Printrbot Play to SKR Mini E3 V1.2 board.

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!

SKR Mini E3 V1.2 Control Board

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.

changed to JST-XH. picture has a Creality 1.1.4 board for tests.
Creality 1.1.4 board (the SKR Mini E3 V1.2 is a direct install replacement for this board) and showing the 12V optocoupler to make the induction probe operate correctly.

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.

Ender 3 Pro 3D Printer

The Ender 3 Pro has great prints considering it’s low price point!

Well I decided to get a new 3D Printer. After some looking and comparing I decided on the Ender 3 Pro. The price point was very good, I picked mine up from the Creality store for $214.99.

Creality Ender 3 Pro
Creality Ender 3 Pro

It was relatively easy to assemble. I took a lot longer than most say it takes to assemble. I did take my time as I have found you save yourself a lot of time and trouble not hurrying in assembly. I tried to make sure that I assembled it straight and true. Even then I found that the gantry (X axis) was sagging on one side. So after about an hour and a half I took a break. The next day I sat down and pulled the X axis apart and straightened it out, no more sag. A minor complaint here is there are no alignment pins to make sure it goes together straight and true. You line up the top of the extrusion with the top of the plates the rollers and extruders are on. BUT, if you watch it you can get it straight. I still need to go through and check the tightness of the bed rollers, there is some play that might be able to be removed.

Another thing I ran into was the filament would not feed into the Bowden tube. I followed the trouble shooting guides and solved this pretty easily. Loosen the Bowden couplers then feed in some filament. tighten the coupler in place. Do this at the hotend also. This solved the problem. After this I checked all of the factory assembled screws to make sure they were all snug.

I will not go through the whole assembly as there are numerous videos and papers on do this right. You should be able to assemble this printer, in less than 2 hours, even if you have never assembled one before. The others I have put together were a different style from Printrbot.

While buying this Printer I was not too happy it needed manual bed leveling. I am not accustomed to having to level the bed before printing. Both my prior printers (printrbots) were self leveling. They had their own challenges, like learning to set Z height in EEPROM, to get it to print. I thought bed leveling by hand would be a big pain in the rear. BUT so far it isn’t hard at all. I now can set it with a piece of paper first time, every time. But then there is my wife. She cannot set it at all. So I will probably end up with a BLTouch, or possibly an induction probe for her.

I will have to say it is easier than it looks if you follow the directions. Plus one of the videos I watched on it had a little G-code file that makes it even easier. The g-code file moves the hotend to the extent of the bed and stops waiting for your to click the LCD panel knob for the next point. Once you get the right feel for the correct resistance on a piece of paper you are right at the right height to start printing.

Once I had everything straight and the bed level I went for my first print. I went for the Cat to print from TF Card. I was surprised that it went very well. It stuck to the bed and came out very nice, lots of detail. It printed on a raft for some reason. It was very smooth and there were no anomalies in the layers. There was just a bit of blob and string at the tip of each ear.

I bought the Pro version because it had an upgraded Y axis and a upgraded Power Supply. It also had the removable build plate which I am not sure is really worth the trouble. Also the Pro version has made some small changes that covered problems with the earlier models.

Ender 3 Pro left side.

A few things that surprised me: It uses an 8 bit controller. The extruder was plastic. How Quiet this printer is! Cable management is kind of messy. Considering there are so many 32 bit boards out there and they are inexpensive I was surprised that they were not using one. And the upgrade board (1.1.5) is 8 bit also, just has quieter stepper drivers. The plastic extruder works fine but a metal one is just not much more expensive. Another surprise is that the printer is 24V. The heated bed and the Hotend heat very quickly compared to the 12V models I have.

So for $22.79 from Amazon I upgraded the Extruder to metal, To a Capricorn XS Bowden tube and it had the recommended upgrade bed springs. There is enough Bowden tube for two installs and better couplers for the tube also. This upgrade took about 20 minutes to install on the printer. I thought the kit was from Creality but it was from Comgrow which sells branded Ender printers. It was well worth the price and time to install. https://www.amazon.com/gp/product/B081DN6RM2/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

Comgrow upgrade kit.
The best first upgrade especially if you plan on using flexible filaments.

There are tons of upgrades available for the Ender 3 series. Extruders, Direct Drive extruders, Hotends, Control boards, fans, build plates, Auto leveling probes,,,,,. But best of all the community has came up with dozens of printable improvements for these printers. Make sure you check which versions you print as there were many small changes between the Ender 3 and Ender 3 Pro.

Overall I am impressed by the prints I am getting from this printer. I will say it is slow compared to my other printers. I think with some tuning and tinkering I can get the print speed up quite a bit. I do plan to move to Auto Bed Leveling in the near future. And I also plan, as part of that upgrade, to move to a SKR Mini E3 V1.2 32 bit controller. I am also thinking of transitioning to a glass bed. A BL Touch or other auto Bed Leveling probe is in my future.

After several prints and cleaning the bed with Isopropyl Alcohol I started having adhesion problems with the removable bed plate. I tried some temperature settings and some bed leveling changes but still had troubles. At this time I resorted to Hairspray. Save yourself this trouble, use hairspray from the start.

I am happy with the printer. It has a great price and prints well. If you want to try out 3D Printing you could choose a worse printer to start with, but this is not one of them! I really do not think you will find a better printer for the price out there!

Future upgrades:

  • SKR Mini E3
  • BL Touch or other ABL probe
  • Printed Improvements

Added some printed upgrades to the Ender 3 Pro;

The first was an extruder knob; https://www.thingiverse.com/thing:3176144

Just printed and installed this parts fan duct; https://www.thingiverse.com/thing:3767143

In between I added this filament guide that uses the old Bowden tube and coupler; https://www.thingiverse.com/thing:3303562

Just added this X tensioner from Amazon. It is a bit of a pain to assemble properly. There are no included directions. Almost every piece can be assembled wrong. If it is not right the belt will not be centered in the extrusion. The smaller toothed pulley means the inner mount tensioner t-nut is right at the very end of the X extrusion. The bolt that is part of the tensioner is a Cap screw. This causes them to use a smaller toothed pulley making the belt essentially longer, a larger pulley would probably solve most of this. If they had used a button, pan or a counter sunk, they could have used a larger pulley. Or they should have made the mount longer. Assembly directions would have been appreciated. Marks on the pieces to help in assembly would have helped also. Online directions would not take that much to include. Overall it does work but could have been better designed to give more adjustment and an easier install. https://www.amazon.com/gp/product/B07X8GSGR7/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1

Another addition is an adapter from Micro SD to full size SD card. I bought the adapter on Amazon and printed the mount for it from thingiverse. https://www.amazon.com/gp/product/B07YHN83NJ/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1 https://www.thingiverse.com/thing:3537808

More on the Control center

While messing around with the Hipstreet tablet I dropped it and cracked the screen. I bought a Unbranded (that is the brand name) 10″ tablet. It had the same Intel Z3537F quad core processor and 2GB main memory. It was also a 32GB storage. It also was upgraded to Win10. I then tried the OTG cable with the power injector. A no go. One end worked for Data, the other for power. It would not work as data and power no matter what I tried.

Side view 10″ Tablet on Play

Next I tried to get a data connection through the keyboard connector. No luck there. It needs a pull down to activate the data port. No firm information on the resistance value. It could be 10K or 100K ohm. After checking the keyboard connector I could no longer charge the Tablet. If it wasn’t for bad luck I would have no luck at all.
So I opened the tablet up. I cut the battery leads. I soldered a small Molex connector into the board. I reduced the LM2596 to 4.1V. Now the tablet is directly powered. Now I had power and Data both. The power system is not optimal. I would like to have the battery in the system as a surge source. I have had some power crashes.
The Control Center works well, but it can take a while for the date and time to correct themselves. The 10″ screen is not as clear as the 8″ was. And the scaling is different. Overall I liked the Hipstreet 8″ tablet better. It was faster (better SSD I believe) and the single cable was a cleaner installation. Size wise the smaller tablet was better overall.
I found it is nice to use a Bluetooth keyboard in conjunction with the tablet. Makes it much easier to change print settings. I setup a public account within my local network. This allows me to send files from my other computers to be used on the tablet. The one problem is the inability to use a USB stick in the tablets for file transfers.

Windows 10 up and connected to printer.

What to look for in a control center Tablet:
Separate power and USB ports. Much easier to setup to operate with the printer
2GB main memory. Allows you to open a web browser while operating the printer.
Decent quality screen.
An extra USB port.
Bluetooth keyboard or Keyboard connector.

I will get you some pictures later.