installed a firmware from Phillip Mally. It immediately showed a “TMC connection error” on the LCD display. But all the steppers were working and it was able to home, including the Z Probe. The Extruder motor was running backwards but that was fixed by swapping the wires in the connector. All of the stepper connectors are wired the same. Left to Right; Red, Green, Yellow Blue, when looking at the board.
Lots of thanks to Philip Mally and Darren J. Green on Facebook. Their post and help made this easier and turned me back from some dead ends. Phillip Mally’s Adaptrboard set will make this project possible for others to resurrect those old solidly built Printrbots with modern control boards.
This lead me to installing VSCode and the PlatformIO extension to build my own firmware. I finally had to watch a video on how to set up the environment properly. Then lots of time trying to figure out build errors. Many of the settings I copied over from the Play/SKR GitHub config.h and config adv.h had to be messed with until the errors mostly went away. Finally I got a working firmware built and it still had the TMC error.
I reinstalled the original firmware and there was no TMC error, so I knew it had to be settings.
I found that he had set Slave address settings and that was causing the error. Of course it took a whole lot longer than this to figure it out. Once they were all changed to zero the error was gone
So after I fixed the error I then had to track down some hardware problems that were causing failed prints. After screwing with the cables the cabling was catching on the bed. And the pulley on the X axis was not centered and had to be loosened and re-centered. I am still hearing some noise from the X rods and bearing, they need to be removed and have a good cleaning. My parts cooling fan was plugged together backwards at the upper end and was not working. And the dreaded “banding” is still there. I need to upgrade to a 4 lead Z screw. A future project.
So overall the project was a success. I replaced the heart of the printer with a 32bit upgrade and made it work. It is unbelievably quiet compared to it’s original board.
Next upgrade projects:
4 lead Z screw
Hotend upgrade. I am thinking of going to the CR 10 hotend, mounted Direct Drive,(same as Ender 3/5 but at 12V) or going to a UBIS 13S. Frankly the UBIS 13s is an easy upgrade with this board. It is more expensive than the ender unit but would not be easily added to the Printrbot extruder drive. A new extruder and a mounting plate would be needed. In the end a 13s will probably end up in it.
An upgraded build surface!!!!! tired of the Blue tape regimen. I am thinking of using a cut down magnetic build plate from one of the Enders. A spritz of hairspray and they work real well.
I also want to get the laptop(control center) back to work on this printer. that means opening up the SD card port to expose the Mini USB connector on the board. The SKR board uses a CH340 connection. It came with the right cable and it is short enough that it might just be right for the job.
Not planning to upgrade:
Heated bed. I have always used this printer for primarily PLA, so I really just do not think it makes sense. BUT! this board, SKR Mini E3 V1.2, was designed for a heated bed, if you want to upgrade yours. You will have to go to a 350W PSU to upgrade the bed. I used a 6A, laptop style, Brick to power this printer.