K2 Plus CFS Mod - Heated Chamber - Space Pi Double

I decided to build this mod for the CFS just to see if it could be done.  Like many of you, I received the Space Pi dual roll filament dryer with my K2 Plus preorder.  I have multiple other filament dryers, and really no use for another stand alone dryer.

The CFS does not have active chamber heating/drying capabilities.  This mod, will correct this.

This is very much a beta.  I only have one CFS to test this on.  Feedback from users is critical!  Feel free to DM me with any thoughts/improvements.  Ratings & makes are appreciated!

Note - this mod is not easily reversible as you’ll have to cut 5 holes in your CFS case.  4 for intake/exhaust vents, and 1 for the power switch.  Please note you’re making this modifications of your own accord and free will.  I take no responsibility for any damage you may cause in the course of the modification.  You will be voiding your warranty on the Space Pi, and possibly on the CFS depending on any future issues you may have with it.  Please consider this before starting!!!  
 

This mod is purely taking the Space Pi, and integrating its hardware into the CFS.  CFS still operates as it originally did, space pi still operates, and is powered, independently.  You will reuse the Space Pi’s power cord to supply dedicated power to its components.  

None of my links are affiliate.  If you’d like to support this design - https://ko-fi.com/ice992

• EDIT-  a few of you contributed and I really want to say thank you.  I’m a hobbyist like many of you, I make designs at night when I can spare the time.  I work very long weeks - so the contributions are amazing and I just wanted to say thank you!
   

I’ve tested this now for almost 48 hours straight - with PLA, ABS, ASA, and PETG.  I only had troubles with some really cheap, and really old ASA.  I think this was just related to the CFS, no issues from the chamber heating itself once I determined the actual chamber temps.

One thing to note - the chamber temps, and the Pi/CFS temps are NOT accurate.  I found a temp variation by up to 11* C.  For PLA - I set the dryer temps to 45*C and it’s perfect.  50*C, with the noted chamber temps makes some PLA too soft.  I use 54*C for ASA/ABS.

Here’s what my testing showed:

Required:

• Ribbon Cable Extension.  Male to Female, 10 pin, 2.54mm pitch, double row. 10-12” long.  I used this one:  https://a.co/d/1oCxQt7
• 14Ga wire for extending heater power (3-4” extension needed)
• Solder/Shrink wrap for extending the heater power wires
• 2.5mm Drill bit (or 1/8th in)

Optional:

• Solder Seal wire connectors - I prefer using these over solder and shrink wrap independently.  I use this kit:  https://a.co/d/1940XVY
• Ferrules & crimper - this makes the ends of your power wires nice and clean - and makes connecting/disconnecting super simple.  A few options:
  • Starter kit - https://a.co/d/1NvKYol
  • Kit with nicer crimping tool and more ferrules - https://a.co/d/gqHPyOy
  • Ferrules alone if you already have a crimping tool - https://a.co/d/brzgdLj
• Rotary tool for cutting - Dremel or similar
• Zipties - small/short

CFS Disassembly:  https://wiki.creality.com/en/cfs/replace-cfs-mainboard

-Make sure you retain all screws - keep them separate from the Space Pi Screws.  Remove all zipties - 

Space Pi Disassembly:

• Note - before you disassemble - please validate your Space PI functions as intended.  There’s been reports of Space Pi units which have bad sensors from the factory.  Ensure your unit throws no errors before disassembly.  
  • My unit - throws an E4 error.  This is essentially a check Creality put into the Space Pi heater to ensure the chamber is heating adequately in a given time.  I’ve found that heating the unit up in 3-5* increments is required.  The time check is 10 min.  The unit will heat the chamber 3-5* in 10 min.  If I go from cold, to 50*, I will have an E4 error, and will have to power cycle the Space Pi heater.  
• No Creality guide exists that I’ve found - there’s a few pictures on a Reddit thread from a single roll space pi:  https://www.reddit.com/r/Creality/comments/1gdlgta/disassemble_creality_space_pi_filament_dryer/?rdt=40757
• Short instructions:
  • Turn unit over - remove rubber pads on bottom
  • Remove 6 screws beneath the rubber pads
  • Remove the black plastic cover on the screen - it’s a .5mm piece of plastic - pry one edge - glued to the face lightly.  This piece is optionally reusable as part of the mod.
  • You can remove the screws exposed - you will not be able to remove the screen itself until you take the bottom cover off and unplug the screen from the main board.
  • Remove bottom cover
  • Remove all screws you find inside - the main board screws will be used to mount the main board to the printed parts.
  • Take a picture of the wiring on the main board - the heater blocks should not be polarity sensitive - but just in case it helps to keep a reference.
  • Keep all removed screws together - you will reuse some of them with the mod.
  • You should end up with all of the parts below removed, and an empty Space Pi shell.
    • Mainboard
    • Power Switch/plug
    • 2 fans
    • 2 heater blocks

The Space Pi plastic isn’t needed.  Set the parts aside, as well as the screws.  You will end up with excess screws from the Space Pi, but you’ll use these to affix the main board, screen, fans, heater blocks, and printed base.

Printed Parts:

• Baseplate
• Duct Covers
• Intake Ducts
• Output Ducts
• Screen Mount
• Optional - Screen Mount Template - this is for printing to drill mounting holes into the CFS faceplate.

Print Settings I used:

• Material:  ASA/ABS - these parts will come in contact with hot air, and hot parts.  PLA will deform.  Note - ScreenMount can be printed in PLA - it’s not exposed to heat in any way.
• Walls: 4
• Infill Pattern:  Rectilinear or Gyroid (my preferences)
• Infill: 15-20% - note - this really only applies to the baseplate - everything was designed to end up all walls with these settings.  There’s a few small pockets of infill in the intake ducts, but not many.
• .8 mm top and bottom thickness
• First layer height: .2mm
• All other layers: .2mm
  • I did use dynamic layer height down to .10 on the exhaust ducts
• Supports - enabled - manual - on build plate only (1 intake duct requires support inside the fan hole - I could not get around this)
• Brim - only parts that required a brim in my 30x printing these parts during iterations and testing:  Exhaust Ducts.  I used Brim, inside/outside, 5mm.

I’ve included a ScreenMount hole template for drilling the holes in the CFS faceplate.  I will be making cut templates for the intake/exhaust vents - I just have not completed them yet.

The intake/exhaust covers, are glued in place after all assembly.  These are only to prevent silica from entering the intakes, and cover up the cuts into the plastic case.  (My cuts looked terrible - I was freeform cutting).  I did not make a beauty cover for the power switch cutout yet - given it’s on the back of the CFS, I wasn’t too worried about it.

Print all parts and test fit.  You’ll assemble the entire mod, and slide it into the CFS case.  You can screw it in place with 1-6 screws.  I used 2.  (You’ll see the holes that align on the backside of the CFS case)

Where the intake ducts interface with the intake duct walls on the baseplate - I used a few drops of glue to seal the duct. 

Baseplate - set one exhaust duct, and one heater into place - screw down.  Repeat for other side.  Ensure heater block wires are pointing toward the middle of the baseplate.

At this point, you can test fit the baseplate into the CFS - this is how I determined where to cut the holes for the exhaust ducts.  Test fit, and scribe lines on the CFS plastic along the edges of the ducts.  I will be creating cut templates that should eliminate this step.  I will also create templates to help with the Intake Duct holes.  These will be cut into the top half of the desiccant trays back wall on each side.  

Attach fans to baseplate.  I ran the screws all the way in, and then backed them out again to allow the intake ducts to be attached.  (They mount to the fan screws).

Once assembled - attach the Dryer main board to the 4 mounting holes.  Before attaching - I straightened the 2 sensors on the bottom of the board so they would stick down into the flow of air.

At this point is when I extended the Heater module wires.  I joined them into a single extension.  The baseplate has zip tie cut-ins for easier cable management.

Slide assembly into CFS, screw into place.

Attach screen ribbon cable extension

Mount Screen to faceplate, cut hole for ribbon cable to passthrough before mounting.

Reassemble, glue duct covers in place, and enjoy!

If anyone is able to take detailed pictures and put them into a guide - I will feature it here with credit!  This took me weeks to design and fit - I didn’t get good pictures along the way.

Last note - I will be also creating this same mod, using an Sunlu S4 dryer at some point in the near future.  The Space Pi is a great dryer, but it lacks features that the S4 has, not to mention the S4 is designed to heat a similar sized chamber.

I have included the STEP file for all parts listed - I know many of you are quite a bit more skilled and will come up with some great remixes!