Kraken Rebuild Details
This page details the zero dollar rebuild of The Kraken to convert it into a Prusa i3 2020 aluminum frame reworking.
The original build of The Kraken suffered from design problems that caused the entire frame to torque and move out of square, which severely limited the printing speed and quality. The Prusa i3 is a well tested design and could be built using parts salvaged from the original Kraken.
Prusa i3 "Wilson"
Because the original Kraken was built using 2020 aluminum extrusion, the new machine would be built into a slight reworking of the "Wilson" 2020 Prusa i3 design. The Kraken's threaded rod are 8mm whereas the Wilson uses 5mm, so parts were slightly modified to accommodate the larger rod and nuts.
- Budaschnozzle 2.0c (replacement for original J-head hot end)
This was purchased before the rebuild, as the old hot end suffered from several failures. The new hot end also allows us to print in other materials besides PLA.
The original frame was printed in PLA, which is not ideal for structural uses. We bought ABS to print parts for the Prusa i3 to keep with the color scheme of the original machine.
Inductive sensor to replace the Z endstop, which allows the printer to use the auto bed tramming in Marlin.
Aluminum plate to replace the borosilicate bed. An aluminum bed is necessary for the inductive sensor, as well as providing a more evenly heated surface. PEI (Polyetherimide) provides a superior printing surface over bare glass, Kapton tape, gluestick, or hairspray. The high temp 3M adhesive is used to attach the PEI to the aluminum print bed.
- Assorted M3 and M5 bolts, washers, T-nuts, etc.
Vitamins were bought to supplement the ones removed from the original machine, in case more were needed during the rebuild.
The original Kraken was disassembled to bare components. The 2020 sections were cut to length for the Wilson. ABS was purchased to print the frame components. The Z-axis parts were modified to accommodate the larger threaded rod and nuts.
The Budaschnozzle hot end was disassembled and cleaned of old filaments. ABS for the frame was delivered. Vitamins were collected and sorted to speed up the assembly later in the build.
Parts for the new chassis beginning to be printed.
Printed parts finished. The majority of the frame was rebuilt, but a few 3D printed parts need to be remade and a few odd vitamins need to be sourced.
A few new parts have been printed. The Budaschnozzle did not fit the standard extruder so a new one was made. The frame was also disassembled so that steel corner brackets could be installed to greatly increase the rigidity of the frame. The wiring was wrapped in new cable management wrap and most of the electronics were ran to the board. A new aluminum Y carriage was ordered to replace the original acrylic bed.
A sturdier aluminum Y carriage was bought and installed to replace the old acrylic carriage. This will help produce parts with less warping due to the less dimensionally stable acrylic.
New inductive Z probes were bought to replace the standard Z axis endstop, as well as an 8" x 8" sheet of 1/4" aluminum and a PEI sheet with adhesive. The inductive sensor and aluminum bed well allow The Kraken to use the auto bed tramming in Marlin, and the PEI provides a superior print surface for nearly all materials over borosilicate, Kapton, gluestick, and hairspray.
The Y carriage belt and heated bed were installed. The RAMPS board is missing it's positive voltage pins for the end stops, so it will need to be modified to add those in order for the Z probe to function.
RAMPS board was modified by Wayne to include the +V pins for the endstops. The board was reinstalled and everything was wired up.
The Kraken lives! Firmware loaded and the printer was configured in Repetier Host. It still needs fine tuning but The Kraken has been unleashed.
Printing parts for the rebuild on the Lulzbot Mini